Using Eurocodes and Aashto for assessing shear in slab bridges

Reinforced concrete short-span solid-slab bridges are used to compare Dutch and North American practices. As an assessment of existing solid-slab bridges in the Netherlands showed that the shear capacity is often governing, this paper provides a comparison between Aashto (American Association of State Highway and Transportation Officials) practice and a method based on the Eurocodes, and recommendations from experimental research for the shear capacity of slab bridges under live loads. The results from recent slab shear experiments conducted at Delft University of Technology indicate that slabs benefit from transverse force redistribution. For ten selected cases of straight solid-slab bridges, unity checks (the ratio between the design value of the applied shear force and the design beam shear resistance) are calculated according to the Eurocode-based method and the Aashto method. The results show similar design shear forces but higher shear resistances in the North American practice, which is not surprising as the associated reliability index for Aashto is lower.