Question

A plate load test was conducted in sand on a 300 mm diameter plate. If the plate settlement was 5 mm at a pressure of 100 kPa, the settlement (in mm) of a 5 m $\times$ 8 m rectangular footing at the same pressure will be

• A. 9.4
• B. 18.6
• C. 12.7
• D. 17.8

Answer 1

The correct option is D 17.8

For sandy soil,

$\frac{S_f}{S_p}={\left[\frac{B_f}{B_p}\left(\frac{B_p+0.3}{B_f+0.3}\right)\right]}^2$

$\frac{S_f}{5}={\left[\frac{5}{0.3}\left(\frac{0.3+0.3}{5+0.3}\right)\right]}^2$

$S_f=17.8mm$

Note : for clay soil.

$\frac{S_f}{S_p}=\frac{B_f}{B_p}$