Special Earthquake Engineering Seminar
November 11, 2016
“Hazard-compatible stochastic ground motion modeling & Mitigating seismic risk in the developing world: lessons learned in Haiti and promotion of alternative residential-housing solutions”
Department of Civil and Environmental Engineering and Earth Sciences, Department of Aerospace and Mechanical Engineering,
University of Notre Dame
This seminar has two, distinct parts. The first part discusses the tuning of stochastic ground motion models to establish hazard compatibility. Stochastic ground motion models can
produce acceleration time-histories by modulating a white-noise sequence through functions that address spectral and temporal properties of the seismic excitation. This is established by relating the parameters of these functions to earthquake and site characteristics through predictive relationships, commonly established through a regression analysis that ultimately targets waveform match. For seismic risk assessment applications, it is important that the hazard resulting from the resultant stochastic ground motion model is compatible with the prescribed hazard at the site of interest, something that is not necessarily guaranteed through the aforementioned regression analysis. Here a computational efficient framework is discussed so that an existing stochastic ground motion model can be further tuned to match the prescribed hazard for a specific site and structure of interest.
The second part of the seminar moves into a different topic and discusses the challenges in mitigating risk in the developing world. On January 12, 2010 a devastating earthquake struck the Republic of Haiti. Despite measuring just a moderate 7.0 on the Richter scale, this earthquake is considered one of the most catastrophic natural disasters in recent history, exposing the vulnerabilities of established construction practices in a country plagued by poverty and political unrest. Close to seven years after the earthquake the sad reality is that most families displaced due to the earthquake do not have a clear road map toward permanent, earthquake resistant housing. This presentation shares the experience of our research team in Léogâne, Haiti, during the development of an empowerment framework for (a) assessing seismic vulnerabilities, (b) understanding the economic/cultural/societal origins of these vulnerabilities and (c) offering alternative solutions when operating in such unique, resource-constrained environments.