Question

To make one cubic meter of $1:2:4$ by volume concrete, the volume of coarse aggregate required is

• A. $0.95m^3$
• B. $0.85m^3$
• C. $0.75m^3$
• D. $0.65m^3$

Answer 1

The correct option is B $0.85m^3$

$1m^3$ of dry concrete $=1.54m^3$ of wet concrete
$M15=1:2:4=1+2+4=7$
$\frac{\text{Dry volume of concrete}}{\text{Wet volume of concrete}}=1.54$
Volume of cement $=1.54\times \frac{1}{7}{m}^3$
Volume of cement $=0.22m^3$
Volume of sand $=1.54\times \frac{2}{7}=0.44m^3$
Volume of aggregate $=1.54\times \frac{4}{7}=0.88m^3\square 8.85m^3$