Influence of Inherent Soil Variability on Seismic Response of Structure Supported on Pile Foundation

Abstract

Traditional seismic design is limited to fixed base assumption of superstructure. Such perception proved to be misleading from the post facto analysis of different failure case studies. In addition, inherent variability of soil parameters may lead to a considerable effect on seismic response of foundation and superstructure elements. Incorporation of shear strength variability of soil along with dynamic soil structure interaction phenomenon may result in increased or decreased transmitted shear to the pile as compared to fixed base shear which may lead to unsafe or over-safe pile design. The present study assesses the influence of shear strength variability of soil on seismic response of pile foundation considering soil nonlinearity. Probabilistic analysis is performed by Monte Carlo simulation technique. The study infers that variability of shear strength parameters of soil has significant effect on response of pile embedded in clay, while such effect is marginal in sandy soil. However, it is also observed that adoption of different pile�soil interaction modeling contributes variability in probabilistic response of pile. Finally, a case study shows the importance of shear strength variability of soil on increase in percentage of steel requirement in pile foundation. � 2019, King Fahd University of Petroleum & Minerals.