Question

A rectangular beam of depth d is under bending. Load has been gradually increased when the top fibre has obtained five times the strain at the first yield. What depth of the beam will still respond by elastic conditions?

• A. 0.16 d
• B. 0.20 d
• C. 0.25 d
• D. 0.40 d

Answer 1

The correct option is B 0.20 d


$\frac{x}{e_y}=\frac{d/2}{5e_y}$

$\Rightarrow$ $x=0.1d$

Depth of beam responding under elastic condition = 2x

$=2\times 0.1d=0.2d$