1. High-Performance Concrete

2. Characteristics of High- Performance Concretes n High strength n High early strength n High modulus of elasticity n High abrasion resistance n High durability and long life in severe environments n Low permeability and diffusion n Resistance to chemical attack

3. High-Performance Concrete Characteristics of High- Performance Concretes n High resistance to frost and deicer scaling damage n Toughness and impact resistance n Volume stability n Ease of placement n Compaction without segregation n Inhibition of bacterial and mold growth

4. High-Performance Concrete Materials Used in High- Performance Concrete (1) MaterialPrimary Contribution/Desired Property Portland cementCementing material / Durability Blended cement Cementing material / Durability / High strength Fly ash / Slag / Silica fume Calcined clay/ Metakaolin Calcined shale SuperplasticizersFlowability High-range water reducersReduce water-cement ratio Hydration control admix.Control setting

5. High-Performance Concrete Materials Used in High- Performance Concrete (2) MaterialPrimary contribution/Desired property RetardersControl setting AcceleratorsAccelerate setting Corrosion inhibitorsControl steel corrosion Water reducersReduce cement and water content Shrinkage reducersReduce shrinkage ASR inhibitorsControl alkali-silica activity Polymer/latex modifiersDurability Optimally graded aggr.Improve workability/reduce paste

6. High-Performance Concrete Selected Properties of High- Performance Concrete (1) PropertyTest MethodCriteria that may be specified High StrengthASTM C 3940-140 MPa @ 28 to 91 days H-E Comp. StrengthASTM C 3920-30 MPa @ 3-12 hrs.or 1-3 days H-E Flex. StrengthASTM C 782-4 MPa @ 3-12 hrs.or 1-3 days Abrasion ResistanceASTM C 9440-1 mm depth of wear Low PermeabilityASTM C 1202500 to 2000 coulombs Chloride PenetrationAASHTO T 259/260 Less than 0.07% Cl at 6 months High ResistivityASTM G 59 — Low AbsorptionASTM C 6422% to 5%

7. High-Performance Concrete Selected Properties of High- Performance Concrete (2) PropertyTest MethodCriteria that may be spec. Low diffusion coeff.Wood, Wilson, Leek1000 x 10 -13 m/s Resistance to chemical attack sat. solution in wet/dry environment No deterioration after 1 yr. Sulphate attackASTM C 10120.1% max. exp. @ 6 mos. High Mod.of Elast. (E)ASTM C 469More than 40 GPa High resistance to F/T damage ASTM C 666 Procedure A Durability Factor 95-100 @ 300 -1000 cycles High resistance to deicer scaling ASTM C 672 Rating 0-1 or mass loss 0 to 0.5 kg/m 3 after 50-300 cycles Low shrinkageASTM C 157Less than 400 millionths Low creepASTM C 512Less than normal concrete

8. High-Performance Concrete High-Early-Strength Concrete n High-early compressive strength ASTM C 39 (AASHTO T 22) 20 to 28 MPa (3000 to 4000 psi) at 3 to 12 hours or 1 to 3 days n High-early flexural strength ASTM C 78 (AASHTO T 97) 2 to 4 MPa (300 to 600 psi) at 3 to 12 hours or 1 to 3 days

9. High-Performance Concrete High-Early-Strength Concrete n Type III or HE high-early-strength cement n High cement content 400 to 600 kg/m 3 (675 to 1000 lb/yd 3 ) n Low water-cementing materials ratio (0.20 to 0.45 by mass) n Higher freshly mixed concrete temperature n Higher curing temperature May be achieved by —

10. High-Performance Concrete High-Early-Strength Concrete n Chemical admixtures n Silica fume (or other supplementary cementing materials) n Steam or autoclave curing n Insulation to retain heat of hydration n Special rapid hardening cements May be achieved by —

11. High-Performance Concrete Strength Data for Fast-Track Bonded Overlay Age Compressive strength, MPa (psi) Flexural strength, MPa (psi) Bond strength, MPa (psi) 4 hours1.7 (252)0.9 (126)0.9 (120) 6 hours7.0 (1020)2.0 (287)1.1 (160) 8 hours13.0 (1883)2.7 (393)1.4 (200) 12 hours17.6 (2546)3.4 (494)1.6 (225) 24 hours23.9 (3467)4.2 (604)2.1 (302) 7 days34.2 (4960)5.0 (722)2.1 (309) 28 days40.7 (5900)5.7 (830)2.5 (359)

12. High-Performance Concrete Strength Development of HE Strength Concrete Cement = 390 kg/m 3 (697 lb/yd 3 ) w/c = 0.46

13. High-Performance Concrete Strength Development of HE Strength Concrete Cement = 504 to 528 kg/m 3 (850 to 890 lb/yd 3 ) w/c = 0.46

14. High-Performance Concrete Effect of Blanket Insulation

15. High-Performance Concrete High-Strength Concrete n 90% of R/M concrete 20 MPa - 40 MPa @ 28-d (most 30 MPa – 35 MPa) n High-strength concrete by definition — 28 day – compr. strength  70 MPa (10,000 psi)

16. High-Performance Concrete High-Strength Concrete Materials n Base selection on: u mortar-cube tests u comparative concrete strengths at 28, 56, 91 days n Use cement yielding highest concrete strength at extended ages (91-days) n Cement should have min. 7-day mortar cube strength of 30 MPa (4350 psi) n Trial mixture with cement contents between 400 and 550 kg/m 3 (675 and 930 lb/yd 3 ) Cements —

17. High-Performance Concrete High-Strength Concrete Materials n 9.5 - 12.5 mm (3/8 - 1/2 in.) nominal maximum size gives optimum strength n Combining single sizes for required grading allows for closer control and reduced variability in concrete n For 70 MPa and greater, the FM of the sand should be 2.8 – 3.2. (Lower may give lower strengths and sticky mixes) Aggregates —

18. High-Performance Concrete High-Strength Concrete Materials n Fly ash, silica fume, or slag often mandatory n Dosage rate 5% to 20% or higher by mass of cementing material. n Some specs. – silica fume 10% max. Supplementary Cementing Materials —

19. High-Performance Concrete High-Strength Concrete Materials n Use of water reducers, retarders, HRWRs, or superplasticizers — mandatory in high-strength concrete n Air-entraining admixtures not necessary or desirable in protected high-strength concrete. u Air is mandatory, where durability in a freeze-thaw environment is required ie. bridges, piers, parking structures u Recent studies: H w/cm ≥ 0.30—air required H w/cm < 0.25—no air needed Admixtures —

20. High-Performance Concrete High-Strength Concrete n Central Plant or Truck Mixers n Truck mixing — reduce loads to 90% of rated capacity n Prequalification of concrete suppliers is recommended n Field trials with full loads delivered to the site or a mock-up are essential to assess the batching, mixing, transporting and placing systems to be used Mixing —

21. High-Performance Concrete High-Strength Concrete n Delays in delivery and placing must be eliminated n Consolidation very important to achieve strength n Slump generally 180 to 220 mm (7 to 9 in.) n Little if any bleeding—fog or evaporation retarders have to be applied immediately after strike off to minimize plastic shrinkage and crusting n 7 days moist curing Placing, Consolidation, and Curing

22. High-Performance Concrete Mix Proportions and Properties of High-Strength Concrete C + SF + FAC + SF Cement, Type I, kg/m 3 475564 Silica fume, kg/m 3 2489 Fly ash, kg/m 3 59— HRWR Type F, liters/m 3 11.620.11 Retarder, Type D, liters/m 3 1.051.46 Water to cementing materials ratio0.290.22 Slump, mm248254 Compressive strength, 28d, MPa92117 Compressive strength, 91d, MPa105124 Modulus of elasticity, 91d, GPa49.956.5 Drying shrinkage, 369d, millionths677527

23. High-Performance Concrete Mix Proportions and Properties of High-Strength Concrete C + SF + FAC + SF Cement, Type I, lb/yd 3 800950 Silica fume, lb/yd 3 40150 Fly ash, lb/yd 3 100— HRWR Type F, fl oz/yd 3 300520 Retarder, Type D, fl oz/yd 3 2738 Water to cementing materials ratio0.290.22 Slump, in.9.7510 Compressive strength, 28d, psi13,30017,000 Compressive strength, 91d, psi15,17018,030 Modulus of elasticity, 91d, million psi7.248.20 Drying shrinkage, 369d, millionths677527

24. High-Performance Concrete n Cement:(865 lb/yd 3 ) n w/c: 0.25 n Silica fume: (72 lb/yd 3 ) n Fine aggr.: (1155 lb/yd 3 ) n HRWR: (420 oz/yd 3 ) n 28d strength: (17,200 psi) n 91d strength: (21,000 psi) n Cement: 513 kg/m 3 n w/c: 0.25 n Silica fume: 43 kg/m 3 n Fine aggr.: 685 kg/m 3 n HRWR: 15.7 L/m 3 n 28d strength: 119 MPa n 91d strength: 145 MPa Two Union Square Seattle, 1988

25. High-Performance Concrete High-Durability Concrete 1970s and 1980s focus on — High-Strength HPC Today focus on concretes with high durability in severe environments resulting in structures with long life — High-Durability HPC

26. High-Performance Concrete High-Durability Concrete n Abrasion Resistance n Blast Resistance n Permeability n Carbonation n Freeze-Thaw Resistance n Chemical Attack n Alkali-Silica Reactivity (helps combat) n Corrosion rates of rebar (high resistivity) Durability Issues That HPC Can Address

27. High-Performance Concrete n Cement: 398 kg/m 3 (671 lb/yd 3 ) n Fly ash: 45 kg/m 3 (76 lb/yd 3 ) n Silica fume: 32 kg/m 3 (72 lb/yd 3 ) n w/c: 0.30 n Water Red.: 1.7 L/m 3 (47 oz/yd 3 ) n HRWR: 15.7 L/m 3 (83 oz/yd 3 ) n Air: 5-8% n 91d strength: 60 MPa (8700 psi) High-Durability Concrete Confederation Bridge, Northumberland Strait, Prince Edward Island/New Brunswick, 1997

28. High-Performance Concrete Self-Consolidating Concrete n developed in 1980s — Japan n Increased amount of u Fine material (i.e. fly ash or limestone filler) u HRWR/Superplasticizers n Strength and durability same as conventional concrete Self-consolidating concrete (SCC) also known as self-compacting concrete — flows and consolidates on its own

29. High-Performance Concrete Self-Consolidating Concrete

30. High-Performance Concrete Portland cement (Type I) 297 kg/m 3 (500 lb/yd 3 ) Slag cement 128 kg/m 3 (215 lb/yd 3 ) Coarse aggregate 675 kg/m 3 (1,137 lb/yd 3 ) Fine aggregate 1,026 kg/m 3 (1,729 lb/yd 3 ) Water 170 kg/m 3 (286 lb/yd 3 ) Superplasticizer ASTM C 494, Type F (Polycarboxylate-based) 1.3 L/m 3 (35 oz/yd 3 ) AE admixture as needed for 6% ± 1.5% air content SCC for Power Plant in Pennsylvania—Mix Proportions

31. High-Performance Concrete J-Ring Test for SCC

32. High-Performance Concrete Reactive-Powder Concrete (RPC) n Properties: u High strength — 200 MPa (can be produced to 810 MPa) u Very low porosity n Properties are achieved by: u Max. particles size  300  m u Optimized particle packing u Low water content u Steel fibers u Heat-treatment

33. High-Performance Concrete Mechanical Properties of RPC Property Unit80 MPaRPC Compressive strength MPa (psi)80 (11,600)200 (29,000) Flexural strength MPa (psi)7 (1000)40 (5800) Tensile strength MPa (psi)8 (1160) Modulus of Elasticity GPa (psi)40 (5.8 x 10 6 )60 (8.7 x 10 6 ) Fracture Toughness 103 J/m 2 <130 Freeze-thaw RDF90100 Carbonation mm20 Abrasion 10 -12 m 2 /s2751.2

34. High-Performance Concrete Reactive Powder Concrete