New intensity prediction equation in Western China considering site equivalent shear wave velocity

Abstract

Intensity prediction equations (IPEs) are critical for quickly obtaining the macroscopic intensity of a site post-earthquake, with regional dependencies influencing their design. Historically, most IPEs in China have focused primarily on the factors of distance and magnitude. This study develops site-specific IPEs for Western China, using data from 53 seismic events since 1970, to address the previously overlooked importance of site conditions and overcome the limitations of past models. The data were categorized into three site groups, with IPEs derived through multiple nonlinear regression methods. Our findings reveal that macroscopic intensities at category III and IV sites are notably higher than those at categories I and II, with this disparity increasing alongside the magnitude. Unlike conventional IPEs, the IPEs proposed in this paper incorporate local geological and seismological characteristics, enhancing prediction accuracy across varied site conditions. This methodology distinctly contrasts with prior approaches by providing a nuanced assessment that integrates comprehensive site categorization, resulting in more precise intensity predictions. This advancement is particularly crucial for effective emergency management and disaster mitigation strategies in seismically active regions.