Question

A 4 m thick layer normally consolidated clay has average e = 1.3. Its compression index is 0.6 and coefficient of consolidation is $1m^2/yr$. If the increase in vertical pressure due to foundation load on the clay layer is equal to existing effective overburden pressure, the change in the thickness of the clay layer in mm.

• A. 314

Answer 1

The correct option is A 314

e = 1.3

$C_c=0.6$

$C_V=1m^2/yr$

$\Delta H=\frac{C_c{H}_0}{1+e_0}lo{g}_{10}\left(\frac{\overline{{\sigma }_0}+\Delta \overline{\sigma }}{\overline{{\sigma }_0}}\right)$

$=\frac{0.6\times 4}{1+1.3}lo{g}_{10}\left(\frac{\overline{{\sigma }_0}+\overline{{\sigma }_0}}{\overline{{\sigma }_0}}\right)$

= 0.314 m

= 314 mm