SEISMIC BEHAVIOR OF HIGH-RISE STEEL BUILDING ON PILE GROUPS ACOUNTING FOR SOIL-STRUCTURE INTERACTION EFFECTS ON SOFT SOIL

Previous studies on the subject have identified seismic soil–structure interaction (SSI) as the important factors affecting structures response on soft soil during the earthquakes. In this paper, a three dimensional (3D) Finite Element Method (FEM) for the nonlinear behaviour of structure and soil are utilized. To investigate the effects of the SSI on the seismic response of the superstructures, a series of numerical simulations were conducted on 15-story building as well as six types of pile-raft foundations. The goal was to evaluate the effectives of using a piled raft and estimation of the required optimum number, location and configuration of the piles. In order to confirm the reliability of the numerical model, the validation was accomplished based on the data extracted from experimental shaking table results. Therefore, parametric studies have been conducted in order to obtain design strategies for an optimized design of piled rafts subjected to low-to-high intensity real earthquake records as input motions. The numerical results indicate a reasonable correlation between Shaking Intensity Rate (SIR) parameter and maximum interstory drift of structures. Furthermore, the performance level of structures on softened ground is a function of area replacement ratio, diameter, and length and space between piles and ground motion characteristic, so these important aspects are considered.

کلیدواژه ها:

Soil-Structure interaction ، Pile group ، High-Rise building ، Nonlinear dynamic analysis ، Finite element method