Abstract

In geotechnical mediums where the bearing capacity of upper layers of soil is not suitable for use of the shallow foundations, piles are usually used as deep foundations to transfer loads to the stronger lower layers. Here, the seismic behavior of single pile and pile group constructed in saturated soft kaolin clay under three different earthquakes using Abacus 3D software is investigated. The aluminum material considering the linear elastic model has been used for the piles, and the nonlinear kinematic hardening model with Von Mises failure criterion has been considered for clay. This model can consider the soil stiffness degradation by increasing the number of cyclic loading. Three different methods have been used to calibrate the model parameters, two of them are new methods. In all calibration methods, the cyclic shear and undrained cyclic triaxial tests are used. The results obtained from the numerical analysis of the soil-pile model are in relatively good agreement with the centrifuge model results. According to the results, the variation of earthquake frequency and intensity affects the bending moment created along the pile and also the distance between piles in a pile group affects the amount of the interaction between them.

Highlights

  • In case of low bearing capacity of soil for use of shallow foundations, deep foundations are used

  • It is worth noting that for the first time the seismic behavior of the pile group in the soft soil has been investigated using the nonlinear kinematic hardening model. e soil studied in this research is saturated soft kaolin clay and all analyses are performed using the finite element method in 3D Abaqus. ree types of earthquakes with different peak ground acceleration of 0.07 g, 0.1 g, and 0.22 g considering tied degrees of freedom (TDOF) boundary were used and the linear elastic model is considered for aluminum piles and caps

  • The aluminum material considering the linear elastic model has been used for the piles, and an advanced nonlinear kinematic hardening model has been considered for soft kaolin clay. ree different calibration methods have been used to calibrate the constitutive model parameters where the second and third methods are the new methods presented in this study and the results of the numerical models were in good agreement with the results of the centrifuge model

Read more

Summary

Introduction

In case of low bearing capacity of soil for use of shallow foundations, deep foundations (pile foundations) are used. Due to the construction of some structures in earthquake areas, investigating the seismic behavior of piles, especially in soft soils, has become a challenge for geotechnical engineers. The nonlinear kinematic hardening constitutive model and the procedure of calibrating its parameters in three different methods where second and third methods are new have been investigated. E results obtained from numerical analysis using three different methods of all parameters calibration were compared with the centrifuge results [15] to investigate the seismic behavior of the pile inside the soil. It is worth noting that for the first time the seismic behavior of the pile group in the soft soil has been investigated using the nonlinear kinematic hardening model. It is worth noting that for the first time the seismic behavior of the pile group in the soft soil has been investigated using the nonlinear kinematic hardening model. e soil studied in this research is saturated soft kaolin clay and all analyses are performed using the finite element method in 3D Abaqus. ree types of earthquakes with different peak ground acceleration of 0.07 g, 0.1 g, and 0.22 g considering tied degrees of freedom (TDOF) boundary were used and the linear elastic model is considered for aluminum piles and caps

Constitutive Model and Calibration
Results and Discussion
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call