An 8 ft square footing is subjected to a contact pressure of

An 8 ft square footing is subjected to a contact pressure of 2000 psf. The unit weight of the soil supporting the footing is estimated to be 110 pcf. What is the minimum depth of the test boring needed?

Solution

From terzaghi ultimate bearing capacity formula

contact pressure = D*unit weight*1

D= 2000/110

=18 ft.