Seismic Performance Evaluation of a Multistorey Building with Soft Storey

Soft storey is a storey in which the stiffness is less than 70% of the storey above or less than 80% of the combined stiffness of the storeys above. In a multi-storied building, soft storey is adopted to accommodate parking which is an unavoidable feature. This open ground storey is vulnerable to collapse during earthquake. Soft storey in a building causes stiffness irregularity in a structure. In high rise building or multi storey building, soft storey construction is a typical feature because of urbanization and the space occupancy considerations. These provisions reduce the stiffness of the lateral load resisting system and a progressive collapse becomes unavoidable in a severe earthquake for such buildings due to soft storey. This storey level containing the concrete columns which were unable to provide adequate shear resistance, hence damage and collapse are most often observed in soft story buildings during the earthquake. Infill wall plays an important role in providing lateral stiffness to the building. In this paper an industrial building is selected for the study, to study the seismic performance of soft storey buildings, there are 6 3D mathematical models have been developed using ETABS. The following parameters have been studied, storey drift, storey displacement, time period, storey shear and modes shapes. Subsequently adopting the control measures to reduce the effect of soft storey in terms..