Seismic Vulnerability of Highway Bridge Embankments

The objective of this study was to provide a simple methodology to conduct preliminary seismic vulnerability assessment of bridge embankments to identify and prioritize embankments susceptible to failure. A ranking model that provides a priority list of embankments with the highest seismic risk of failure is generated. A step-by-step methodology is presented to estimate the seismic slope stability capacity-demand ratio, displacement, and liquefaction potential of the bridge embankments. Three categories are presented to identify the failure risk of the embankments. The ranking model is useful for a quick assessment of the sensitivity of the effect of various site conditions, earthquake magnitudes, and site geometry on possible movement of the designated embankments. The methodology is applied to identify the seismic risk of 127 bridge embankments along I-24 in western Kentucky. The variables of the embankments are the geometry, material, type, and properties of underneath soil and the elevation of both the natural ground line and the upper level of bedrock. A priority list of the embankments with the highest risk of seismic failure is generated for I-24 bridge embankments in western Kentucky during designated seismic events. The priority list will enable decision makers to decide on either carrying out further detailed evaluation or considering other appropriate actions for the bridge embankments with the highest risk of seismic failure.