Nonlinear Computer Simulation For The Reinforced Concrete Structure

The main task of this thesis is to discuss the method that is used in simulating the nonlinearity of the reinforced concrete structures. The writer has analyzed the nonlinear properties of the reinforced concrete beam and a nine-layer frame structure by Finite Element Method and the principles, from members to whole, is followed.This thesis has reviewed the application of the computer simulation about the nonlinear of the reinforced concrete structure and the important role in the development of the concrete structure. In this thesis, the simulation's theoretical meaning and practical value are pointed out, that is used in the reinforced concrete structure' nonlinear analysis.Firstly, the nonlinear properties of the reinforce concrete are stated in the thesis. The nonlinear properties contain the stress-strain relationship, material nonlinearity problems and the developing trend of the concrete cracks, and so on. Then the method is discussed that about the finite element model of the steel bar, the finite element model of the concrete, the finite element model of the concrete cracks. Finally, a reinforced concrete beam is analyzed by the finite element program ADINA and a method of moment-curvature-beam is used to analyze a frame structure. The writer has simulated the nonlinearity problems of the reinforced concrete successfully.The steel bar is supposed to be perfectly elastic-plastic in the thesis. The Bilinear Kinematic Hardening Materials (BKIN) is choose as The Yield rule of steels. The special Rebar element of ADINA is adopted to simulate the steel bar; the data of the Kupfer biaxial experiment is adopted, the partition method of regular-octahedron is adopted. Discrete-Cracking Model is adopted. The load is applied step by step. The convergence criteria is displacement. After the finite element analysis, the process of plastic failure, the development process of cracks and the distribution state of stress and strain are indicated, and some Conclusions is gotten..Finally, some problems, needing further research in the nonlinear area of the reinforced concrete, are discussed. The achievement has certain reference value in the structure design area of the reinforced concrete, in this thesis.