ABSTRACT
Damage to highway steel bridge members may occur when an excessively high, over-sized truck dynamically impacts a bridge. The collision could result in significant plastic deformations in localized areas of the steel girders. The research team investigated the effect of heat straightening on the behavior of impacted highway steel bridge girders. An extensive list of highway structures in the state of West Virginia, which have been struck and damaged by over-height vehicles, has been developed. Detailed conditions of each struck bridge and times of damage/heat-straightening repairs are documented. Current West Virginia Department of Transportation (WVDOT) process for recording data in damage inspection reports of struck and misaligned member is reviewed and reported. WVDOT decision-making process for whether, or not, to repair damaged members is based on evaluating the remaining load-carrying capacity of the damaged members combined with viewpoints of district engineers and the agency consultants. The research team demonstrated how to determine if the damaged girder should be repaired to its original condition, or if it has sufficient remaining moment capacity to safely resist the expected load in its distorted condition. Flowcharts for assessing members’ structural damage and designing of a retrofit process following FHWA guide for heat straightening of damaged steel bridge members are developed. Important recommendations and precautions for heat-straightening repairs are established taking into account recommendations from FHWA “Guide for Heat-Straightening of Damaged Steel Bridge Members,” NCHRP Report 604, as well as other research reports and references from a comprehensive literature review that was completed during the first phase of the study.
