Aseismic Optimal Design For Frame-shear Wall Structure With Deep Coupling

Frame-shear wall structure has been widely used in the high-rise buildings duo to the advantages of the large space, good structural integrity and lateral stiffness. With the development of the high-rise buildings optimization theory, structural engineers pay more attention to seismic concept design and the overall optimization in the actual projects. Therefore, how to effectively optimize frame-shear wall structure, in order to achieve multichannel seismic defense lines to the dissipation of earthquake energy and good ductility under seismic action, has become the development direction of current structure optimization.The frame-shear wall structure is studied in this paper, which is a widely used structure type. Under seismic action, the reasonable design(including its form, location and number) of shear wall has a significant impact to the mechanical and seismic property of frame-shear wall structure, because of shear wall as the first seismic defense line to the structure. In order to improve the seismic ductility of shear wall,mainly through control of the part of the coupling beam and the bottom of wall, which is the weak positions to the structure to achieve the structure of the first seismic defense line has two seismic defense lines. Ideal structure failure mode is to make the coupling beam first damaged in shear wall, which as the first seismic defense line. In the structure often appears deep coupling beam(the span-depth ratio is less than 2.5), the previous earthquake damage shows that the deep coupling beam often occurred the shape of “X” shear failure. In order to improve its ductility, the deep coupling beam in frame-shear wall structure adopt new reinforcement scheme in this paper. New reinforcement scheme of the deep coupling beam is along the scope of its height set layered stirrups, and in the top and bottom of stirrups using unbounded technology to reinforcement, which set PVC sockets in a quarter height of the wall. In order to further optimize the frame-shear wall structure, between shear wall and frame column also add in the deep coupling beam to improve the ability to lateral stiffness in this paper. Under horizontal load, use this paper suggested a frame-shear wall structure with deep coupling beam to deformation coordination analysis and based on contrastive analysis that a instance compared with ordinary frame-shear wall structure in 8 degrees seismicfortification, the paper obtained the below preliminary research results.(1)The coupled shear wall with deep coupling beam in frame-shear wall structure has three seismic defense lines under seismic action. By analyzing the solution of cooperative differential equation of frame-shear wall structure, the best eigenvalues interval of hinged frame-shear wall system is obtained,which is about [1-3]. But for the rigid frame-shear wall system, because of the beam stiffness contribution can be enlarge appropriately.(2)By analyzing traits of displacement curve of frame-shear wall structure, pointed out that the maximum layer displacement angle occurred in the point of inflection, and the maximum layer displacement angle formula of frame-shear wall structure under the inverted triangular load were given.The MATLAB software is used to calculate the instance. Its validity of formula is confirmed by the calculation of PKPM software. Using the relationship between the seismic action and the stiffness of shear wall, and selecting the stiffness of shear wall as the design variables, and using the shear-weight ratio, the ratio of rigidity-to-gravity and the story shear force of frame in frame-shear wall structure as constraint conditions, set up the optimization mathematics model of frame-shear wall structure, which can get the minimum horizontal seismic action.(3) Regard the coupled shear wall with deep coupling beam as a rigid outrigger structure, through coordination analysis to calculate the top displacement of the rigid outrigger structure. Converting it into an equivalent vertical cantilever bar, the seismic stiffness of the wall was given. And analyze frame-shear wall structure in the optimal location and the number of the coupling beam deep, simplified formula is obtained.Analyzing the optimal location and the number of deep coupling beam in frame-shear wall structure, and the simplified formula is given, and also refer to the location of maximum layer displacement angle in practical engineering.(4)The same layout form and cross section of ordinary frame-shear wall structure, the maximum layer displacement angle were not meet the limits of standard under the seismic action in X and Y direction. But if layout a deep coupling beam in Y direction, the frame-shear wall structure were less than the limits of standard under the seismic action in X and Y direction, and deformation curve is more reasonable. So, the deep coupling beam be added can improve lateral stiffness and integrity of frame-shear wall structure.Based on seismic conceptual design and the overall optimization of structure, this paper proposes an optimization method and the concrete steps of frame-shear wall structure with deep coupling beam.Compared with ordinary frame-shear wall structure, the optimization train of thought and method of this paper is validated. It has a certain practical guiding role in the design of reinforced concrete frame- shear wall structure.