Presentation on theme: "Table of contents JM. Piau Premium pavements from alternative material for European roads – Keynotes 3 F. Sinis Premium pavements from alternative material."— Presentation transcript:
1 Table of contentsJM. Piau Premium pavements from alternative material for European roads – Keynotes 3F. Sinis Premium pavements from alternative material for European roads – What is the situation? 15K. Krass The need for environmental assessment to promote sustainability 33D. François General assessment methodology for best use of alternative materials 49H.Van der Sloot Comments to the assessment method - Environmental Part 77S. Boetcher Prototype environmental annex to product standard 89B. Koenders Health, Safety, Environmental assessment 105S. Colwell Reaction to fire performance of pavement materials 121E. Nielsen Mechanical Assessment Towards functional specification irrespective of type of material (Modelling) 131C Nicholls Implications of asphalt deformation results for standardisation 135S Soliman Techniques for recycling 151
3 Premium pavements from alternative materials for European Roads SAMARIS final seminar Keynotes Jean-Michel PIAULaboratoire Central des Ponts et ChausséesSAMARIS Pavement Stream scientific coordinatorHow to guarantee the construction or maintenance of «Safe and durable pavements from recycled and residual materials» has been the leitmotiv of SAMARIS Pavement Stream.This main objective has determined the research to be undertaken during this 3 years project and the content of the deliverables to be produced.Now it is the aim of this 2 days seminar to expose the main results obtained within the project and try explain which benefits can be drawn from them by the road community as well as by researchers.
4 Recycling: a multi-facet world Recycling in pavement construction :a generic wording and a complex worldcovering at least 4 different situationsProper recycling of road materials (untreated, bituminous, cement materials)without change of functionEx: Base course materials base course materialswith change of functionEx: wearing course materials base course materialsIn place or after storageRe-use of initially non road materialsEx: demolition concrete from buildings, scrap tyres,…First use of materialsEx: industrial by-products, waste material (MSWI),…To start with, let us recall some general preliminary considerations about recycling.First it must be acknowledged that recycling is often used as a generic word actually covering different situations, that need to be highlighted for the right understanding of everybody.In particular, in the domain of Pavement construction and maintenance, recycling covers 4 situations at least:the recycling, properly speaking, of road materials (untreated, bituminous or cement bound materials) without change of function; for instance base course materials reused as base course materialsthe recycling of road materials with alteration of function; for instance reused of wearing course materials as base course materialsIn these 2 cases, recycling may be done in place or after storage of materials in stockpilesthe re-use of non-road materials, which have had a “previous life” in some other application; for instance, demolition concrete from old buildings, scrap tyres from old tyres, …the first use of alternative materials, not considered (yet) as standard road materials ; most often it concerns the case of some industrial by-products, such as steel slag, considered before as “waste” materials. Solid waste from municipal incinerators (MSWI) also belong to this category.Beside it must be emphasized that the use of “recycled” resources is often only partial, the final materials being obtained by mixing recycled with natural materials.In SAMARIS, the 4 situations described above are envisaged turn and turn, depending on the considered research topics and deliverables.The following slide indicates more precisely the main alternative materials (apart the road materials themselves) which were considered in SAMARIS, in particular inside the technical guide D29 (see further).
5 Main alternative materials considered in SAMARIS Industrial by-productsSlagsSteel slag (basic oxygen and electric arc)Air cooled blast furnace slagGround granulated blast furnace slagCoal bottom ashCoal fly ashFoundry sand“Waste” products (before re-use)Mining waste rock (colliery spoil)Building demolished by-productsMunicipal solid waste incinerator bottom ashWaste glassScrap tyresThis slide indicates the main alternative materials considered in SAMARIS, especially in the “Guide about recycling techniques” (deliverable D29).Also this list closely corresponds to the alternative materials (apart road materials themselves) most widely used throughout the different countries in Europe for pavement construction or maintenance.
6 Potential AdvantagesAdequacy of Recycling with the general objectives of Sustainable Development PolicyPav. Const. needs important quantity of “granular” materialsSpare of natural resourcesReduction of existing stockpilesDiminution of the storage of new waste materialsLess transport of materials (especially, in the case of in place recycling) : save of energy, less damage to roads, increase of road safety,…Possibility of economical savingsThen it must be acknowledged the important role that road construction has historically played and should continue to play in the future for the promotion of recycling (with the different meanings listed before). Actually the reasons for this can be easily found by considering the numerous potential advantages that recycling offers facing the specific context of road construction or maintenance.First it must be reminded that pavement infrastructures incorporate huge quantities of granulates, either for untreated or bounded layers.Thus “recycling” , meaning either the re-use of road materials or the use of alternative materials, makes it possible to spare natural resources of granular materials.At the same time recycling makes it possible to reduce the size of existing stockpiles and to decrease the storage of new “waste” or residual materials.Also it is expected that the wise practice of recycling will reduce the transport of materials, by making it possible to use resources closer to the job sites than natural resources, which is already true in the case of in-place recycling. Thus positive consequences such as save of energy, less damage to roads, increase of road safety are also expected from recycling.&&&Finally all these reasons show the possible benefits of “recycling” which meet most of the main requirements of sustainable policy.
7 Difficulties & Potential Dangers A priori Recycling involves a wide diversity of materials, generally less well controlled and known than standard ones. Those ones must be:No detrimental to the environment and the health at short term, especially for workers on job siteNo detrimental to environment and health at long term, especially to ground waterIn accordance with the expected performance of the structure:DurabilityProperties of the wearing course - skid resistance,…However “recycling” also contains some difficulties and potential dangers, which need to be overtaken to really be beneficial. In the opposite case, recycling could rather induce the risks of detrimental effects.Most of the obstacles derive from the facts that the materials and techniques used in “recycling” introduce a wide diversity of materials, which are at the same time less well controlled than standard ones and less well known.Therefore before using recycled or alternative materials, it is essential to check that these one will not be detrimental to the environment, nor to the health, be either at short term (at the time of construction and material handling) or at long term.It is also essential to make sure that the ensuing pavement structure will have all the mechanical and use properties (ex: skid resistance) expected by the road owner, especially in terms of durability.
8 Complementary approaches to solve the problems International bibliographic study (and transposition) SAMARIS states of the art & guides, gathering European experiencesField experiments at limited scale Not covered by SAMARISFacing a new “recycling” application (new material, new technique), different complementary approaches can be envisaged to solve for the obstacles listed before.The first one is to undertake bibliographic studies (possibly including scanning tours) at the international level. Indeed an application which is new for a country, may have already been experimented in another country because of different historical, geographical, industrial, economical, … contexts. Then the question which arises is to know how far such results can be transposed from one place to another one for which material processing, climatic, traffic conditions, etc, may differ.With this ambition, a large place has been given in SAMARIS to the collection, organisation and restitution of information available among different European countries.Field experiments at limited scale is another way of testing new application. However to be informative, these ones have possibly to be “instrumented” (ex: by collecting leaching effluents, measuring strains, …) and before all followed with time, over long periods. Indeed the main drawback of field experience is the lack of time acceleration especially from the environmental and physico-chemical points of view (whereas the traffic can be accelerated on ALT sites). Another drawback of field experiments is the relative limited number of parameters which can be tested considering all those which can be varied in pavement structures, such as the type, superposition and thickness of layers.No specific consideration has been devoted to this aspect in SAMARIS.
9 Complementary approaches to solve the problems International bibliographic study (and transposition) SAMARIS states of the art & guides, gathering European experiencesField experiments at limited scale Not covered by SAMARISGlobal performantial assessment of alternative materials at lab scale, covering :Environmental and health aspectsMechanical performance & durability aspectsChoice of the best application as a function of the material and context Main focus of SAMARIS pavement streamPre-treatment of alternative materials before road applicationSorting , Homogenization, Deactivation, ……Another approach is to develop a global performantial approach for the assessment of alternative materials, covering the environmental, health, mechanical and durability aspects. This means:to develop general and specific assessment methodologiesto select or develop new laboratory tests, for which possibly field relevance and predictability have been established (see the last slide).Then the main efforts of researchers in SAMARIS pavement stream have been driven towards this objective.&&&Finally, it must be emphasized the importance and the care to be given to the pre-treatment phases of alternative materials, upstream their re-use in pavement structures. In particular the recyclability of materials may depend on their pre-processing on their storage site, such as sorting, homogenisation (including in terms of grading), deactivation with regards of chemical reactions which could arise in their future environment, etc.Thus the main processes applied to the most important alternative materials used today are recalled and described in the technical guide D29 developed in SAMARIS project.
10 Elaboration of alternative materials Industrial process (WP6 : Francisco Sinis)D12General assessment methodology for the best use of alternative materialsConcept of use-scenario(WP3: Denis François)D4, D9, D16Assessment of mechanical performances in labPerformantial approach of permanent deformation in UBM & AM (WP5: Erik Nielsen)D6,D10,D11, D27,D28Detailed assessment of environmental, health and safety aspectsDraft to environmental annexes to standard products(WP4: Cliff Nicholls)D7,D23,D24 D8,D20 (fire)Technical guidefor the recyclingof the main generic families of alternative materials(WP6)D5,D15,D29This synoptic from SAMARIS pavement stream summarizes both the objectives which have been considered in this project stream as well as the composition in work package (WP number + WP leader’s name) which was given to the research work.It also indicates the list of deliverables which were produced in each task. (Use the following slides to have the correspondence between the deliverable numbers (used here) and their titles. The main deliverables are indicated in bold characters).The structure given to this seminar also derives from this figure. Thus after this introductive session, there will be :a presentation from WP3 ( “central rectangle” ) about the development of a general assessment methodology for the best use of alternative materials (mostly from D16).presentations from WP4 (“bottom left rectangle”) about some specific assessment methods concerning health and safety aspects (D23, D24) (including the reaction of asphalt materials to fire, D20).presentations from WP5 (“bottom right rectangle”) about some specific assessment methods concerning permanent deformations in unbound materials (D27) and asphalt materials (D28).presentations about the technical guide dealing with the recycling of the main (non-road) alternative materials (D29).
11 SAMARIS deliverables (1/3) Elaboration of alternative materialsD12: Recommendations for mixing plants for recycling works *General assessment methodologyD4: Report on existing specific national regulations applied to material recyclingD9: Critical analysis of European documentsD16: Report on a methodology for assessing the possibility to re-use alternative materials in road construction *The deliverables which will be more specifically presented during the seminar are indicated with a star.
12 SAMARIS deliverables (2/3) Assessment of environment, safety & health aspectsD7: SoA on test methods for the detection of hazardous components in road materials to be recycledD23: Test methods for the detection of hazardous components*D24: Environmental annex to road product standards*D8: Review of road authorities’ positions on reaction to fire of pavement materialsD20: Testing procedure for reaction to fire of pavement materials *
13 SAMARIS deliverables (3/3) Assessment of permanent deformation in UBM & asphalt materialsD6 : Data base and reference full scale testsD10: Models for prediction of permanent deformation of unbound granular materials in flexible pavementsD11: Models for prediction of rutting in bituminous surface layersD27/D28: Calibration and validation report for modelling of permanent deformation of unbound (D27) and bituminous (D28) materials in flexible pavements and recommendations for the definition of performance-based specifications*Technical guide for the recycling of the main alternative materialsD5: Literature review on recycling of by-products in road construction in EuropeD15: Report on the situation on recycling in Central European countriesD29: Technical guide on techniques of recycling*
14 Precision about performantial approaches for road material assessment In terms of road material design, the current practice is based on a mixed approach between :recipe approachperformantial approachRecipe approachBased on material components (ex: fine, sand, granulates, binder,…)Components specificationsMix design based on the mass or volumetric content of the different componentsIntensive use of empirical relationships fitted by feed-back from field observationAdapted to standard, well-known (natural) materials and formulaePerformantial approachRather based on the direct assessment of the materials themselvesTry use as much as possible material models and structural models, for the prediction of the material behaviour within the structureBetter adapted to innovation and to the introduction of a wide diversity of materialsThe difference between recipe and performantial approaches can be extended to other characterisations than the mechanical one: environment, health,…
15 Francisco Sinis Transport Research Centre of CEDEX Premium pavements from alternative materials for European roads What is the situation?Francisco SinisTransport Research Centre of CEDEX
16 Towards a sustainable development growing commitment to preserve the environment making it compatible with social and economic developmentUnited Nations conference (1992)declaration of Rio (1992): Sustainable developmentaction programme for a worldwide environmental policyEuropean Uniontreaty of the union (art. 2): SD as ispiring objective for every member statein 2001 was approved the strategy for sustainable development in the European Unionimplementation at national levelA growing commitment to preserve environment, while making it compatible with both the social and economic development, exists at an international level. It is in this particular sense that the concept “Sustainable Growth” has been adopted as “that sort of development capable of satisfying the present needs without endangering the coming generations capacity to satisfy their corresponding needs” (Report of the United Nations Commission on Environment and Development, 1987).The Rio Declaration, approved in the United Nations Conference on Environment and Development held in 1992, introduced the term “Sustainable Development” as a principal element. The Conference also attached to this term a great political significance as it was supported by a solid set of Principles and an Action Programme that compound an operative framework for the development and instrumentation of a worldwide environmental policy. The European Union introduced the idea of sustainable development in the Treaty of the Union (art. 2) as an inspiring objective of every Member State for their social and economic regulations. In June 2001, The European Counsel of Gothenburg approved the Strategy for Sustainable Development in the European Union. In different countries, the governments have decided to promote this process through the preparation and starting national strategies on Sustainable Development.
17 Alternative materials in road construction important quantities of material from natural sourcesgradual degradation of the environment.adequate management of waste materialsgrowing concernEU waste policyinfluence in the national enviromental legislationpriority of re-utilisation and recyclingEN harmonised standardsreferences to the use of some alternative materials as aggregates in road constructionPublic works represent a fundamental factor for the impulse of development in every country. Technical considerations, as well as economic, social and environmental related ones, must be taken into account in the planning, design, construction and exploitation phases of every public work. Linear works, as a particular type of the public ones, usually show an associated environmental impact, as a consequence of their particular characteristics. In addition, this type of works requires important quantities of material mostly from natural sources –gravel pits and quarries- which cause a gradual degradation to the physical environment.On the other hand, a growing concern about the adequate management of waste material from the production –industry, agriculture and energy- and residential sectors exists nowadays at an international, national, regional and local level.The environmental legislations of the countries inside the EU are being adapted to the new perception of the waste material policy in the EU, contributing to the protection of the environment, coordinating the waste material regulations with the economic, industrial and territorial ones, stimulating the reduction of its generation and prioritising the re-utilisation, recycling and appreciation of the waste material over other management techniques.Based on Directive 89/106/CEE, new EN harmonised standards have came into force in the EU. Three of them are referred to aggregates for material used in road construction and make reference to the utilization of some alternative materials.
18 Recycling in Europe: OECD report 1997 The OECD (Organisation for Economic Co-operation and Development) report entitled “Recycling Strategies for Road Works”, published in 1997, basically presents a review of the status of recycling for road construction and rehabilitation up to The report was started in 1995 by a Scientific Expert Group of the OECD Road Transport Research Programme, as a follow-up activity to the 1977 OECD report entitled “Use of Waste Materials and By-products in Road Construction” that became an initial reference in the recycling sector.The report assesses the extent of current use of various by-products materials and waste management and recycling policies in Member Countries of the OECD. A part of the report includes a discussion on the finding on the use in road construction of four particular road by-products: reclaimed asphalt pavement (RAP), reclaimed concrete pavement (RCP), reclaimed base and subbase material (RAM), and mixed RAP, RCP and reclaimed base and subbase materials. The OECD Expert Group obtained this information from the replies to a specific questionnaire sent out in 1995/1996 to Australia, Austria, Belgium, Canada, Denmark, Finland, France, Japan, the Netherlands, Norway, Sweden, Switzerland, United Kingdom and United States.As shown in Table, a high amount of RAP is recycled in the surveyed countries, generally to produce in-plant and in-place hot mix asphalt (HMA) as well as cold-mix asphalt (CMA), stabilised and unbound bases, and fill. RCP is mainly used for unbound base, cement-stabilised base and fill in several OECD Member Countries. In Austria, the Netherlands and the United Kingdom RCP is also recycled as aggregate in Portland cement concrete.
19 Recycling in Europe: OECD report 1997 RAM is primarily used for cement stabilised base, unbound base and fill material. Reclaimed base and subbase materials are also used in cold recycling (in-place) with bituminous emulsion binder for uses as subbase and base course for light traffic . Old base courses can also be stabilised with Portland cement to increase bearing capacity .The mix of RAP, RCP and reclaimed base and subbase materials is used as stabilised base, unbound base or fill.
20 Recycling in Europe: OECD report 1997 As occurred for the case of road by-products, the situation on recycling of non-road by-products was analysed by the OCDE expert group based on the replies to the survey sent out in 1995/96 to OECD countries, responding the same 14 countries mentioned before.The non-road by-products analysed were those from metallurgical industry (steel slags, blast furnace slags and non-ferrous slags); coal fly ash and coal bottom ash/boiler slag; mine waste rock, mine tailings and quarry fines; scrap tyres; building demolition by-products; waste plastic and waste glass; and incinerator ash.The Table shows the level of use of each non-road by-product in road construction.
21 Changes in the European situation EU waste legislation and policydevelopment of the construction product directive (CD 89/106/CE)generalization of recycling road by-productsincorporation of new countries to the UE
22 Changes in the European situation EU waste legislation:framework legislationwaste framework directive (Dir.75/442/EEC)hazardous waste directive (Dir. 91/689/EEC)waste shipment regulation (C.Reg. (ECC) 259/93)waste treatment operationsincineration (C.Dir. 2000/76/EC)landfill (C.Dir. 1999/31/EC)recyclingwaste streamsdifferent directives (Related to: waste oils, titanium dioxide, sewage sludge, PCBs, restriction of hazardous substances, mining waste, etc.)The history of environmental policy in the EU began with waste policy to avoid the potential impact that a bad management of wastes could have upon the environment and human health.The Members States began taking national measures to control and manage waste, which then led to the Waste Frame Directive and the Hazardous Directive, both adopted in 1975, and later to the Waste Shipment Regulation. These three pieces of legislation put in place the basis of the regulatory structure on waste but did not specified the environmental emission parameter for the various waste management options that were considered to be acceptable: landfill, incineration and recycling.Most of these gaps were filled by the Landfill Directive, finally adopted in 2001, and by the Waste Incineration Directive of 2000; the stricter environmental standards introduced by both directives will to a certain extent promote the diversion of waste towards material recycling. Standards were set in terms of pollution into the air or into groundwater. In addition, the 1996 Directive on Integrated Pollution Prevention and Control (IPPC) sets standards for a number of waste-related activities, as well as for plants where waste can be used, as cement kilns.The 1996 Waste Strategy Communication from the European Commission reinforced the notion of a waste hierarchy (prevent, re-use, recycle, recover the energy and dispose), re-affirmed the “polluter pays” principle and developed the concept of priority waste streams.SOURCE: European Commission
23 Changes in the European situation EU waste new policy:Sixth environment action programmeadopted by EP&C in runs until 2012requires ec to prepare thematic strategies on seven areas:air pollutionprevention and recycling of waste (21/12/2005 com)protection and conservation of the marine environmentsoilsustainable use of pesticidessustainable use of resoursesurban environmentThe Sixth Environment Action Program (6th EAP), which was adopted by the European Parliament and Council in 2002 and runs until 2012, required the European Commission to prepare Thematic Strategies covering seven areas: Air Pollution, Prevention and Recycling of Waste, Protection and Conservation of the Marine Environment, Soil, Sustainable Use of Pesticides, Sustainable Use of Resources and Urban Environment.The Thematic Strategies represent the next generation of environment policy. They work with themes rather than with specific pollutants or economic activities and they take a long-term perspective in setting clear environmental objectives to around 2020 and will thus provide stable policy framework.Each strategy is founded in thorough research and science, and follow an in-depth review of existing policy and wide-ranging stakeholder consultation. They will help achieve the long-term goal of environmental sustainability while contributing to enhance growth and employment and to promote eco-innovation.SOURCE:European Commission
24 Changes in the European situation Development of CD 89/106/CEEU construction products directive 89/106/CEEharmonized en standardsorigin: EC mandates to CENmandatory character when referred to products and performance testsexisting on road pavement construction aggregates:EN 12620: Aggregates for concreteEN 13043: Aggregates for bituminous mixtures and surface treatments for roads, airfields and other trafficked areas.EN 13242: Aggregates for unbound and hydraulically bound material for use in civil engineering work and road construction.references to some alternative materialsThe main technical European piece of law in the area of construction finds its origin in the EU Construction Products Directive 89/106/CEE 21/12/88 dealing with the legal, statutory and administrative provisions of construction products in the Member States.The European Commission can establish “mandates” to CEN, during the legal development of Directive 89/106/CEE, requesting the elaboration of total or partially harmonized European standards that enable the free circulation of construction products. The harmonized parts of these standards present a mandatory character when referred to products and performance tests.In the area of road pavement construction aggregates three new harmonized standards have came into force in the EU :CEN (2002). EN 12620: Aggregates for ConcreteCEN (2002). EN 13043: Aggregates for bituminous mixtures and surface treatments for roads, airfields and other trafficked areas.CEN (2002). EN 13242: Aggregates for unbound and hydraulically bound materials for use in civil engineering work and road construction.These standards make an explicit reference to the utilization of air-cooled blast furnace slag (EN and EN13242), basic oxygen furnace slag (EN and EN13242) and electric arc furnace slag (EN and EN 13242) as an aggregate, indicating the corresponding specifications.In the actual version of the standards “recycled aggregates” are defined but additional requirements and specific testing methods for them are being developed to be included in the future as amendments.
25 Changes in the European situation Generalization of recycling roads by-products:great development of recycling road pavements in the last decadealternative to consider in pavement rehabilitationPIARC working grouphot mix asphalt recycling in plantcold in-place recycling with emulsion or foamed bitumenin situ recycling with cementthese techniques are considered as routine in many countries and are included in its specifications for highway worksIn the last decade a great development of recycling road pavement has taken place in many European countries. Recycling has became an alternative to consider in all pavement rehabilitation projects.Nowadays there are on-going works on pavement recycling techniques in PIARC (World Road Association) working in the elaboration of guidelines on recycling, basically in the following areas:Hot mix asphalt recycling in plant.Cold in-place recycling with emulsion or foamed bitumen.In situ recycling with cement.Cold in-place recycling with emulsion is being used to increase the structural capacity of pavements as well as to correct surface problems.In situ recycling with cement, with deep treatment between 20 and 35 cm, increases considerably the pavement bearing capacity correcting surface deformations at the same time.In many European countries these techniques are considered as routine and are included in its specifications for highway works. In addition, recycled asphalt pavement are being used in different percentage as aggregates in new hot and cold asphalt mixes.
26 Changes in the European situation Incorporation of new countries to the UE:1957 TRATIES OF ROME (6): Belgium, West Germany, Luxemburg, France, Italy and the Netherlands.1973 (6 to 9): Denmark, Ireland and the United Kingdom.1981(9 to 10): Greece.1986 (10 to 12): Spain and Portugal.1992 THE MAASTRICHT TREATY CREATED THE EU1995 (12 to 15): Austria, Finland and Sweden.2004 (15 to 25): Cyprus, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia
27 Situation in CEEC countries increase in mobility and goods distributionimprovement of the road networkpossibilities to recycling techniquesSAMARIS deliverable D15review of the situation of road and non-road by-products recycling in ceecsbased on a similar questionnaire to that of oecdcoordinators of the works:Brno University of Technology from the Czech RepublicRoad and Bridge Research Institute from Polandsurveyed countries (10):Belarus (BY), Bulgaria (BG), Czech Republic (CZ), Hungary (H), Poland (PL), Romania (RO), Russia (RUS), Slovakia (SK), Slovenia (SLO) and Ukraine (UA).With the opening up of Central and Eastern European Countries (CEECs), an increase in mobility and goods distribution has taken place in Europe. This situation demands an improvement of the road network that offers lots of possibilities to recycling techniques of old existing infrastructures.Inside the SAMARIS project deliverable D15 has presented a review of the current state of road and other industry by-product use in road construction and rehabilitation in the Central and Eastern European countries, as well as an assessment of the extent of current use of various by-product materials and recycling policies in these countries.The report was prepared on the basis of a similar questionnaire to that used for the elaboration of the OECD report “Recycling strategies for roadwork” in the year l997. Therefore some parts of the report are formally similar.The coordinators of the works were the Department of Roads of Brno University of Technology from the Czech Republic and the Road and Bridge Research Institute from Poland.The report was elaborated on the base of WP 6 questionnaire and the responses were received from the following 10 CEE countries: Belarus (BY), Bulgaria (BG), Czech Republic (CZ), Hungary (H), Poland (PL), Romania (RO), Russia (RUS), Slovakia (SK), Slovenia (SLO) and Ukraine (UA).
28 Situation in CEEC countries ProductApplicationBYBGCZHPLRORUSSKSLOUAReclaimed Asphalt Pavement (RAP)RAP/year (kt)-369050140300223010355Plant recycling %2080In situ recycling %100154011Stock %6586Landfill %5Reclaimed Concrete Pavement (RCP)200Plant recycling %4585As shown in this Table, reclaimed asphalt is generally used for the production of HMA (in plant and in situ). Some countries recycle the available amount of this by-product in new HMA. In this case RAP can be added either cold or hot. Several countries use both hot-mix and cold-mix technologies.Reclaimed concrete pavement is used for newly constructed cement concrete binder courses of rigid pavements. In several CEE countries it is mostly used in unbound base and cement-stabilised base courses.Reclaimed concrete pavement is also recycled as aggregate in Portland cement concrete pavement.
29 Situation in CEEC countries Recycling road-by productsConclusionsrecycling techniques are knownbetter situation in central european countriesonly one recycling method in some countriesoften do not exist appropiate specificationsroad authorities are not well informednew technologies introduced by private companies (trial sections)
30 Situation in CEEC countries recycling non-road-by productsCONCLUSIONSonly few by-products are widely used:blast furnace and steel slags (granular or stabilized bases, backfills and embankments)fly ash (stabilized bases and embankments)mining waste rock (embankments,landscaping and backfills)the use of other by-products are almost unkown.lack of funds for research in new technologieslack of interest from road authorities
31 How to improve the situation? Barriersvary from one country to otherexamples of barriersno difficulties for waste disposalenvironmental considerationsfinancial and economic reasonslack of adequate information on long-term perfomance of alternative materialslack of standard requirements concerning recyclinglack of knowledge of all potential applicationsTo improve the situation described in the previous slides that is not only representative of the Central and Eastern European countries, but also, in some aspects, of some countries belonging to the EU before 2004, a set of measures have to be taken.In principle, alternative materials should be an acceptable substitute for natural materials in road construction when they provide little or no loss in performance and have limited environmental and economic effects.The barriers to promote recycling vary from one country to other. In countries where raw materials are easily available o where there are no difficulties for the disposal of wastes, because landfill space is plentiful and there are no laws regulating it, the need for recycling and reuse is not felt as strongly as in other countries. A great barrier has been also the environmental considerations on the use of these materials. In countries where market introduction of new materials is done by the private companies, financial and economic barrier are the main reason that some alternative materials cannot compete with natural materials. The most common barriers are the lack of : adequate information on long-term performance of alternative materials, standard requirements concerning recycling and knowledge of all potential applications.SOURCE: OECD, 1997.
32 How to improve the situation? Solutions:increase and improve existing legislation:restrictive regulations:to reduce waste productionto control waste disposalencouraging sorting, recycling and reuseinclude the use of alternative materials in contractsincrease research and demonstration projectsincrease transfer of knowledge among countriesSAMARIS projectguide on techniques for recycling in pavement structuresTo overcome the possible barriers to a rational use of alternative material in road construction the following actions have to be taken (OECD, 1997):Increase and improve the existing legislation, with restrictive regulations to reduce the production of waste and to control its disposal together with additional legislation that encourages sorting, recycling and reuse.Specify and encourage the use of alternative materials in contract documents.Increase research and demonstration projects.Increase transfer of knowledge among countries.The works developed inside the Pavement Stream of SAMARIS are one more step in this direction. The “Guide on Techniques for Recycling in Pavement Structures”, deliverable D29 of the project, aims for increasing transference of technology in this issue.
33 The need for environmental assessment to promote sustainability Prof. Dr.-Ing. Klaus KrassRuhr-University Bochum
34 The need for environmental assessment to promote sustainability Work Package 4, entitled “Safety and Environmental Concerns in Material Specifications”, is a part of the pavement stream and primarily concentrates on addressing safety and environmental aspects in product standards.
35 The need for environmental assessment to promote sustainability Task 4.3 is entitled “Environmental Annexes to Product Standards”.The aim of task 4.3 is to make proposals how environmental sustainability requirements of road materials could be included in the European Product Standards for road materials in form of an annex.
36 The need for environmental assessment to promote sustainability Justification is derived from the goal of the European Commission to incorporate environmental requirements into the second generation of the European Product Standards for construction materials according to the essential requirement “Hygiene, health and environment”.
37 The need for environmental assessment to promote sustainability This subject was not a part of the mandates for the different construction materials that have been standardised so far.Therefore the present first generation of European standards for road materials does not include any regulations concerning environmental specifications.
38 The need for environmental assessment to promote sustainability In relation to the construction materials, the main focus of task 4.3 was on recyclable materials and industrial by-products which can be used as aggregates for unbound and bound mixtures.That means: For natural aggregates, the environmental compatibility is given by default. There is no need for further testing.
39 The need for environmental assessment to promote sustainability Concerning industrial by-products and recycled materials, it has to be ascertained whether very different experience has been gained with the application of these materials in different European countries. In any case, the requirements for these materials do vary significantly.
40 The need for environmental assessment to promote sustainability In addition to the input from WP 4, input has been derived from other Work Packages of this project, particularly from WP 3 dealing with the assessment of alternative materials.
41 The need for environmental assessment to promote sustainability Concerning recyclable materials, it was found to be advisable to deal not only with mineral construction waste but also to deal separately with bitumen-bound material (reclaimed asphalt) and with tar-bound materials.Tar, especially coal tar and other tar distillates, was used as a binder in the past in many European countries because its hazard was not so well known at that time.
42 The need for environmental assessment to promote sustainability According to EN , reclaimed asphalt is “asphalt, not containing tar, reclaimed by milling of asphalt road layers, by crushing of plates torn up from asphalt pavements or lumps from asphalt plates and asphalt from surplus production”.
43 The need for environmental assessment to promote sustainability However, there is no European standard for tar bound reclaimed road material which can be defined as:material containing tar, and possibly bitumen as well, that is reclaimed by milling of bound road layers, by crushing of plates torn up from bound pavements or lumps from bound plates.Due to higher air pollution by heating tar bound reclaimed road material, this material can only be used in cold mixed base layers and sub-bases with bitumen and/or cement as the binder.This application too needs further examination for environmental reasons.
44 The need for environmental assessment to promote sustainability Starting from the considerations discussed above, some typical drafts for environmental annexes to product standards have been developed, later on represented here by Sabine Boetcher.
45 The need for environmental assessment to promote sustainability Mandate M/ 366 of EC to CEN for Horizontal TCDevelopment of horizontal standardised assessment methods for harmonised approaches relating to dangerous substances under Construction Products Directive (CPD)Emission to indoor air, soil, surface water and ground water
46 The need for environmental assessment to promote sustainability The EC expects that the response to this mandate shall consist of a comprehensive package of technical reports and of measurement/test standards that are manageable and user-friendly for regulators, product technical specification writers, writers of ETA etc.
47 The need for environmental assessment to promote sustainability Therefore it is obvious that our proposals for annexes to the standards shall include no threshold values.That means for the time being:Provisions valid at the place of use can be used to assess the suitability of recycled or industrially produced aggregates.
48 The need for environmental assessment to promote sustainability Concerning our work, the hope remains that such environmental annexes will expand into the next generation of road product standards in order to enforce the safety and to promote the sustainability when dealing with industrial by-products and recycled materials.
49 General assessment methodology for best usage of alternative materials Denis FRANÇOISLaboratoire Central des Ponts et Chaussées - France
51 Natural resources saving IntroductionNatural resources savingGrowing pressure to use alternative materialsReduction of waste disposalBarriers remainPerception as « waste »Economic reasonsEngineering performancesEnvironmental effectsTechnical ConcernsShort to long termNatural resources saving, reduction of waste disposal, both induce a growing pressure to use alternative materials, notably in road construction. However several kinds of barrier remain to prevent an optimised recourse to these materials, should these barriers be social, economical, or technical. Among potential users, concerns exist regarding the actual engineering performances of these materials and regarding their effects on the environment; and this, from the short to the long term. Unfortunately, classical road design guidelines or standards are poorly adapted to answer to these questions.
52 Can we use this material here ? Engineering assessmentTo fulfil the same mechanical functionsBut very rarely inert React to external factorsEnvironmental assessmentLandfill/Construction: same physical & chemical lawsBut somewhat different conditions Different effects??Need for an assessment methodology for the re-use of alternative materials???The Assessment Methodology should be:Integrated: engineering + environmentGeneral: applicable to all alternative materialsRational: the right material in the right place???Questions from potential users are for example: Is this material able to serve in the surface course ? Or is it better to use it in the embankment ? If so and if leaching occurs, may this wood downstream be impacted ? If the release is even larger, may the river be polluted ? May this aquatic ecosystem be disturbed one day ? Is it better to use the material far from the river ? But then, if pollutants infiltrate into the soil, may the groundwater be polluted ? In such a structure, the engineering performances of the material are okay to undergo the present traffic, but if the traffic becomes heavier in the future, will the material face up ?Regarding engineering assessment of alternative materials, the principle to follow is that these materials must allow the road layer to fulfil the same mechanical function as traditional materials do. The problem is that oppositely to classical road materials, alternative materials are very rarely inert and they tend to react to the effects of external factors (thermal, chemical, physical). Regarding the environmental assessment, for few years, the knowledge related to the chemistry of many materials destined to landfill has progressed. For a given material, should it be destined to landfill or to re-use, the same physical and chemical laws apply. However the conditions that apply into a road structure are somewhat different from the ones that apply into a landfill, then different effects can be expected.These characteristics of alternative materials and of their field of implementation call for the development of a suitable assessment methodology. This methodology should be Integrated, General, and Rational.
53 Toward the Methodology with WP3 Context:Decisions:Time available: 2 yearsRecent knowledge progress on some materialsContemporary methodological efforts in neighbouring fieldsNo experimental programme, no testingReflection on a range of materialsTo make the most of the available knowledgeThe Assessment Methodology should be:Integrated:A multi-disciplinary group already aware of the recycling problematicGeneral:Some « rather known » materials for which a certain amount of knowledge was availableMaterials representing considerable production and stockpiles, thus stakes at European levelMaterials for which end users (road constructors and managers) had pressing questionsMaterials presenting a broad set of properties met among alternative materialsThe purpose of SAMARIS WP3 was to progress toward this Integrated, General and Rational assessment methodology. The context of such a project was that the time available to develop the proposal was limited to 2 years, but also that the knowledge related to some alternative materials had progressed in the previous decade, as well as similar methodological efforts carried out in neighbouring fields, in Europe and in the USA. Considering this context and the limited time available, the decision was taken to develop the reflection from a limited range of materials, to not programme any experience or testing, but to make the most of the recent knowledge progress regarding this range of materials and methodological efforts.A multi-disciplinary group was constituted with peoples already aware of the recycling problematic. These group gathered together competences in mechanic, leaching and eco-toxocity.In the time available, it was not realistic to plan for a fully General methodology. Materials chosen to develop the reflection were among those for which the knowledge available was great. These were also materials representing actual stakes at European level regarding production, stockpiles. The idea with these material range was also to provide answers in the short term, to some of the most pressing questions from end users (road constructors and managers). For perspectives at longer term, in order to provide a useful effort toward the development of the future general assessment methodology, those materials were also chosen in order to represent a broad set of properties met among alternative materials. Indeed, to be General, the assessment methodology has to proceed with properties only.The Rational aspect of the methodology was developed following the functional principle: Whatever the material, functional properties of the road structure have to be guaranteed. Thus, the relevance of a material for a given application can be judged on the basis of its actual ability to fulfil the road layer functions.Rational:The functional principle: Whatever the material, functional properties of the road structure have to be guaranteed
54 Interactions Material/Environment Structure reactions:Particle transfer/PloggingSolute transfer/PrecipitationBearing capy V°SwellingCracking…Structure reactions:ErosionRunoffInfiltrationCracking…Material reactions:Particle emissionDissolutionChemical reactionsSelf-binding/Stiffening….External factors:WindRainfallWetting/DryingCold/Hot T°Maintenance (winter, …)Traffic characteristicsDumping (chronic, accidental)…Targets:Living organismsSurface waters …Soil …Groundwater …A testing procedureAssessment ofrelevant properties… associated with acceptable Use scenarios- Local environmental conditions (prevailing external factors, environmental sensitivity)- The way the material is implemented (in relation to water notably)Oppositely to traditional road materials, alternative materials are rarely inert. They react to external factors and they have sizeable effects on the road structure and on the environment This explains the gap usually observed (for example in Alt-Mat) between the predictions made from laboratory tests’ results, and the field behaviour.External factors can be natural (wind, rainfall, etc…) or induced by the road use (maintenance operations, traffic characteristics, etc…). Depending of the way the road was built, its structure will react to these factors through erosion, runoff, infiltration, cracking, etc…. This will result in reactions at the material scale (particle emission, dissolution, chemical reactions, etc…). These reactions will induce different phenomena at the road structure scale: particle transfer or plogging, solute transfer or precipitation, swelling, cracking, etc... Then, emissions from the road structure can reach and possibly impact some natural targets (living organisms, surface waters, soils, etc…).As a consequence, for an alternative material, a rational assessment methodology should include a testing procedure - allowing the assessment of the strictly relevant properties -, associated with the definition of acceptable use scenarios describing the local environment most important conditions (prevailing external factors and environmental sensitivity), together with the way the material is planned to be implemented in the road structure.The assessment methodology:A limited set of Use-scenarios + A limited set of Tests
55 Ambition and limits of WP3 StorageProcessingTransportStorageLife CycleDemolitionTransportImplementationServiceA comprehensive assessment methodology procedure should cover the whole life cycle of the alternative material. However, the reflection developed in the context of SAMARIS WP3 only concerns the phases of implementation and service life, i.e. those phases during which the material has to fulfil the functional role of a road material and where, on-site, it has to face the usual external factors, should they be thermal, chemical or physical. That approach is of prime importance for end users as it directly concerns the mechanical durability and the environmental acceptability of roads.Effect of external factors on the material:Thermal, Chemical, PhysicalMechanical durability and Environmental acceptability of roads
56 Approach The road Structure: an open multi-layer system (Influence on not inert materials)Whatever the material, functional properties have to be guaranteedThe road Application: an essential element of the use-scenario(Application: a structural element of the road body)Defines the external factors to faceDefines the properties to respectFirst stage:Second stage:To identify the functional properties of each ApplicationTo list the properties of each Alternative MaterialThe road structure is an open multi-layer system into which external factors can influence the behaviour of not inert material. However, whatever the material used by the constructor, the functional properties of the structure have to be guaranteed in the course of time. In this multi-layer system, each part of the road structure (called Application), has a particular role to play, and is expected to be able to face certain external factors. The road application appears then as an essential element of the use scenario as it defines (i) a certain list of external factors to face, and (ii) a list of properties to respect for the material that will be used in this application. The first stage of the approach that was used in SAMARIS WP3 was thus to make explicit the functional properties expected to be fulfilled by each road application.This was done through a literature review and a survey among SAMARIS countries. The second stage of the approach was to list the known physical and chemical properties of each alternative material chosen for WP3. This explains the choice of « rather known » materials. Then the third stage of the approach was to assess the compatibility between the properties of each material and the expected functions of each application.Literature + Survey« Rather-known » materialsThird stage: Compatibility between Material properties & expected Functions
57 Road Structure and Applications Typical road structure (from COST 337 and FHWA) : 5 applicationsV Shoulders, landscaping, embankments5231VII BaseIII Sub-baseI SurfaceIV SubgradeThe way the material can be implemented: 11 Application cases… depends on Material properties, determines Interactions with the environmentApplicationsCasesUnboundBitumen boundCement boundII-a*I-bI-cIIII-aII-bII-cIIIIII-a-III-cIVIV-aIV-cVV-aIn order to be able to gather compare data from different countries, and in order to provide recommendations of interest for the different countries, a typical road structure comprehensible in all countries was first defined. This was done with reference to typical structures defined into projects with similar kinds of goals. Five different parts of the road body were thus defined (noted I to V). In addition to the application, another important element to consider is the way the material is implemented: unbound (noted a), bitumen-bound (noted b) or cement-bound (noted c). Indeed, this depends on the material properties (the ability and the necessity to be bound or not) and determines the material’s interactions with the environment (conditions of exposure of the alternative material to external factors). From an analysis of the usual practice regarding the way to implement materials in the different applications, 11 applications cases were defined. Application case I-a* (unbound surface course) is not a classical road use but it corresponds to the construction of tracks or uncovered car-parks for some specific light traffic situations and must not be neglected for some materials in specific contexts.
58 Materials and Properties Properties: 8 Materials (representative of: stockpiles, uses, issues)- Road crushed concrete- Building demolition crushed concrete- Coal fly ash- Basic oxygen furnace slag (LD)- Electric arc furnace slag- Crystallized blast furnace slag- Vitrified blast furnace slag- MSWI bottom ashRoadParticle sizeStiffening pot.Swelling pot.PetrographyPermeabilitySolubility pot.….BuildingIndus. By-prod.ResidueCompilation of materials’ properties:- International references- National literature reviews and databasesSamaris WP6 (Recycling Techniques across Europe)Working group own experienceMaterial properties sheetsA list of 8 alternative materials was chosen to serve as a basis for the development of the assessment methodology. They are among the most important stockpiles in Europe, and all together, they represent different uses of alternative materials in road construction, as well as most of the main issues related to these uses. They also represent a wide range of properties met among alternative materials. They also represent materials from different origins, from the road recycling to the pure residue. A compilation of these 8 materials’ properties was carried out from international references, from national sources and databases, from inputs of SAMARIS WP6, and from the SAMARIS WP3 group own experience. For each material, all this information was synthesised into a Material properties sheet.
59 Application-Material Table 8 Materials: Properties (phys., chim.)1234567812345678IabcIIIIIIVVUnadvisable / Possible use (+/- Conditions)TestsEl.ts Use Scenario IEl.ts Use Scenario II11 Applications cases : FunctionsEl.ts Use Scenario IIIEl.ts Use Scenario IVWith on one hand the list of functions to be fulfilled by each road application, and on the other hand the physical and chemical properties of each material, it was then time to cross information to assess the compatibility of the second with the first. This was done as follow. First, in relation to Material 1 characteristics, its use in Application case I-a is judged as Unadvisable or Possible (with or without particular use conditions). If the use is Possible, the way to assess the Material 1 for Application 1-a is defined. Considerations related to the use conditions provide elements to the definition of the Use Scenario for application I. Recommendations for Tests provide elements to the definition of an Assessment procedure specific to Material 1. For Material 1, the crossing operation is applied for each application-case, so that elements of use-scenario for each application (from I to V) are provided, and so that, at the end of the process, a comprehensive assessment procedure for Material 1 can be proposed. The operation is then carried out for all materials, so that 8 material-specific assessment procedures can be elaborated and each material provides inputs to all use-scenarios, from I to V.El.ts Use Scenario VAss.t P.re 1Ass.t P.re 2Ass.t P.re 3Ass.t P.re 4Ass.t P.re 5Ass.t P.re 6Ass.t P.re 7Ass.t P.re 8
60 Progression of WP3Development of a proposal for improving the integrated assessment of (some) alternative materials for their rational use in road constructionTask 1Task 2Review of the contemporary situationThe way the 8 materials are actually used and testedInternational developments in alternative materials assessment (tests, methods) at research and standardisation levelDevelopment of the assessment methodology(Materials & Properties) x (Applications & Functions)=Methodological proposalRelevance of pre-existing protocolsNeed for test developmentsMaterial for the methodDeliverable 4As a conclusion to this, the objective of SAMARIS WP3 was the development of a proposal for improving the integrated assessment of SOME alternative materials, for their rational use in road construction. SAMARIS WP3 was structured into 2 Tasks. The first one was dedicated to the review of the contemporary situation. The second one was dedicated to the development of the assessment methodology. The first step of Task 1 was to highlight how the 8 materials are actually used and tested in various European countries. Results are provided in Deliverable 4. The second step of Task 1 was to make a point on the international developments in alternative material assessment at research and standardisation levels. Information are compiled in Deliverable 9. On the basis of the approach previously described, Task 2 was intended to provide the methodological proposal. By the way it makes an assessment of the relevance of pre-existing test protocols, and logically, it expresses specific needs for new test developments. All these elements are provided in Deliverable 16.Deliverable 9Deliverable 16
61 The 8 Materials in different states Answers to a questionnaire: A – DK – E – F – SLO – S – NLStatus: Mostly considered through the European screen (classification and rules for wastes) – Importance of the European exampleMaterialRoad usesProduced in n statesCoal faAll applications (I to V)6MSWI baApp° V, subgrade, sub-base7BDC concreteRoad base, sub-baseRC concreteRoad base3BOFs, EAFs, CBFs, VBFsVaries greatly between states4,4,4,5Market: Shortage of supply sometimes (Coal fa, CBF slag, VBF slag, EAF slag) - ImportationMat. propertiesNational documentsExamplesEngineeringTechnical ones mainlyFew Management onesCoal fa, VBFsMSWIba, BDcc, Rcc (1)EnvironmentalGreat lackBOFs, EAFs, CBFs, VBFs (0)The situation regarding the way the 8 materials were used and assessed across Europe was tackled thanks to a questionnaire send to SAMARIS countries’ representatives. Answers were obtained from Austria, Denmark, Spain, France, Slovenia, Sweden and the Netherlands. It appears that, on the legal point of view, those materials are mostly considered through the European screen (and not through a specific national screen). This means notably that their classification and their rules of management are those of Wastes.The materials chosen for SAMARIS WP3 are used in many road applications (so that field experiences can be exchanged and can be beneficial for the whole community) and they are produced in many countries. The use of some of these materials can be so great that sometime shortage of supply can occur and some countries have to import. Regarding the kinds of documents that can be used by countries for the use and management of alternative materials, considerations related to the mechanical properties of materials are mainly treated under the strictly technical angle (mainly documents for Cfa and VBFs), and poorly under the angle of resource management (few examples with MSWIba, BDcc and Rcc). The survey highlight the great lack of documents related to the environmental properties (in the 7 countries, 4 materials have no document at all). Moreover, among the national documents listed, most deal with material characterisation and use conditions, but few with production. This highlights the downstream situation into which the road sector is positioned today regarding the alternative material production field.As a conclusion, the survey shows the variety of states’ technical toolboxes, based on the national experience, as well as the common benefit to expect from the exchange of experience. It justifies the attempt for an European synthesis while states indicate the importance of the European example regarding rules of management.Fields: Characterisation & use (+), Production (-) – Downstream situation of road useVariety of states’ toolboxes – Beneficial experience to others Justification for an European synthesis attempt
62 Road applications’ functions Answers to a questionnaire: A – D – DK – F – SConclusions complemented with a literature reviewApplicationsMain functions…… but alsoI - Surface courseResistance to traffic stresses, Traffic safety, Comfort, Resistance to erosion*Resistance to vertical load, Prevention of water infiltrationII - Road baseResistance to vertical load, Resistance to traffic stresses, Load distribution, Stiffness, Anti-frostAnti-frostIII - Sub-baseResistance to vertical load, DrainageStiffness, Anti-frost, Anti-capillary riseIV - SubgradeResistance to vertical loadV - Should. Lands. Emb.Drainage, Resistance to erosionApplications: linked to a range of functions rather than a single oneIn order to take stock of the functions expected of each road application, a second questionnaire was send to SAMARIS countries’ representatives. Answers were obtained from Austria, Germany, Denmark, France and Sweden, were analysed and complemented with a literature review. As a conclusion, road applications appear to be linked to a range of functions rather than to a single one. Some functions are expected from several applications. With these last elements, the set-up of the Application-Material table was then possible and the assessment of the compatibility of materials for the different application cases can start.To set up Application-Material Table:
63 Suitability matrix: Elts of Use Scenarios The Rule: 1 major drawback sufficient to advise against an Un-appropriate application (U-AC)PUn-appropriate ACPossible ACPPPPP(8 x 11) AC24 U-AC= 64 P-ACPPEng. U-AC : 21Env. U-AC : 1Eng.-Env. U-AC : 2This matrix is the result of the crossing process between Materials’ properties and Applications’ functions. The suitability of each material was judged with consideration of both Engineering and Environmental properties. The rule of decision was very simple and selective: a single major drawback was sufficient to advise against an Un-appropriate application case. Despite this rather conservative approach, of the 88 potential possibilities, only 24 Un-appropriate application cases were identified, most (21) due to pure Engineering considerations, and only one due to pure Environmental ones. The matrix highlights that some very interesting alternative materials can be used in almost all application cases. It also shows that some application cases can accept different alternative materials, putting the management of the resource into perspective.
64 Material Asst Procedures: BDcc Case Ass.t P.re 3Engineering Prop. BranchesLeaching Prop. BranchesAnother product of the Application-Material table was the definition of Material-specific assessment procedures. This diagram presents the assessment procedure elaborated for Building Demolition crushed concrete. Ellipses represent a testing protocol for a property of interest, and rectangle the inherent screening stage thanks to the confrontation of the test result to threshold values. Each Material assessment procedure provides the principle pattern of assessment of material (toward the different application cases for which it is a priori acceptable (see Suitability matrix). Indeed, very few threshold values are available today for many properties of interest. They can differ from a country to another. As far as possible in Deliverable 16 such threshold values were provided to illustrate the procedure, but due to the scarcity of references, this was not the objective of SAMARIS WP3 to recommend particular figures.From the initial stages of engineering properties assessment, the alternative material can be directed toward the assessment procedure for unbound applications (in green), cement bound applications (in blue) or bitumen bound applications (in red). Regarding bound applications, at the end of the process, once the mixture is designed, it can be assessed on the environmental point of view (leaching) under a monolith form of the designed mixture. Indeed, due to the on-site expected interactions with the environment, at laboratory stage it is particularly important to test the material under conditions representative of the actual conditions (this includes possible interactions between the material and the binder). Depending on the alternative material, different chemical parameters have to be controlled. Regarding unbound applications, the connection between the Engineering branch and the Leaching branch let more possibilities to the user. The leaching properties assessment can be carried out at an earlier stage. Sometime, some preliminary testing on controlling properties will be carried out before the granular leaching test. For a given material, should it be bound or not, chemical parameters to be controlled are the same. After this stage, the agreement to use the designed mixture or the unbound application can be expressed.
65 M.A.P.: Engineering P.ies Branches Building Demolition crushed concreteHere are detailed the different parts of the Material Assessment Procedure of Building Demolition crushed concrete. First, some preliminary tests on Soluble Sulphate and Organic content before the Grading and the orientation of the material toward the different branches of the engineering properties assessment for bound and unbound applications. Second, the branches dedicated to the assessment of the material for bitumen bound applications (II-b, as a filler or as an aggregate) and cement bound applications (I-c to III-c). Third, the branches dedicated to the assessment of the material for unbound applications (Ia to Va). For filler, the tests of the procedure are Amount of Fines, Voids Volume, Stiffening Power, Absorbing Capacity of Fines. For bound aggregates, the tests are Particle Strength, Surface Cleanliness, Particle Shape and Water Absorption Coefficient (for bitumen). For unbound aggregates used in application V, the tests are only Compactibility and Bearing Capacity. Regarding application IV-a, Particle Strength is the only additional test necessary. For other applications (I-a to II-a), tests are Particle Strength, Compactibility and Bearing Capacity, and Resilient & Permanent Deformation. For applications II-a and III-a, depending on the context of use, optional tests, respectively, Permeability and Resistance to Freezing and Thawing, can be necessary.
66 M.A.P.: Leaching P.ies Branches MSWI bottom ashEAF slagBD crushed concreteHere is detailed the Leaching Properties Branch of the BDcc assessment. For unbound applications, the Total Organic Content or the Loss On Ignition should be controlled, then the pH development and the Buffering Capacity. Then on the leachate produced thanks to a Granular leaching test, a range of elements belonging to Inorganic salts, Oxyanions and Organics, should be controlled. This last control should be done directly on the bound mixtureFor EAF slag, only the pH development should be necessary before the Granular leaching test. Elements belonging to Metals and Oxyanions should be controlled.For MSWI bottom ash, only recommended for unbound applications the Total Organic Content or the Loss On Ignition should be controlled, then on one side the pH development and the Buffering Capacity, and on the other site the Redox development. Then, on the leachate, a range of elements belonging to Inorganic salts, Metals, Oxyanions and Organics, should be controlled.
67 Toward a General Implementation MSWIba for III-aRcc for II-cBOFs for I-bIn the perspective of development of a General assessment methodology, once combined all together, as many of them use similar test protocols, the Engineering branches of all Material Assessment Procedures, provide this single testing procedure for 64 possible application cases (P-AC). As a matter of unbound application, one can see through which steps MSWI bottom ash will have to pass to be assessed as a sub-base material (III-a). As a matter of cement bound application, the example of Rcc that has to be assessed for the base course (II-c) is provided. These two cases have in common an assessment of the Soluble Sulfate. As a matter of bitumen bound application, the example of BOF slag that has to be assessed for the surface course (I-b) is provided. In such an application, the material can be used as an aggregate or as a filler. In the first case, it follows more or less the way previously described for Rcc, plus an assessment of the Resistance to Abrasion (for chipping) and of the Water Absorption Coefficient (peculiar to bitumen bound applications). In the second case, it follows another way: tests of the Amount of Fines, of the Voids Volume, of the Absorbing Capacity of Fines.64 P-AC
68 Test Methods for Engineering Pies 31 Tests for 64 P-ACEN standardsNo EN National standardsRPD routine ?PER standard ?Despite the general assessment procedure for engineering properties looks complicated, only 31 test protocols are used to cover the 64 Possible Application cases. Most of them are European standards. When no European standard exists, standards that are used at national scale and which protocols can be recommended, are proposed. In this list the European standard for the assessment of Resilient and Permanent Deformation is provided. However, this test protocol requires several days to be carried out and belongs more to the field of research than to the field of control. In the framework of the assessment methodology it is then not realistic to recommend it as a routine test. Adjustments around this protocol must then be sought for, either toward a simplification for a routine protocol, either toward the way the assessment of alternative materials is organised today. Regarding Permeability, no standard can be provided, and it is the protocol that was used in the Alt-Mat project that is recommended for the moment. The development of a standard for such an important property of alternative materials would be useful.
69 Main CasesMC 1MC 2MC 4MC 5MC 6MC 7MC 8MC 3Pre-testingIn the General assessment procedure for engineering properties, it is possible to identify some rather independent parts with specific series of common tests toward a range of applications. In the perspective of a higher level of integration of alternative materials’ assessment on the engineering point of view, this independent parts represent some Main Cases of assessment into which different materials can be considered equally. The degree of integration of this main cases varies a lot as some of them can consider 6 materials (MC3), while others only 1 (MC5). 8 MCs have been defined, plus a Pre-testing stage for some decisive properties.8 MC
70 Main Cases: Pre-testing MC 6MC 7MC 3Toward 9 Applications :- Surface course (a ; b ; c)- Base (a ; b ; c)Sub-base (a ; c)Subgrade (a)For 5 Materials:MSWI bottom ash- Building DC concrete- Road C concrete- BOF slag- Crystallized BF slagPre-testing concerns 5 of the 8 materials chosen for SAMARIS WP3. Depending on their usual properties, some of these materials will be tested to check their Chloride Content (Rcc for cement bound applications), their Swelling Potential (BOF slag for all applications), their Soluble Sulphate (MSWIba, BDcc, CBFs) for unbound and cement bound applications, their Organic Content (Rcc) for unbound and cement bound applications. Pre-testing is of importance for 9 application cases. Materials that pass this stage can be driven toward MC3, MC6 and MC7.
71 Leaching Prop. Branches Main Cases: MC3MC 3Toward 5 Applications :- Surface course (b ; c)- Base (b ; c)- Sub-base (c)For 6 Materials:- Coal fly ash- Building DC concrete- Road C concrete- BOF slag- EAF slag- Crystallized BF slagMain Case 3 is applicable to 6 materials concerned by 5 application cases: bitumen bound surface layer and base layer, and cement bound surface layer, base and sub-base. After Particle Strength assessment, materials with a potential to be used for chipping (BOFs, EAFs, CBFs) can even be assessed through Resistance to Abrasion. Then, all materials are assessed through Surface Cleanliness and Particle Shape. For bitumen bound application, only an additional assessment of Water Absorption Coefficient is necessary. Designed mixtures can afterward be assessed with regards to their Leaching properties.Leaching Prop. Branches
72 Leaching Prop. Branches Main Cases: MC6 & MC7MC 6MC 7Leaching Prop. BranchesToward 5 Applications :- Surface course (a)- Base (a)Sub-base (a)Subgrade (a)Embankments, shoulders… (a)For 6 Materials:- MSWI bottom ash- Building DC concrete- Road C concrete- BOF slag- EAF slag- Crystallized BF slagMain cases 6 and 7 are both entirely dedicated to aggregates for unbound applications (from I-a to V-a). They apply to 6 materials. For application cases I-a to III-a, Particle Strength assessment is first necessary, then Compactibility and Bearing Capacity assessment, and Resilient and Permanent Deformation. This concludes the procedure regarding application case I-a. For application cases II-a and III-a, depending on the context of use, optional tests, respectively, Permeability and Resistance to Freezing and Thawing, can be necessary. Regarding MC7, for application case V-a, only Compactibility and Bearing Capacity assessment is necessary do conclude the procedure. For application IV-a, only Particle Strength has to be tested previously.
73 Conclusions The Application: a decisive element of the use-scenario Engineering aspect: material properties application functionsLeaching aspect: form of the material (granular/bound, exposure) leaching propertiesEco-toxicity aspect: lack of data, difficulty to select among tests at that stage difficulty to include natural environment sensitivity in the use-scenarioCritical analysis of:Mechanical tests clarification (relevance)Suitability rationalization of the engineering approach: some practices should be avoided & management of materialsspecific needs: engineering, leaching, eco-toxicity assessmentThe reflection developed in the context of SAMARIS WP3 has shown the road application as a decisive element of the use scenario of alternative materials. First because regarding the engineering aspect, the alternative material properties have to fulfil the road application functions. This point is a priority for a safe and reliable use of alternative materials in road construction. Regarding the leaching aspect, the application dictates the form under which the material will be implemented (bound or not), and thus the conditions of exposition of the material to external factors. This has an impact on leaching properties of the road application. Regarding the ecotoxicity aspect, unfortunately the lack of data available today, and the difficulty to carry out a selection among the various existing test protocols, didn’t allow to propose any specific assessment procedure to the end users. Today it is even difficult to include the natural environment sensitivity in the definition of use scenarios.The approach developed in the context of WP3 was an opportunity to carry out a critical analysis of existing mechanical tests, allowing a clarification of their relevance with respect to alternative materials. The suitability analysis proposes a rationalization of the engineering approach of alternative materials in the field of road construction, it suggests that some practices should be avoided and indicates that in the future the management of the alternative material resource will have to be better organised in order to make the most of its global potential. The suitability analysis also highlights specific needs regarding engineering, leaching and ecotoxicity assessment.
74 ConclusionsDevelopment of an integrated, rational, general assessment methodology:Iterative process Field/Lab. « Rather known » materials = an implicit first experience feed backA first step: make the most of the available knowledgeMulti-disciplinary approach put into practice in SAMARIS WP3Complicated (?): 1 tree: 8 materials, 64 cases, 31 tests simplification (MC ?)Extension to a wider range of materials with additional propertiesThe further development of an Integrated, Rational and General assessment methodology lays on an iterative process between the field observations and the laboratory studies. The use of « rather known » materials in the context of SAMARIS WP3 represents an implicit first experience feed back in this process. In the time available, the idea was to make a first step toward the general methodology development, making the of the available knowledge. The multi-disciplinary approach necessary to develop an integrated assessment procedure was put into practice in the WP3 group. It has allowed the mixing of cultures indispensable to that kind of project. The general state of the methodology is not reach yet, although the methodology can look already complicated. In fact it covers a great number of applications cases, using only 31 tests. The simplification effort must be carried on and maybe the idea of Main Cases represents a track. The procedure must be extended to a wider range of materials in order to incorporate additional properties in the assessment process.
75 Acknoledgements The audience The Partners of SAMARIS WP 3: Danish Road InstituteSwedish National Road and Transport Research Institute - VTIDanish Hydraulic InstituteNetherlands Energy Research Foundation - ECNFrench National School of Public Works - ENTPERecycled Materials Resource Center (University of New-Hampshire)
77 Methodology for Environmental Impact Assessment Hans A. van der SlootECN - Environmental Risk AssessmentOle HjelmarDHI Water & Environment
78 Construction Products Directive Essential Requirement No3 on Health & EnvironmentRelease of Dangerous substancesMandate accepted by Standing Committee Construction on October 2004 and subsequently issued by EU DG TREN to CEN in early 2005BT176 prepared for a new CEN TC 351 with a first meeting of CEN TC 351 in April 2006 at MaltaStart of the horizontal standardisation work on:SamplingIndoor airImpact to soil and groundwaterrelevant for road construction
79 Scenario approach in judging impact Problem definition and test selectionEN 12920Expert system /databaseLab, lysimeter, field data collection, data management, data formatting, storage and retrievalAPPLICABLE TO:CONSTRUCT.MATERIALS,AGGREGATESSOIL,SLUDGE,SEDIMENT,WASTE,etcManagement Scenario Description – configuration, design specifications, infiltration, climatePhysical , chemical, biological propertiesData integration between fields and tests, modeling and verification against field datapH, L/S & time dependence - redox, DOC, EC, ANCRelease with timeGranular MonolithicPercolation related Surface areaSource term descriptionImpact evaluation subsoil and groundwaterJudgement and decision making; QC; Regulatory aspects; Treatment, Utilization, Disposal
80 Leaching tests in Environmental judgement Judgement of the application of materialsLimit valuesRelation lab-practice (Scenarios)ModellingDevelopment of criteria for regulationRegulationCharacterisation leaching tests(identification of mechanisms and processes)Accessibility of data:data base/expert systemQuality control of productsProduct improvementEfficient measurementsPrecision measurement dataProduct modificationMeasurement for verification
81 Conformity assessment in the CPD Main aim: avoid unnecessary testing and focus on the key issuesAssessment of construction products in view of CPD/ER No. 3WT-ProductsNon WT-ProductsNon WT-ProductsWT = Without testingWFT = Without further testingFT= Further testingWFT-ProductsFT-ProductsConformity Evaluation acc. to prescribed Conformity SystemConventionallyApproved MaterialsCE -marking
82 Basic characterisation tests CEN/TC 292 EN 12920Granular materialspH DEPENDENCE TEST : BATCH MODE ANCprEn or COMPUTER CONTROLLEDPERCOLATION LEACHING TEST (PrEN 14405)orMonolithic materialsTANK LEACH TEST (MONOLITH) and COMPACTED GRANULAR LEACH TEST.pH DEPENDENCE TEST : BATCH MODE ANCprEn or COMPUTER CONTROLLEDorChemical speciation aspectsTime dependent release
83 Processes in a Road Scenario Approach proposed in CPD to assess impact and to derive criteria similar to scenario approach in EU LFD Annex IIRoad stabilisation material (e.g.Precipitationalternative construction material)Road shoulder, soilTransportmechanisms:Surface run-offChemicalPercolationmechanisms:Solubility controlAdsorptionPhysical factors:Chemical factors:PermeabilitypHParticle sizeGroundwater flowBuffer capacityPorosityDispersionChemical form (speciation)Organic matterSoluble saltsRedox
84 Modelling release by percolation Construction materialPbH2CO3pHAlMgCaNaClSO4SoilFeCusolidAlsoliditerationsH2CO3solidCuInterface reactionsPortlanditeCalciteFerri-hydritePoint of compliance60 daysMgSiPbsolidCusolidCrBruciteTenoriteEttringite
85 ConclusionsToo simple approaches for addressing the complex issue of environmental impact evaluation in the long term leads to poor management decisionsA straightforward, scientifically sound and yet flexible framework covering many materials in various environmental settings is available (methodology approach versus material approach)A limited number of leaching tests can provide the crucial answers needed to assess long-term impact from a wide range of materials in a wide range of scenarios and life cycle stagesFor road materials this implies a pH dependence test and a column test for characterisation and a batch test for complianceThe approach presented for inorganic contaminants is equally applicable for organic contaminants as well as for radionuclides, whenever relevant
86 ConclusionsThe here proposed hierarchy in testing provides the necessary detail required by regulators and developers of treatment techniques, while at the same time it provides for cost effective compliance and QC testing for industry Chemical speciation using mineral solubility, sorption on mineral surfaces and interaction with dissolved and particulate organic matter provides identification of release controlling factors similar among widely different materials to solve problems of undesired release from materialsContrary to the current situation in the CPD recycling and "end of life" aspects of road construction materials should be considered under ER3 to ensure sustainabilityDevelopment of a European database/expert system for leaching and composition data to disclose inaccessible information from public domain research and avoid unnecessary duplication of work
87 Relevant InformationHOW TO JUDGE RELEASE OF DANGEROUS SUBSTANCES FROM CONSTRUCTION PRODUCTS TO SOIL AND GROUNDWATERTopic 1 - Soil and groundwater impactTopic 2 - Hierarchy in testing: Characterisation, initial type testing, further testing and selection of tests in specific stages of material judgementTopic 3 – Proposal for reference to ER 3 aspects in product standards and in CE markingDijkstra, van der Sloot, Spanka, Thielen ECN-CLeaching backgroundCEN Construction and CEN Environment Workshop - Coimbra, Portugal (Sept 2003)LeachXSDatabase/expert system for environmental impact evaluation:
89 Task 4.3: Prototype environmental annex to product standard Dipl.-Ing. S. BoetcherRuhr-University Bochum
90 Proceeding Activities on this task were subdivided into four steps: Identification of relevant road materialsIdentification of appropriate European Product StandardsIdentification of hazardous components and appropriate test methodsFormulation of draftsThe introduction to this task was given by Prof. Krass. So, the aim of this task was to draft annexes to product standards. The proceeding was subdivided into four steps.
91 Step 1 – Relevant road materials Differentiation betweenindustrial by-products e.g. municipal solid waste incinerator bottom ash andrecycled materials e.g. crushed mineral construction wasteDescription of the relevant materials together with the potential applications in road structureThe relevant materials were chosen as a result of a literature research and in consequence of the input given by other work packages. They were assigned to two groups. For each material the potential applications in road structure were defined.
94 Step 1 – Relevant road materials Recycled materialsAbbreviation1Crushed mineral construction wasteCMCW2Reclaimed asphalt pavementRA3Tar-bound reclaimed road materialTBThe relevant recycled materials are listed in this table.
95 Step 2 – Identification of appropriate European Product Standards Drafts to these selected typical standards for aggregates and their bituminous mixtures:hEN 13043hENhENDrafts to these selected typical standards for unbound and hydraulically bound materials :hEN 13242EN 13285Within this task these standards were chosen for getting and environmental annex.
96 Step 3 – Identification of hazardous components and appropriate test methods Scepticism about application of industrial by-products and recycled materials because of a potential danger less for the workers during the processing but especially for soil and groundwater in consequence of leachingExample: Decisive hazardous characteristics for MSWIBApH-value Chromium VIEl. conductivity Chromium tot.Chloride NickelSulphate CopperCyanide (e. p.) ZincDOC ArsenicAluminium AntimonyMolybdenum LeadCadmiumEN (Tank test)This slide exemplarily lists the decisive hazardous characteristics for MSWIBA which can be identified by a tank test.
97 Step 3 – Identification of hazardous components and appropriate test methods Example: Decisive hazardous characteristics for RA:SulphurPhenol indexPAH (EPA)Further potential hazard:Tar Detection of PAH (proposal WP 4)This slide lists the decisive hazardous characteristics for Reclaimed Asphalt (RA).
98 Step 4: Drafts of annexes to product standards Example 1:Environmental Annex to EN “Aggregates for bituminous mixtures and surface treatments for roads, airfields and other trafficked areas”(normative)With reference to the essential requirement “Hygiene, health and environment” of the Construction Product Directive (CPD) aggregates have to comply with the following specifications.For natural aggregates the environmental compatibility is on principle given. There is no need for further testing. The same can be assumed for boiler slag (BS).For recycled aggregates and industrially produced aggregates the hazardous characteristics according to table 1 and table 2 have to be determined.DraftOn the basis of an existing note in annex ZA this text is proposed as environmental annex.
99 Hazardous characteristic Hazardous characteristics to determine for crushed mineral construction wasteKind of determinationHazardous characteristicCMCWLeaching testpH − value(X)El. conductivityChlorideXSulphateChromium VIContent by massEOXHydrocarbons 1)PAH (EPA)PCDD 2)PCB 2)DraftThe following two tables show the hazardous characteristics which have to be determined.1) only hydrocarbons not originated from bitumen2) only if susceptible(X) values to determine only for information
100 Hazardous characteristic Hazardous characteristics for industrially produced aggregates to determine within a leaching testHazardous characteristicCBF slagVBF slagBOF slagEAF slagCFApH − value(X)El. conductivitySulphateXVanadiumChromium tot.ArsenicCadmiumDraftThe leaching test has to be carried out according to EN The content of PAH has to be determined according to ….Provisions valid at the place of use can be used to assess the suitability of recycled or industrially produced aggregates.
101 Step 4: Drafts of annexes to product standards Example 2: hENEnvironmental Annexto EN “Bituminous mixtures – Material specifications – Part 8: Reclaimed asphalt” (normative)With reference to the essential requirement “Hygiene, health and environment” of the Construction Product Directive (CPD) aggregates have to comply with the following specifications.For proving the sole existence of bitumen as binder in the reclaimed asphalt information about the construction of the road can be applied, i. e. files or documentation of the construction time, or former results of quality control. In case of doubts the content of PAH (EPA) shall be determined according to… and the phenol index after a leaching test according to ENDraftThe proposed environmental annex to EN is given as second example. The tittles hint at the fact, that the test method will have to be standardised.
102 Step 4: Drafts of annexes to product standards Example 2:Environmental Annexto EN “Bituminous mixtures – Material specifications – Part 8: Reclaimed asphalt” (normative)If a content of 30 mg PAH/kg of reclaimed asphalt and a phenol index of 0,1 mg/l is not exceeded, it can be assumed that the reclaimed asphalt doesn’t contain tar.In case of doubts the content of sulphur shall be determined and declared according to …DraftConcerning tar and sulphur this formulation is proposed in the annex.
103 Step 4: Drafts of annexes to product standards Handling tar-bound reclaimed road material:No present European standard!Content of PAH > 30 mg/kg TBLeave material in the roadRe-use in cold mixtures e. g. withbitumen emulsion or foamed bitumen and/or cement as binderDisposalTar-bound material should be handled in this way.
105 Health, Safety, Environmental assessment Procedures for identifying hazardous component materials for asphaltPresentation SAMARIS work package 4, report deliverable D23.
106 Project team Virginie Mouillet Laboratoire Central des Ponts et ChauséesFranceCliff Nicholls & Piouslin SamuelTransport Research Laboratory UKFrançois Deygout & Burgard KoendersCooperation:Laboratoire Central des Ponts et Chaussées in France,Transport Research Laboratory in the UKand Shell Global Solutions (France) S.A.S in France.
107 Interest in recycling Recycling in the asphalt industry since 1970s Proper recycling of road materialswith or without change in functionUse of initially non-road materialse.g. demolition concrete, tyres, glass, furnace slag, fly ashesSustainable development: whole life cycle (EAPA)Health, safety, environment: now and in the futureOptimising the use of natural resourcesPotential economic incentives to recycle/re-useThe asphalt industry has long been a supporter of recycling. Recycling began in the 1970s and has grown ever since. Reclaimed asphalt can be considered an engineering material.The European Asphalt Pavement Association (EAPA) recommends a useful distinction between recycling and re-use of asphalt depending on the change in the original function of the material. Recycling can be done in situ or a stockpile can be made and the material can be used in later productions.The asphalt industry is interested, but also careful, about the use of initially non-road materials.Examples are demolition waste, rubber from old tyres, glass, plastics from electrical wiring; and also materials from industrial by-products such as blast furnace slag, fly ashes.The EAPA, in 2004, has presented trends that show the interest in recycling and the use of alternative materials, namely:Developments that are sustainableMinimise the environmental impact by optimising the use of natural resources (virgin aggregates for example) and by reducing the dumping of re-usable materialThere can be economic incentives to encourage recycling and the re-use of materials for road construction.Procedures must be in place in order to deal with less ‘well-controlled’ materials than standard materials.In principle, materials should only be used if there are no short term and long term disadvantages, both for the workers, the general public and for the environment.The future recycling of the pavement should not be endangered. And, of course, the technical and functional requirements must be met at a competitive price.
108 Risk assessmentProcedures to deal with less ‘well-controlled’ materials than standard materialsIdentification of hazardous componentsNature and concentrationDegree of exposure (dose and duration)Occupational exposure to workers, publicImpact on air, water and soilAnalyses and risk assessment before starting recycling workCircumstances that influence the riskProcedures must be in place in order to deal with less ‘well-controlled’ materials than standard material.It is important to clarify the words hazard and risk.Hazard (danger) is a physical situation with significant potential for human injury or damage to the environment. Risk is the likelihood of human injury or damage to the environment from a specified hazard.The whole life cycle of the asphalt has to be taken into account. A proper risk management case must be carried out, which includes:identifying the hazard componentsexposure to workers and the publicimpact to environment (air, water and soil)assessment before starting the recycling work
109 Health, Safety, Environment Investigations:Presence of (coal) tarPresence of sulphurDust derived from pulverisation during milling off and crushingFumes arising from heating during mixingSpontaneous ignition during heatingLeaching (once in place)Reaction to fire in tunnelsThere are several hazardous materials that are well-known to have been used in old pavements and consequently present a risk during the recycling step.The most obvious one is coal tar. Coal tar was used in the last century and is now known to be carcinogenic.It is also important to consider, along the substance-specific hazard identification, the different circumstances that maximise the risk during the breaking up the old pavement and the use of the reclaimed asphalt, namely:dust coming from the pulverisation during milling off and crushingfumes arising from heating during mixingspontaneous ignition during heatingleaching as a result of contact with water (this will be the subject of a separate presentation)reaction to fire in tunnels (this will be subject of a separate presentation)The proposed methodology in a visual form can be seen in the poster session.In the rest of the presentation, the progress in setting up the methodology and the associated procedures is shown.
110 Presence of coal tar in road pavements Rather extensive use of coal tar until the 1980sHigh amounts of Polycyclic Aromatic Hydrocarbons16 PAHs are listed as priority pollutants (EPA list)some are well-known for their carcinogenic propertiesin particular Benzo(a)Pyrenekey: determination of PAHLimits in European countries are differentCoal tar was used as a binding agent in the last century. About 15 years ago, it was decided that only bitumen can be used for asphalt mixtures.The main reason for abandoning coal tar was its impact on human health due to its contents in carcinogenic PAHs and phenol. In coal tar the PAH content is 1000 to times more than in bitumen.16 PAHs are listed as priority pollutants by the Environmental Protection Agency. Some of them are well known as carcinogenic. Benzo(a)Pyrene is the main carcinogenic.The European waste material list (EURAL) has set a concentration limit: a reclaimed asphalt containing more than 0.1% of coal tar should be regarded as hazardous waste. Hot recycling is not allowed and in some countries it is permitted to rely on cold techniques.It is important to note that the definition of asphalt containing tar can differ from country to country because the limits in several European countries are different.Key is that the PAH concentration can be determined in a reliable and fast way. The method can then be adopted as a standard method on which the harmonised limiting values for materials can be based.A false identification of reclaimed asphalt as tar-containing material has an enormous economical consequence when its (re)use is restricted.
111 Screening methods for PAH PAK-marker sprayStain test with tolueneVisual detection: minimum 5%w of coal tar present in binderSemi-quantitative method: Thin Layer Chromatography (TLC) using fluorescence under UV lightThere are different tests available for the detection of the presence of coal tar. The choice of the method depends on the objective of the analysis (for example use in the field or use in the laboratory).The screening tests are quick and are qualitative field tests to detect whether coal tar is present. There are two main methods:PAK-marker test (spray)the staining test: a few drops of toluene on the surface of reclaimed asphalt debris on a piece of paper filter; visual detection achieved for 5% weight of coal tar present in the binder.These tests have a detection limit of only 5% by weight of the coal tar present in the binder. The reliability of the procedures is poor and there are doubts about whether the detection limits exceed restrictions set by legislation.In thin layer chromatography (TLC), the migration of PAH spots on a TLC plate is compared to standard solutions with known concentrations of PAH. The spots are detected by fluorescence under UV light (with a wavelength of 366 nm). However, the test does not provide information about the exact content of PAHs and, consequently, the detection limit can exceed restrictions set by legislation.The quantitative detection methods as vacuum sublimation, HPLC and GC-MS allow a precise, reliable and sensitive quantification of individual PAHs. However, such laboratory PAH analysis is expensive, time-consuming and requires well trained staff. Furthermore, they are not suitable as field measurement techniques.Quantitative methods: vacuum sublimation, HPLC, GC-MS
112 Research: fast and reliable method LCPC - test procedure within 6 hoursRecovered binders on TLC plate (separation)Precise quantification of individual PAHs by High Pressure Liquid Chromatography (HPLC)Detection limits2%w coal tar present in the binder(based on 5%w of binder in the asphalt mixture):about 260 mg PAHs / kg of Reclaimed Asphaltabout 8 mg BaP / kg of Reclaimed AsphaltLCPC carried out research to develop an approach combining a fast preparation of samples and a precise quantification of individual PAHs.The first step is to recover the binders from the asphalt.Then, a separation of components by thin layer chromatography is carried out.The individual PAHs are then determined by HPLC.The detection limits of this method were determined to be about 260 mg of PAHs per kg of reclaimed asphalt and 8 mg of Benzo(a)Pyrene per kg of reclaimed asphalt. These detection limits are essentially restricted by the PAHs isolation step. This can be further optimised in the future.The total test procedure can be carried out within 6 hours.The principle of the test is to apply along a horizontal line a weighed sample of recovered binder. Then, the TLC plate is placed in the chromatography chamber filled with a layer of carrying liquid (n-hexane/toluene mixture). This liquid will be adsorbed by the silica gel coating and pass the spots.After drying, the spots can be seen under UV light.The band of silica gel where the spots of PAH are identified in comparison with a PAH standard spot is scraped, removed and dissolved in a solvent mixture. The solution is analysed by HPLC.
113 Presence of sulphurSulphur as a substantial part of the asphalt mixture was used in road construction in 1970sSulphur is present in bitumen – however, as part of various molecular structuresLCPC - test method for total sulphur content in binder: emulsification and ICP-AES analysisFurther study:How sulphur present?HazardRisk assessmentSulphur as a substantial part of the asphalt mixture was used in road construction in 1970s.Bitumen contains sulphur – however, sulphur is present as part of various molecular structures.The main issue with the presence of sulphur is the potential release of H2S and SO2.It is very important to make the distinction that sulphur present in bitumen is very different from sulphur added to the asphalt mixture.LCPC developed a test method to determine the total sulphur content of the binder.Further developments are required to relate the presence of sulphur to the hazard and the risk.
114 Airborne particulates Shell Global Solutions studyDustinessAir samplingParticle sizesFor looking at hazards related to airborne particulates (such as dust and fumes), the following scheme is useful for a discussion.The parameters important for health effects are: the composition of the airborne particulates and gases, their particle size distribution and the level of exposure in terms of duration and dose.The characterisation of hazardous compounds released from reclaimed asphalt first requires collecting the materials. The collection of airborne particles in terms of (personal) exposure is commonly carried out in an actual, real-life, situation (working environment). These measurements allow comparisons with established occupational exposure limits (OELs). Usually, mineral and organic matters are separately quantified.However, it can be important to be able to make an analysis of any hazardous components before starting the recycling work. In relation to airborne particles, two laboratory routes, together with the personal exposure route, can be envisaged. These are presented in the slide. The first laboratory route is to take the fine particles of the reclaimed asphalt sample as obtained by sieving, e.g. the <100 µm or the <63 µm or the <75 µm fractions. An alternative laboratory route is to generate airborne particles and the collected particles analysed for hazardous components that can, in a real situation, increase the risk for exposure. Such a laboratory method is not an exposure test, but it is investigated as a potential test prior to reclaimed asphalt production and use.It is advantageous for occupational hygienists and process engineers to have information on the propensity of materials to produce airborne particles (“dustiness” of the material) so that risks can be evaluated, controlled and minimised.Dustiness is a relative term and the measurement obtained will depend on the test apparatus used, the properties of the dust and various environmental variables. The test and the variables therefore need to be closely specified to ensure repeatability and reproducibility.In principle, the “dustiness tester” consists of the following elements: dust generation section, dust transfer section, sampling section, size fractionator(s) and dust collection system.
115 Classification of airborne particulates The American Conference of Governmental IndustrialHygienists (ACGIH)Inhalable: respiratory tractThoracic: lung airwaysRespirable: gas-exchange regionACGIH/ISO/CEN health related sampling conventions, for Europe: EN 481PM100PM10PM5 PM2.5The American Conference of Governmental Industrial Hygienists (ACGIH) has classified the airborne particulates as follows (ACGIH, 1993):Inhalable particulate massMaterials that are hazardous when deposited anywhere in the respiratory tract including nose and mouth. Inhalable samplers were defined as having a collection efficiency of 50 % (50 % cut point) at 100 µm.Thoracic particulate massMaterials that are hazardous when deposited anywhere within the lung airways and the gas-exchange region. Thoracic samplers were defined as having a collection efficiency of 50 % (50 % cut point) at 10 µm and airborne particulates can have sizes up to 30 µm.Respirable particulate massMaterials that are hazardous when deposited in the gas-exchange region including the respiratory bronchioles and alveoli. The 50 % cut point is at 3,5 to 4 µm and airborne particulates can have sizes up to 8,5 µm.In the ACGIH/ISO/CEN health related sampling convention for aerosols, the three ranges are represented by curves in which the proportion collected is given as a function of the aerodynamic diameter in micron. For Europe, the relevant standard is EN 481 (CEN, 1993).No single method of dustiness testing is likely to represent and reproduce all the various types of processing and handling used in industry. Therefore, a number of dustiness testing methods are in use in different industries. Different methods use different test apparatus and measuring principles, and express results in different ways. Methods that do not separate the dust cloud produced into the three health-related fractions – inhalable, thoracic and respirable dust – can serve the needs of the manufacturing industry, but give limited information on the health hazard due to the dustiness of the material.
116 Physical, chemical analyses Total PM and benzene soluble matterPAH in airborne particlesVolatile organic compoundsFibresSilicaHeavy metalsHalogens, TOC, PAH in leachateGravimetryHPLC, GCMicroscopyX ray diffractionICPX ray fluorescenceWhere there is a requirement to investigate further the collected particulate matter (suspended or deposited), this investigation may be carried out by various physical means or chemical analysis techniques. Several analytical techniques and methods may be used to separate, identify and quantify contaminant species contained in reclaimed asphalt. There is no single preferred approach: each is useful for specific applications.
117 Spontaneous ignition TRL study Screening Quantitative detection Direct combustion testCalorific value testingMicrowave testsQuantitative detectionCombustion susceptibilityRamped basket testAerated powder testMany countries have identified combustion problems associated with contaminated land and produced guidelines to avoid combustion.Spontaneous combustion occurs when the temperature of a material increases until it reaches its ignition temperature, without drawing heat from the surroundings.Ramped basket test:The sample material is placed in a wire mesh basket and suspended in a standard laboratory oven operating up to 400 ºC at a rate of 30 °C/h. A thermocouple is placed in the centre of the sample to monitor the temperature (at 20 s intervals). The change in sample temperature with time is recorded.
118 Spontaneous ignition TRL study: ramped basket test The temperature of oven and the sample, collected at specified time intervals (20 s), are plotted in the Figure.The samples (in this case porous asphalt samples) ignited at a temperature above 380 °C and reached peak temperatures between 100°C to 200°C above the peak oven temperature.An up-to-date review of literature reveals that national documents providing guidance on the use of colliery spoil within a pavement and laying of roads on contaminated lands are currently available. The ramped basket test results also indicate that the occurrence of a fire at a temperature less than 300 °C is highly unusual. Therefore, there is no need to insist that the ramped basket test has to be seen as a mandatory test. However, where the potential is high for spontaneous combustion, it is recommended to use this test as a screening test because the test can indicate whether such a material can undergo self heating or not and, thereby, minimise the occurrence of a fire hazard.indication of self heating
119 Final commentsFinding a potential hazard should not necessarily mean that the relevant component material cannot be used in asphaltDepending on the nature and extent of the hazard, the appropriate actions need to be defined: risk managementThe use of secondary component materials and recycling in the production of asphalt generally results in no exceptional hazards for operatives, the general public or the environment. However, the wider use could mean that the use or reuse of some non-standard materials may have health and safety implications. In order to encourage the acceptance of the routine assessment of materials to prevent that possibility, a procedure has been developed and the series of test methods needed for that procedure have been identified and defined.The test methods are to identify:The presence of coal tar.The presence of sulphur.The presence of airborne particulates, including condensed vapours.The potential for spontaneous ignition at maximum temperature.The potential for leaching.The reaction to fire.It is envisaged that the proposed procedure should be used for type testing possible new component materials and/or combinations of components. It is not envisaged that the procedure will be part of the mix design procedure for routine mixtures. In the unlikely event that a potential hazard is identified, that hazard should not necessarily mean that the relevant component material cannot be used in asphalt, just that appropriate precautions should be taken. An important feature of the procedure is that analyses and risk evaluations can be made before starting the recycling work.
121 Reaction to Fire Performance of Pavement Materials Dr. Sarah ColwellBRESarah ColwellBREBucknalls LaneGarston. WD25 9XXUKT: +44(0)
122 Background Reaction to Fire An essential requirement under the CPD contribution to the fire scenario.An essential requirement under the CPDClassification - EN : 2002The reaction of pavement materials to fire is an issue raised in the EU Mandate 124 for Road Construction Products.Reaction to fire tests can be used to determine: whether materials take part in a fire, whether they contribute to flame spread, their tendency to propagate flame and their potential to alter the thermal environment (i.e. preheating)The reaction to fire performance of products is classified using the parameters set in EN : 2002, in this case, using the provisions for flooring products and the following test standards.A1fl EN ISO 1182: 2002 (non combustibility) andEN ISO 1716: 2002 (Bomb Calorimeter)A2fl EN ISO 1182: 2002 (non combustibility) orEN ISO 1716: 2002 (Bomb calorimeter) andEN ISO : 2002 (Spread of flame test – flooring) 30 minutesBfl EN ISO : 2002 (Spread of flame test – flooring) 30 minutesEN ISO : 2002 (Small flame test) 15s exposure periodCfl EN ISO : 2002 (Spread of flame test – flooring) 30 minutesDfl EN ISO : 2002 (Spread of flame test – flooring) 30 minutesEfl EN ISO : 2002 (Small flame test) 15s exposure periodFfl No performance determined
123 Stage One Survey of MS Regulators and interested parties Incidents involving pavement firesReview Reaction to Fire test methods availableQuestionnaires were sent to regulators and interested parties asking for their experience and views on the this subject.Literature reviews and web searches were used to look for incidents where pavement material was identified as playing a role in the fire propagation.Reaction to Fire review included 12 different flooring and radiant panel based tests currently in use throughout the world. The use of fire resistance test methods was also considered.
124 Findings from Stage One No specific Regulations or requirements.Some requirements for tunnel lining materials.Many expressed an ongoing interest in the area.A review of incidents did not identify pavement material as adding a significant hazard to this type of incident.Heat fluxes typically twice standard RTF tests.No specific Regulations or requirements, relating the reaction to fire performance of pavement material could be identified but a number of countries specified requirements relating the fire performance of lining materials for tunnels and many expressed an ongoing interest in the area.A review of incidents involving vehicle fires did not identify pavement material as adding a significant hazard to this type of incident.As part of the findings from this work it was noted that in an open environment, heat fluxes at around 25 kW/m2 may be found for burning cars, typically twice that observed in many of the standard reaction to fire flooring tests, where the maximum imposed radiant heat levels is approximately kW/m2.
125 Stage Two Investigate the response of typical pavement material to : EN ISO (Current CPD flooring fire test)ISO (Cone Calorimeter test)From the literature review a typical vehicle fire scenario was found to impose a heat flux of around 25 kW/m2.The maximum imposed radiant heat level in the EN ISO test is approximately 11 kW/m2.The response of a specimen to a range of radiant heat exposure conditions (0 – 100 kW/m2) can be achieved using ISO , the cone calorimeter method.This test method was chosen as a means of quantifying the changes in the reaction to fire performance parameters of the three test samples.
126 Pavement MaterialDense Bitumen Macadam60/20 Porous AsphaltMastic AsphaltThree examples of road pavement materials were identified for investigation, all were manufactured with relatively high levels of organic binder.
127 Flooring Test - EN ISO 9239-1 Measurements: Flame spread Smoke Findings:No sustained ignition outside measuring zoneNo sustained flame spread outside measuring zoneNo differentiation of product typesThe test specimen is placed in a test chamber in a horizontal position directly below a gas‑fired radiant panel, inclined at an angle of 30°. The radiant panel produces a graduated heat flux over the length of the specimen. A pilot flame is applied to the hot end of the specimen to ignite any volatiles evolved. Once and if ignition occurs, the horizontal progression of any subsequent wind-opposed flame spread is record in terms of the time it takes to spread to defined distances. The test is terminated at thirty minutes or when flaming extinguishes, whichever occurs first. The results are expressed in terms of flame spread distance versus time, the critical heat flux at extinguishment.The test specimens used in this study were 1025 mm long by 225 mm wide and were representative of the product in its end use. The specimens, which were made up of blocks measuring 225 mm-wide by 305 mm-long by 50 mm-thick.
128 Cone Calorimeter – ISO 5660-1 Measurements:Heat Release RateSmokeMass lossIrradiance levels:35 and 50 kW/m2Findings:Critical Flux range kW/m2Differentiation based on THR - 24/54/87 (PA/MA/DBM) MJ/m2This test method is based on the observation that, generally, the net heat of combustion is proportional to the amount of oxygen required for combustion, i.e. approximately 13.1 MJ of heat are released per kilogram of oxygen consumed. The test specimens are burned under ambient air conditions, while being subjected to a predetermined external irradiance, and measurements are made of the oxygen concentration and the exhaust gas flow rate. The test method is used to assess the contribution that the product under test can make to the rate of heat released during its involvement in a fire. These properties are determined on small representative specimens.The test apparatus consists of a cone-shaped radiant electrical heater, a load cell, a hood and duct system and gas analysis and mass flow instrumentation. The operational part of the heater consists of an electrical heater rod wound into the shape of a truncated cone. The heater is capable of producing an irradiance on the surface of a specimen of up to 100 kW. The sample holder is placed on a load cell beneath the cone heater. A spark igniter is used to ignite the volatiles generated by the exposed specimens.The specimens were representative of the product and were square with sides measuring (100) mm. The thickness of the specimens was nominally 50 mm.This study has shown that the critical heat flux required to achieve sustained flaming when measured on the cone calorimeter was found to be 22 kW/m² for dense bitumen macadam, 21 kW/m² for mastic asphalt and 28 kW/m² for porous asphalt. This is typically twice the level of irradiance provided in the EN ISO flooring test. Differentiation between products was also observed based on total heat released from the specimens with an irradiance level of 50kW/m2:Porous Asphalt MJ/m2 Mastic Asphalt MJ/m2 Dense Bitumen Macadam MJ/m2
129 Summary of Findings (1)The cone calorimeter test can discriminate between pavement materials.Since EN is primarily reliant upon EN ISO to provide discrimination between classes Bfl and Dfl all three pavement materials have the potential to achieve at least a Bfl classification.The cone calorimeter test, ISO , has been shown in this study to provide an effective means of discriminating between the reaction to fire performance of pavement materials.The EN classification system for flooring products is primarily reliant upon EN ISO to provide discrimination between classes Bfl and Dfl. The results show that, for the products investigated in this study, this test method does not provide any differentiation in fire performance. Based on these results, all three pavement materials have the potential to achieve at least a Bfl classification.
130 Summary of Findings (2)The critical flux values for the pavement materials are typically higher than other flammable materials present in a road vehicle.In a confined area such as a road tunnel, the heat flux radiated back from the hot smoke layer and the tunnel walls would higher than in an open environment.The data from this study could enhance current modelling studies of fire and smoke issues in transport infrastructure scenarios such as tunnels.The critical flux values measured for the pavement materials are considered reasonably high in relation to the other flammable materials present in a road vehicle, it is therefore suggested that products such as the car’s tyres and interior would become involved at an earlier stage and would make a larger contribution than the pavement material itself.In a confined area such as a road tunnel, the heat flux radiated back from the hot smoke layer and the tunnel walls would increase the probability of the pavement igniting and making a more significant contribution to the fire growth than in an open road scenario.
131 Erik Nielsen Danish Road Institute Part 2 : Mechanical Assessment Towards functional specification irrespective of type of material (Modelling)Erik NielsenDanish Road InstituteWe are now ready to continue Part 2 of the parallel session ”Premium pavements from alternative materials for European roads”.My name is Erik Nielsen and come from the Danish Road Institute under the Danish Road Directorate. I will be chairman of this morning session on ”Mechanical assessment” and the achievements in prediction modelling of one of the important mechanical aspects in road construction, namely permanent deformation. The understanding and prediction of permanent deformation will be an important step towards functional specifications.
132 Mechanical assessment for models Towards functional specificationsAlternative or recycled materialsVirgin materialsEmpirical andrheologicalmodelsFunctionalengineeringpropertiesWhen the ultimate goal is functional specifications it is natural as far as possible to focus on functional engineering properties of the materials for the road.If we succeed in using performance based rather than performance related tests for input values to the models we will also gain the advantage that the input parameters will be ”blind” to the origin of the constituents.From this basic knowledge empirical and rheological models will perform just as well if the materials are based on alternative, recycled or virgin materials. Here we use empirical and rheological as indications of the level of sophistication of the models.
133 Mechanical assessment Modelling permanent deformationDeliverable 28Bituminous materialsUnbound granular materialsModelling of permanent deformation is important for the whole pavement structure, but due to the different nature of the materials models have been developed for the unbound granular materials and the bituminous materials.For the lower part of the pavement you will find the documentation in the SAMARIS project Deliverable 27.and for the bituminous bound materials you will find it in project Deliverable 28.Deliverable 27
134 Unbound granular materials PresentationsUnbound granular materialsPierre Hornych, LCPC, FranceBituminous materialsRonald Blab, TU Vienna, AustriaImplication for standardisationCliff Nichols, TRL, United KingdomPresentations of the models for the different materials will be performed by Pierre Hornych, LCPC, and Ronald Blab, TU Vienna respectively. And Cliff Nichols, TRL, will then highlight some special implications for European standardisation.
135 Implications of asphalt deformation results for Standardisation Dr Cliff NichollsTRL, UK, & CEN TC227/WG1/TG2
136 Contents Current position of CEN standards Test Results Obtained Wheel trackingCyclic compressionPossible DevelopmentsConclusions
137 Current Position of Standards Asphalt “package” to be implemented in 2008Test methods, EN 12697, already publishedMaterial specification and quality documents, EN 13108, to be published in 2006CEN MarkingWill be required to sell asphaltSingle test method for each situationMultiple tests only permitted if identicalEquivalence not assumed for adjacent situationsIdeally most appropriate test selectedThe “package” of EN and EN are the responsibility of CEN TC227/WG1. The package consists of 43 test methods, all of which have already been published, as parts of EN 12697, plus eight material standards and two quality standards as parts of EN Only one part of EN 13108, on reclaimed asphalt, has been published, but the remainder should be published shortly so that the common date of withdrawal of all equivalent standards can be set as the Christmas/New Year holiday in 2007/2008.When implemented, the harmonised standards will have greater status than national standards in most countries. Because of the Construction Products Directive and the Public Procurers Directive, suppliers will have to be CE marked to put it on the market. Even in those countries that do not require the CPD directly, the PPD will require all public procurers (the majority of clients) to demand a CE Mark. In order to make CE Marks comparable, a unique test, with all the parameters defined, is need for each situation. Multiple tests can only be permitted if the tests produce identical rankings so that that the results can be converted if not numerically equal. If there are different situations, theoretically the tests for each situation do not have to produce equivalent results, even at the boundaries. The tests do not have to be the most appropriate as such, but ideally there should be a logic in their choice, and the logic should be the best available.
138 Current Position of Standards EN : Wheel trackingLarge size devicesExtra large devicesSmall size devices, Procedure A in airSmall size devices, Procedure B in airSmall size devices, Procedure B in waterEN : Cyclic compression testTest method A — Uniaxial cycling compression test with confinementTest method B — Triaxial cyclic compression testThe test methods on deformation resistance are EN , Wheel tracking, and EN , Cyclic compression. Wheel tracking is a simulative test that is categorised as performance-related whereas cyclic compression is regarded by many people as being more fundamental and therefore is categorised as performance based.Because the tests are an amalgam of the best of the national standards from across Europe, the simulative tests tend to include several options because there is often no clear rational for the choice between them. In the case of the wheel-tracking test, there are five basic options, although the equipment for the last three have been made identical other than the ability to condition the samples in air and/or water. Although the basic concept is the same for each of the options, the measurement units vary between them which makes comparison difficult.The fundamental methods, such as cyclic compression, should allow for more rationalisation. However, the more fundamental this test becomes, the more parameters are involved. Therefore, two options are allowed, the uniaxial test where the confinement is produced by the upper platen being smaller than the sample so that the unloaded outer part of the specimen confines the inner part.
139 Current Position of Standards EN , Asphalt concreteEN , Asphalt concrete for very thin layersEN , Soft asphaltEN , Hot rolled asphaltEN , Stone mastic asphaltEN , Mastic asphaltEN , Porous asphaltEN , Reclaimed asphaltEN , Type testing of asphalt mixesEN , Factory production controlThe first seven parts of EN contain the requirements for the different material types. For each property, they give the test methods that are appropriate to measure it for the material. However, even if the test does not contain different options, it can contain other options (temperature, load, duration, etc) that are defined in EN 13108, type testing. Each of the material standards needs to read in conjunction with both the type testing and factory production control standards.
140 Current Position of Standards EN Test conditions for wheel-tracking testRef.DeviceCond.Temp. oCTest duration cyclesEN 13108-1-4-5D.1.2Small device, procedure AAir451000—XD.1.360D.1.4Small device, procedure B10000D.1.550D.1.6D.1.7Large device30000D.1.83000D.1.9D.1.10The wheel-tracking test is called up by three of product standards - EN , asphalt concrete, EN , hot rolled asphalt and EN , stone mastic asphalt. However, there are several options for each standard. Most of the options are in terms of test temperature, but both asphalt concrete and stone mastic asphalt allow both the small scale device and large device depending on the maximum loading for which the pavement is designed.
141 Current Position of Standards EN Test conditions for cyclic compression test(for EN only)Ref.CourseCond. temp.Test temp.Confining stressAxial loadFrequencyPulseD.2.1Surface15 °C50 °C150 kPa300 kPa3 HzHaversineD.2.21 s/1 sBlockD.2.3Base & binder40 °C50 MPa200 kPaD.2.4The cyclic compression test is only called up for asphalt concrete. However, there are also two options for both surface course and base/binder course mixtures.
142 Test Results Obtained Tests @ 50 oC / 60 oC Large Size Small Size in airSmall Size in waterRutting(%)Slope(mm/10³ cycles)LAVOCSurface6,0 / 7,60,102 / 0,2426,3 / 14,40,200 / 1,11611,2/35,5Up. Base3,0 / 5,00,036 / 0,0613,0 / 4,60,084 / 0,0603,4 / 3,3Low. Base–0,042 / 0,0030,8 / 2,70,016 / 0,0022,0 / 1,8DRI4,0 / 4,20,111 / 0,12511,9/21,93,11 * / 16,75 *144*/836*Binder10,5/16,20,092 / 0,3605,2 / 16,90,174 / 0,7727,5 / 24,0The wheel tracking tests were undertaken at both 50°C and 60°C. The results for 50°C are generally less than those at 60°C although for very stiff mixtures when the results are similar to the precision of the tests, the reverse can appear to be the case (as for LAVOC lower base material in the small size device with conditioning in both air and water). As can be seen, each test does rank the various materials with noticeably different values, but not in the same order for each test.* Calculated value because deformation reached 20 mm before cycles
143 Test Results Obtained Unconfined Strain after 3600 cycles Triaxial @ 40 oC@ 50 oCLAVOCSurface1,6 %6,6 % *–2,1 %Upper base0,78 %0,88 %DRI12 % *45 % *2,6 %12 %Binder1,7 %2,5 %1,5 %The cyclic compression tests were undertaken at both 40°C and 50°C. Again, the results at the higher temperature are greater than those at the lower temperature. However, the rankings from the options are reasonably consistent.* Calculated value because strain too great before 3600 cycles on one or more samples
144 Test Results ObtainedRatio of Small Size in air to Small Size in water50 oC60 oCSlopeRuttingLAVOCSurface0,510,560,220,41Upper base0,430,891,021,40Lower base2,630,391,501,48DRI0,040,080,010,03Binder0,530,690,470,70Ratios (ex. DRI surface course)SS air/SS water from 0,22 to 2,63SS water/SS air from 0,38 to 4,61Of the wheel tracking tests, the only difference between options is the medium used to control the temperature. Therefore, the results should be almost identical if the mediums do not affect that results. However, when comparing the results as a ratio of the results, the ratios vary between 0.22 and 4.6 rather than being around unity after ignoring the DRI surface course results, which appear to be outlier ratios. With the ratio as the result in air over the result in water, the ratios lie in the range of 0.22 to 2.63 whereas, with the ratio as the result in water over the result in air, the ratios lie in the range of 0.38 to The effects of water could be to cure the specimen, increasing the deformation resistance, and stripping of the asphalt, reducing the deformation resistance. Given that the results in water were greater than those in air, the detrimental effect was greater than the curing effect, even though no stripping was observed.Despite countries that previously used water cooling wishing to make both approaches equivalent provided there was no evidence of stripping, the results cannot support that equivalence.Effect of waterCuring to give better resultStripping to give worse result
145 Test Results ObtainedRatio of inverse of result to inverse of “best” result for test methodIn order to compare the rankings produced by each method, the inverse of the results are used so that the higher values are the “best”. The results are the normalised by division by the largest inverse result for the method. Therefore, all the results are between one (best) and zero.The results of the wheel-tracking tests at 50 oC show that DRI surface material is the most deformation resistant according to the large size device method whereas it is generally the least deformation resistant according to the small size device methods. The results of the wheel-tracking tests at 60 oC show a similar dichotomy.
146 Test Results Obtained Previous studies found rough equivalence Large size device results counter to small size device resultsDRI surface course mixture good deformation resistance rather than badBoth tests in specificationsCyclic compression support small size devicesPrevious studies had shown a general equivalence of the two pieces of equipment when the small device is used with air conditioning. In particular, there was a pre-normative programme organise by Jacques Bonnot and involving French, UK, German and Danish laboratories that did not find a similar conflict.Nevertheless, the overall conclusion from these results is that the large size device results are counter to the small size device results. In particular the DRI surface course mixture showed good deformation resistance rather than bad as it did with the small sized device. However, both tests are in the European specifications for CE marking. The cyclic compression results support the findings with the small size devices
147 Test Results Obtained Factors affecting deformation resistance the angularity of the aggregate particlesthe frictional properties of the aggregatesthe grading of the aggregatethe voids content of the mixturethe binder content of the mixturethe viscosity of the binderWhich explain different rankings?If there are inexplicable differences, then there must be some reason. The factors that are assumed to influence the deformation resistance of an asphalt include the angularity of the aggregate particles, the frictional properties of the aggregates, the grading of the aggregate, the voids content of the mixture, the binder content of the mixture and the viscosity of the binder. However, there is nothing obvious that can explain the differences, so which one (or more) are part of the explanation.
148 Possible Developments ResearchCorrelate test results with site experienceDifficultThe ideal – if good correlation foundIdentify test parameters causing differencesEven more difficultRelate differences to physical situationsBoth options expensiveFinanciallyIn timeTherefore, more research is needed (but I would say that, wouldn’t I?).The first aspect needing research is to correlate the test results with site experience for the material demonstrating the difference in order to find which test actually reflects reality. However, such research will be difficult, even if it is the ideal if a good correlation is found.The second aspect is to identify the test parameters that cause the differences in the ranking. However, such research would be even more difficult than the correlation with site data. The results would be useful to relate the differences to physical situations so the appropriate method can be used for different site conditions.Both options will be expensive, both financially and in terms of the time required to complete it.
149 Possible Developments StandardsAdministratively acceptableOne situation, one testIntellectually unacceptableInconsistent with differencesChange possible when know truthNo point beforehandThe main issue with both the current research findings and any future programmes are how they affect the European standards. The first consideration is that administratively the current situation is acceptable – we have only one test for each situation. However, the current tests make the current situation is intellectually unacceptable, which showed that there are inconsistent differences between methods assumed to give compatible results. However, there is no rational for deleting or changing the tests until we have identified which test(s) are the “correct” ones. Therefore, the necessary changes can be made when we know truth behind the differences found. There is no point in making arbitrary changes before then.
150 Conclusions Test results conflict Current Standards do not allow conflictEN defines single methodChoice of method not rationalResearch neededCorrelate test results with site experienceIdentify relevant tests for each situationPossible revisions needed to parts of EN and EN 12697The conclusions are that:The test results obtained do conflict.The current European Standards do not allow conflict In particular, EN defines a single method for each situation.The current choice of the available methods are not necessarily rational.Research is needed to sort out the truth, either or both correlating the test results with site experience and identifying the relevant tests that reflect each situation in practice.Once that research is completed, possible revisions needed to parts of EN and EN may be needed.
151 Francisco Sinis Transport Research Centre of CEDEX Premium pavements from alternative materials for European roads. Digests on recycling techniques General presentation of the Technical guideFrancisco SinisTransport Research Centre of CEDEX
152 WP6: Techniques for recycling ObjectiveTo provide up-dated information and recommendations about techniques and applications of recyclingPartners involvedCEDEX (Spain) Francisco SinisEUROVIA (France) Samir Soliman and Ivan DrouadaineTU Brno (Czech Republic) Jan Kudrna and Michal VarausIBDIM (Poland) Dariusz Sybilski and Krzystof Mirsky
153 WP6: Techniques for recycling Description of tasksTask 6.1Production of a technical guide on techniques of recyclingTask 6.2Review of the situation in CEE countries about recycling
154 WP6: Techniques for recycling Deliverables producedDeliverable 5 (March 2004)Report on literature review on recycling of by-products in road construction in EuropeDeliverable 12 (July 2004)Recommendations for mixing plants for recycling worksDeliverable 15 (September 2004)Review of the state of art in road and other industry by-product use in road construction and rehabilitation in the central and eastern countriesDeliverable 29 (December 2005)Guide in techniques for recycling in pavement structures
155 The guide on techniques for recycling in pavement structures
156 PARTNERS INVOLVED authors : Cedex (Spain) with the collaboration of Eurovia (France) AND TUBrno (Czech Republic)contribution to Chapter 5 (Technical Standards, Specifications or Guidelines by Country”):DRI (Denmark) - IBIDM (Poland)RUB (Germany) - EPFL (Switzerland)BAST (Germany) - TRL (United Kingdom)ECN (The Netherlands) - ZAG (Slovenia)
157 Work done for the elaboration of the guide Starting pointDeliverable D5: ”Literature review of recycling of by-products in road construction in Europe”literature analysisfirst drafts of digests of technical information by by-productformat for a technical guideDeliverable D12: “Recommendations for mixing plants for recycling works”
158 Work done for the elaboration of the guide Internal information taken into accountDeliverable D4: ”Existing specific national regulations applied to material recycling”Deliverable D7: “State of the art for test methods to detect hazardous components in road materials for recycling”Deliverable D16: “Methodology for assessing alternative materials for road construction”Deliverable D24: “Environmental annexes to road product standards”
159 Structure of the guide eleven digests of technical information one by materialfor every material the information has been mostly structured in the following chaptersOriginRecyclingUses in road constructionEnvironmental issuesTechnical standards, specifications or guidelines by countryTechnical references
166 Alternative materials considered materials from asphalt pavement recyclinghave not been included in the guide because its recycling techniques have been deeply covered by PIARC working groupsmaterials from concrete pavement recyclinghave been incorporated under the “building demolished by-products” digest
167 Structure of the guide Recycling properties of the waste material or by-productphysicalchemicalrecycling processdescriptionquality control of the processproperties of the recycled material
168 Structure of the guide Uses in road construction Uses Special considerations on design and constructionQuality control of the construction processExamples or references of uses
169 Summary of used by-products in road construction
171 Colliery spoil / mining waste rocks Origin It is referred for this digest to:By-products originated in the exploitation of coal and anthracite shafts and mines, as well as those resulting from the coal wash activities.mine spoils:Waste material from exploitation of shafts and mines (basically fitting rocks from coal layers: carbonaceous shale and sandstones) (10%)washery spoils:Waste material obtained after coal wash (90%)dump spoilsthe result of stocking MS and WSunburnt: Resulting from theburnt: The result of the auto-combustion of the coal included in the unburnt spoils. Reddish colour and higher strengthThe term mining waste rocks, as well as other ones commonly used such as colliery spoil, minestone spoil or coal refuse, may apply to different materials. As far as the technical description to be used for this digest, it refers to those by-products originated in the exploitation of coal and anthracite shafts and mines, as well as those resulting from the coal wash activities, usually stocked in tips.The waste materials from the exploitation of coal and anthracite shafts and mines are usually referred to as mine spoils and are basically composed of fitting rocks from coal layers. These rocks are usually slates, carbonaceous shale and sandstones and represent about 10% of the total production of mining waste rocks.The waste materials obtained after coal wash are usually referred to as washery spoils and represent close to 90% of the total production of mining waste rocks.Dump spoils are the result of stocking both mine and washery spoils. Dump spoils usually present a varying grading according to the initial nature of the constitutive spoils and their level of degradation and disintegration.Dump spoils can also be subdivided into unburnt and burnt spoils. Unburnt spoils are the waste materials resulting from the coal stocked in a dump. Burnt spoils are the result of the auto-combustion of the coal included in the unburnt spoil mass; they usually present a reddish colour, have no coal at all, have a higher strength than the non-calcinated ones and can be found sort of welded to one another.
172 Colliery spoil / mining waste rocks Recycling. Waste material Mine spoils, the waste material from the exploitation of mine galleries and rock works spoils, presents an irregular grading. This material is not degraded and barely presents coal.Washery spoils have a very regular grading and composition, being usually neither degraded nor disintegrated when coming out of the mine washery. Coal content is variable and depends upon the particular grading of the material used in the mine washery. It presents a grey colour with a certain amount of slabs.Both types of dump spoil (burnt and unburnt spoil) present a very variable grading depending on their constitutive spoils. It is common to find particles over 50 mm. It is not rare to find diameters from decimetre to metre dimensions in the case of unburnt dump spoilsBurnt dump spoils are granular materials with a continuous grading with a certain contribution of slab and fragile compounds. Maximum size of this type of dump spoils reaches 300 mm usually, while the content of fine particles is below 10% under normal situations and presents no plasticity.This Table, “Physical characteristics of a sample of colliery spoil (<50 mm)”, presents a summary of the properties of a sample according to a research conducted in Spain (ESTERAS, S. et al., 1994).PHYSICAL CHARACTERISTICS OF A SAMPLE OF COLLIERY SPOIL (<50mm)(ESTERAS, S.et al..1994)
173 Colliery spoil / mining waste rocks Recycling. Waste material From a chemical perspective, according to some research in Spain (González-Cañibano, J., 1991), colliery spoil usually presents a high amount of SiO2 close to 40-70% and an important part of Al2O3, with certain smaller amounts of Fe2O3, K2O and Na2O. Sulphur content is variable, staying usually under 1%. Furthermore, colliery spoil contains fixed carbon up to 16% (coal colliery spoil) and 27% (anthracite colliery spoil) without taking into consideration ash and volatile materials.In the case of mining areas such as the north of Spain, the average carbon content in unburnt spoils is about 5%; this percentage may increase up to 30% in the case of the oldest dumps.Mining spoils present a pH values close to 7, in some cases slightly alkali, but they may produce acid lixiviates in contact with water and pyrites. However, these lixiviates can be rapidly neutralized by the action of the alkali elements in the mining spoil itself. Sulphur content in coal spoils produced in countries such as Spain varies from 0,03% to 3,68%.This Table, “Chemical composition of colliery spoils in the UK”, shows the percentages of the main chemical compounds found in both burnt and unburnt spoils in the UK (SHERWOOD, P., 2001).CHEMICAL COMPOSITION OF COLLIERY SPOILS IN THE UK(SHERWOOD,P..2001)
174 Colliery spoil / mining waste rocks Recycling process no direct use in road constructionabundance of very thick sizesrecycling process depends of the final usegeneralExclude bigger sizes by sievingwashery spoils for embankmentsall-in-aggregates from dumping as aggregatesCrushing and grading to fulfil specificationsunburnt spoils in subgradesElimination of particles inferior to 20 mmThe abundance of very thick sizes of all-in-aggregates from dumping disqualifies the direct use of colliery spoil as aggregates in road construction. A previous crushing and material ranging is necessary to fulfil all the required grading specifications.On the other hand, when dealing with washery spoils, no previous treatment is required to use these waste materials as layers in dumping or embankments; however, it is advisable to sieve the material to exclude the bigger sizes.The use of unburnt spoils in subgrade layers may also need the elimination of particles inferior to 20 mm to reduce water problems once the material has been extended, mainly due to the fact that the extension process usually causes a certain degree of degradation for the material, in particular from 10 to 19 mm. No volume increase of material inferior to 80 μm, due to degradation during compaction and extension, has been detected.
175 Colliery spoil / mining waste rocks Recycling. Recycled material The all-in aggregate made of burnt spoils for road construction is usually separated according to 20 or 25 mm; the retained portion is milled and classified. The density of the particles of the processed material is about 2,7 t/m3. The Table “Properties of the recycled burnt and unburnt spoil” shows the characteristics of burnt and unburnt colliery spoils treated in Spain for their use in road construction (ESTERAS, S. et al., 1994). The properties shown in this table were obtained after milling of run-of-mine burnt spoils to size inferor to 50 mm with the purpose of improving their index of shape. In the case of the unburnt spoils, the fraction inferior to 25 mm was not used due to the particular plasticity and low bearing strength. The bigger material was crushed down to 50 mm according to specifications for granular materials.PROPERTIES OF RECYCLED BURNT AND UNBURNT SPOILS(ESTERAS,S. et al..1994)
176 Colliery spoil / mining waste rocks Uses in road construction Colliery spoils have been commonly used in several European countries in road construction. The main uses have been the following:• Embankments, capping layers and selected fills.• Granular materials.• Cement-stabilised materials.Table “Uses of colliery spoil in the UK” shows the legally allowed uses of mining spoils in the UK in road construction (SHERDWOOD, P.,2001).USES OF COLLIERY SPOIL IN THE UK(SHERDWOOD, P..2001)
177 Colliery spoil / mining waste rocks Uses in road construction Embankments, capping layers and fillsSpainUnburnt spoils can be used in embankmentsCare in grading curve: avoid big sizes and reduce fine portionBurnt spoils can be used in sub-bases constructionUnited KingdomA great variety of performancesUnburnt spoils are permitted for embankments and as fill materialBurnt spoils are permitted as fill material and capping material provided it meets the requirements of SHW . They are vulnerable to freezing temperatureFranceBurnt spoils have been mainly used in subgradesEmbankments, capping layers and selected fillsFrom the Spanish experience, unburnt spoils can be used in embankments paying attention to some corrections that need to be taken care on in the grading curve in order to avoid the use of big sizes and reduce the presence of the finest portion. Burnt spoils can be used in sub-bases construction and, obviously, in embankments and filling. However, their use in these two last applications may be a waste of potential due to the high quality of these type of spoils.In the UK about 8 million tonnes per year were used in motorway construction in the 1970s. A great variability of the performance of the dump spoils used as bulk fill has been detected. The main reason is the fact that fillings contain burnt spoils, partially burnt spoils, unburnt spoils and mine tailing. These last ones may cause some trouble when used as fillings. The presence of sulphates should not be a problem unless concrete structures may be located in the area of influence.Well-burnt spoil is permitted for use as fill material provided it meets the requirements of the Specification for Highway Works. The Specification for Highway Works includes the technical specifications for the use of colliery spoil as a granular capping material. Unburnt spoils are excluded but, on the other hand, burnt spoils are allowed for this use as long as they fulfil the required specifications Most of the unburnt spoils are not susceptible to be damaged by freezing. On the other hand, burnt spoils are very vulnerable to freezing temperatures.In France burnt spoils are not available normally because they are frequently used in subgrades. Nowadays, unburnt spoils from dumpings are been used for this purpose; they are mainly made of washery spoils.
178 Colliery spoil / mining waste rocks Uses in road construction Granular bases and subbasesin the UKSHW (1998): Difficult for burnt spoils to fulfil the requirements for unbound sub-bases (durability)in SpainUnburnt spoils: sub-bases for light traffic situationsBurnt spoils may be used as granular sub-base for all level of traffichydraulic bound sub-basesSHW permitted the use of both as aggregate in CB SB MGranular bases and sub-basesRelated to the use of colliery spoil as sub-base layers in the UK, the recent editions of the SHW (Highways Agency et al, 1998) have made it difficult for burnt colliery spoil to fulfil the requirements for unbound sub-bases materials because there is a durability requirement in terms of the magnesium soundness value. The 1998 edition stipulates the sulphate soundness value of 75% (equivalent to 25% when tested to EN (CEN, 1998), which records the “unsound“ rather than the “sound“ proportion). (SAMARIS D7, 2004)In Spain unburnt spoil may be used as sub-bases for light traffic situations as long as the sizes under mm are eliminated by sieving and the remaining fraction is crushed. It could also be used in granular sub-bases construction if the treated material fulfils all the specifications (CBR and fines plasticity in particular). Burnt spoils may be used as granular sub-bases for all level of traffic. If the recycling process allows improving the shape and reducing Los Angeles coefficient under 35, this material may be used as granular bases for medium and light traffic.Hydraulic bound sub-basesRelated to the use of colliery spoil as cement bound sub-base material, in the UK, the Specification for Higway Works (SHW) permits the use of both unburnt and burnt colliery spoils as aggregate in cement bound sub-base material.
179 Colliery spoil / mining waste rocks Environmental issues advantagesdecrease of stoked volumes and releases occupied landsaving of natural aggregatesdisadvantagesattention to the potential of spontaneous firewashery spoils may contain sulphates It should be required:special cementsdetailed analysis of potential lixiviate productionin the proximities of concrete structures a control of the concentration of sulphates in leaching must take placeAdvantagesThe use of materials that are stocked in dumps allows the partial or total decrease of stocked volumes in dumps and releases occupied land for whatever purpose land use planners may decide. The use of colliery spoils in road pavements represents a saving of natural aggregates and their specific use in those activities where stricter specifications are required.Disadvantages• Special attention must be paid to the potential of spontaneous fire due to the presence of coal in the spoils and the exothermic reaction of pyrites oxidation. Bearing in mind the usual coal contents (<5%), being the dumps correctly compacted and therefore a reduced amount of air available, this possibility can be technically excluded.• Washery spoils may contain sulphates. Special cements would be required in this case, as well as a detailed analysis of potential lixiviate production.• Several research projects dealing with the lixiviation process of colliery spoils have been conducted in Spain. In particular, burnt and unburnt spoils have been tested and conclusions reveal that there is no risk of pollutants dissolution with the exception of considerably small quantities of Mn and Mg and even a smaller concentration of Hg. Lixiviates correspond with SO The concentration of this element is close related to the sulphate contents in the respective colliery spoils, always produced in the process of pyrite oxidation. Generally speaking, burnt spoils present higher contents of sulphates than the unburnt ones; collected values are, in both cases, clearly under the maximum thresholds allowed in the technical prescriptions. However, a control of the concentration of these materials must take place in the proximities of concrete structures.
180 Colliery spoil / mining waste rocks Technical standards, specifications or guidelines by country European UnionCzech RepublicFranceGermanyPolandSpainUnited kingdomEuropean Union·EN 13242: “Aggregates for unbound and hydraulically bound materials for use in civil engineering work and road construction”·EN Tests for chemical properties of aggregates - Part 3: Preparation of eluates by leaching of aggregatesCzech RepublicFranceGermany·TL WB-StB 95. Technical Terms of Delivery for Colliery Spoils as Construction Material in Road und Earthwork Construction.·RuA-StB 01. Guidelines for the environmentally compatible use of industrial by-products and RC building materials in road construction. 2000· Bulletin for the use of mineral construction materials from mining in road construction and for earthworks. 2002PolandSpainUnited Kingdom·SHW Clause 601. Classification, Definitions and Uses of Earthworks Materials. Specification for Highway Works (Highways Agency). 2005·AggRegain Specifier. WRAP·ISBN Controlling the Environmental Effects of Recycled and Secondary Aggregates Production: Good Practice Guidance.ODPM. 2000
181 Colliery spoil / mining waste rocks Technical standards, specifications or guidelines by country GermanyTL WB-StB 95. Technical Terms of Delivery for Colliery Spoils as Construction Material in Road and Earthwork ConstructionRuA-StB 01. Guidelines for the environmentally compatible use of industrial by-products and RC building materials in road constructionBulletin for use of mineral construction materials from mining in road construction and for earthworks
182 Colliery spoil / mining waste rocks Technical standards, specifications or guidelines by country United KingdomSHW Clause 601. Classification, Definitions and Uses of Earthworks Materials. Specification for Highway Works (Highways Agency)AggRegain Spicifier. WRAP.2005ISBN Controlling the Environmental Effects of Recycled and Secondary Aggregates Production: Good Practice Guidance. ODPMISBN
184 Techniques for recycling S. Soliman, I. DrouadaineEUROVIA MANAGEMENT (FRANCE)
185 SAMARIS FINAL SEMINAR EUROVIA is a VINCI subsidiary: A world leader in roadworksFrench Leader in road natural aggregateEuropean leader in recycling materials5.3 billion euros net salesA network operating in 17 countries4 business lines:RoadworksIndustries and materialsQuality of life and environmentServicesJust a few word to introduce EUROVIA, EUROVIA is a subsidiary of VINCI and a world leader in road works, and important producer of natural and recycling road aggregates.With a Turnover of 5.3 billion euros and 35,000 employees operating in 17 countries our main 4 lines of activity are:Road works contractingIndustries and materialsQuality of life and environmentServices
186 SAMARIS final seminar Lines of Business Industries & Services Materials25%19%Quality of life & EnvironmentServices48%Roadworks8%Lines of BusinessIndustries and materials represent about 19% of our line of business and if we add the 25 % share of quality of life and environment it makes 44% compared to the 48% of the contracting business.
187 Industries & Materials Quarries(47Mt), binder plants(0.43Mt), asphalt plants(23Mt)Recycling and re-use platforms (105 facilities-4.5Mt)Waste from public works & civil engineering (e.g. concrete, mixes) (~ 1.3 Mt).Municipal waste incineration bottom ash (0.7 Mt).Blast furnace slag, black coal shale (1.8 Mt).Fly ash & other industrial by-products (0.5 Mt).Some figures related to the Industries and Materials activity :Total aggregate production 47 MtTotal hot mix production 23 MtRecycling platforms 105 facilities for an annual production of 4.5 Mt. The following main by-products are concerned:Building, civil engineering and roadway demolition materialsMunicipal Waste Incineration Bottom ashBlast furnace slagFly ash
188 WP6 : Techniques for recycling WP6-1 : Elaboration of a technical guide on recycling techniquesCEDEX (Spain) - Leader Francisco SinisEUROVIA (France) Samir SolimanIvan DrouadaineTURBrno (Czech Republic) Jan KudrnaMichal VarausIBDIM (Poland) Dariusz SybilskiKrzystof MirskiEurovia has been involved in the Pavement Stream of SAMARIS Project at the level of Work Package 6 «Techniques for Recycling». The objective of this Work Package is to provide up-dated information and recommendations about the techniques and applications of recycling.Eurovia is an active participant in the first task WP6-1 for the elaboration of a technical guide on recycling techniques. Our partners in this task are:Cedex SpainTUR Brno Czech Republic
189 Task 6.1: Elaboration of a technical guide on recycling techniques SAMARIS final seminarTask 6.1: Elaboration of a technical guide on recycling techniquesThe task was to provide:Report on literature review on recycling of by-products in road construction in Europe (D5)recommendations for the plants (D12)technical guide on techniques of recycling (D29)The Task of the WP6-1 was divided into three parts:The first part developed by Cedex with the contribution of the other partners represents a literature review on the recycling of waste materials or by-products in European and representative countries and formally referred to Deliverable D5. This report is considered as the starting reference for the technical guide on recycling techniques.The second one is a recommendation report for mixing plants for recycling works formally referred to Deliverable D12 by EuroviaThe third one is the technical guide on recycling techniques developed by all the partners. This guide gives guidance, for each type of material (11), on the relevant parameters to be considered, the environmental implications and the handling hazards. It include also specific operations needed for an adequate reuse of some materials.The guide is formally referred to Deliverable 29.
190 SAMARIS final seminar Three by-products: Building, civil engineering and roadway demolition materialsMunicipal Solid Waste Incineration Bottom AshCrystallized blast furnace slagEUROVIA has more than 20 years experience in recycling and the valorisation of the following industrial by-products:Building civil engineering and roadway demolition materialsMunicipal solid waste incineration bottom ashCrystallized blast furnace slag
191 Building, civil engineering and roadway demolition materials SAMARIS final seminarBuilding, civil engineering and roadway demolition materialsAll countries are concerned as producer/user< 5% of total aggregates consumptionHeterogeneous situation in EUAccuracy of data collected ?TonnageWide range of usesConsidered as inertSince several years, it has been demonstrated that recycled materials offer a very real technical and economic alternative for many projects, even some applications for motorways.The diversity of the produced materials, resulting from the diversity of “raw materials” and the various treatments techniques provide a response to a very wide range of applications, from simple backfills to stabilized base and foundation course supporting heavy traffic and even concrete.Only a few European countries (7 countries) have some experience with road and building demolition crushed materials.Few or no restrictions have been found on those materials that possess physical and chemical properties similar to the conventional virgin materials used in road construction.
192 SAMARIS final seminar Mobile recycling installation Hopper and crusher Screening0-2030-80OberbandProcessing plants can provide a wide range of technical facilities, from a simple percussion crusher, with one level of crushing, iron separation and screening as shown on the slide for a mobile plant, producing gravel and coarse aggregates.
193 SAMARIS final seminar Example of fixed recycling installation Control stationIron0/20HopperCrusheroverbandHand sorting20/60ScreenHand sortingHopper6/14CrusherIndustrial or fixed plants can have two or even three levels of crushing screening and treatment, producing aggregates, and fine sand.Raw materials are selected and stored. Storage may be selective if the facilities handle several products. The preparation prior to feeding the processing plants involves reducing the largest components with a hydraulic rock breaker, cutting long components with shears and extracting the largest impurities.The primary crusher breaks the reinforcing steel from the concrete and reduces the concrete rubble to a maximum size of 75 mm to 100 mm. As the material is conveyed to the secondary crusher, steel is removed by an electromagnetic separator, preceded by manual sorting to extract residual impurities. Secondary crushing further breaks down the RCM, which is then screened to the desired gradation. This operation can be repeated when a third level of crusher exists. To avoid inadvertent segregation of particles, coarse and fine RCM aggregates are typically stockpiled separately.Ironoverband0/6Screen
194 SAMARIS final seminar Fixed recycling installation Recycling aggregate from concreteIn general fixed plants are more sophisticated installations and may also be equipped with treatment facility such as washing and water treatment units, densimetric tables, etc. Enabling the production of great variety of materials.Most processing plants have a primary and secondary crusher (fixed plant).
195 SAMARIS final seminar Demolition materials USES Other specificities Origin SortingBuilding demolitionPlaster, timber, light mat…Road demolitionSoil, clay…USESUnbound, treated with hydraulic or bitumen binderPre-normatives European specifications are completedOther specificitiesHigh pHHigher compaction energy neededPrevent contact with sulphate sourcesTo be used as aggregates, RCM (Reclaim Concrete Materials) must be processed to remove as much as possible foreign debris, timber, paper, plastic and reinforcing steel. Steel removal can be achieved either before loading and hauling to the processing plant or in the stockyard at the plant.Reclaimed concrete material can be used as aggregate in granular bases and foundation, as aggregates in stabilized bases and foundation courses with hydraulic or bitumen binder, as aggregate for lean concrete, or for use in subgrades, embankments or engineered fills.Attention must be given to:High alkalinity of recycled aggregates in touch with water (pH>11) could cause corrosion in the aluminium or galvanized steel pipes that may enter in touch with them.Compaction equipment (type and number),Avoid contact with soil containing sulphates.
196 Municipal Solid Waste Incineration Bottom Ash SAMARIS final seminarMunicipal Solid Waste Incineration Bottom AshMost countries are concerned as producers3 countries are involvedExperimental stage in othersVery low quantity / aggregate marketHigh quantity / waste disposalElaboration process neededEnvironmental specificityMost countries are concerned as producers of raw Bottom ash.Bottom ash is the most important residue of the incineration in weight (25-30 %), in modern incineration gas treatment produce also solids concentrating most of the pollution contained in municipal waste or created during combustion.MSWI BA are produced in urban areas where construction works need materials.The raw bottom ash is usually not suitable for a direct use, it has to be elaborated to reach geotechnical properties and environmental stabilisation.The total production is very low compared to aggregate market but higher compared to non dangerous waste disposal.
197 SAMARIS FINAL SEMINAR Example of elaboration process - Specific unit - Waterproof area- Covered stocks0/308/30ElaboratedBottom ashNon ferrous metalNFSNFSScreenCrible0/88/1212/30Secondary ironOBCrusher0/30>200 mmIn this example of an elaboration plant the first operations are the gradation to 0/30 mm and a primary iron separation, a wind tunnel removes macroscopic residual unburned particles.In the second part of the plant there is a secondary fine iron separator and two non ferrous metal separators (Eddy current machine).The non ferrous separation is performed on up to 6 or 8 mm sized particles.The final typical elaborated bottom ash is a 0/30 mm well graduated gravel.Hand sortingOB30/200TrommelHopperWind tunnelPrimary IronUnburnedMSWI BA
198 SAMARIS final seminar Bottom ash elaboration installation Recycling aggregate from MSWI BAIllustration of the previous synoptic.Picture of > 8 mm particles of elaborated bottom ash.
199 SAMARIS final seminar Municipal Solid Waste Incineration Bottom Ash: Origin separate from incineration gas treatment residuesSorting: metals (Fe, non ferrous), unburnedWeathering: carbonatation of lime, pH decrease, monitoringMoisture content managementUses:Mainly backfillRoad foundation layerTreatment with hydraulic or foam bitumenRestricted areaThe specificity of MSWI BA valorisation chain is :In the origin a proper production with a complete separation from the incineration gas treatment residues,Sorting of ferrous and non ferrous metal,Unburned residual particles removing.These stages should be practiced with recent technology utilities to reach the best recovery rate.The environmental stabilisation is reached by the natural aging of the MSWI BA in about 3 months. The storage condition during the weathering are fixed to maximise the contact with air and reach at the end an optimal moisture content in regard to further use.The elaborated bottom ash is mainly used in backfill and increasingly in road foundation layer where these are used as aggregate. Treatment with hydraulic or foam bitumen is possible to increase mechanical performance.The contact with natural water is limited :No use in porous structure,No use in tap water production area or flooding zone.
200 SAMARIS final seminar Aggregates standard and bottom ash Pre-normative European specifications are being discussed for future implementation in aggregates standard :Al contentLoss of ignitionSoundnessEnvironmental issuesNational documents are appliedControl on product use batch leaching testDefined protection areaCEN dangerous substances mandate should provide harmonized specificationsElaborated bottom ash is in the CEN aggregate mandate as artificial aggregates.The actual standardization work is to define the additional harmonized requirement for this industrial by-product.The requirements are elaborated to assure a geotechnical safety of use of the aggregate produced from bottom ash used in base and foundation layer, it could concern :Al content,Loss of ignition,Soundness (minimum weathering period).Concerning environment the national regulations are currently applied, they fix the environmental quality in regards to the result of a leaching test, in association with the definition of restricted use areas.
201 Foam bitumen or emulsion + water ramp SAMARIS final seminarCold mixing plant for lime, hydraulic binder, emulsion and foam bitumen treatments10/144/100/4Cementor limesiloAdhesiveAgentFoam bitumen or emulsion + water rampStoragePlug millSlag or fly ashThe recycled aggregates from the three by-products can be treated in a cold mixing plant as shown.The treatments can be with a hydraulic binder or foam bitumen. In the case of foam treatment, aggregates are cold and the bitumen is pulverized with the foam process at 165°C. Temperature of the final product is ambient temperature.These treatment enlarge the use possibilities and in some cases improve the environmental stabilization.Cold treatments (in plant or on site) are increasing to reduce energy consummation in heating aggregates.This orientation needs a development of new mixing plant, binder and additives.
202 SAMARIS final seminar Increase mechanical performances Foam and emulsion treatment are promising
203 SAMARIS final seminar Crystallized blast furnace slag High performance aggregateComplete range of use in road constructionVolume stabilityInert material in many casesA few words concerning a well know by-product.
204 SAMARIS final seminarElaboration close to natural aggregate with separation of residual ironHigh wear of crushing, sieving equipmentHigh density and porosityNormative European specifications are achievedHigh performance aggregates without environmental restrictions. Aggregate normative European specifications are achieved.
205 Quality of life & Environment SAMARIS final seminarCoherent & Complementary - Lines of BusinessQuarriesRecyclingRe-useBinder PlantsMix PlantsRoad worksQuality of life & EnvironmentThe mineral industrial by-products are sustainable sources of aggregate in two conditions:environmental compatibility in the final use andgeotechnical properties and long term stability.Industrially speaking the production of aggregate from by-products needs specific facilities and experience.These activities integrate naturally in an organization of quarries and construction by developing an environmental competence.Services