Study On The Bending Rigidity Of Profiled Steel Sheeting-Concrete Composite Slabs

Profiled steel sheeting-concrete composite slab has been extensively applied to engineering recently because of its ease of construction, good ductility and economic returns, etc. The shear-bond behavior between profiled steel sheeting and concrete is the basis of their cooperation, and would have great effects on failure mode, bearing capacity, rigidity and deformation design theory of composite slabs. The engineering designers have taken into account this factor more and more at present and we have got lots of research results on longitudinal shear capacity of composite slab, but for its deformation performance studies have relatively backward. The current design method of composite slabs ignores the slip effect between profiled steel sheeting and concrete. Therefore, the deflection obtained by this method is relatively low and the structure may be on the unsafe side.In this paper, composite slabs of YX75-200-600 type and YX76-344-688 type were studied. By analyzing the test results and the bearing performance of these specimens, the stress characteristics of three stages during the loading, the variation of central axis and the variation regularity of the load-deflection curves, the load-slip curves, the load-strain curves of profiled steel sheeting and concrete were obtained. Then the influence of the studs, the deck shape and thickness of profiled steel sheeting and the shear span of these specimens on the rigidity of composite slabs were analyzed too. All of these conclusions provide test foundation for theoretical analysis and engineering application of these type composite slabs.Based on the basic assumption and elastic theory, the flexure differential equation of composite slabs under uniform is deduced, and the deflection formula under various load form is obtained in which the slip effect is taken into account. Then the article presents the reduction factor of rigidity and analyses the influential rules about the design parameters on it. Finally compare to the test results of the composite slabs with profiled steel sheeting, and the comparison show that the value of deflection calculated is consistent with that of tests, and their average value of ratio is 0.97.