Performance-Based Framework for Evaluating Truck Collision Risk for Bridge Piers

Abstract

A risk-based method implemented within a performance-based design framework is proposed for protecting bridge piers subject to truck impact. Monte Carlo simulations are performed to calculate the probability of damage exceedance of impacted piers based on demand-to-capacity ratios. The demand is computed from the base shear of the pier under a calibrated pulse loading, which represents impact by a single-unit truck or a tractor-semitrailer. Four different highway classes are considered in this study with different ratios of truck types in the traffic volume, including single-unit trucks and tractor-semitrailers. Based on the simulation results, the probabilities of exceedance for different damage levels of typical or critical bridges, given a collision event, are provided for each highway class as a function of the posted speed limit and shear capacity of the impacted pier. The proposed methodology is verified through high fidelity simulations of truck collision with a full-bridge model and formatted in a manner that facilitates its direct adoption into current specifications.