Square and Rectangular Footings
It is common to use square and rectangular footings for columns depending on their shapes. Bearing capacity and settlement are their basic design criteria. For obtaining bearing capacity of square and rectangular footings, the expression of bearing capacity obtained for a strip footing has been modified using suitable shape factors. Michalowski and Dawson analyzed the problem of square footing using through code FLAC and limit analysis independently. Using elasto-plastic model and finite element analysis, Zhu and Michalowski gave new suggestions for the shape factors. They found that the earlier factors modifying the contribution of cohesion and overburden are conservative. Using 3-D random finite element method (RFEM), Griffiths and Fenton developed a general probabilistic design framework for assessing settlements of rectangular footings. The analysis of rigid square footing on clay has also been done by dividing the whole area of foundation in n equal parts. Procedures for obtaining the pressure-settlement characteristics of smooth flexible and rigid rectangular footings are same.