Chapter 7, Problem 7.4QPP

A column carrying a vertical downward unfactored load of 270 k is to be supported on a 3 ft deep square spread footing. The soil beneath this footing is an undrained clay with $s_u=3,000{\text{lb/ft}}^{\text{2}}$ and $\gamma =117{\text{lb/ft}}^{\text{3}}.$ The groundwater table is below the bottom of the footing. Using the ASD method, compute the width B required to obtain a factor of safety of 3 against a bearing capacity failure.