Study On Mechanical Behavior Of Concrete Filled Square Steel Tube Planar Frames With Diagonal Stiffened Steel Plate Shear Walls

The steel plate shear wall is a structurally effective and economical lateral loadresisting system. The steel plate shear wall has advantages over the conventionalreinforced concrete wall in several aspects. The overall weight of a structure can besignificantly reduced by using the steel plate shear wall. Therefore, the size of thefoundation and the earthquake load can be reduced. Further, structures can beconstructed with the use of the steel plate wall. Also, the usable floor area can beincreased by using the steel plate wall with thin infill plates. These advantages make itbecome widely used in practical constructions. The hysteresis curve of unstiffened steelplate shear walls exists pinch phenomenon while the larger additional internal forcegenerated by the tension field leads to the failure of frame column too early. Aiming atthese problems, the concrete filled square steel tube planar frames with diagonalstiffened steel plate shear walls is put forward. By using the numerical analysis andtheoretical analysis, the seismic behavior of concrete filled square steel tube planarframes with diagonal stiffened steel plate shear walls is studied.AISC put forward the formula of the shear force of the intermediate beam, but theformula didn’t consider the shear force produced by the horizontal components oftension fields on the intermediate beam. Based on the failure mechanism of steel plateshear walls, this paper analyzes the shear force of the intermediate beam.The currentformula of the shear force of the intermediate beam put forward by AISC is revised. The nonlinear numerical analysis is conducted by using the nonlinear finite element softwareABAQUS6.10. The results show that the method for the calculation of the shear force ofthe intermediate beam is feasible.By using the numerical analysis and theoretical analysis, the shear force-drift curve,and the interaction between the infill walls and frame members are studied. The resultsshow that the infill walls generally have their first yield at a drift of around0.17%. Atthe drift of around0.51%, the infill walls experience widespread yielding, while theframe members have their first yield.By using the numerical analysis, the influence of siffness ratio of stiffeners to panel,panel slenderness ratio, normalized axial force and colume stiffness on the hystereticbehavior of diagonal stiffened SPSW is studied. Based on the above studies, therestoring force model is obtained.Conventional design of steel plate shear walls assumes that100%of the storeyshear is resisted by each infill panel. Following this approach, strength provided by theboundary frames moment resisting action, which provides the SPSW with overstrengthin the limit state, is neglected. While this design assumption has positive impact onseismic performance of SPSWs, no analytical work has been done to quantify themagnitude of this overstrength in general terms. Based on plastic analysis of SPSWs,this paper proposed procedure to make use of the strength provided by the boundaryframes moment resisting action. Then the nonlinear numerical analysis is conducted byusing the nonlinear finite element software ABAQUS6.10. Results obtained from thisstudy are as follows: The method proposed in this paper can meet the requirement of thebearing capacity, and is economical.