SHEAR CONNECTION IN COMPOSITE BEAMS INCORPORATING PROFILED STEEL WITH NARROW OPEN OR CLOSED STEEL RIBS

The paper discusses a series of tests conducted to examine the influence of the narrow open steel rib on the performance of the shear connection in composite beams with the profiled steel sheeting ribs laid perpendicular to the beams. The test results showed that the minimum transverse spacing had to be increased to 80 mm for the shear connection to behave in a similar manner to that in a solid slab providing the distance of the studs from the ribs was greater than 60 mm. The objectives were to prevent the occurrence of a brittle rib-shearing failure and to ensure that straight reinforcing bars placed transverse to the steel beam are effective as longitudinal shear reinforcement. Exceeding this limit means that additional waveform reinforcement is necessary to cross the horizontal shear surface passing at the level of the tops of the ribs that can form in the region between the shear connectors. New design rules that account for all these factors have recently been introduced into Australian Standard AS 2327.1, or are being considered for inclusion and are described in this paper.