Research On Seismic Design Method Of Low Yield Point Steel Plate Shear Wall Structure Based On Performance

Low yield point steel shear wall structure has high lateral stiffness, strength and ductility. The stable hysteresis curve and excellent energy dissipation performance are shown in this structure, which can effectively reduce the earthquake suffering. The proposal of the design method based on performance of the low yield point steel shear wall can control the architecture's failure modes under different levels of earthquakes to make the architecture achieve the different performance levels provided by user, which has vast engineering applications. In this paper, design method based on performance of low yield point steel wall is systematically studied. The main studying works and conclusion are as follows:(1)By studying domestic and foreign literature, performance-based seismic design method based on displacement of the low yield point steel wall is proposed. And method of performance evaluation based on capacity spectrum method for the low yield steel shear wall structure designed by the performance-based design method is introduced, which can prove the rationality for the design of the low yield point steel shear wall.(2)Scale model of a two-story frame with the low yield point steel shear wall is designed, and the horizontal low-circle reverse loading test is conducted on it. Experimental study is focused on the lateral stiffness, ductility, ultimate capacity, energy dissipation, and deformation and stress distribution of the shear wall to analyze the change of of bearing capacity available for the structure after yielding, the first principal stress angle of the wallboard and the stress change of the beam, column and wallboard, by which the seismic performance of the low yielding point steel shear wall structure can be systematically known about.(3) Based on theoretical analysis and experiment, numerical simulation for the specimen is done by finite element software ANSYS and SAP2000, respectively. APDL language is used to write the command stream when ANSYS is applied in finite element analysis. Taken the local buckling into consideration, shell181 element is used in the command stream to simulate the specimens. The shell element can well simulate the stress change of the specimen and the deformation process of the low yield point shear wall.Based on finite element software SAP2000, link element and layered shell element are used to analyze the performance of structure, and the effectiveness for these two kinds of finiteelement analyzing methods are proved by the experimental results.(4) Based on experimental data, related domestic and abroad literatures and the example of reference inter-story drift index from Seismic Design of Buildings GB50011-2010 in China, the performance index of low yield point wall is quantized and the different experimental behaviors under the corresponding inter-story drift angles are detailly illustrated. When the elastic inter-story drift angle is up to 1/250(which is the elastic limit value in the code), the shear wall has almost totally yielded but the column has not yielded yet and the structure is almost intact. When the elastic-plastic inter-story drift angle is up to1/50(which is the plastic limit value in the code), the middle of shear wallboard has obvious convex portion, the columns are all in yielding state and the flange has slight twist.(5)According to the proposed performance-based seismic design method based on the displacement for low yield point steel plate shear wall, 10-storey and 30-storey low yield point steel plate shear wall frames are designed, which are located in high intensity seismic region. Based on the 4 quantitative performance indicators, the design process of 10-storey low yield point steel plate shear wall frame based on performance-3 and performance-4, and the design of 30-storey low yield point steel plate shear wall frame based on performance-3with high order vibration model are explained in detail. In order to prove the reasonability of designed structure, capacity spectrum method is used to evaluate the seimic performance and analyze the performance states of the above frames in different design performances. In different design performances, with the rising of earthquake level, the low yield point steel plate shear wall in frames yield gradually. But no plastic hinge appears in outer frames,which indicates that the low yield point steel plate shear wall plays an important role in all design performances. So, the good seismic performance of low yield point steel plate shear wall is proved, and the obvious advantage of structural system makes it suitable to be used widely.