Study On Seismic Performance Of L-shaped Continuous Slab-type Concrete-filled Steel Tube Composite Columns

The columns of CFST can meet the actual needs of the building,avoid the problems of projecting the traditional reinforced concrete columns out of the wall,reducing the effective using area and not beautiful of the building.And its own characteristics also determine that it will be widely used in prefabricated buildings in the future.In addition,more and more concrete-filled steel tubular composite columns are used in high-rise buildings,and the lower part of high-rise buildings has higher requirements on the bearing capacity and seismic performance of column components.Therefore,the research on high-performance concrete-filled steel tubular composite columns is imperative.In this context,we design a new type of continuous slab CFST column in this paper.It is a CFST column what has two connection battens.The paper includes the following research contents:⑴ Three new L-shaped continuous panel composite columns of steel tube and concrete filled steel tube are designed and manufactured.The quasi static test is carried out on the steel pipe joint,namely the width of the patch plate and the axial pressure ratio in the test,and the corresponding p-Δ image is obtained.Then,the results show that the width of the joint patch is positively correlated with the peak and rigidity of horizontal load,negatively related to ductility and energy consumption capacity,and the increase of the width of the joint panel will aggravate the strength degradation and stiffness degradation;the vertical dead load is negatively related to the peak load and energy consumption capacity,which has a great impact on the seismic performance,and increases the seismic performance The large axial pressure ratio will cause both of them to be smaller and the stiffness degradation will be intensified.⑵ The three L-shaped continuous panel composite columns model of the test specimens were established by using ababqus,and the feasibility of the simulation analysis of the L-shaped continuous patched steel tubular concrete composite columns was verified by comparing the p-Δ images of the test results.⑶ 11 L-shaped continuous panel composite columns were established and simulated by changing the axial pressure ratio,the width and thickness of the joint patch plate,the diameter of steel pipe,the thickness of the wall of the steel tube,the concrete strength grade and the steel strength grade.The results show that: increasing the pipe diameter and the thickness of the pipe wall can increase the horizontal bearing capacity,but the deformation capacity becomes worse;the steel strength can increase the horizontal bearing capacity,while improving the ductility,which has a great influence on the seismic performance;the thickness of the connecting plate has little influence on the seismic performance;the concrete strength has the least influence on the seismic performance.