Study On The Out-plane Mechanical Behavior Of Steel Plate Concrete Wall In Nuclear Power Plant

Nuclear power,a clean energy,has been paid more and more attention around the world, while amount of nuclear power generation in China is greatly lower than the international average level. In order to accelerate the development of nuclear power of our country and ensure the safe operation of nuclear power projects, China has introduced the AP1000 pressurized water reactor nuclear power project, designed by Westinghouse of United States.And China has researched and developed the CAP1400 pressurized water reactor nuclear power project on the basis of AP1000.In order to improve the mechanical properties of structure and degree of modular construction, steel plate concrete structures are widely used in the nuclear safety related structure module in the design of AP1000 and CAP1400 nuclear power projects,. Steel plate concrete structures are composed of bilateral or unilateral steel plates and internal concrete. There are is reinforcement between two layers of steel plates, and steel plate is connected with concrete by pegs that are welded with the inner surface of steel plate, and connecting members connect two layers of steel plates,playing the role of shear reinforcement,which is different from ordinary reinforced concrete structure. As a kind of composite structure, steel plate concrete structure has high capacity, ductility, excellent seismic performance, and good resistance to withstand strong explosions and shocks. In addition, the construction characteristics of steel plate concrete structure may also implemente modular construction and installation, adapting to the needs of modern construction, greatly improving the efficiency of the construction of structure and shortening the construction period.Recently, in the building structure field, especially in the nuclear power plant,the steel concrete wall is just applied rarely in engineering practice, and its application and design are both based on detailed engineering experience and common practice, which lacks specific guideline or code, and the related research has not been deeply launched in this field. According to this problem, the main works of this dissertation are as follows:1. In order to clarify the influence of the shear span ratio on the out-plane mechanical behavior of steel plate reinforced concrete wall,an out-plane one-way loading experiment of 4 specimens is performed. In the experiment, the deformation characteristics of specimens, the specific buckling behavior of surface steel plate, the failure modes and the capacity of strength are studied, and the reasons of the difference of 4 specimens’ mechanical performance and experimental phenomena are analysed.2. The experiment results are sorted out and studied. 4 specimens’ ultimate out-plane bearing capacity and stress pattern are comprehensively compared in this study. This dissertation summarized the relationship of ultimate out-plane bearing capacity and shear span ratio, and then compared the experimental results with the existing formulas of domestic and international codes. In the results, ultimate out-plane bearing capacity decreases with increasing shear span ratio; and the computation of existing formulas isn’t consistent with experiment’s result well, and this dissertation presents a new computation method of ultimate out-plane bearing capacity in the way of linear fitting.3. The finite element numerical simulation model is built with the ABAQUS software,according to the existing classic experimental achievements. In this model, material and geometric nonlinear and the interaction between concrete and steel plate have been taken into account. In this dissertation, the experimental results and finite element calculation results are compared, and the finite element calculation results fit the experiment results well, so the finite element analysis model can analyse the out-plane mechanical behavior of steel plate concrete wall well.4. The main parameters affecting the behavior of steel plate reinforced concrete wall are analyzed with the finite element model, including the thickness of steel plate and the space between studs, etc. According to the finite element analysis results and experimental results, this paper points out the reason of the out-plane mechanical behavior of steel plate reinforced concrete wall vary with parameters, and put forward the critical value of parameter of transformation between different failure modes under certain circumstances. The result shows that the thickness of steel plate and the space between studs should be regulated in order to make steel plate yielded and make sure that steel plate reinforced concrete wall without shear reinforcements fail in flexural-shear failure mode.