EXPERIMENTAL STUDY ON PLASTIC HINGE AND INTERNAL FORCE REDISTRIBUTION OF CONTINUOUS STEEL-CONCRETE COMPOSITE BEAMS WITH WEB OPENINGS

In order to investigate the mechanical performance of continuous steel-concrete composite beams with web openings, five continuous composite beams with web openings and a continuous composite beam without web openings were tested. The behavior of plastic hinges and internal force redistribution were studied emphatically. The test results show that web openings decrease the stiffness and the ultimate load-carrying capacity. The plane hypothesis is not satisfied for section in the web opening area. The failure process of the five continuous composite beams shows that a shear force plastic hinge first formed and ultimately a kinematical mechanism generated in the region of the web opening. The continuous composite beams with web openings have already shown redistribution phenomenon when compared with the composite beams without web openings in elastic stage. In addition, the results reveal not only moment redistribution but also shear force redistribution between the concrete and steel components for continuous composite beams with web openings.