Effect of soil structure interaction on the seismic response of piled supported structures

Document Type : Original research papers

Authors

1 Civil Engineering Department, Faculty of Engineering, Delta University for Science and Technology, Gamasa, P.O. Box 11152, Egypt

2 Faculty of Engineering, Delta University for Science and Technology, Egypt.

3 Civil Engineering Department, Faculty of Engineering at Shoubra, Benha University, Shoubra, P.O. Box 11629, Egypt

Abstract

The presence of liquefiable soil poses significant challenges for earthquake-resistant structure design. A substantial portion of previous research has overlooked soil-structure interactions in their analyses. However, during intense seismic activity, soil nonlinearity and separation at the soil-foundation interface can profoundly affect piled supported structures' response. Therefore, this study employs direct time-domain analysis to appropriately incorporate soil nonlinearity. A finite element model was developed using PLAXIS 2D under plain strain conditions. The PM4Sand model, renowned for simulating liquefaction behaviour in sand layers, was selected to represent the liquefiable layer. Nonetheless, the PM4Sand model has limitations in accurately capturing initial stress conditions. To address this, the Hardening Soil model with small-strain stiffness (HSS) was integrated for precise determination of initial stresses within the soil profile. The El Centro earthquake was used as the input ground motion. The findings are presented in terms of the pore water pressure ratio. The study reveals higher pore pressure ratios for piled-raft foundations compared to raft foundations alone. This distinction diminishes with increasing foundation depth, likely due to reduced inertial forces at greater depths. This observation underscores the crucial importance of accounting for soil-structure interaction in foundation analysis for structures situated on liquefiable soils.

Keywords

Main Subjects

Delta University Scientific Journal
Volume 7, Issue 3
Special Issue DU- IECRI 2024 Second International Engineering Conference on Research and Innovation Faculty of Engineering, Delta University, Egypt
November 2024
Pages 126-141

Files

Share

How to cite

Statistics