Experimental Study On Performance Of Concrete Filled Square Steel Tubular Short Column With Core Defect

Rectangular concrete-filled steel tube（RCFST) structure is characteristic of goodbearing capacity, anti-seismic capability, ductility and easy construction. Widely usedin the stress of the system such as high-rise super-tall bridges and long-span space andother buildings. Compared with steel piles, steel tube concrete has the good economicefficiency and building efficiency, because the steel pipe enhances the local stabilitywith the concrete, the concrete bears the larger axial load, and saves a lot of steel, alsothe price of the concrete is low much than the steel. So the Concrete-filled steel tub isalso an important development in the structure engineering discipline. But in the steeltube concrete construction, sometimes due to poor management, construction reasonand the concrete-filled steel tube frames in the influence of their own features andconstruction technology, it makes concrete materials hole, loose, cellular, constructionseam, segregation of concrete, steel pipe uneven and poor cementation and otherdefects, thus weakens the mechanical performance and overall performance of theconcrete filled steel tubular in different degree, and effects directly the supportingcapacity, and reduces the quality of the structure, so there’s a heavy security presence.In order to research the direct affection that the concrete defect makes for theconstruction of steel, to evaluate the practical bearing capacity and safety performance,it is very important to research the defect of concrete filled steel.By the experiment this paper researches the behavior of the RCFST in a differentsection of9RCFST with defects (location, size, shape) under compression, analyzesthe test process, nonlinear finite element, then proposes a reliable theoretical basiswith construction and design. Firstly base on experiment this paper researches thenine concrete-filled steel tubular short columns, analyzes the destructive phenomenonand mechanism of action, and the core concrete constraints by steel tubular. Secondly,discusses the impact of the mechanical properties with defects in concrete membersseparately. Finally, in the bases of select the constitutive relationships of the steel andcore concrete and failure criterion reasonably, use of ABAQUS finite elementsoftware, through simulate the test specimen, as a result of simulation is moreconsistent with the experimental results.