Analysis of the cyclic behaviour of shear connections in steel-concrete composite bridge due to moving loads

It is presented a numerical procedure able to analyse the structural behavior of steelconcrete composite beams subjected to moving loads, considering the actual cyclic nonlinear relationship between the shear force and the slip of the connectors. The procedure allows to determine the oscillograms of the slip and the shear force of each connector corresponding to the transit of an assigned loading pattern. Fatigue checks, based on the strain-life approach can be carried out using such a numerical tool. The procedure was used to study the cyclic behavior of the connection of a 40 m span simply supported bridge-type beam subjected to a severe loading model: fatigue model 1 (ENV 1991-3) with a heavy abnormal 15 axles vehicle (3600 kN). The results allowed to assess the damage accumulated in the connectors due to one thousand transits of the considered load. Significant damage occurs in the studs close to mid-span.