SSC JE Civil Engineering 30-Oct-2020 Shift 2 Paper

Concept:
Tensile strength of the concrete:
As per IS 456: 2000, the estimated flexural tensile strength ( ${\mathrm{f}}_{\mathrm{cr}}$ ) of concrete is given by:
Flexural Tensile strength $={\mathrm{f}}_{\mathrm{cr}}=0.7\sqrt{{\mathrm{f}}_{\mathrm{ck}}}$
Where
${\mathrm{f}}_{\mathrm{ck}}$ = Characteristic strength of the concrete in N/ ${\mathrm{mm}}^2$
Calculations:
${\mathrm{f}}_{\mathrm{ck}}=36\mathrm{N}∕{\mathrm{mm}}^2$
Flexural Tensile strength,
${\mathrm{f}}_{\mathrm{cr}}=0.7\sqrt{36}$
${\mathrm{f}}_{\mathrm{cr}}=0.7\times 6$
${\mathrm{f}}_{\mathrm{cr}}=4.2\mathrm{N}∕{\mathrm{mm}}^2$