Weiwei Zhan

Weiwei Zhan

Assistant Professor at University of Central Florida

Site Response Nonlinearity Assessment

less than 1 minute read

Site response nonlinearity describes the change of site responses from weak to strong events, shedding light on nonlinear soil dynamic behaviors. I studied the site response nonlinearity at four liquefiable vertical array sites (with liquefaction surface manifestation during at least one earthquake; the site has at least two ground motion sensors, one at the surface and one at the depth). I processed thousands of ground motion waveforms and computed surface-to-borehole spectral ratios (frequency-wise site amplification curves). I used shape parameters to quantify site response nonlinearity and developed site-specific regression models to evaluate the site vulnerability to nonlinear site responses. I found that the liquefaction could enhance the amplification of low-frequency and very-high-frequency ground motions, and these liquefaction effects vary from site to site.


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