| Steel-concrete composite shear wall, which is a kind of excellent lateral resistantmember, effectively improves the steel plate and the concrete cover plate in the disadvantageof the local buckling and brittle failure. It has both well ductility and stiffness, whichincreases the lateral stiffness and ductility of the steel frame composite shear wall, lowers therequirement in steel frame joints. It offers an opportunity to use the more economicalsemi-rigid joints. This structure is called steel frame-composite steel plate shear wall (SCSW).At present, many researchers at home and abroad focus on study the bearing capacity ofthe composite wall, the buckling deformation of steel plate along with the substitution, thebuckling-restrained capacity of the reinforced concrete cover plate, the cooperative workprinciple of the steel plate and the cover plate, and the seismic behavior of the composite wall,which has come to helpful conclusions. But there is no research on the seismic design methodand plastic failure mode of SCSW, the energy consumption principle of whole structure, theprediction method of ultimate horizontal strengthening capacity as well as the load transfermechanism between the components.In this paper, a design method of SCSW based on reasonable assumptions is put forward.Based on an office building, a single frame6-floor SCSW structure is designed and a1:3scale bottom two floors model is selected as SCSW model.According to the function of the components, the lateral load transfer way of SCSW isput forward as: the steel frame transfers lateral load to the simplified model of composite wallby splice bars; the simplified model transfers the load down to the frame by bridle bars; theframe then transfers the load down to the basement by the deformation itself. The calculationmethod of the shearing force of frame column and splice bar along with the calculation wayof the moment of frame and composite wall are put forward by the load transfer analysis. Theplastic failure mode and prediction method of ultimate horizontal strengthening capacity ofSCSW is obtained based on the theoretical analysis and calculation. SCSW failure process isgenerally as: the infill steel plate microbuckling occurs; the reinforced concrete cover plateresists the buckling and crazes in edge; the infill steel plate is snapped all around and thecomposite wall stops working; the steel frame lateral displacement occurs, plastic hinges develops at joints and column base and then the structure fails. The structure absorbs seismicenergy by infill steel plate deformation and plastic hinges rotation.A nonlinear finite element analysis model is set up to simulate the working state undercyclic loading. The plastic analysis method is assessed by the analysis on stress diagram andhysteretic curve. The result shows: the plastic analysis value of lateral limit capacity is702.2KN,9.4%lower than that of nonlinear finite element analysis, which means that theplastic analysis method is feasible and the structure has some safety reserves; SCSW bearsmore than70%lateral load and steel frame bears more than80%moment, which is identicalwith that composite wall bears all shear force and steel frame bears all moment.; to reinforcedconcrete cover plate, larger normal stress is distributed around the cover plate. The cover platereinforcement can be adjusted according to the normal stress distribution as increasingreinforcement ratio around cover plate and reducing in the middle, which makes thereinforcement more economic and reasonable; comparing the simulated results of semi-rigidsteel frame infill steel plate shear wall model, SCSW has better bearing capacity, lateralstiffness, ductility and deformation performance.SCSW first proposes to combine the composite wall with semi-rigid joints, whichwidens the application range of semi-rigid joints and perfects existing seismic resistantstructure system. It is a meaningful attempt. |
PDF Full Text Request