Presentation on theme: "Portland, Blended, and Other Hydraulic Cements"— Presentation transcript:
1 Portland, Blended, and Other Hydraulic Cements EB001 –Design and Control of Concrete Mixtures—14th Edition, 2002, Chapter 2, pages 21 to 56.Fig Portland cement is a fine powder that when mixed with water becomes the glue that holds aggregates together in concrete. (58420)
2 Oldest Concrete Found To Date dates around 7000 BC— a lime concrete floor found during the construction of a road at Yiftah El in Galilee, Israel.
3 Beginning of the Industry Portland cement was first patented in 1824Named after the natural limestone quarried on the Isle of Portland in the English ChannelFig Isle of Portland quarry stone (after which portland cement was named) next to a cylinder of modern concrete. (68976)
4 Portland Cement First Produced North America1871— Coplay, PennsylvaniaCanada1889 — Hull, QuebecLime and hydraulic cement first produced in Canada as early as 1830 to 1840 in Hull.Canadian natural cement producers converted existing facilities to produce superior portland cementC.B.Wrright & Sons , Hull, Quebec frst portland cement producer in Canada and almost at the same time by Napanee Cement Works, Napanee, Ontario. Two new plants for the production of portland cement followed shortly, one in Shallow Lake, near Owen Sound, Ontario, and the other at Longue Pointe, east of Montreal.
5 Fig. 2-5. Aerial view of a cement plant. (70000)
6 Primary Components of Raw Materials Necessary for Portland Cement Manufacture CalciumSilicaAluminaIronMaterials used in the manufacture of portland cement must contain appropriate proportions of calcium, silica, alumina, and iron components
7 Calcium Iron Silica Alumina Sulfate Alkali waste Aragonite Calcite Cement-kiln dustCement rockChalkClayFuller’s earthLimestoneMarbleMarlSeashellsShaleSlagBlast-furnace flue dustIron oreMill scaleOre washingsPyrite cindersCalcium silicateFly ashLoessQuartziteRice-hull ashSandSandstoneTraprockAluminum-ore refuseBauxiteCopper slagGranodioriteStauroliteAnhydriteCalcium sulfateGypsumTable 2-1. Sources of Raw Materials Used in Manufacture of Portland CementSulfate, often in the form of gypsum, is added during the grinding of the clinker to regulate the setting time of the cement and to improve shrinkage and strength development properties.
8 QuarryFig Limestone, a primary raw material providing calcium in making cement, is quarried near the cement plant. (59894)Fig Quarry rock is trucked to the primary crusher. (59893)
9 Traditional Manufacture of Portland Cement Fig Steps in the traditional manufacture of portland cement1. Stone is first reduced to 125 mm (5 in.) size, then to 20 mm (3/4 in.), and stored.
10 Raw materials are ground to powder and blended. or2. Raw materials are ground, mixed with water to form slurry, and blended.Fig Steps in the traditional manufacture of portland cement
11 3. Burning changes raw mix chemically into cement clinker. Fig Steps in the traditional manufacture of portland cement
12 4. Clinker with gypsum is ground into portland cement and shipped. Fig Steps in the traditional manufacture of portland cement
16 Dry Process Manufacture of Portland Cement Fig Steps in the modern dry-process manufacture of portland cement.1. Stone is first reduced to 125 mm (5 in.) size, then to 20 mm (3/4 in.), and stored.
17 Raw materials are ground, to powder and blended. Fig Steps in the modern dry-process manufacture of portland cement.
18 3. Burning changes raw mix chemically into clinker 3. Burning changes raw mix chemically into clinker. Note four stage preheater, flash furnaces, and shorter kiln.Fig Steps in the modern dry-process manufacture of portland cement.
19 4. Clinker with gypsum is ground into portland cement and shipped Fig Steps in the modern dry-process manufacture of portland cement.
20 Fig Rotary kiln (furnace) for manufacturing portland cement clinker. Inset view inside the kiln. (58927, 25139)
21 ClinkerGypsumFig Portland cement clinker is formed by burning calcium and siliceous raw materials in a kiln. This particular clinker is about 20 mm (3¼4 in.) in diameter. (60504)Fig Gypsum, a source of sulfate, is interground with portland clinker to form portland cement. It helps control setting, drying shrinkage properties, and strength development. (60505)
22 Process of Clinker Production Fig Process of clinker production from raw feed to the final product (Hills 2000).(1)
23 Fig. 2-10. Process of clinker production from raw feed to the final product (Hills 2000). (2)
24 Fig. 2-10. Process of clinker production from raw feed to the final product (Hills 2000). (3)
25 Portland Cement By definition — a hydraulic cement produced by pulverizing clinker consisting essentially of hydraulic calcium silicates, usually containing one or more of the forms of calcium sulfate as an interground addition.
26 Types of Portland Cement ASTM C 150 (AASHTO M 85)I NormalIA Normal, air-entrainingII Moderate sulfate resistanceIIA Moderate sulfate resistance, air-entrainingIII High early strengthIIIA High early strength, air-entrainingIV Low heat of hydrationV High sulfate resistance
27 Fig Typical uses for normal or general use cements include (left to right) highway pavements, floors, bridges, and buildings. (68815, 68813, 63303, 68809)
28 Performance of Concretes Made with Different Cements in Sulfate Soil Fig (top) Performance of concretes made with different cements in sulfate soil. Type II and Type V cements have lower C3A contents that improve sulfate resistance.
29 Performance of Concretes Made with Different W/C-Ratios in Sulfate Soil Improved sulfate resistance results from low water to cementitious materials ratios as demonstrated over time for concrete beams exposed to sulfate soils in a wetting and drying environment. Shown are average values for concretes containing a wide range of cementitious materials, including cement Types I, II, V, blended cements, pozzolans, and slags
30 Type II & Type V Sulfate Resistant Cements Fig Moderate sulfate resistant cements and high sulfate resistant cements improve the sulfate resistance of concrete elements, such as (left to right) slabs on ground, pipe, and concrete posts exposed to high-sulfate soils. (68985, 52114, 68986)
31 Outdoor Sulfate Test Type V Cement Type V Cement W/C-ratio = 0.65 Fig Specimens used in the outdoor sulfate test plot in Sacramento, California, are 150 x 150 x 760-mm (6 x 6 x 30-in.) beams. A comparison of ratings is illustrated: (top) a rating of 5 for 12-year old concretes made with Type V cement and a water-to-cement ratio of 0.65; and (bottom) a rating of 2 for 16-year old concretes made with Type V cement and a water-to-cement ratio of 0.39 (Stark 2002). (68840, 68841)
32 Moderate and Low Heat Cements Fig Moderate heat and low heat cements minimize heat generation in massive elements or structures such as (left) very thick bridge supports, and (right) dams. Hoover dam, shown here, used a Type IV cement to control temperature rise. (65258, 68983)
33 Type III High Early Strength Cements Fig High early strength cements are used where early concrete strength is needed, such as in (left to right) cold weather concreting, fast track paving to minimize traffic congestion, and rapid form removal for precast concrete. (65728, 59950, 68668)
34 White Portland CementFig White portland cement is used in white or light-colored architectural concrete, ranging from (left to right) terrazzo for floors shown here with white cement and green granite aggregate (68923), to decorative and structural precast and cast-in-place elements (68981), to building exteriors. The far right photograph shows a white precast concrete building housing the ASTM Headquarters in West Conshohocken, Pennsylvania. Photo courtesy of ASTM.
35 Blended Hydraulic Cement ASTM C 595 General —a hydraulic cement consisting of two or more inorganic constituents, which contribute to the strength gaining properties of cement.
36 Blended Cements Clinker Gypsum Portland cement Fly ash Slag Silica FumeCalcined ClayFig Blended cements (ASTM C 595, AASHTO M 240, and ASTM C 1157) use a combination of portland cement or clinker and gypsum blended or interground with pozzolans, slag, or fly ash. ASTM C 1157 allows the use and optimization of all these materials, simultaneously if necessary, to make a cement with optimal properties. Shown is blended cement (center) surrounded by (right and clockwise) clinker, gypsum, portland cement, fly ash, slag, silica fume, and calcined clay. (68988)
37 Blended Hydraulic Cements ASTM C 595 (AASHTO M 240)Type IS Portland blast-furnace slag cementType IP Portland-pozzolan cementType P Portland-pozzolan cementType I(PM) Pozzolan-modified portland cementType S Slag cementType I(SM) Slag-modified portland cement
38 Hydraulic Cements ASTM C 1157 First performance specification for hydraulic cementsCements meet physical performance test requirements rather than prescriptive restrictions on ingredients or cement chemistry as in other cement specifications.Provides for six types
39 Hydraulic Cement ASTM C 1157 Type GU General use Type HE High early strengthType MS Moderate sulfate resistanceType HS High sulfate resistanceType MH Moderate heat of hydrationType LH Low heat of hydration
40 Cement Applications Cement specification General purpose Moderate heat ofhydrationHigh earlystrengthLow heat ofsulfateresistanceHigh sulfateResistance toalkali-silicareactivity (ASR)ASTM C 150(AASHTO M 85)portland cementsIII (moderateheat option)IIIIVIIVLow alkalioptionASTM C 595(AASHTO M 240)blendedhydrauliccementsISIPI(PM)I(SM)S, PIS(MH)IP(MH)I(PM)(MH)I(SM)(MH)P(LH)IS(MS)IP(MS)P(MS)I(PM)(MS)I(SM)(MS)Low reactivityASTM C 1157GUMHHELHMSHSOption RTable 2-3. Applications for Commonly Used CementsCheck the local availability of specific cements as all cements are not available everywhere.The option for low reactivity with ASR susceptible aggregates can be applied to any cement type in the columns to the left.For ASTM C 1157 cements, the nomenclature of hydraulic cement, portland cement, air-entraining portland cement, modified portland cement, or blended hydraulic cement is used with the type designation.
41 Special cements Type Application White portland cements, ASTM C 150 I, II, III, VWhite or colored concrete, masonry, mortar, grout, plaster, and stuccoWhite masonry cements, ASTM C 91M, S, NWhite mortar between masonry unitsMasonry cements, ASTM C 91Mortar between masonry units, plaster, and stuccoMortar cements, ASTM C 1329Mortar between masonry unitsPlastic cements, ASTM C 1328M, SPlaster and stuccoExpansive cements, ASTM C 845E-1(K), E-1(M), E-1(S)Shrinkage compensating concreteOil-well cements, API-10A, B, C, D, E, F, G, HGrouting wellsWater-repellent cementsTile grout, paint, and stucco finish coatsRegulated-set cementsEarly strength and repairTable 2-4. Applications for Special CementsPortland cement Types I, II, and III and blended cement Types IS, IP, and I(PM) are also used in making mortar.Portland cement Types I, II, and III and blended cement Types IP, I(SM) and I(PM) are also used in making plaster.
42 Special cements Type Application Cements with functional additions, ASTM C 595 (AASHTO M 240),ASTM C 1157General concrete construction needing special characteristics such as; water-reducing, retarding, air entraining, set control, and accelerating propertiesFinely ground (ultrafine) cementGeotechnical groutingCalcium aluminate cementRepair, chemical resistance and high temperature exposuresMagnesium phosphate cementRepair and chemical resistanceGeopolymer cementGeneral construction, repair, wastestabilizationEttringite cementsWaste stabilizationSulfur cementsRapid hardening hydraulic cementVH, MR, GCGeneral paving where very rapid(about 4 hours) strength developmentis requiredTable 2-4. Applications for Special Cements
43 Masonry CementsType N — for Type O and Type N mortars and with portland cement for mortar Types S and MType S — for Type S mortarType M — for Type M mortarFig Masonry cement and mortar cement are used to make mortar to bond masonry units together. (68807)
44 Stucco using Masonry or Plastic Cements Fig Masonry cement and plastic cement are used to make plaster or stucco for commercial, institutional, and residential buildings. Shown are a church and home with stucco exteriors. Inset shows a typical stucco texture. (69389, 67878, 68805)
45 Finely-Ground Cements Grout penetration in soilFig (left) A slurry of finely ground cement and water can be injected into the ground, as shown here, to stabilize in-place materials, to provide strength for foundations, or to chemically retain contaminants in soil. (68810) Illustration (right) of grout penetration in soil.
46 Expansive Cement Concrete Fig Length-change history of shrinkage compensating concrete containing Type E-1(S) cement and Type I portland cement concrete (Pfeifer and Perenchio 1973).
47 Drinking Water Applications Fig Concrete has demonstrated decades of safe use in drinking water applications such as concrete tanks. (69082)
48 Chemical Compounds of Portland Cement Fig (left) Polished thin-section examination of portland clinker shows alite (C3S) as light, angular crystals. The darker, rounded crystals are belite (C2S). Magnification 400X. (right) Scanning electron microscope (SEM) micrograph of alite (C3S) crystals in portland clinker. Magnification 3000X. (54049, 54068)
49 Hydration ProductsFig Electron micrographs of (left) dicalcium silicate hydrate, (middle) tricalcium silicate hydrate, and (right) hydrated normal portland cement. Note the fibrous nature of the calcium silicate hydrates. Broken fragments of angular calcium hydroxide crystallites are also present (right). The aggregation of fibers and the adhesion of the hydration particles is responsible for the strength development of portland cement paste. Reference (left and middle) Brunauer 1962 and (right) Copeland and Schulz (69110, 69112, 69099)
50 Portland Cement Compound Hydration Reactions (Oxide Notation) 2 (3CaO•SiO2)Tricalcium silicate+ 11 H2OWater= 3CaO•2SiO2•8H2OCalcium silicatehydrate (C-S-H)+ 3 (CaO•H2O)Calcium hydroxide2 (2CaO•SiO2)Dicalcium silicate+ 9 H2O= 3CaO•2SiO2•8H2O+ CaO•H2O3CaO•Al2O3Tricalcium aluminate+ 3 (CaO•SO3•2H2O)Gypsum+ 26 H2O= 6CaO•Al2O3•3SO3•32H2OEttringite2 (3CaO•Al2O3)+ 6CaO•Al2O3•3SO3•32H2O+ 4 H2O= 3 (4CaO•Al2O3•SO3•12H2O)Calcium monosulfoaluminate+ 12 H2O= 4CaO•Al2O3•13H2OTetracalcium aluminate hydrate4CaO• Al2O3•Fe2O3Tetracalcium aluminoferrite+ 10 H2O+ 2 (CaO•H2O)= 6CaO•Al2O3•Fe2O3•12H2OCalcium aluminoferrite hydrateTable 2-5. Portland Cement Compound Hydration Reactions (Oxide Notation)Note: This table illustrates only primary transformations and not several minor transformations. The composition of calcium silicate hydrate(C-S-H) is not stoichiometric (Tennis and Jennings 2000).
51 SEMs of Hardened Cement Paste Fig Scanning-electron micrographs of hardened cement paste at (left) 500X, and (right) 1000X. (A7112, A7111)
52 Fig Relative volumes of the major compounds in the microstructure of hydrating portland cement pastes (left) as a function of time (adapted from Locher, Richartz, and Sprung 1976) and (right) as a function of the degree of hydration as estimated by a computer model for a water to cement ratio of 0.50 (adapted from Tennis and Jennings 2000). Values are given for an average Type I cement composition (Gebhardt 1995): C3S=55%, C2S=18%, C3A=10% and C4AF=8%. “AFt and AFm” includes ettringite (AFt) and calcium monosulfoaluminate (AFm) and other hydrated calcium aluminate compounds. See Table 2-5 for compound transformations.
53 Fig Relative volumes of the major compounds in the microstructure of hydrating portland cement pastes (left) as a function of time (adapted from Locher, Richartz, and Sprung 1976) and (right) as a function of the degree of hydration as estimated by a computer model for a water to cement ratio of 0.50 (adapted from Tennis and Jennings 2000). Values are given for an average Type I cement composition (Gebhardt 1995): C3S=55%, C2S=18%, C3A=10% and C4AF=8%. “AFt and AFm” includes ettringite (AFt) and calcium monosulfoaluminate (AFm) and other hydrated calcium aluminate compounds. See Table 2-5 for compound transformations.
54 Chemical composition, % Type ofportlandcementChemical composition, %SiO2Al2O3Fe2O3CaOMgOSO3Na2OeqI (mean)220.127.116.113.92.13.00.61II (mean)18.104.22.16822.214.171.124III (mean)126.96.36.199188.8.131.52IV (mean)22.25.062.51.90.36V (mean)184.108.40.206.30.48White (mean)220.127.116.1118.104.22.168Table 2-6. Chemical Composition Cements*
55 Potential compound composition,% Type ofportlandcementPotential compound composition,%Blaine finenessm2/kgC3SC2SC3AC4AFI (mean)5418108369II (mean)5519611377III (mean)179548IV (mean)4232415340V (mean)2213373White (mean)631482Table 2-6. Compound Composition and Fineness of Cements
56 Reactivity of Cement Compounds Fig Relative reactivity of cement compounds. The curve labeled “overall” has a composition of 55% C3S, 18% C2S, 10% C3A, and 8% C4AF, an average Type I cement composition (Tennis and Jennings 2000).
57 Nonevaporable Water Contents Hydrated cementcompoundNonevaporable(combined) water content(g water/g cement compound)C3S hydrate0.24C2S hydrate0.21C3A hydrate0.40C4AF hydrate0.37Free lime (CaO)0.33Table 2-7. Nonevaporable Water Contents for Fully Hydrated Major Compounds of Cement
58 Fig Cement paste cylinders of equal mass and equal cement content, but mixed with different water to cement ratios, after all water has evaporated from the cylinders. (1072)
59 Scanning-Electron Micrograph of Powdered Cement Fig (left) Scanning-electron micrograph of powdered cement at 1000X and (right) particle size distribution of portland cement. (69426)
60 Fineness of Cement ASTM C 204 ASTM C 115 Fig Blaine test apparatus (left) and Wagner turbidimeter (right) for determining the fineness of cement. Wagner fineness values are a little more than half of Blaine values. (40262, 43815)
61 Cement FinenessFig Quick tests, such as washing cement over this 45-micrometer sieve, help monitor cement fineness during production. Shown is a view of the sieve holder with an inset top view of a cement sample on the sieve before washing with water. (68818, 68819)
62 Particle Size Distribution Fig A laser particle analyzer uses laser diffraction to determine the particle size distribution of fine powders. Fig (right) illustrates typical results. (69390)
63 Soundness Test ASTM C 151 (AASHTO T 107 ) Fig In the soundness test, 25-mm square bars are exposed to high temperature and pressure in the autoclave to determine the volume stability of the cement paste. (23894)
64 Consistency of Cement Paste ASTM C 187(AASHTO T 129)Vicat plungerFig Normal consistency test for paste using the Vicat plunger. (68820)
65 Consistency of Mortar ASTM C 230 (AASHTO M 152) and ASTM C 1437 Flow tableFig Consistency test for mortar using the flow table. The mortar is placed in a small brass mold centered on the table (inset). For skin safety the technician wears protective gloves while handling the mortar. After the mold is removed and the table undergoes a succession of drops, the diameter of the pat is measured to determine consistency. (68821, 68822)
66 Setting Time ASTM C 191 (AASHTO M 131) Vicat apparatus Fig Time of set test for paste using the Vicat needle. (23890)
67 Setting Time ASTM C 266 (AASHTO M 154) Gillmore needle Fig Time of set as determined by the Gillmore needle. (23892)
68 Setting Times for Portland Cements Fig Time of set for portland cements (Gebhardt 1995 and PCA 1996).
69 Mortar Cubes ASTM C 109 (AASHTO T 106) Fig mm (2-in.) mortar cubes are cast (left) and crushed (right) to determine strength characteristics of cement. (69128, 69124)
70 Strength Development of Mortar Cubes Fig Relative strength development of portland cement mortar cubes as a percentage of 28-day strength. Mean values adapted from Gebhardt 1995.
71 Strength Development Type I and II Cements Fig Strength development of portland cement mortar cubes from combined statistics. The dashed line represents the mean value and the shaded area the range of values (adapted from Gebhardt 1995).
72 Strength Development Type III, IV, and V Cements Fig Strength development of portland cement mortar cubes from combined statistics. The dashed line represents the mean value and the shaded area the range of values (adapted from Gebhardt 1995).
73 Fig. 2-44. Heat of hydration can be determined by ASTM C 186 (68823)
74 Fig. 2-44. Heat of hydration can be determined by a conduction calorimeter. (68824)
75 Heat of Hydration at 7 Days Type I cementType II cementType II Moderate heat cementType III cementType IV cementType V cement% of Type I10099751066789Table 2-8. ASTM C 186 Heat of Hydration for Selected Portland Cements from the 1990s, kJ/kg
76 Heat EvolutionFig Heat evolution as a function of time for cement paste. Stage 1 is heat of wetting or initial hydrolysis (C3A and C3S hydration). Stage 2 is a dormant period related to initial set. Stage 3 is an accelerated reaction of the hydration products that determines rate of hardening and final set. Stage 4 decelerates formation of hydration products and determines the rate of early strength gain. Stage 5 is a slow, steady formation of hydration products establishing the rate of later strength gain.
77 Fig. 2-46. Loss on ignition test of cement. (43814)
78 Density of Cement Le Chatelier flask ( ASTM C 188 or AASHTO T 133) Helium pycnometerFig Density of cement can be determined by (left) using a Le Chatelier flask and kerosine or by (right) using a helium pycnometer. (68825, 68826)
79 Bulk Density Bulk density of cement varies between 830 kg/m3 (52 lb/ft3)and1650 kg/m3 (103 lb/ft3).Fig Both 500-mL beakers contain 500 grams of dry powdered cement. On the left, cement was simply poured into the beaker. On the right, cement was slightly vibrated—imitating consolidation during transport or packing while stored in a silo. The 20% difference in bulk volume demonstrates the need to measure cement by mass instead of volume for batching concrete. (68970)
81 Differential Scanning Calorimetry Thermogram of a Cement Paste after (a) 15 min and (b) 24 h of HydrationFig Differential scanning calorimetry thermogram of a portland cement paste after (a) 15 minutes and (b) 24 hours of hydration. C = calcium hydroxide; E = ettringite; G = gypsum; and S = syngenite.
82 Virtual Cement Testing Fig Two-dimensional image of portland cement. Colors are: red–tricalcium silicate, aqua–dicalcium silicate, green– tricalcium aluminate, yellow–tetracalcium aluminoferrite, pale green–gypsum, white–free lime, dark blue–potassium sulfate, and magenta–periclase. The image was obtained by combining a set of SEM backscattered electron and X-ray images (NIST 2001).
83 Transporting CementFig Portland cements are shipped from the plant silos to the user in bulk by (left to right) rail, truck, or water. (59899, 59355, 59891)
84 Packaging and StorageFig A small amount of cement is shipped in bags, primarily for mortar applications and for small projects. (59411)Fig When stored on the job, cement should be protected from moisture. (36052)