Effects of Corrosion and Vehicular Impact Damage on Ultimate Capacity of Steel Bridge Beams

Abstract

Steel bridge beams with corrosion and vehicular impact damage were modeled with finite element analysis. Advanced software was used to investigate buckling capacity, flexural stress distributions in beams with web holes, capacity of beams deformed by impact, and flexural stresses in remaining bridge beams with one beam removed. Computer-generated stress distributions were compared to hand-calculated distributions. Flange thinning and buckling capacity reduction are directly related. Web holes have no significant impact on buckling, but decrease ultimate moment capacity. The magnitude and location of maximum flexural stress depends on various geometric parameters, and will either be predicted by elastic beam theory or the Vierendeel method. Impact damage can cause significant reductions in yielding and post-buckling capacities. Preliminary tests show that it may be possible to remove one of four main bridge beams from service while allowing one lane of traffic on the bridge without dangerously elevating flexural stresses.