Supplementing VS30 with H/V Spectral Ratios for Predicting Site Effects

Research Article| September 25, 2017 Supplementing VS30 with H/V Spectral Ratios for Predicting Site Effects Dong Youp Kwak; Dong Youp Kwak aGeotechnical Modeler, RMS, Inc., 7575 Gateway Boulevard, Newark, California 94560eFormerly at University of California, Los Angeles (UCLA), 5731 Boelter Hall, Los Angeles, California 90095‐1593. Search for other works by this author on: GSW Google Scholar Jonathan P. Stewart; Jonathan P. Stewart bDepartment of Civil and Environmental Engineering, University of California, 5731 Boelter Hall, Los Angeles, California 90095‐1593 Search for other works by this author on: GSW Google Scholar Saeed‐ullah J. Mandokhail; Saeed‐ullah J. Mandokhail cDepartment of Civil and Environmental Engineering, Hanyang University, 504 Jaesung Civil Engineering Building, Seoul 133‐791, South Korea Search for other works by this author on: GSW Google Scholar Duhee Park Duhee Park dDepartment of Civil and Environmental Engineering, Hanyang University, 506 Jaesung Civil Engineering Building, Seoul 133‐791, South Korea, dpark@hanyang.ac.kr Search for other works by this author on: GSW Google Scholar Author and Article Information Dong Youp Kwak aGeotechnical Modeler, RMS, Inc., 7575 Gateway Boulevard, Newark, California 94560eFormerly at University of California, Los Angeles (UCLA), 5731 Boelter Hall, Los Angeles, California 90095‐1593. Jonathan P. Stewart bDepartment of Civil and Environmental Engineering, University of California, 5731 Boelter Hall, Los Angeles, California 90095‐1593 Saeed‐ullah J. Mandokhail cDepartment of Civil and Environmental Engineering, Hanyang University, 504 Jaesung Civil Engineering Building, Seoul 133‐791, South Korea Duhee Park dDepartment of Civil and Environmental Engineering, Hanyang University, 506 Jaesung Civil Engineering Building, Seoul 133‐791, South Korea, dpark@hanyang.ac.kr Publisher: Seismological Society of America First Online: 27 Sep 2017 Online Issn: 1943-3573 Print Issn: 0037-1106 Bulletin of the Seismological Society of America (2017) 107 (5): 2028–2042. https://doi.org/10.1785/0120160353 Article history First Online: 27 Sep 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Dong Youp Kwak, Jonathan P. Stewart, Saeed‐ullah J. Mandokhail, Duhee Park; Supplementing VS30 with H/V Spectral Ratios for Predicting Site Effects. Bulletin of the Seismological Society of America 2017;; 107 (5): 2028–2042. doi: https://doi.org/10.1785/0120160353 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract Site amplification models using relatively simple site proxies (e.g., averaged shear‐wave velocity and soil depth) do not capture site‐specific resonance effects observed at soil sites having a high shear‐wave velocity impedance contrast. We present a model to supplement ergodic site amplification equations to consider these effects (i.e., our model is additive to ergodic equations in a natural log sense). The model is conditional on properties of horizontal‐to‐vertical (H/V) spectral ratios recorded at the site of interest and consists of a frequency‐domain pulse function parameterized by site period, pulse amplitude, and pulse width. H/V spectral ratio peaks are observed in 97% of sites in our data set. When no appreciable H/V spectral ratio peak is present, we provide a broadband adjustment to the ergodic model. Because H/V spectral ratios are typically measured under small‐strain (effectively viscoelastic) conditions but applied in engineering practice for stronger shaking conditions, our model modifies site period for nonlinear site‐response effects. The model adapts in an empirical manner H/V spectral ratio attributes measured from Fourier amplitude spectral ratios to horizontal response spectral amplification using a data set from Japan composed of sites having sufficient recordings to produce stable mean H/V spectral ratios. Compared to an ergodic model that does not consider H/V spectral ratios, application of the proposed model reduces natural log within‐event standard deviation by an average of 0.04. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.