Flexural Response of Pile Foundation in Liquefiable Soil Using Finite-Difference Formulation Following Pseudostatic Approach

The collapse of pile-supported structures, especially in liquefiable soils, is still a major concern to the geotechnical earthquake engineers. In the last few decades, extensive research has been carried out to analyse the behaviour of pile foundations under seismic conditions. However, there are only a few codal provisions that take into account the effects of liquefaction and liquefaction-induced ground movement considering the developments made so far. The prime objective of this paper is to stipulate a simplified methodology to assess the flexural response of a pile foundation under liquefied ground conditions considering the latest developments. In this study, a finite-difference-based formulation is devised to analyse the flexural response of a single pile foundation. The formulation is capable of evaluating the performance of the pile foundation under both the inertial and kinematic loading conditions through the pseudostatic approach. The implemented formulation has been validated with the established theoretical method, field test results and one past case history. Moreover, a detailed systematic investigation is presented for the evaluation of the flexural response of a single pile foundation embedded in a liquefiable site in Patna city, India, considering recently developed bending and buckling criteria in tandem. It is highlighted in the study that the bending and buckling collapse mechanism may be avoided by suitable selection of geometric configurations of pile ignoring the frictional resistance in the liquefaction zone.