Seismic bearing capacity factors for spread foundations Available to Purchase

The effect of horizontal earthquake body forces on the bearing capacity of foundations has been examined computationally in a rigorous manner by employing the method of stress characteristics. The bearing capacity factors N_c, N_q and N_γ, due to the components of soil cohesion, ground surcharge pressure and soil unit weight respectively, have been plotted as a function of earthquake acceleration coefficient (α_h) for different values of soil friction angle (ϕ). The inclusion of earthquake body forces causes a considerable reduction in the bearing capacity factors. The bearing capacity factors N_c and N_q are seen to be approximately of the same magnitude as those reported in the literature on the basis of different solution methods. However, the obtained values of N_γ are found to be significantly smaller than the available results. The nature of the pressure distribution along the footing base and the geometry of the observed failure patterns vary with the consideration of earthquake body forces.