National Review on Use and Performance of Uncoated Weathering Steel Highway Bridges

Abstract

Uncoated weathering steel (UWS) bridges have been in use in the United States for nearly 50 years, now enabling the long-term performance of these structures to be assessed. This was accomplished by surveying the varied experiences of 52 U.S. transportation agencies, along with data analysis on all UWS bridges known within these and other agencies, which total nearly 10,000 structures. Climate and age were key considerations in this data analysis. Contrary to previous, more limited research, this analysis showed that there is not a strong trend in UWS bridge performance as a function of climate. A similar climate analysis for non-UWS bridges also showed a counterintuitive relationship between some climate types and these bridges. This suggests that design and maintenance practices may be more influential to UWS performance than climate, and further research to cultivate current best practices in this regard is recommended. Comparison between the UWS and non-UWS data sets also reveals that UWS bridges generally perform well in relation to non-UWS bridges.