Flexural Behavior Of Steel Reinforced Concrete With Steel In The Middle

Because of the advantages such as high bearing capacity and stiffness as well as excellent seismic performance, SRC(steel reinforced concrete) structures have been used increasingly more for practical engineering. In our country, the research on the component flexural behavior developed quite late. The steel of traditional steel reinforced concrete beam is totally in the state of press when it is bending, but the steel of SRC beam with steel in the middle is partly in the state of press and partly in the state of pull, because of this, the concrete and steel of SRC with steel in the middle work together better than SRC with steel in the bottom and it also increase the ductility of SRC. At present, the performance of the steel reinforced concrete under flexure was not fully understood and very few people have done some research on the flexural behavior of SRC component with steel in the middle, so, to carry on theoretical analysis of the performance for steel reinforced concrete with steel in the middle has an important practical meaning as well as a broad application prospect.The thesis introduced the failure mechanism and calculation method of steel reinforced concrete structure under flexure. The author has done loading experiments of Six SRC beams with steel in the middle, and got its ultimate load, load-deformation curves, failure form, fissure condition, concrete strain of SRC beam’s middle and deflection curves, and then analysed the flexural behavior of SRC with steel in the middle, and proved the Assumption of Plane Section. Three numerical models for steel reinforced concrete with different type of steel section which subjected to flexure were established by ANSYS program, and the analysis results were compared to the experimental results. It was found that ANSYS can simulate the behavior of the member under flexure with reasonable numerical model. The stress distribution of the concrete and steel as well as the development and form of the cracks were analyzed in typical load step. The influence of steel size for flexural performance of member was discussed. Besides, finite element models for steel reinforced concrete with steel in the middle and in the bottom were established for nonlinear analysis, it was found that concrete and steel of SRC with steel in the middle can work together better because of the stress redistribution which was caused by pressure zone of steel.