Newly developed site-specific response spectrum for site in Abbottabad city, Pakistan and its comparison with building code of Pakistan, 2021

Use of site-specific response spectrum has become an integral part of seismic hazard analysis to incorporate the effects of soil beneath the structure. Current study has been performed as a result of lesson learned from recent devasting Turkey earthquake of 6th February 2023, where design ground motions were greatly exceeded. This study presents development of site-specific response spectrum and its comparison with recently published building code of Pakistan, 2021. The results of this study indicate that mobilized shear strength of input motions increased along depth due to development of different shear strain in different soil layers which affected the shear modulus showing its resistance to deformation by exerted shear stress. Input bedrock motions with PGA of 0.31g amplified at the surface up to 0.36g as result of response from the soil profile used. After comparison with design spectrum of building code 2021, it is further validated that the development of site-specific response is underpinning when using design spectrum of BCP-2021 developed for return period of 475 years under currently used soil/site conditions.