| Experiment results existed show that when horizontal boundaries of reinforced concrete slab are restrained its ultimate bearing capacity is significantly higher than that has not, which is called membrane effect. How to calculate membrane effect accurately so as to create a more advanced and reasonable design theory has become a serious problem that need to be solved in engineering.At first, in the thesis, elastic theory of thin slab and Differential equation of thin slab equilibrium and internal force equation of thin slab bending are introduced. In the meanwhile, limit analysis method plastic hinged lines theory is introduced. My research is based on this theory.Secondly, finite element model,concrete constitutive relationship,damage criterion and the solution of nonlinear equations are introduced. Simulation analysis of tested rectangular slabs using finite element software ANSYS are carried out, the whole boundaries of which are restrained. The calculation values are compared with maximum membrane force method ones and experimental ones. The result shows that the finite element method can actually reflect mechanical characteristics of horizontal restrained slab. Using this finite element model and changing slab thickness,slab dimensions,slab rebar ratio and concrete strength, impacts of various parameters on membrane effect of slab are analyzed.In the last, Based on plastic yield line theory the failure model of horizontal restrained rectangular slab is given. By applying principle of virtual work, the formula of horizontal restrained rectangular slab for calculation of limit bearing capacity is derived. The average compression zone height needs to be determined. By nonlinear regression of the results with MATLAB, the formula of compression zone depth can be obtained. Comparative analysis shows that the formula is in good agreement with experimental values, which can offer reference for engineering design and further research.
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