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High-Performance Concrete
Characteristics of High-Performance Concretes
■ High strength■ High early strength■ High modulus of elasticity■ High abrasion resistance■ High durability and long life in
severe environments■ Low permeability and diffusion■ Resistance to chemical attack
High-Performance Concrete
Characteristics of High-Performance Concretes
■ High resistance to frost and deicer scaling damage
■ Toughness and impact resistance
■ Volume stability■ Ease of placement■ Compaction without
segregation■ Inhibition of bacterial and
mold growth
High-Performance Concrete
Materials Used in High-Performance Concrete (1)
Control settingHydration control admix.Reduce water-cement ratioHigh-range water reducers
FlowabilitySuperplasticizersCalcined shaleCalcined clay/ MetakaolinFly ash / Slag / Silica fume Cementing material /
Durability / High strength
Blended cementCementing material / DurabilityPortland cement
Primary Contribution/Desired PropertyMaterial
High-Performance Concrete
Materials Used in High-Performance Concrete (2)
Improve workability/reduce paste Optimally graded aggr.DurabilityPolymer/latex modifiers
Control alkali-silica activityASR inhibitorsReduce shrinkageShrinkage reducers
Reduce cement and water contentWater reducersControl steel corrosionCorrosion inhibitors
Accelerate settingAcceleratorsControl settingRetarders
Primary contribution/Desired propertyMaterial
High-Performance Concrete
Selected Properties of High-Performance Concrete (1)
2% to 5%ASTM C 642Low Absorption
—ASTM G 59High Resistivity
Less than 0.07% Cl at 6 monthsAASHTO T 259/260
Chloride Penetration
500 to 2000 coulombsASTM C 1202Low Permeability
0-1 mm depth of wearASTM C 944Abrasion Resistance
2-4 MPa @ 3-12 hrs.or 1-3 daysASTM C 78H-E Flex. Strength
20-30 MPa @ 3-12 hrs.or 1-3 daysASTM C 39H-E Comp. Strength
40-140 MPa @ 28 to 91 daysASTM C 39High Strength
Criteria that may be specifiedTest MethodProperty
High-Performance Concrete
Selected Properties of High-Performance Concrete (2)
Less than normal concreteASTM C 512Low creep
Less than 400 millionthsASTM C 157Low shrinkage
Rating 0-1 or mass loss 0 to 0.5 kg/m3 after 50-300 cyclesASTM C 672High resistance to
deicer scaling
Durability Factor 95-100 @ 300 -1000 cycles
ASTM C 666 Procedure A
High resistance toF/T damage
More than 40 GPaASTM C 469High Mod.of Elast. (E)
0.1% max. exp. @ 6 mos.ASTM C 1012Sulphate attack
No deterioration after 1 yr.sat. solution in wet/dry environment
Resistance to chemical attack
1000 x 10-13 m/sWood, Wilson, LeekLow diffusion coeff.
Criteria that may be spec.Test MethodProperty
High-Performance Concrete
High-Early-Strength Concrete
■ High-early compressive strengthASTM C 39 (AASHTO T 22)20 to 28 MPa (3000 to 4000 psi) at 3 to 12 hours or 1 to 3 days
■ High-early flexural strengthASTM C 78 (AASHTO T 97)2 to 4 MPa (300 to 600 psi) at 3 to 12 hours or 1 to 3 days
High-Performance Concrete
High-Early-Strength Concrete
■ Type III or HE high-early-strength cement
■ High cement content 400 to 600 kg/m3
(675 to 1000 lb/yd3)■ Low water-cementing materials ratio
(0.20 to 0.45 by mass)■ Higher freshly mixed concrete
temperature■ Higher curing temperature
May be achieved by —
High-Performance Concrete
High-Early-Strength Concrete
■ Chemical admixtures■ Silica fume (or other
supplementary cementing materials)
■ Steam or autoclave curing■ Insulation to retain heat of
hydration■ Special rapid hardening cements
May be achieved by —
High-Performance Concrete
Strength Data for Fast-Track Bonded Overlay
2.5 (359)5.7 (830)40.7 (5900)28 days2.1 (309)5.0 (722)34.2 (4960)7 days2.1 (302)4.2 (604)23.9 (3467)24 hours1.6 (225)3.4 (494)17.6 (2546)12 hours1.4 (200)2.7 (393)13.0 (1883)8 hours1.1 (160)2.0 (287)7.0 (1020)6 hours0.9 (120)0.9 (126)1.7 (252)4 hours
AgeBond strength,
MPa (psi)Flexural strength,
MPa (psi)Compressive strength,
MPa (psi)
High-Performance Concrete
Strength Development of HE Strength Concrete
Cement = 390 kg/m3
(697 lb/yd3) w/c = 0.46
High-Performance Concrete
Strength Development of HE Strength Concrete
Cement = 504 to 528 kg/m3
(850 to 890 lb/yd3) w/c = 0.46
High-Performance Concrete
High-Strength Concrete■ 90% of R/M concrete
20 MPa - 40 MPa @ 28-d (most 30 MPa – 35 MPa)
■ High-strength concrete by definition —28 day – compr. strength≥ 70 MPa (10,000 psi)
High-Performance Concrete
High-Strength Concrete Materials
■ Base selection on: ◆ mortar-cube tests◆ comparative concrete strengths at 28,
56, 91 days■ Use cement yielding highest concrete
strength at extended ages (91-days)■ Cement should have min. 7-day mortar
cube strength of 30 MPa (4350 psi)■ Trial mixture with cement contents
between 400 and 550 kg/m3 (675 and 930 lb/yd3)
Cements —
High-Performance Concrete
High-Strength Concrete Materials
■ 9.5 - 12.5 mm (3/8 - 1/2 in.) nominal maximum size gives optimum strength
■ Combining single sizes for required grading allows for closer control and reduced variability in concrete
■ 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 —
High-Performance Concrete
High-Strength Concrete Materials
■ Fly ash, silica fume, or slag often mandatory
■ Dosage rate 5% to 20% or higher by mass of cementing material.
■ Some specs. – silica fume 10% max.
Supplementary Cementing Materials —
High-Performance Concrete
High-Strength Concrete Materials
■ Use of water reducers, retarders, HRWRs, or superplasticizers —mandatory in high-strength concrete
■ Air-entraining admixtures not necessary or desirable in protected high-strength concrete.
◆ Air is mandatory, where durability in a freeze-thaw environment is required ie. bridges, piers, parking structures
◆ Recent studies: ★ w/cm ≥ 0.30—air required ★ w/cm < 0.25—no air needed
Admixtures —
High-Performance Concrete
High-Strength Concrete
■ Central Plant or Truck Mixers■ Truck mixing — reduce loads to
90% of rated capacity■ Prequalification of concrete
suppliers is recommended■ 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 —
High-Performance Concrete
High-Strength Concrete
■ Delays in delivery and placing must be eliminated
■ Consolidation very important to achieve strength
■ Slump generally 180 to 220 mm (7 to 9 in.)
■ Little if any bleeding—fog or evaporation retarders have to be applied immediately after strike off to minimize plastic shrinkage and crusting
■ 7 days moist curing
Placing, Consolidation, and Curing
High-Performance Concrete
Mix Proportions and Properties of High-Strength Concrete
0.220.29Water to cementing materials ratio
C + SFC + SF + FA
11792Compressive strength, 28d, MPa124105Compressive strength, 91d, MPa
254248Slump, mm
1.461.05Retarder, Type D, liters/m3
56.549.9Modulus of elasticity, 91d, GPa527677Drying shrinkage, 369d, millionths
20.1111.6HRWR Type F, liters/m3
—59Fly ash, kg/m3
8924Silica fume, kg/m3
564475Cement, Type I, kg/m3
High-Performance Concrete
Mix Proportions and Properties of High-Strength Concrete
0.220.29Water to cementing materials ratio
C + SFC + SF + FA
17,00013,300Compressive strength, 28d, psi18,03015,170Compressive strength, 91d, psi
109.75Slump, in.
3827Retarder, Type D, fl oz/yd3
8.207.24Modulus of elasticity, 91d, million psi527677Drying shrinkage, 369d, millionths
520300HRWR Type F, fl oz/yd3
—100Fly ash, lb/yd3
15040Silica fume, lb/yd3
950800Cement, Type I, lb/yd3
High-Performance Concrete
■ Cement: (865 lb/yd3)■ w/c: 0.25■ Silica fume: (72 lb/yd3)■ Fine aggr.: (1155 lb/yd3)■ HRWR: (420 oz/yd3)■ 28d strength: (17,200 psi)■ 91d strength: (21,000 psi)
■ Cement: 513 kg/m3
■ w/c: 0.25■ Silica fume: 43 kg/m3
■ Fine aggr.: 685 kg/m3
■ HRWR: 15.7 L/m3
■ 28d strength: 119 MPa■ 91d strength: 145 MPa
Two Union Square Seattle, 1988
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
High-Performance Concrete
High-Durability Concrete
■ Abrasion Resistance■ Blast Resistance■ Permeability■ Carbonation■ Freeze-Thaw Resistance■ Chemical Attack■ Alkali-Silica Reactivity
(helps combat)■ Corrosion rates of rebar
(high resistivity)
Durability Issues That HPC Can Address
High-Performance Concrete
■ Cement: 398 kg/m3 (671 lb/yd3)■ Fly ash: 45 kg/m3 (76 lb/yd3)■ Silica fume: 32 kg/m3 (72 lb/yd3)■ w/c: 0.30■ Water Red.: 1.7 L/m3 (47 oz/yd3)■ HRWR: 15.7 L/m3 (83 oz/yd3)■ Air: 5-8%■ 91d strength: 60 MPa (8700 psi)
High-Durability ConcreteConfederation Bridge, Northumberland Strait, Confederation Bridge, Northumberland Strait, Prince Edward Island/New Brunswick, 1997Prince Edward Island/New Brunswick, 1997
High-Performance Concrete
Self-Consolidating Concrete
■ developed in 1980s — Japan■ Increased amount of
◆ Fine material (i.e. fly ash or limestone filler)
◆ HRWR/Superplasticizers■ Strength and durability same as
conventional concrete
Self-consolidating concrete (SCC) also known as self-compacting concrete —flows and consolidates on its own
High-Performance Concrete
Portland cement (Type I) 297 kg/m3 (500 lb/yd3)
Slag cement 128 kg/m3 (215 lb/yd3)
Coarse aggregate 675 kg/m3 (1,137 lb/yd3)
Fine aggregate 1,026 kg/m3 (1,729 lb/yd3)
Water 170 kg/m3 (286 lb/yd3)
Superplasticizer ASTM C 494, Type F (Polycarboxylate-based) 1.3 L/m3 (35 oz/yd3)
AE admixture as needed for 6% ± 1.5% air content
SCC for Power Plant in Pennsylvania—Mix Proportions
High-Performance Concrete
Reactive-Powder Concrete (RPC)■ Properties:
◆ High strength — 200 MPa(can be produced to 810 MPa)
◆ Very low porosity
■ Properties are achieved by:◆ Max. particles size ≤ 300 µm◆ Optimized particle packing◆ Low water content◆ Steel fibers◆ Heat-treatment
High-Performance Concrete
Mechanical Properties of RPC
1.227510-12 m2/sAbrasion02mmCarbonation
10090RDFFreeze-thaw30<1103 J/m2Fracture Toughness
60 (8.7 x 106)40 (5.8 x 106)GPa (psi)Modulus of Elasticity8 (1160)MPa (psi)Tensile strength40 (5800)7 (1000)MPa (psi)Flexural strength
200 (29,000)80 (11,600)MPa (psi)Compressive strength
RPC80 MPaUnitProperty
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