High-Performance Concrete - Design and Control of Concrete Mixtures - page 297

Table 17-5 (Inch-Pound Units). Mixture Proportions and Properties of Commercially Available High-Strength
Concrete ( Burg and Ost 1994 )

Mix number

Units per yd 3 1 2 3 4 5 6

Cement, Type I, lb 950 800 820 950 800 551

Silica fume, lb — 40 80 150 125 45

Fly ash, lb — 100 — — 175 147

Coarse aggregate SSD ( 1 ⁄ 2 in.
crushed limestone), lb

1800 1800 1800 1800 1800 1890

Fine aggregate SSD, lb 1090 1110 1140 1000 1000 1251

HRWR Type F, fl oz 300 300 290 520 425 163

HRWR Type G, fl oz — — — — — 84

Retarder, Type D, fl oz 29 27 25 38 39 —

Water to cementing materials ratio 0.28 0.29 0.29 0.22 0.23 0.32

Fresh concrete properties

Slump, in. 7 3 ⁄ 4 9 3 ⁄ 4 8 1 ⁄ 2 10 9 1 ⁄ 4 8

Density, lb/ft 3 153.0 153.1 151.9 155.2 153.5 153.2

Air content, % 1.6 0.7 1.3 1.1 1.4 1.2

Concrete temp., °F 75 75 65 63 62 74

Compressive strength, 4 x 8-in. moist-cured cylinders

3 days, psi 8,220 7,900 7,970 10,430 7,630 6,170

7 days, psi 9,660 10,230 10,360 13,280 11,150 9,170

28 days, psi 11,460 13,300 13,070 17,000 14,530 12,270

56 days, psi 12,230 13,660 13,840 17,630 16,760 —

91 days, psi 12,800 15,170 13,950 18,030 17,350 13,310

182 days, psi 14,110 15,160 14,140 18,590 17,400 —

426 days, psi 14,910 17,100 14,560 19,230 17,290 —

1085 days, psi 16,720 17,730 16,650 21,750 19,190 —

Modulus of elasticity in compression, 4 x 8-in. moist-cured cylinders

91 days, million psi 7.34 7.24 7.27 8.20 7.75 6.95

Drying shrinkage, 3 x 3 by 11.5-in. prisms

7 days, millionths 193 123 100 87 137 —

28 days, millionths 400 287 240 203 233 —

90 days, millionths 573 447 383 320 340 —

369 days, millionths 690 577 520 453 467 —

1075 days, millionths 753 677 603 527 523 —

recommendations for preconstruction laboratory and
field-testing procedures described in ACI 363.2 are essen-
tial. Concrete with a design strength of 131 MPa (19,000
psi) has been used in buildings (Fig. 17-5).
Traditionally, the specified strength of concrete has
been based on 28-day test results. However, in high-rise
concrete structures, the process of construction is such that
the structural elements in lower floors are not fully loaded
for periods of a year or more. For this reason, compressive
strengths based on 56- or 91-day test results are commonly
specified in order to achieve significant economy in mate-
rial costs. When later ages are specified, supplementary

cementing materials are usually incorporated into the con-
crete mixture. This produces additional benefits in the
form of reduced heat generation during hydration.
With use of low-slump or no-slump mixes, high-
compressive-strength concrete is produced routinely
under careful control in precast and prestressed concrete
plants. These stiff mixes are placed in ruggedly-built
forms and consolidated by prolonged vibration or shock
methods. However, cast-in-place concrete uses more
fragile forms that do not permit the same compaction
procedures, hence more workable concretes are necessary
to achieve the required compaction and to avoid segrega-