Presentation by Haizhong Zhang

Probability seismic hazard analysis based on Fourier amplitude spectrum - March 5, 11 a.m., room 116


Probability seismic hazard analysis based on Fourier amplitude spectrum



My presentation is structured into three parts: previous studies, current work, and research plans, with a primary focus on seismic hazard analysis. In previous studies, firstly, we concentrated on the challenge of reasonably incorporating the effects of local site conditions into the seismic hazard analysis. We systematically investigated site effects on response spectra based on random vibration theory as well as statistical analysis of seismic records and developed an efficient model for the response spectral ratio. Secondly, we addressed the issue of easily converting different ground-motion-intensity measures in the seismic hazard analysis. For this purpose, we explored the relationship between the response spectral acceleration, response spectral velocity, response spectral displacement as well as energy spectrum, based on random vibration theory as well as statistical analysis of seismic records. Consequently, we developed conventional models to facilitate the conversion between these diverse spectra. At present, our focus lies in the simultaneous derivation of various ground-motion-intensity measures—such as response spectral acceleration, velocity, displacement, and energy spectrum—through a single conduction probability seismic hazard analysis. To achieve this, we utilize the Fourier amplitude spectrum model in place of the ground motion prediction equation for each intensity measure. This choice is driven by the ease and strict convertibility of the Fourier amplitude spectrum to each spectrum. However, with the adoption of this innovative approach, we encounter a challenge in evaluating the annual intensity exceedance probability, commonly known as the hazard curve. While we initially explored the moment method, we recognize its complexity, particularly for earthquake engineers. Thus, there is a pressing need in our ongoing research to identify a more easily understood method for obtaining the hazard curve, ensuring accessibility and clarity in our analyses.



Dr. Haizhong Zhang has been an Associate Professor at Yamagata University of Japan, since 2023. He is also a part-time Associate Professor at Iwate University of Japan. He earned his doctoral degree from Kanagawa University of Japan in 2018. From 2018 to 2023 Dr. Haizhong Zhang worked as an Assistant Professor at the Department of Architecture at Kanagawa University. He is a Member of AIJ, JGS, JAEE, and JSCE. His research is mainly about seismic hazard analysis, site effects, transformation between different ground-motion-intensity measures, and damping modification factors of response spectra. His research achievements have been published in 20 academic journals.


Additional information

The presentation session will take place in the institutes library, room 116, on Thursday, March 5, 2024. Start is at 11 a.m. The presentation will also be available via Webex online meeting. If you want to participate online please contact Torsten Ilsemann.