The recent steep increase in seismicity rates in Oklahoma, southern Kansas, and other parts of the central U.S. led the U.S. Geological Survey (USGS) to develop, for the first time, a probabilistic seismic hazard forecast for one year (2016) that incorporates induced seismicity. In this study, we explore a process to ground-truth the hazard model by comparing it with two databases of observations: Modified Mercalli Intensity (MMI) data from the “Did you feel it?” (DYFI?) system, and peak ground acceleration (PGA) values from instrumental data. As the 2016 hazard model was heavily based on earthquake catalogs from 2014-2015, this initial comparison utilized observations from these years. Annualized exceedance rates were calculated with the DYFI? and instrumental data for direct comparison to the model. These comparisons required assessment of the options for converting hazard model results and instrumental data from PGA to MMI for comparison with the DYFI? data. In addition, to account for known differences that affect the comparisons, the instrumental (PGA) and DYFI? data were declustered, and the hazard model adjusted for local site conditions. With these adjustments, examples at sites with the most data show reasonable agreement in the exceedance rates. However, the comparisons were complicated by the spatial and temporal completeness of the instrumental and DYFI? observations. Furthermore, most of the DYFI? responses are in the MMI II-IV range, whereas the hazard model is oriented toward forecasts at higher ground motion intensities, usually above about MMI IV. Nevertheless, the study demonstrates some of the issues that arise in making these comparisons, thereby informing future efforts to groundtruth and improve hazard modeling for induced seismicity applications.
Congratulations to Isabel on a nice paper! Check out the details here.
Update (as of 12/7/17): this paper is now available online at the journal's website!
Orlando Arroyo has joined the faculty as an Assistant Professor at Universidad de la Sabana, near Bogota Colombia.
Cody Harrington is working in the Truckee office of Gabbart and Woods.
Travis Marcilla is designing modern homes at phStructure.
Congratulations guys! We'll miss you!
Congratulations to Orlando Arroyo, whose paper "Evaluating the Performance of Topologically Optimal RC Moment Frame Buildings using a PBEE Framework" has been accepted by the Journal of Earthquake Engineering. The paper will be available here shortly.
Congratulations are also in order to Juan Olarte and Balaji Paramasivam, whose paper "Centrifuge modeling of Mitigation-soil-foundation-structure interaction on liquefiable ground" has been accepted by the Soil Dynamics and Earthquake Engineering. This paper will also be available here shortly.
Finally, Erin Arneson and Derya Deniz's paper "Information Deficits and Post-Disaster Recovery" will shortly be published by ASCE's Natural Hards Review. Good work Erin and Derya!
Cody Harrington successfully defended his thesis ADVANCEMENT OF PERFORMANCE-BASED EARTHQUAKE ENGINEERING FOR RC FRAME BUILDINGS: APPLICATION TO RETROFIT DESIGN AND CONSIDERATION OF VERTICAL GROUND MOTIONS on Nov. 15.
Orlando Arroyo defended his thesis at Pontificia Universidad Catolica de Chile on "OPTIMIZACIÓN DEL DISEÑO DE UN EDIFICIO DE PÓRTICOS DE HORMIGÓN ARMADO PARA MINIMIZAR EL DRIFT"
Our paper on this topic is forthcoming in the ACI Structural Journal, co-authored with Curt Haselton, Greg Deierlein and Sarah Taylor-Lange. This paper represents an update version of the relationships in a 2007 PEER Report.
PhD students Sarah Welsh-Huggins is presenting her work at the 5th International Symposium on Life-Cycle Civil Engineering - IALCCE 2016 - in Delft, the Netherlands this week. Her paper is entitled "Is a Stronger Building also Greener? Influence of Seismic Design Decisions on Building Life-Cycle Economic and Environmental Impacts".
A paper coauthored with Derya Deniz (former postdoc), Erin Arneson, Shideh Dashti and Amy Javernick-Will will appear in Natural Hazards and has been published online. We explored the losses experienced in the City of Boulder in the 2013 Floods.