Crack width of reinforced concrete slab in the steel and concrete composite girders at negative moment region

In negative moment regions of continuous steel and concrete composite girders transverse cracks of reinforced concrete deck easely develop by tensile forces caused by service loads and shrinkage of concrete. Since these cracks reduce the durability of bridge decks, practical crack width should be controlled less than allowable value in design step. Although crack width is affected by steel stress, bar diameter, bar spacing, etc, the current Korean highway design code provides only one value of 1.5 percent for reinforcement ratio of the concrete area. In this paper, previous negative flexural test results are reviewed and crack width and crack spacing of five composite girders are compared with estimation value by Eurocodes. Based on the test results in Youn et al. (2006), the suitability of the current Korean highway design code and Eurocodes for the crack width evaluation of steel-concrete composite bridge deck is discussed.