The role of soil structure interaction (SSI) on seismic response of tall buildings with variable embedded depths by experimental and numerical approaches

Abstract

The soil-structure interaction is an integral part of the seismic evaluation, especially for structures with variable embedment depths. The purpose of this work is to ensure the adequacy of the small scaling factor in the dynamic analysis and study the seismic behavior of tall building with considering variable embedment depths and soil structure interaction effects. Therefore, scaled model tests of a 15-story steel structure were performed using shaking table tests and numerical simulations. Three scaled earthquake records, namely: Chi-Chi (1999), Northridge (1994), and Kobe (1995), were selected. The numerical scaled coupled models were implemented with Plaxis 3D software and validated with the experimental observations. Afterward, the experimental and numerical results of scaled models were verified with prototype models to ensure the adequacy of the small scaling coefficient. The results generated from small-scale models derived from experimental and numerical simulations were in good agreement. In addition, these results achieved good accuracy with full-scale field conditions in the seismic analysis. Therefore, a small geometric scaling coefficient of 1:50 achieved good accuracy for buildings with embedded parts to represent the dynamic behavior of structures. Within the frame results, it is noted that the SSI has an essential role in amplifying the lateral deflection of structures compared with a fixed base and thus the embedded depths significantly affect the lateral seismic response of the considered structures.