Experimental Study On Seismic Performance Of T-shaped Concrete-filled Steel Tube Column-steel Beam Joints Connected By Side Slabs

With building development of industrialization,people for pursuit of building efficiency,the use of space,extreme goal clear,deformed steel bar concrete structure column stare blankly don’t let it outstand wall.Can meet the requirements of people use of architectural space,but the poor seismic performance makes its limitations in building structure is becoming more and more obvious,in order to satisfy people’s pursuit for architectural form diversification,scholars put forward the special-shaped concrete-filled steel tube structure.As a new type of building structure,it can make full use of the characteristics of steel and concrete,meet the requirements of structural design and reasonable,at the same time,convenient construction,construction cost savings,is widely used in practical projects.Through the research,it is found that the beamcolumn beam node is the transmission hub of the structure and the key point in the design of the t-cfst column-steel beam joint is designed,and the rationality of the joint design and the seismic performance of T-CFST column-steel beam joint are studied by experiments.The main research contents are follows:(1)In presence of side panel,side panel connection length,axial compression ratio,and with or without binding bars as the main parameter,according to the requirements of the relevant rules and regulations,design and production of 7 T concrete-filled steel tube columnsteel beam specimens,by low cycle reciprocating load test,the side panel connection T steel pipe concrete column-seismic performance indicators of steel girder node is analyzed.The results show that the hysteretic curves of the joints are full and there is no pinching,indicating that the specimens have good seismic performance.The load-displacement hysteretic curve of the specimens with side plats is fuller than that without side plates,and the ultimate bearing capacity of the specimens,and the deformation capacity and energy dissipation capacity of the specimens are also strengthened at the later stage.Increasing axial compression ratio can improve the ultimate bearing capacity of specimens,but the stiffness and strength degradation of specimens are obvious,the restraint tie rod has little effect on the seismic performance of the specimens.(2)By observing the ultimate form of destruction in the seven specimens can be found,with a lateral plate specimen eventually when damage is occurred in the beam-column joints of steel bema flange,up and down the rest position basically no change,therefore,the destruction of specimen belongs to typical beam hinge failure,to meet the requirements of structural design of the “strong column weak beam”.(3)Through this experiment carries on the comprehensive analysis of test data,to get the skeleton curve model and the stiffness degradation rule of the specimens,the combination of three line model is established using lateral plate connection T the restoring force model of concrete-filled steel tube column-steel girder node,for the next deeper into the seismic performance of the node form research laid the foundation.