Cracking of reinforced concrete deck on skewed bridges

Many highway bridge decks are made of reinforced concrete for a number of advantages. On the other hand, concrete materials are susceptible to cracking, which may expedite deterioration. This paper focuses on the behavior of skewed concrete bridge decks on steel superstructure subjected to thermal load and truck load. It was to meet the need of the Michigan Department of Transportation for investigating observed skewed deck cracking. Full scale bridge deck measurement and finite element analysis were performed. The numerical modeling was verified using the in-situ deck strain measurement of the bridge skewed at 49.10. The results show that service truck loads induce low strains / stresses in the deck, unlikely to initiate concrete cracking alone. Rather the thermal load and shrinkage of cement caused the observed cracking, due to the constraint of the supporting beams. Nevertheless, repeated truck load application may cause the cracks to become wider, longer, and more visible. In addition, the skew angle increases, not very significantly, the total strain/stress effect due to the truck wheel load.