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Comparison of measurement- and proxy-based Vs30 values in California

Alan K. Yong
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Abstract

This study was prompted by the recent availability of a significant amount of openly accessible measured V S 30 values and the desire to investigate the trend of using proxy-based models to predict V S 30 in the absence of measurements. Comparisons between measured and model-based values were performed. The measured data included 503 V S 30 values collected from various projects for 482 seismographic station sites in California. Six proxy-based models—employing geologic mapping, topographic slope, and terrain classification—were also considered. Included was a new terrain class model based on the Yong et al. (2012) approach but recalibrated with updated measured V S 30 values. Using the measured V S 30 data as the metric for performance, the predictive capabilities of the six models were determined to be statistically indistinguishable. This study also found three models that tend to underpredict V S 30 at lower velocities (NEHRP Site Classes D–E) and overpredict at higher velocities (Site Classes B–C).

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Alan K. Yong. 2016-02-01. Comparison of measurement- and proxy-based Vs30 values in California. https://doi.org/10.1193/013114eqs025m

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