Published: 
By  Sensing and Evaluation Laboratory (I-S2EE)

Congratulations to Amir Gheitasi (Research Associate) in my research group for getting our paper accepted for the Transportation Research Record. The title of the paper is “Implications of Overload Distribution Behavior on Load Rating Practices in Steel Stringer Bridges”. This paper highlight the influence of the evolution of load distribution response on the load ratings of typical steel girder bridges.
Abstract:
With the ever-increasing demands for transporting goods and services, transportation officials are facing a growing challenge with the safety of in-service bridges under the passage of over-sized and/or over-weight vehicles. Current load rating practices provide the basis for evaluating the operational safety of the in-service structures using engineering judgments and simplifying assumptions. However, a true measure of the system performance under the impact of irregular loading scenarios requires knowledge of different aspects of the system-level characteristics including the lateral load distribution behavior. In this study, non-linear FE analysis has been implemented to evaluate the evolution of load distributing mechanism in two representative in-service structures in the state of Michigan subjected to overloads. In addition, rating factors were defined for the selected structures based on the LRFR methodology. Results from this study demonstrate that current design and rating practices are overly conservative in predicting the actual distribution behavior and assessing the safety of the in-service structures under the effect of irregular loading conditions. This investigation also highlights the importance of implementing a refined method of analysis which can help bridge engineers to support their permit and posting decisions.