ABSTRACT
Tomodel the rough interface between the side of the footing and the soil, interface elements along the foundation base are assigned an equal normal and shear stiffness of 105 kN/m3 and an undrained strength of either 20 kPa in the case of soft clay lying at the surface, or 200 kPa in the case of strong clay being present at the surface. The footing is considered to be rigid and the loading is modelled by applying increments of uniform vertical displacement to the nodes located at the top of the interface elements. The ultimate footing load is then obtained by summing the vertical reactions of the nodes which have been subjected to this displacement.
