GATE 2019 CE (CE1) – Question 35
A concentrated 500 kN load acts on an elastic half-space. According to Boussinesq’s theory, find the ratio of increases in vertical normal stress at depths 2 m and 4 m directly below the load.
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: 4 to 4
Explanation
Directly below a point load, Boussinesq’s result is $\Delta\sigma_z=3Q/(2\pi z^2)$. Constants and load cancel in the ratio: $\Delta\sigma_z(2)/\Delta\sigma_z(4)=(4/2)^2=$ **4**.