Institute for Road Construction and Maintenance - Vienna University of Technology ISTU O PTIMIZED P AVEMENT D ESIGN W ITH R ESPECT TO Q UALITY AND E CONOMY Institute for Road Construction and Maintenance Vienna University of Technology J. Litzka

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY General objective of pavement design 2 Structural efficiency during the whole design period Based on given random conditions - Design traffic load - Bearing capacity of subgrade - Material properties of pavement layers

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY For routine application (1) 3 Average or minimum values of - Subgrade - Material properties and fatigue behaviour Pavement design according to given design traffic (load class) e.g. catalogue type (like Austrian RVS 3.63, based on analytical calculations)

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY For routine application (2) 4 Resulting in a number of technically equivalent pavement solutions Based on availability of materials and/or on cost comparison the optimal solution can be selected together with possible alternatives But still a general solution based on plausible assumptions, not always most cost effective

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY 5 Design table RVS 3.63, bituminous pavements

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Possible improvement of economic efficiency (1) 6 Specific analytical design using the underlying procedure for the catalogue, but Real given values of bearing capacity of subgrade, material characteristics of layers, specific fatigue laws Also possibility to include new, innovative, not standardised materials

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Possible improvement of economic efficiency (2) 7 Example

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Essential precondition 8 Exact and reliable information about input characteristics Performance orientated laboratory tests (stiffness modulus, fatigue behaviour etc.) (t) (t) Traffic forecast of high accuracy

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Benefits of specific pavement design 9 Better adaptation to existing subgrade situation Better utilisation of material properties Possibility for innovative materials and solutions - Alternative bids - Performance related contracts

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Further advantage of specific analytical design 10 Stage by stage construction - Stage 1 as basic solution for first part of design period - Stage 2 designed based on existing layer properties and realistic design traffic Better reliability and also acting as maintenance procedure but: Do not overlook the right moment

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Consideration of costs 11 Construction costs Life-cycle costs - Construction - Maintenance - Additional user costs (e.g. time loss) - Environmental costs (possibly) Routine Rehabilitation including - Traffic management at construction sites - Methods/measures - Intervals

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Calculation of life-cycle costs 12 Prognosis of development of pavement condition necessary Prediction of life time, change of condition indicator-values and thus prediction of time and type of maintenance measure Basic tasks for PMS/e.g. VIAPMS

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Change of approach and responsibilities 13 Only construction costs considered Client chooses contractor according to cost comparison Sometimes alternatives compared Actual: Consider life-cycle costs At least for road owner costs (construction and maintenance) New approach (even if normal tender):

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY For functional contracts (PPP) 14 Responsibility of concessionaire/contractor to consider - Complete life-cycle costs - Including additional user costs (e.g. loss of toll/fee during rehabilitation works, closures) Normally compliance with trigger values of pavement condition required

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Functional contracts - example 15 1,5 1,0 2,0 2,5 3,0 3,5 4,0 4,5 5, technical parameter [mm] condition index CI [-] 0 I II III IV V condition class very good good fair poor very poor Threshold level Warning level

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Most crucial point: Performance models 16 Standard- type pavements, traditional materials - Empiric results from database analysis But still more risks compared with routine application within maintenance planning - Starting from new pavement - No calibration of performance models to actual measurements possible

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Most crucial point: Performance models (2) 17 Innovative, new materials and pavements - Prognosis based on analytical calculation With this also required minimum quality of road condition secured - First assumption based on existing empiric functions and adaptation by periodic condition measurements (normally required in any case)

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Optimized solution 18 Construction costs Maintenance costs including additional user costs Minimum life-cycle costs - Most economic solution - In compliance with given quality requirements

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Development Pavement Condition – Concrete Pavement 19 Concrete Pavement Bit. Base Course Subbase Threshold Level Warning Level Exchange of distressed slabs and thin bit. overlay

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Development Pavement Condition – Asphalt Pavement 20 Wearing Course Bit. Base Course Subbase Threshold Level Warning Level Reinforcement Base Course Overlay Total thickness according to design

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Development Pavement Condition – Asphalt Pavement 21 Wearing Course Bit. Base Course Subbase Threshold Level Warning Level Reinforcement (2 nd construction stage) Base Course Overlay 2-stage pavement construction

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Comparison Total Costs (including user costs) 22 Reinforcement (2 nd construction stage) Overlay Reinforcement Replacement of distressed slabs and thin overlay Overlay

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Conclusions (1) 23 Increased traffic loads Limited budgets Saving of resources Minimised impact to road users (important for toll roads) Optimized pavement design necessary with respect to

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Conclusions (2) 24 Improved design methods Improved materials Long life, modular pavements Improved construction quality (very important) Optimized pavement design possible by applying

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Conclusions (3) 25 Normal contract Optimized pavement design necessary and possible if - Administration responsible for design and maintenance Functional contracts (PPP) - Concessionaire responsible for design, construction and maintenance over the full concession period together with guaranteed remaining lifetime after termination of contract

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY Conclusions (4) 26 Improved, innovative materials Improved, performance related laboratory tests High quality of construction Optimal maintenance organisation For optimized pavement design necessary in any case and Enough time for development of alternative solutions and attributed laboratory tests and calculations during the bidding process

Institute for Road Construction and Maintenance - Vienna University of Technology ISTU J. LITZKA - OPTIMIZED PAVEMENT DESIGN WITH RESPECT TO QUALITY AND ECONOMY 27 Thank you for your attention