Spectral bearing capacity analysis of strip footings under pseudo-dynamic excitation

Spectral seismic bearing capacity of strip foundations is evaluated by the limit equilibrium method (LEM). In this study, the pseudo-dynamic approach is followed to take into account seismic accelerations. The formulation of spectral pseudo-dynamic bearing capacity of strip foundations is presented for the Coulomb failure mechanism. The results are reported in the form of joint bearing capacity considering the contributions of cohesion, surcharge, and soil weight, simultaneously. A parametric study is conducted to evaluate the influence of soil friction angle, interface wall friction angle, dimensionless ratio of cohesion, depth factor, primary and shear wavelength values, amplification factor as well as the frequency on the seismic bearing capacity factor. The results of this study are shown in the form of design aids and tabular for the sake of simplicity to be used by engineers. The consistency of the results with those reported in literature shows the ability and efficiency of the methodology presented herein. It is shown that both the seismic loading characteristics and shear strength parameters affect the bearing capacity of shallow footings.