Mechanical behavior of prestressed concrete T beam based on mixed shell element method

In order to accurately forecast and estimate the mechanical property of prestressed concrete T beam, its finite element model was set up by using mixed shell elements, and the nonlinear process of its mechanical behavior from wholeness to failure was studied. In T beam, curving prestressed steel was simulated with combined shell element model, its contribution to the stiffness matrix of combined shell element was deduced by using virtual principle, and straight prestressed steel was simulated with layered shell element model; the material nonlinear behavior of concrete was considered with Owen yield criterion and Hinton crushing criterion, and the behavior of steel was depicted with bilinear constitutive model. Analysis result indicates that the computational result of the model is close to experimental result, the stiffness degradation coefficient of T beam in nonlinearity phase is much larger than that in elasticity phase, and the most increase of steel stress is at the bottom of mid-span, so mixed shell element method is efficient and proper to analyze the mechanical behavior of prestressed concrete T beam.