Stability of Bridge Piers Subjected to a Probable Flood Event Followed by a Probable Seismic Event

Abstract

Scour-induced reduction in bridge stability can develop vulnerabilities during a probable seismic event. This problem has been typically addressed by researchers as if these two extreme events have no joint probability of occurrence for a given range of time. This paper evaluates the stability of bridge piers subjected to various flood events followed by different seismic events with some known probability of occurrence. An analysis guideline is set for a probabilistic method to develop a matrix of analysis. In the case study, changes in structural response and stability of a bridge pier are identified using this probabilistic approach. Six different flood conditions evaluated under four different seismic events are analyzed to assess the structural stability. The low-level and high-probability flood events in combination with a moderate seismic event are determined to negatively affect the structural response. The reduction in structural stability is checked for column flexure, pile axial load, pile moment, and pile shear capacities.