ABSTRACT

Aggregate, coarse 1500

Stone, crushed 1350

Ballast, all-in 1800

Concrete 2450

Suitability of mixes

Precast work in small sectional areas 1:1:2

Watertight reinforced concrete structures 1:1.5:3

Normal reinforced concrete work 1:2:4

Mass unreinforced concrete work 1:2.5:5

Rough concrete work 1:3:6

290 Concrete work

Concrete mixes (per m3) Mix Cement Sand Aggregate Water

t m3 m3 litres

1:1.5:3 0.37 0.50 0.80 185

1:2.5:5 0.25 0.55 0.85 166

Grade

20/20 0.32 0.62 1.20 170

25/20 0.35 0.60 1.17 180

30/20 0.80 0.59 1.11 200

7/40 all-in 0.18 - 1.95 150

20/20 all-in 0.32 - 1.85 170

25/20 all-in 0.36 - 1.75 180

Steel bar reinforcement

Diameter Nominal weight Length Sectional area mm kg/m m/tonne mm 2

6 0.222 4505 28.30 8 0.395 2532 50.30

10 0.616 1623 78.50 12 0.888 1126 113.10 16 1.579 633 201.10 20 2.466 406 314.20

Diameter mm

25 32 40 50

Ref.