The Research On Torsion Failure Mechanism And Seismic Performances Of Steel Reinforced Concrete Structure Under Combined Force

Steel reinforced concrete composite structure(SRC) is a kind of independent structure which embedded steel in reinforced concrete. Because the steel itself has high strength and good ductility, plus the unique combination of the trinity that steeL rebar and concrete, making the steel reinforced concrete composite structure has characteristics of higher bearing capacity and stiffness than the reinforced concrete, having the advantage of seismic performance. Compared with steel structure,SRC has a lot of advantages,such as good fire-resistant performance? the local and whole sound stability? low cost and so on. Based on the researches home and abroad,SRC under low reversed cyclic load has good hysteretic characteristics and energy dissipation capacity. With the rapid development of our economy, high-rise buildings are more and more widely applied, makes the SRC has been more and more widely used. In the practical engineering structure, most steel reinforced concrete members are in complex stress state. Such as the frame side beam, joist, high-rise building transformation layer girder, corner post under the horizontal load. Thus, research on the properties of SRC combined torsional members is quite important.This article through to the combined torsion test of seven cross SRC columns and one RC column under low reversed cyclic load, observed and recorded how and what time cracks happen and how to expend, the law of changes in the stresses of the concrete, reinforced bar and the steel during the whole loading process, analyzed the influence of the experiment parameters such as axial compression ratio, torsion-bending moment ratio,stirrup ratio and the existence of the stud on component torsion experiment and seismic properties. Nonlinear analysis were completed using the large-scale general-purpose finite element analysis software ABAQUS, Compared with test results of research, summarized the composite force of steel reinforced concrete columns under torsion failure mechanism and its seismic performance.Finally, according to the experimental study and theoretical analysis, the failure mechanism of SRC combined torsional members and the formula for calculating the ultimate bearing capacity were proposed in this paper, summarized the seismic performance and made the brief analysis of the factors of influence. Through this research, we obtain some useful conclusions, as well as subsequent research has provided some theoretical support.