| Finite element method of reinforced concrete, an efficient numerical analysis method, for non-member structure design and crack analysis, has been adopted more and more widely.At present, for non-linear finite element method of reinforced concrete, according to simulative methods, element models can be divided into three kinds: separate model, combined model and integral model. Based on the analysis of the advantages and disadvantages of the three element models, this thesis presents a new combined element model. The model doesn't have any special requirement for the position or the steel bars in concrete, and it can consider the bond-slip between steel bars and concrete. The advantages of this model lie in its convenient meshing, inerratic shape, less numbers of elements and high precision in calculating the width of cracks. Compared with the separate element model, they have the same precision when the meshes are same.Based on the exiting program, the corresponding pre-processing module and calculating module and post-processing module were generated; based on AutoCAD, the post-processing module can provide the moment graph, shearing force graph, axial force graph and corresponding envelope diagram, and output of reinforcement arrangement, inner force and stress graph of specified section.Adopting the model mentioned above, the brackets are analyzed, and it is shown that the results are similar to that of the experiments, which shows that the element model presented in this thesis can deal with irregular steel bars effectively. The analysis of brackets shows: the bearing capacity of the brackets increases a little as the value of a/ho decreases, but the effect is limited; the longitudinal reinforcement provided is more than needed if the value of a/h0 is adopted as 0.3 when it is less than 0.3; but the bearing capacity is not enough if only the longitudinal reinforcement is arranged. To assure the bearing capacity of the brackets, the stirrups must be arranged.
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