Ground motion selection for analysis of near-fault civil structures using broadband physics-basedearthquake simulationsperiod of performance: 8/1/2022 through 7/31/2023NONLINEAR analysis of civil…

Ground motion selection for analysis of near-fault civil structures using broadband physics-basedearthquake simulationsperiod of performance: 8/1/2022 through 7/31/2023NONLINEAR analysis of civil structures subjected to earthquake ground motions is a critical part of performance assessment of existing structures, and performance-based design of new structures. Proper selection of earthquake records for a particular design or assessment study is a key component of nonlinear structural response analysis. Because of the sparsity of recorded earthquake ground motions at locations close to active faults, the characteristics of these motions are difficult to understand and systematically account for, and ground motion prediction models contain significant uncertainties for large earthquakes at short distances. Consequently, little guidance is currently available on the appropriate selection of earthquake records for performance assessment of structures near active faults. Among the challenges that preclude the development and evaluation of such selection procedures are: (1) poor understanding of the likelihood and properties of strong ground velocity pulses in near-fault ground motions, and their impacts on structures, (2) difficulty quantifying the likelihood and impacts of ground displacement pulses on near-fault structures, and (3) lack of understanding of the interaction between site conditions and fault rupture directivity effects at short distances. The purpose of this project is to address the aforementioned challenges through analysis of physics-based broadband earthquake fault rupture simulations, and their impacts on modern building structures. The project will integrate earthquake and structural simulations to achieve the following: (1) identify the characteristics of near-fault shaking that are most important in producing high demands on structures, (2) quantify the impacts of the different near-fault ground motion characteristics on the response of modern low-, mid- and high-rise reinforced concrete buildings of various dynamic properties, and (3) develop statistical models and generate a set of guidelines for selection of earthquake records which appropriately represent the risks expected for structures located in urban areas near earthquake faults. The project activities include analysis of a large suite of simulated earthquake ground motion records, assessment of the sensitivity of the response of archetypical buildings to near-fault ground shaking, and development of near-fault earthquake record selection model and guidelines. A technical report will be produced to summarize the guidance and best-practice criteria for selecting earthquake records for engineering risk assessment of near-fault structures. In addition, the findings of this project will complement the existing probabilistic seismic hazard analysis procedures and the U.S. Geological survey hazard tools, and facilitate wider-scale use of simulated earthquake ground motions in engineering assessments. The project is intended to benefit both practicing engineers and the earthquake research community at the interface of seismology and structural engineering.