Shear resistance of concrete bridge decks in tension

In concrete slabs of composite structures tension forces may occur, exceeding the tension forces in reinforced or prestressed structures. Deck slabs of composite bridges are often completely cracked, even under service loading. Those cracks have to transmit the shear forces induced by concentrated loads such as wheel loads. Laboratory experiments have been carried out by the Institute of Structural Design at the University of Stuttgart, to thoroughly study the shear resistance of composite slabs cracked by tension stresses. A numerical model on the basis of the finite element method has been verified by the test results and used to investigate the influence of different parameters on the shear strength. A new concept has been developed modelling the shear failure mechanism of slabs in tension. The results yielded a design equation rendering realistic values for the shear capacity of reinforced concrete slabs in tension.