Effect of Dog-Legged Staircase on the Seismic Response of Hill Buildings

RC framed buildings on hill slopes possess different structural performance than on the level terrain. The unsymmetrical structure of these buildings imparts additional forces and moments when subjected to seismic loads. Previous studies concluded that dog-legged staircase elements impart lateral stiffness to the building structure and work as efficient energy dissipators under earthquake loads. Also, the position of the staircase structures plays significant role in the modal response of the building. Thus, in the present study, the influence of dog-legged type staircase on the seismic performance of two hill building configurations has been explored. Both stepback and setback-stepback configurations have been modelled with and without staircase structural elements. The three-dimensional models have been analysed using Equivalent Static and Response Spectrum methods and the dynamic parameters so obtained are presented in terms of total base shear, fundamental time period, storey drift and shear forces induced in the columns at foundation level in buildings, and compared within the considered configurations.