Seismic Design of Bridges in the New Madrid Seismic Zone 

Presented By: Timothy Huff, Tennessee Tech University
Description: The hazard characteristics of the Mississippi Embayment in the New Madrid seismic zone present multiple challenges to structural designers. Deep soil deposits in the embayment may render code-based site factors obsolete in some cases. The lack of strong motion recording in the region makes the development of ground motion models difficult. Nonetheless, the seismic hazard in the embayment is severe with design response spectra in some locations among the highest in the US. To satisfy current, no-collapse performance goals, bridge designers have employed seismic isolation, partial isolation, reduced resistance column base details, restrainers, and unidirectional joint restraints to meet these challenges. Presented here are relevant projects as well as future challenges as multi-level-seismic-hazard, performance-based seismic design appears to be on the horizon.