Article

Sharif

, 28:6

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

تاثیر تغییر مشخصات لایه‌های خاک بر پاسخ سیستم خاک-شمع تحت بار زلزله

  • S. Mir-MohammadrezaeiAffiliated withFaculty of Engineering & Technology, Tarbiat Modares University
  • , A. GolshaniAffiliated withFaculty of Engineering & Technology, Tarbiat Modares University Email author 

THE EFFECT OF SOIL MECHANICAL PROPERTIES ON RESPONSE OF SOIL-PILE SYSTEMS UNDER EARTHQUAKE LOADING

Abstract

In the last few years, although considerable progress has been made in developing methods of analysis and understanding of phenomena related to dynamic soil-pile interaction, much has still to be learned through systematic parametric studies. Due to the progressing knowledge and capabilities of computer software and hardware, a significant amount of study has been conducted to investigate the effect of changes in environmental conditions around the piles on the soil-pile behavior under dynamic analysis. The necessity of evaluating the effects of changes in the soil profile around the pile has significant importance. In this research, dynamic interaction between pile and soil has been examined, and the current methods were introduced. With the aim of a better understanding of the problem, first, a brief review was made on previous research. Then, the behavior of pile-soil under earthquake load and with geotechnical problems has been discussed using Finite Difference Software i.e., FLAC3D. Through using different types of accelerogram, dynamic analysis was conducted to evaluate the effective factors on interaction, such as a comparison of elastic and Mohr-Coulomb elastoplastic behavior. In order to obtain the above-mentioned goals, kinematic effects are described by frequency dependence on the transfer function. The transfer function is defined in the frequency domain as the relative movement of the foundation to a free field in the absence of a structure. The obtained results from analysis are presented as an acceleration time history, as well as the Fast Fourier Transformation of the acceleration of a head pile in relation to a free field in the frequency domain. Maximum shear force and flexural moment applied to the pile have been compared in different modeling. Based on the analysis results, the difference in the stiffness of soil layers may have an appreciable influence on the soil-pile interaction. It should be mentioned that the condition of two-layer soil is more critical than one-layer soft soil, and the lowest interaction, displacement and maximum moment were observed in one-layer soil.

Key words

dynamic analysis kinematic interaction soil-pile behavior earthquake loading fast fourier transformation acceleration time history