Numerical investigation of the parameters influencing site effects

One of the most important topics in geotechnical earthquake engineering is the examination of site effects. This phenomenon alters the characteristics of seismic waves, leading to amplified vibrations and consequently increasing financial and human losses. Today, various methods exist for assessing site effects, among which numerical methods are among the most widely used due to their reasonable costs, reduced time, and high accuracy. In this research, a problem was subjected to the effects of three different earthquakes (Bam, Naghan, and Tabas). By comparing the results of each earthquake, the site effects were identified in terms of changes in peak gorund acceleration (PGA), frequency content, and shaking duration. Additionally, to investigate the effects of soil layering, the position of the layers was altered, revealing significant impacts of layer changes on seismic wave characteristics. Finally, to assess the effect of earthquake source type, one earthquake was evaluated at two different stations (near/far field). Results indicated a significant influence of the epicentral distance on the amplification and attenuation of waves.