Calculation of the settlement of pile foundations taking into account the influence of soil liquefaction

Abstract

Pile foundations are considered one of the most common foundation solutions for the construction of buildings and structures in difficult geotechnical conditions, including in seismic areas. However, during earthquakes specific processes often occur that negatively affect the interaction of piles with the surrounding soil. Soil liquefaction is one of the most difficult problems in geotechnics. Many historical cases show that buildings and structures on pile foundations are collapsed completely when the surrounding soil liquefies. One of the reasons is the increase in settlement of the foundation after soil liquefaction.Unlike the liquefaction potential assessment, or liquefaction-induced settlement of structures on shallow foundations, which are discussed by many researchers, the settlement of pile foundations after soil liquefaction has not been studied extensively. This paper presents the calculation of the settlement of pile foundations in different cases, with and without taking into account the influence of soil liquefaction, based on the hypothesis that the additional downward loads due to self-compaction of the liquefiable soil layers have an effect on piles. The analysis method in this study refers to the finite element method via PLAXIS 3D software. Finally, a brief comparison of the calculation results in the different considered cases is presented. The comparison shows how much the foundation settlement can increase if the influence of soil liquefaction is taken into account based on the suggested hypothesis. This paper provides a useful calculation and importance of further researches of liquefaction-induced settlement of pile foundations for seismic design.