Question

The contact pressure of a footing was found to be 85 kN/m^2 for a load of 212.5 kN. What will be the contact area?

(a) 1 m^2

(b) 2.5 m^2

(c) 3 m^2

(d) 3.5 m^2

I got this question in an online quiz.

My question is from Stress Distribution topic in chapter Stress Distribution of Geotechnical Engineering I

Answer 1

Right answer is (b) 2.5 m^2

To elaborate: Given,

contact pressure=85 kN/m^2

load of 212.5 kN

\(Contact\, pressure=\frac{normal\, load}{true \,contact\, area}\)

∴ \(true \, contact \,area=\frac{normal load}{contact pressure}\)

Area=212.5/85=2.5 m^2.