Question

Modular ratio $m$ for M25 grade of concrete is

• A. $18.67$
• B. $13.33$
• C. $10.98$
• D. None

Answer 1

The correct option is C $10.98$

Modular ratio is defined as the ratio of modulus of Steel to the modulus of concrete.
$[m=\frac{E_S}{E_C}]$
As per $IS:456-1978$
$[m=\frac{280}{3{\sigma }_{cbc}}]$
${\sigma }_{cbc=}$Permission compressive stress in concrete
So, far $M25$ Grade of concrete ${\sigma }_{cbc}=8.5$
$m=\frac{280}{3\times 8.5}$
$m=10.98$