2D and 3D Numerical Simulation of Load-Settlement Behaviour of Axially Loaded Pile Foundations

Gowthaman S,Nasvi Mcm

doi:10.12691/ajcea-5-5-2

Abstract

Reliable prediction of settlement behaviour of axially loaded piles is one of the major concerns in geotechnical engineering. Therefore, this paper focuses on the finite element solutions of load-settlement behaviour of a single pile and pile group using PLAXIS numerical package. Three different types of analysis were incorporated: a linear elastic analysis, a complete nonlinear analysis and a combined analysis. The pile case history with settlement measurements made during field pile load test was considered to validate the single pile load-settlement simulation, and the same load test result was extended to simulate the load-settlement behaviour of pile group using RATZ analytical approach. The single pile analysis results suggest that realistic load-settlement predictions can be drawn by considering complete soil as Mohr-Coulomb model at lower working loads, and incorporation of an interface zone thickness of two times pile diameter using Hardening-Soil model is required to simulate the load-settlement behaviour at higher working loads. The group pile analysis results provide a better load-settlement prediction when incorporating an interface zone thickness of pile dimeter from the pile shat using Hardening-Soil model while leaving the remaining soil as Linear-Elastic material.

Highlights

Nowadays, lot of attention has been paid on axially loaded pile foundations to construct Civil Engineering infrastructures due to their high load bearing capacity and applicability in various kinds of geological scenarios
For the same working load, settlement predicted from the Hardening Soil (HS) model of finite element model (FEM) analysis is 8.2 mm and settlement values predicted from Linear Elastic (LE) model and Mohr Coulomb (MC) model for the same working load are almost the same, and it is 6.8 mm
The Modulus obtained from the laboratory tests significantly vary from the in-situ modulus of deep soil and sometimes the difference is in the order of several times [21]

Summary

Introduction

Lot of attention has been paid on axially loaded pile foundations to construct Civil Engineering infrastructures due to their high load bearing capacity and applicability in various kinds of geological scenarios. Many researchers [5,6,7,8,9,10,11,12,13] have conducted analytical study for the vertical deformation of pile foundations using different techniques such as theoretical load-transfer curves, discrete layer approach, elastic solutions, theory of pile-soil interactions and hybrid approaches. In this method, problems have often been solved by making number of simplifying assumptions regarding the geometry and material properties [14]

Methods

Results

Conclusion