Shear connection in composite beams incorporating open-trough profile decks

Abstract

For composite steel-concrete beams, it is well known from tests that the shear capacity of welded-stud connectors can be reduced by the presence of profiled steel sheeting if it has an open-trough profile where the open-trough ribs, usually trapezoidal in shape, are laid transverse to the steel beam. Rib shearing failures with open-trough profile decks can be prevented using special waveform reinforcement. Rib punch-through is another possible mode of failure which is also brittle in nature. For this mode, a new, patented, low-cost small-scale component has been developed that, when used in conjunction with each stud connector, can significantly increase the strength and ductility of the shear connection resulting in improved values of the reduction factor kt, in some cases the connection achieving the full capacity of connectors in a solid slab. An extensive series of tests is currently being undertaken to design the component, which takes the form of a steel ring positioned about the stud base, for a wide range of deck parameters and stud configurations. Rib shearing and rib punch-through failures can cause major problems with the shear connection of composite beams incorporating open-trough profile decks layed transverse to the steel beam. Novel methods for overcoming the effects of these failure modes are under development and are briefly described in the chapter. These advances are being immediately put into practice in Australia where open-trough profile decks are now beginning to be used.