Modified Pseudo-dynamic Bearing Capacity of Shallow Strip Footing Considering Fully Log-Spiral Passive Zone with Global Center

Abstract

The subject seismic bearing capacity is one of the most important aspects of geotechnical earthquake engineering. As the existing pseudo-dynamic method has certain drawbacks, this paper presents a modified pseudo-dynamic approach to evaluate the seismic bearing capacity of shallow strip footing resting on c–Φ soil considering the log-spiral failure mechanism. Since damping is present in all materials, more realistic results can be obtained by modeling the soil as a visco-elastic material. Here, the passive failure region is considered a fully log-spiral zone with an arbitrary location of the center of log-spiral. A single seismic bearing capacity coefficient (Nγe) is evaluated for the simultaneous resistance of unit weight, surcharge and cohesion, which is more practical to simulate the field failure mechanism. The effects of soil and seismic parameters are taken into account to evaluate the seismic bearing capacity of the foundation. The results obtained from the present analysis are presented in both tabular and graphical non-dimensional form. Results are thoroughly compared with the existing values in the literature, and a reasonably good agreement is found with the existing studies.