The Effect of the L/D Ratio of Pile Group Using the Equivalent Pier Method Including Interaction

Abstract

The behavior of the pile under the load is governed number of piles in the group, pile spacing, pile length, pile diameter and type of the soil and its interaction with pile. In order to implement the interaction effect, the interfaces between soil and pile is needed to model which found to be very tedious, complex and numerically costly. To overcome this complication, the attempt is made to provide an easy to model the interaction problem. In this study, the equivalent pier method has been introduced to model the pile soil structure interaction system, where the pile group has been replaced with the single equivalent pier. In this study the L-shape asymmetrical pile group is modeled with a direct method using finite element procedure. The C++ program is developed using finite element procedures to achieve the dynamic analysis of the soil-pile structure interaction system. The SSI system is modeled for different L/D ratio including 10, 20, 30, 40 and 50. The responses of the system are obtained from the different L/D ratio of the pile group by carrying out the dynamic nonlinear soil structure interaction analysis of the 2001 Bhuj ground motion (M = 7.0). The responses of the SSI system have been checked for the reduced EPM configuration for the one of the mentioned L/D ratios. The results in terms of displacement and numerical statistics have been compared to the general pile layout (i.e. L/D = 20). The study concludes that the reduced EPM model offers ease to model complicated SSI system. Also, it has been observed that the EPM model has an acceptable accuracy in the responses and also numerically efficient with interaction effect under the dynamic loading condition.