Probabilistic seismic hazard zonation to investigate the effect of soil condition on earthquake acceleration propagation, Case study Hamadan City, Iran

The shear wave velocity (Vs) is a key factor in influencing ground motion intensity and amplifying seismic waves. The city of Hamedan, due to its geological position atop alluvial deposits, exhibits a wide variation in Vs values. This heterogeneity may result in considerable structural damage during major seismic events. This study, which aims to evaluate site-specific effects on ground motion, developed a shear wave velocity map using existing subsurface geotechnical investigations. A probabilistic approach was employed for seismic hazard assessment. The results show that lower-Vs zones exhibit elevated seismic accelerations. Disaggregation analysis identifies the Nahavand and Morvarid faults as major contributors to seismic hazard in Hamedan, particularly under long return periods. The influence of distant seismic sources is evident and should be considered in the seismic design process of tall buildings.