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Top1. Introduction
The large rapidly growing urban seismic risk particularly in developing country like India is a major concern which is required to be determined and major remedial measurement should be taken urgently. This task can be performed through site specific response study for accurately predicting seismic ground motion (Kumar et al., 2018; Angina et al., 2018; Basu et al., 2017; Kumar and Krishna, 2013; Sil and Sitharam, 2013; Boominathan and Kumar, 2010) and with the ground motion structure should be designed by some modified design philosophy which will be a useful tool for cost-effective earthquake design, urban planning and preparedness.
Indian seismic code (IS-1893 (part 1), 2016) is based on force-based design of structure. However, during future seismic events, performance of the buildings is not reliable in the force-based method, as different important performance objectives like immediate occupancy (IO), collapse prevention (CP), Life safety (LS) (Merado, 2017) for different type buildings like school, hospital are not considered. Thus, the Performance Based Seismic Design (PBSD) has been used in recent days as a tool to predict seismic risk of buildings more precisely. Further, it is significant to take account of the nonlinear analysis of structures to estimate their performance during future earthquake.
Tsang et al. (2006) developed a simple procedure to compute site coefficient using single periodic approximation and to generate displacement response spectra for soil site. They argued that the developed model which is able to compute non‐linear site responses and able to construct site‐specific response spectra can be incorporated into code provisions. Héloïse et al. (2012) developed an empirical correlation which estimates amplification of soil as a function of site parameters which were obtained from KiK-net data set. By comparing the suggested soil amplification of European regulations, they recommended to improve significantly both the site characterization criteria and the associated amplification factors, for microzonation studies and modify building design codes. Pitilakis et al. (2013) proposed code-oriented elastic acceleration response spectra considering effect of soil based on a huge number of ground motion data set from 536 sites from Greece, Italy, Turkey, USA and Japan. Tsang et al. (2017) introduced an alternative design spectrum model which considers the soil resonance effect without computing the site response analysis of a particular site.
Kolkata, the present capital of state West Bengal, located on soft deep alluvial soil deposit (Shiuly and Narayan, 2012, Shiuly et al., 2014, Shiuly et al., 2015, Nath, 2016). Thus, due to propagation of seismic wave in the soil layers may amplify during earthquake. Therefore, the buildings which are designed according to IS-1893 (part 1):2016, may not perform their desired level. Further, most of the buildings in the city are Open Ground Storey (OGS). In the present study, the performance of a typical G+1, G+4, G+9 storied OGS buildings have been studied considering stiffness of infill wall (WI) and without considering stiffness of masonry infill wall (WOI) using available 144 numbers of site specific ground motions and IS-1893 (part 1): 2016 spectrum compatible ground motion due to both Design Basis Earthquake (DBE) and Maximum Considerable Earthquake (MCE). In order to obtain the response, Nonlinear Time History Analysis (NLTHA) has been performed using SAP 2000 Vs19 software. A variation of performance has been studied in different locations in the city.