SEISMIC VULNERABILITY ASSESSMENT OF A RESIDENTIAL STEEL BUILDING CONSIDERING SOIL STRUCTURE INTERACTION

Abstract

The current practice for the design of the building structure is done by considering the footing as fixed footing. Designers approach fixed footing as the basis for design and hence neglect the effect of Soil Structure Interaction (SSI). This research focuses to understand the effect of SSI on the response of steel structure through the generation of validated models in SAP2000. Validation of SSI effect on steel structure is based on the experimentation done by Xiong et al. (2016). The validated model was utilized to study four real-scale residential steel buildings as case study. The bare frame is modelled and analyzed, using finite element method under two different boundary condition i.e., fixed base and SSI. From the results obtained, it shows that SSI clearly affects base shear and time period of the building. The vulnerability assessment of the case study prototype buildings is also done. The fragility curves generation approach is based on the concept of using pushover curve for capacity of the building and the demand is the obtained from response spectra of the building code. The fragility analysis highlights that SSI base models are relatively vulnerable in comparison to the fixed base models.