Question

A point load of 650 kN is applied on the surface of a thick layer of clay. Using Boussinesq's elastic analysis, what is approximate value of the estimated vertical stress at a depth 2 m and a radial distance of 1.0 m from the point of application of load?

• A. $55kN/m^2$
• B. $44kN/m^2$
• C. $41kN/m^2$
• D. $37kN/m^2$

Answer 1

The correct option is B $44kN/m^2$

According to Boussinesq's theory,
${\sigma }_z=\frac{3Q}{2\pi z^2}\frac{1}{[1+(r/z{)}^2{]}^{5/2}}$
$=\frac{3\times 650}{\pi \times 2^2{[1+{\left(\frac{1}{2}\right)}^2]}^{5/2}}$
$=44.4kN/m^2$