Study On Punching Shear Performance Of Reinforced Concrete Slabs

In the course of popularizing and application of the concrete flat plate, the characteristic of the concrete slab has attended by people. It will fail in punching shear as unreasonable design. Because of the complicated failure mechanism the punching shear design hasn't solved absolutely. So it is necessary to take care of the punching shear research. Based on the existing work, theory and finite research have done to analyse the concrete slab's punching shear performance.First, Introduced the conception about the punching shear and difference with other failure. Summarized the influence factor of the punching shear capacity. Such as: Load area and shape, strength of concrete, composition of concrete, depth of slab, load position ratio of reinforcement, punching shear reinforcement and scale effect. Ratio of reinforcement and position of punching shear reinforcement determine the failure mode of axisymmetric slab. Load position is main influence factor for non-axisymmetric slab's failure mode.Second, Analysed the influence of bending reinforcement for the punching shear capacity and failure mode. Dowel action of the reinforcement in the plastic area provide the punching capacity. Its tensile stress can not provide the punching capacity for it hasn't work.Obtained the flexural capacity equation by yield line theory. Punching shear capacity equation gained combined the concrete's Ottosen four parameter failure criterion and reinforcement's dowel action. Generalized the distinguish method about the failure mode for the slab.At last, Analysed several kinds of concrete slabs by finite element program ANSYS. Derived the punching shear strength, crack mode, crack position and developing condition. They are anastomotic compared with experiment. It is feasible to simulate concrete slab's punching shear performance by finite element analysis.In this paper, some research have done at concrete slab's punching share capacity, influence factor and finite element simulation. We hope to solve the problem of the concrete slab for the punching shear to make it more popularizing and application in the project.