Monday, April 15, 2013
Special Mechanical and Civil Engineering Seminar
Earthquake Engineering Systems: Where it all Begins
Ting Lin, Postdoctoral Fellow , Department of Civil and Environmental Engineering, Stanford University
Science is curiosity driven; engineering, solution seeking; policy, action oriented. Earthquake engineering systems connect the complexity of science to the practicality of engineering and policy. This seminar will present recent progress in hazard-consistent ground motion selection methodology, ongoing efforts in performance-based earthquake engineering of systems, and a vision for multi-hazard sustainability.
Ground motion input is the bridge between seismic hazard and structural response, the first two elements of performance-based earthquake engineering. The Conditional Spectrum is used as a target response spectrum to select ground motions. To ensure hazard consistency, the computation of the Conditional Spectrum is refined by incorporating multiple causal earthquakes and ground motion prediction models. Ground motions are then selected from a database to match the target spectrum mean and variability, in order to assess system performance. Seismic evaluation of systems can benefit tremendously from advancements in structural modeling, seismic hazard characterization, and high performance computing, utilizing both recorded and simulated ground motions. This ground motion study has contributed to computational features in the US Geological Survey hazard mapping tools, and recommendations for building codes and guidelines.
The framework of earthquake engineering systems can be extended to multi-hazard risk assessments for the natural and built environments, taking into consideration the additional challenges from climate change. Current research includes multi-hazard contribution to dam failure and Probabilistic Sea-Level Rise Hazard Analysis, a novel framework that accounts for aleatory uncertainties from emission scenarios and epistemic uncertainties from prediction models. Through the science of hazard analysis, engineering of performance evaluation, and policy of planning and response, multi-hazard sustainability can be achieved.