Seismic Behavior Of RC Braced Frame Structures Research And Comparison Model Selection

The structural types of RC frame structure and frame-shear wall structure are widely used in Multi-story and large-span structures in the high seismic intensity regions, especially the RC Frame Structure. Under strong seismic action, Lateral drift of RC frame is not only difficult to meet the requirements due to its limited stiffness, but also prone to damage or even progressive collapse as a single lateral force resisting system when the building exceeds a certain height. Frame-shear wall structure is a composite structure with the advantage of RC frame and shear wall structure actually consists of RC frame and shear wall structure. Seismic energy can be dissipated effectively by frame-shear wall structure with a large lateral stiffness. However, the ductility become weak with increase of stiffness and which has adverse effect on the anti-seismic performance.The RC Frame Structure with vertical braces has the advantages of appropriate stiffness, good ductility, good performance of plastic deformation and saving materials. According to different types of braces, RC frame-braced structure system can be classified into many braced structure systems. Based on the study of such structures, this paper lists seven frame-braced structure systems currently as research object, using the finite element software ETABS establish reasonable numerical models. Then the dynamic responses of structure with different arrange plans of brace are analyzed and compared selection. The main research contents include following several aspects:(1) As different types of braced structures, the dynamic responses of structure using the method of Nonlinear Static Analysis and Dynamic Elastic-plastic Time History Analysis are researched.(2) Compared with different types of brace’s RC Frame-braced structural system and the seismic behavior of frame structure can be viewed to find which types of brace is the best form.(3) Compared with the results of Nonlinear Static Analysis and Dynamic Elastic-plastic Time History Analysis, then a summary of these two Elastic-plastic Analysis method can be made.Through comparative analysis, mainly the following conclusions:(1) The maximum story drift of RC frame-braced structure reduces by about 30% compared with RC frame structure, and increases by about 50% compared with frame-shear wall structure. Plastic hinge deformation is between RC frame and frame-wall between structures. It illustrate that the seismic behavior of RC frame-braced structure is higher than the frame structure and less than the frame-shear wall structure. So in Multi-story and large-span structures in the high seismic intensity, using of RC frame-braced structure is more reasonable.(2) Seismic behavior of RC frame-eccentric braced structural is better than RC frame-central braced structural. RC frame-eccentric braced structural has a good seismic behavior. In different types of brace’s RC Frame-eccentric braced structural, the top node displacement of K-eccentric braced structures is the least, and most story drift angle is the max. Therefore, the seismic behavior is the best.(3) These two elastic-plastic Analysis results are in good agreement. Static and dynamic elastic-plastic analysis method as a secondary method is used to guide the design of the structure, analyze the structure yielding mechanism and find structurally weak parts of the work, which is very realistic.