Question

What is the minimum value of individual test results $\left(inN/m{m}^2\right)$ for compressive strength compliance requirement for concrete M20 as per codal provision?

• A. $f_{ck}-1$
• B. $f_{ck}-3$
• C. $f_{ck}-4$
• D. $f_{ck}-5$

Answer 1

The correct option is C $f_{ck}-4$

As per IS : 456-2000 the characteristic compressive strength compliance requirement are:
Grade of concrete Individual test
Results $\left(inN/m{m}^2\right)$
M15 $\ge f_{ck}-3$
M20 or above $\ge f_{ck}-4$