Nonlinear Static and Dynamic Analysis of Buildings Considering Soil Structure Interaction

Abstract

An attempt has been made during the present study to understand the behavior of reinforced concrete structures considering soil structure interaction. A multistoried frame building subjected to seismic forces are modeled and analyzed through the finite elements software program (SAP 2000 V14) which are primarily designed according to ACI 318M-11) and ASCE 7-10 Code. Both static and dynamic analysis methods are used, which may be linear and nonlinear. Recorded ground motions are used in nonlinear dynamic (time history) analysis. Analyses of frames are carried out to find the lateral displacements, drift ratios, and time period of free vibration motion of structural systems. The study reveals that soil flexibility has significant effect on the response of structures. Soil flexibility led to increase the storey drift and lateral displacement. In addition, it led to increase in neutral lateral time period of structure vibration of frame buildings especially, with soft soil stiffness. The present study also, presents a methodology to protect the structure against earthquake excitation by using rubber isolators, where decreases in the natural frequency of structure building have been observed and the presence of rubber at a location of each column led to decrease the value of axial force and shear base stress as compared with fixed-base case.

Keywords

• building structural system
• finite elements method
• nonlinear dynamic analysis
• soil
• time history analysis