Study On Seismic Behavior Of Steel Tube Bundle Composite Shear Walls With Different Constructional Measures

The steel tube bundle composite shear wall is a new structure type of double skin steel-concrete composite shear wall,which can be produced with standardized design,factory production and assembly construction,and meets the current national policy guidance for promoting the sustainable and healthy development of the construction industry.As an anti-lateral force component on the bottom floor of a high-rise building,the seismic safety of the shear wall is critical to the whole building.Researches on the double skin steel-concrete composite shear wall had shown that the collaborative work between the steel plate and the concrete plays a key role in the bearing capacity of the structure.The failure mode of the steel tube bundle composite shear wall is usually the effective bonding damage between steel tube and concrete caused by the yielding of the outer steel plate,then the concrete is crushed and the structural bearing capacity is lost,resulting in that the the material advantages of both steel and concrete are not fully utilized in the whole process.Therefore,how to improve the local buckling of the steel tube bundle under the seismic load and increase the bond between the steel plate and the concrete is particularly important for improving the seismic performance of the steel tube bundle composite wall.In this paper,the research aims to improve the local buckling of the steel tube bundle and improve the seismic performance of the steel tube bundle composite shear wall.It was studied by a combination of experimental research,numerical simulation and theoretical analysis.The main research works and achievements are as follows:(1)The seismic performance tests of three steel tube bundle shear wall specimens with different constructional measures under lateral cycle loading were carried out,and the improvement effect of the local buckling of the steel tube bundle and the impact of seismic performance on setting different structures at the boundary were were studied.The failure mode,hysteretic behavior,stiffness degradation,deformation capacity and energy dissipation capacity of such composite shear walls were studied.(2)The finite element model of three specimens was established by selectingthe appropriate material constitutive model based on the ABAQUS platform.The accuracy of the finite element model was verified by the experimental results.The mechanics performance and the stress and damage distribution of the steel tube bundle composite shear wall with different constructional measures under different loading stress stage were analyzed,and the method to improve local buckling of steel tube bundle was proposed.(3)The effects of steel plate thickness,internal partition spacing and boundary constructional measures on the local buckling of the steel plate,the bundle of steel tubes and the internal concrete bond slip are studied through parametric analysis by ABAQUS software.The key factors affecting the shear resistance of steel tube bundle shear wall were caught.(4)The calculation formula of the normal section bending capacity under the horizontal load of the steel tube bundle composite shear wall considering the constraint effect is derived with reference to the code and existing research results based on reasonable assumptions.The calculation results and test results are in good match.