Research On Seismic Performance Of Plane Steel Frame With Semi-Rigid Connection

Construction steel structures that have advantages of light weight, easy installation, short construction period, good seismic performance, less environmental pollution and other advantages, are currently working on the promotion of research and application at home and abroad. The node connections between beam and column that transmit shear force and bending moment of beam column play an important role in the steel frames. There is a direct relationship between the force performance of the overall steel frame and the mechanical properties of the node connections. According to different stiffness of node connections, types of connections include idea rigid connection, full-hinged connection and semi-rigid connection. Rigid connection can only transfer a certain moment and does not allow rotating, while hinged connection allows nodes with a certain angle, but can not transfer the bending moment. Semi-rigid connection can not only transfer some moments but rotate. A large number of tests show that the ductility of steel frames with welding joints are poor, and occur brittle fracture easily and are hard for construction. The hinged joints are relatively simple but the stiffness and energy dissipation performance are poor that have disadvantage for structure seismic. While semi-rigid connections have better performance that match to the practical engineering, they connect the beam and column together by highstrength bolts and connecting pieces,and include top and seat angle connection, two web and top seat angle connection, flush end plate connection, short end plate connection, extended end plate connection and T steel connection according to different connecting pieces steel connection is used widely for its simple structure, simple construction, definite force transmission and more economic.Semi-rigid connections have been studied a lot at home and abroad, but most of these studies focus on the performance of semi-rigid connection nodes and less studies on the overall performance of steel frames. Our country code for design of semi-rigid connection does not make the relevant provisions, that result in the lack of relevant normative guidance in the design, which is one of the causes of resistance in research and application of steel frames with semi-rigid connections.Researchers have studied the seismic performance of two web and top seat angle connection steel frame by finite element and pseudo-dynamic test,using pseudo-static test for analysis of semi-rigid connection nodes,and almost there is no pseudo-static test for the whole steel frame with semi-rigid connection,especially the experimental study on T steel connection steel frame.In this paper,the seismic performance of plane steel frame with T steel connection was studied by pseudo-dynamic test and pseudo-static test that is the sub project of Henan province science and technology key project “Research on the seismic performance of steel frame with semi-rigid connection”.The main project is to research the strain changes,displacement response, acceleration response,inter-story drift angle and load response of T steel connection steel frame under EL-Centro wave and Northridge wave and the load-displacement hysteretic behavior, energy dissipation coefficient, ductility and failure mechanism under low reversed cyclic load to analyze the plastic hinge sequence and energy dissipation mechanism of T steel connection plane steel frame under cyclic load, thus getting the seismic performance of steel frames with T steel frame. The test results shows that during loading, T steel connections occur plastic hinges and yield failure at first and columns have the minimum strain so that finally yield causing the steel frame damage. Hysteresis loops which are full and the area is larger of T steel connection steel frame show good energy dissipation, ductility and good seismic performance that is suitable for earthquake area. The tests offer technical support for the popularization and application of steel frames with semi-rigid connection in engineering.