Chapter 7, Problem 7.20QPP

A certain column carries a vertical downward load of 424 k. It is to be supported on a 3 ft deep rectangular footing. Because of a nearby property line, this footing may be no more than 5 ft wide. The soil beneath this footing is a silty sand with the following properties: $\gamma =124{\text{lb/ft}}^{\text{3}},c\text{'}=50{\text{lb/ft}}^{\text{2}},$ and $\varphi \text{'}=34°.$ The groundwater table is at a depth of 6 ft below the ground surface. use ASD and the spreadsheet developed in Problem 7.19 to compute the footing length required for a factor of safety of 3.0.