Seismic Behaviour of RC Building with Multiple Soft Storey Considering Different Soil Conditions

Abstract

AbstractThe present situation, growth of multi-storey building is very high because of urbanisation all over the world. Due to urbanisation and increase in scarcity of space, it is becoming imperative to provide open-ground storey in commercial and residential buildings. Open-ground storey (OGS) is generally provided for parking, reception lobbies, communication hall, or for any other purpose. Soft storey is an irregularity which affects the behaviour of construction during earthquake. A study of structural performance of building during the past earthquakes has clearly indicated that latest trends of constructions such as soft storey are not earthquake resistant. Soft storey during earthquake plays an important role in seismic performance of the building. At the soft storey level, there is discontinuity in rigidity of structure due to lack of infill walls. Due to this discontinuity of rigidity between the floors, causes progressive collapse of structure. Present the trend is to provide multiple soft storeys in RC frame structures. Multiple soft storeys are the buildings with soft storey at multiple levels. Multiple soft storey is adopted in many buildings because it provides open space to meet architectural demands and economical demands. In this study, behaviour of RC frame building with and without soft storey considering different soil conditions is discussed. The dissertation work is carried out on G + 7 RC-framed building located in seismic zone III. In an attempt to investigate the effect of soft storey at multiple level in RC building, four different types of models are analysed considering hard soil, medium soil and soft soil conditions. Soft storey levels are altered from ground floor to top floor, and seismic analysis is performed using ETABS software. It is intended to describe the performance characteristics such as displacement, storey drift, base shear, axial force and natural period. Results show the general changing pattern of different parameters with respect to different soil conditions.KeywordsSoft storeyOpen-ground storey (OGS)Base shearResponse spectrumStorey drift