| Under the earthquake load,the beam-column joints in the prefabricated steel frame structure system transmit bending moment and shear force.It is not only a key way for the internal force transmission of the entire steel frame system,but also a key hub for supporting steel frame components(such as beams,columns,and slabs,etc.),which determines the safety performance and seismic performance of the entire steel structure,and is also the key to the design and construction of the entire building structure.difficulty.Based on the existing research results,this paper proposes a new type of fully assembled square steel pipe beam-tocolumn connection for the prefabricated steel structure frame system,which is suitable for low-story prefabricated steel structures.The beam-column joint is fully bolted between the upper column and the lower column,and between the beam and the column through the outer ring plate and the L-shaped connector,avoiding the strain concentration caused by traditional welding.At the same time,the finite element software ABAQUS is used to carry out numerical calculations on this node,and the deformation and stress distribution characteristics of this node are further analyzed to provide support for the actual engineering application of this node.The main research contents are as follows:(1)The construction technology of fully assembled square steel pipe beam-column joints is proposed.In order to explore the influence of different axial compression ratios on the mechanical properties of fabricated joints,as well as the difference in mechanical properties between fabricated joints and traditional welded joints under the same axial compression ratio,and to summarize the advantages and disadvantages of existing joints,according to the relevant design According to the specification,a fully assembled square steel pipe beamcolumn joint is proposed on the basis of existing research,and two types of four steel frame joints are designed,and its design,fabrication,construction sequence and assembly method are described in detail.(2)The seismic energy dissipation capacity of fully assembled square steel pipe beam-column joints was explored.The low-cycle reciprocating loading tests were carried out on two types of four-node specimens,and the seismic performance indicators such as failure characteristics,energy dissipation capacity,skeleton curve,ductility coefficient,stiffness degradation,and strength degradation of the specimens were obtained.The seismic performance and failure characteristics of prefabricated joints under different axial compression ratios and different joint forms under the same axial compression ratios are studied.The test results show that with the increase of the axial compression ratio,the mechanical performance of the prefabricated joint increases gradually but the magnitude of the increase decreases,which shows that the increase of the axial pressure can improve the performance of the joint to a certain extent,but the improvement is limited.Under the same axial compression ratio,compared with traditional welded joints,fully assembled bolted joints have stronger plastic deformation capacity,and show better seismic performance and energy dissipation capacity in low-cycle reciprocating loading tests(3)Numerical simulation analysis of fully assembled square steel pipe beam-column joints is carried out.Using the finite element analysis software ABAQUS,the simulation models of assembled joints and welded joints were established,and compared with the test results,the correctness of the numerical model was verified.On this basis,the mechanical properties of the assembled node model under low-cycle repeated loads are analyzed,and the stress distribution and force characteristics of the node are discussed,so as to provide support for the engineering application of the node. |
PDF Full Text Request