Analysis On Mechanical Property Of Joint Between Gangue Concrete-Filled Steel Tubular Column And Gangue Concrete Beam

Concrete-filled steel tube is the composite structural material which is composed of steel tube and concrete filled into the tube. Owing to the restraint effect of steel tube on the core concrete, the core concrete filled in the tube is in the tri-axial compressive stress state so as to improve the compression strength and compression deformability. At the same time, the core concrete avoids partial buckling failure in the tube to make full use of the property of the tube and increase the bearing capacity and seismic performance of the composite column. Gangue concrete-filled steel tube is to replace the normal concrete with gangue concrete which is filled in to the tube. Hence, the new composite material is not only to possess good seismic performance and high bearing capacity, but also to have new merits, such as the light weight and excellent economic gain. To use the gangue as the aggregate to make the concrete is beneficial to saving the stone and sand which are the irreversible natural resources so as to make the good influence on the society and economy. Nowadays, concrete-filled steel tubular structures are widely used in the world, but the researches on the joint between beam and column are not complete and mature. While the majorities of the researches focus on the study of the joint connecting the concrete-filled steel tubular column with steel beam, the joint between the concrete-filled steel tubular column and concrete beam is applied widely in China, with little researches on it. So, the paper makes a comprehensive study on the mechanical performance of two kinds of the joint between gangue concrete-filled steel tubular column and gangue concrete beam, including the joint with through rebar and the joint with ring beam.Based on the appropriate material constitutive relationship and failure criterion, the finite element analysis software ABAQUS is used to create the joint between gangue concrete-filled steel tubular column and gangue concrete beam and analyze the mechanical performance of the joint.The force-transferring mechanism, stress distribution and failure mode of the joint under the monotonic loading are analyzed in the paper and the load-displacement of the joint is calculated. The analysis results show that the joint between gangue concrete-filled steel tubular column and gangue concrete beam has high bearing capacity, good rigidity and excellent property under the loading.The calculation results under the low reversed cyclic loading are compared with the experiment results. The comparison results show the load-displacement skeleton curve calculated by the software matches well with the experimental curve and the failure mode received through the emulation analysis fits with the experimental environments. So the finite element analysis model created in the paper is accurate enough to make the research on the mechanics performance of the joint between gangue concrete-filled steel tubular column and gangue concrete beam under the reciprocating loading. Then the stress distribution and failure mode under the reciprocating loading are analyzed and the load-displacement hysteretic curve and skeleton curve are calculated in the paper. The analysis results show that the joint between gangue concrete-filled steel tubular column and gangue concrete beam possesses the full hysteretic curve so as to show the good ductility and superb ability to dissipate the energy under the earthquake.The important parameters, such as axial compression ratio, beam-column rigidity ratio, steel ration, strength of gangue concrete and so on, are chosen to create different mode so as to make in-depth research on effects of these parameters on the mechanics performance of the joint. Then the effects of these parameters on the load-displacement hysteretic curve, rigidity degeneration and strength degeneration are analyzed in the paper. The seismic performance of the joint between gangue concrete-filled steel tubular column and gangue concrete beam are made compressive research to provide some useful suggestions with the future research and practice application.