Title:
Experimental Testing and Refined Load Rating of Concrete Slab Bridge
Author(s):
N. H. Kabir, T. Terzioglu, M. D. Hueste, S. Hurlebaus, J. B. Mander, and S. G. Paal
Publication:
Structural Journal
Volume:
123
Issue:
4
Appears on pages(s):
3-16
Keywords:
concrete slab bridge; equivalent slab width; finite element analysis; load rating; load testing; slab bridges with integral curbs
DOI:
10.14359/51749550
Date:
7/1/2026
Abstract:
The aging reserve of bridges in the United States needs load-rating assessments to ensure sufficient load-carrying capacity and safety. Bridges without sufficient capacity to carry the legal loads are load-posted. These load limits reroute traffic, which may result in traffic congestion and longer routes, and, thus impose inconvenience on travelers and significant costs to society. This paper investigates the potential for improvement in the load-rating process for simple-span concrete slab bridges. Such bridges are load-rated by the Texas Department of Transportation using simplified load-rating procedures, which are intended to be conservative and can have varying degrees of accuracy compared to the actual behavior of bridges. Finite element modeling was conducted to simulate the expected behavior of a representative concrete slab bridge, and the model was calibrated using experimental test data. The equivalent width results were compared with estimates from established design specifications and empirical guidelines. The methods developed for concrete slab bridges with integral curbs provided accurate estimates of moment demand for curb sections. In addition, an established analytical approach in the literature accurately predicted the moment demand for interior slab sections under one-lane loading, while the equations in current design specifications performed well for two-lane loading cases.
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