Effect of Soil-Structure Interaction on the Seismic Response of Existing Low and Mid-Rise RC Buildings

Ibrahim Oz,Ali Kalkan,Sevket Murat Senel,Mehmet Palanci

doi:10.3390/app10238357

Abstract

Reconnaissance studies performed after destructive earthquakes have shown that seismic performance of existing buildings, especially constructed on weak soils, is significantly low. This situation implies the negative effects of soil-structure interaction on the seismic performance of buildings. In order to investigate these effects, 40 existing buildings from Turkey were selected and nonlinear models were constructed by considering fixed-base and stiff, moderate and soft soil conditions. Buildings designed before and after Turkish Earthquake code of 1998 were grouped as old and new buildings, respectively. Different soil conditions classified according to shear wave velocities were reflected by using substructure method. Inelastic deformation demands were obtained by using nonlinear time history analysis and 20 real acceleration records selected from major earthquakes were used. The results have shown that soil-structure interaction, especially in soft soil cases, significantly affects the seismic response of old buildings. The most significant increase in drift demands occurred in first stories and the results corresponding to fixed-base, stiff and moderate cases are closer to each other with respect to soft soil cases. Distribution of results has indicated that effect of soil-structure interaction on the seismic performance of new buildings is limited with respect to old buildings.

Highlights

The determination of the seismic performance of existing buildings has gained very much interest in recent years, and today there are a greater number of specifications and regulations containing provisions on this issue [1]
Percentage of Collapses constructions (Figure 5) suppress the deteriorating effects of soil-structure interaction (SSI) and the effect of interaction becomes limited on new buildings
Modern seismic design indicates that the relative effectconstructed of SSI is much moreand significant lower story

Summary

Introduction

The determination of the seismic performance of existing buildings has gained very much interest in recent years, and today there are a greater number of specifications and regulations containing provisions on this issue [1]. Advances and experiences in earthquake engineering, reconnaissance surveys after strong earthquakes and academical studies about soil-structure interaction (SSI) have shown that old buildings designed by limited knowledge are far from meeting the current standards and performance objectives of new designs. Over the last two decades the widespread use of displacement-based methods, which include nonlinear calculations such as static pushover analysis, provide to investigate SSI beyond the elastic limits [3,4]. Realistic estimations of both displacement capacities and seismic drift demands became possible by using nonlinear analysis methods. The damage observations and detailed structural analyses have shown that SSI could significantly alter both the capacity and demand-related

Objectives

Results

Conclusion