Civil Engineering Association

Evaluation and Implementation of an Improved Methodology for Earthquake Ground Response Analysis: Uniform Treatment of Uncertainties in Source, Path and Site Effects

Caltrans geotechnical engineers initiated a research project aimed at broadening their perspective from simple geotechnical site response analyses to a more comprehensive seismological approach. The project was centered on a series of seminars on seismological theory and analyses using a pair of stochastic numerical ground motion models that allowed uniform treatment of uncertainties in recognized earthquake source, path, and site effects. The project was not intended to produce a “report,” but seminar notes and a portion of the analyses have been scanned and compiled for archival and educational value. Seven sets of seminar notes and two application examples are presented. Two seminars provide an overview of site specific specification of ground motion from a seismological perspective. Another seminar provides background on seismological instrumentation and processing of strong-motion recordings. A pair of seminars addresses empirical attenuation models and outlines the variety of numerical ground motion modeling approaches. The final pair of seminars systematically explore source, path and site effects on ground motion and various strategies employed to capture these effects for purposes of prediction. The two application examples use the stochastic model to explore the impacts and uncertainties of geotechnical site effects within the context of the broader seismological problem.