The impact of a PEER funded research project "Validation and Utilization of Physics-based Simulated Ground Motions for Bridge Performance Assessment" is highlighted below. The project Principal Investigator (PI) is Farzin Zareian, Associate Professor, UC Irvine. The Research Team includes Mayssa Dabaghi, Co-PI, American University of Beirut, Jawad Fayaz, Graduate Student Researcher, UC Irvine, and Sarah Azar, Graduate Student Researcher, American University of Beirut.
The mainstream approach for designing and assessing structures to withstand impacts of seismic hazard is to utilize a set of selected and modified ground motions from past global recordings of seismic events. Such an approach does not allow the opportunity to embrace the advancements in ground motion simulation, resulting in waveforms tailored for the structures' location. A validated ground motion simulation method opens significant research opportunities to investigate seismic events' regional impact on essential components of distributed systems (e.g., highway bridges in a transportation system). The main hurdle in using simulated motions is the lack of consensus on the acceptable accuracy of the computed structural responses. Validation methods for simulated ground motions can be categorized into three main types. Type I validation methods are based on historic events; they show if ground motion waveforms obtained from replicating a single event at their respective recording stations have the same central value of response as their corresponding recordings. Type II validation methods focus on the similarity of trends in important parameters representing ground motion characteristics (e.g., peak ground acceleration, building response) with event and site parameters obtained from simulations and recordings. In contrast with Type I validation, Type II validation may utilize a population of past events to form the trends in ground motion parameters. Type III validation methods find the equivalency between simulated and recorded ground motions using established structural/earthquake engineering principles and statistical tools; similarity of response spectra is the cornerstone of such equivalency checks. The methodology presented in this research is of the Type II validation approach. The suggested validation methodology's main contribution resides in its ability to be tailored for the target simulation method and engineering application while founded on a set of established engineering principles and statistical tools.