Seismic Bearing Capacity of an Embedded Strip Footing on Slope Using Modified Pseudo-Dynamic Method

By combining the modified pseudo-dynamic method with the lower bound finite element limit analysis technique, the bearing capacity of an embedded strip footing placed on a soil slope and under seismic loading is estimated. A series of parametric studies by varying coefficients of seismic acceleration, friction angle of soil, inclination of the slope, embedded depth of footing, and soil damping ratio is carried out. Obtained results are shown as the variation between the bearing capacity factor and considered parameters. It is found that with the increasing footing embedment, seismic bearing capacity increases considerably. The range of increment in the seismic bearing capacity of an embedded footing varies from seven to ten times that of no embedment. However, irrespective of footing embedment depth, the bearing capacity of footing reduces with increasing values of seismic acceleration coefficients. When both the horizontal and vertical seismic acceleration coefficients are considered together, seismic bearing capacity reduces more. However, it is also found that the footing bearing capacity is higher for soil with a higher damping ratio than that of the footing on a soil with a lower damping ratio. With increasing friction angle of soil, footing bearing capacity increases, but reduces with increasing slope inclination. State of stresses throughout the problem domain are plotted in the two-dimensional axes to understand the failure mechanism of slope under pseudo-dynamic loading. Results obtained from the study will be useful to the design engineers.