Experimental study and numerical simulation on shear behavior of steel and concrete composite beam with molybdenum tailing

To improve the flexural performance of steel-concrete composite beams and alleviate the problem of sand depletion caused by the application of concrete structures, this paper proposes a new type of steel-molybdenum tailings concrete composite beam. In order to further study the shear performance of the new type of steel-molybdenum tailings concrete composite beam, this paper couples molybdenum tailings replacement ratio (0%, 50%, and 100%) and shear span ratio (1 and 2) as research parameters, designs a total of six 1:2 scaled composite beam models, and conducts monotonic loading tests to study the failure process, failure mode, ultimate bearing capacity, deformation, and local strain of some typical measuring points of the new composite beam. The steel and concrete composite beam with the molybdenum tailing has the similar mechanical behavior for each ratio of the shear span to the effective depth with that of the steel and concrete composite beam. In addition, they have a little difference in the failure processes for each ratio of the shear span to the effective depth, whereas they show typical diagonal compression failure mode for the ratio of the shear span to the effective depth is equal to 1 and the representative shear-compression failure mode for the ratio of shear span to effective depth is 2, and have no obvious difference in failure mode for each ratio of the shear span to the effective depth. Their shear resistance mechanism is basically the same. Furthermore, based on the validated finite element model, this paper conducted a parameter extension analysis. The finite element results show that: The ultimate load bearing capacity of the steel and concrete composite beam with molybdenum tailing varies significantly with the beam section size (beam section width and beam depth), reinforcement ratio, and the ratio of the shear span to the effective depth; Whereas it has little relation to the steel plate thickness. This provides the necessity and feasibility to use the steel and concrete composite beam with the molybdenum tailing in engineering practice. The proposed equation in this study is based on the previous researches and the simulated and test results. The proposed equation is rigorous and thorough and the predicted results are highly accurate and effective.