Study On Mechanical Behavior Of Composite Shear Wall With CFST Columns Incorporating FRP-confined Concrete Core

In recent years,reinforced concrete shear wall and core tube structure are wildly used as the main lateral force resisting elements in high-rise and super high-rise buildings,nevertheless,the mechanical properties and seismic performance of the whole structure would be decresed dramatically due to the crack in the shear wall or core tube under strong earthquake action.Based on this background,combined with the advantages of concrete filled FRP tube,a new composite shear wall,Composite Shear Wall with CFST Columns Incorporating FRP-confined Concrete Core,is proposed in this paper.The nonlinear finite element analysis was carried out using software ABAQUS,meanwhile the mechanical properties and seismic performance of this new composite shear wall with different parameters including FRP layers,concrete strength and axial compression ratio were analysed.Moreover,the bearing capacity formula of the new composite shear wall is established and modified by theoretical analysis and numerical simulation.The main contents in this paper include the following aspects:1)The finite element analysis model of composite shear wall with CFST columns was established by choosing the feasible constitutive models of different materials,and the numerical simulation for this model was carried out.Compared with the existing test results the feasibility and correctness of modeling method for the new composite shear wall were verified.2)In order to study the influence of different design parameters on composite shear wall with CFST columns incorporating FRP-confined concrete core,such as FRP layers,concrete strength,axial compression ratio and so on.9 finite element models with different design parameters were established.The load--displacement curves for different design parameters were analysed,which were extracted from simulation results of the monotonic nonlinear parameter analysis under horizontal loads.At last,the influence law on mechanical properties of the composite shear wall with different parameters were analysed,compared with the bearing capacity,deformation capacity,ductility of this composite shear wall and so on.3)On the basis of the bearing capacity formula of normal concrete shear wall,combined with the confinement effect of steel tube and FRP tube,the bearing capacity formulas of the steel--concrete composite shear wall and composite shear wall with CFST columns incorporating FRP-confined concrete core were derivated,and then the bearing capacity formula of this new composite shear wall,was modified by comparative analysis for caculation results using the bearing capacity formula and numerical simulation results,and the error analysis was carried out at same time.Finally the bearing capacity formula of the shear wall with CFST columns incorporating FRP-confined concrete core was determined.