Square Steel Column-H-Beam Flange Bolts Study Of Mechanical Properties Of Connection Joints

The square steel column-H-beam flange bolted joint(flange connection joint)is a new type of assembled beam-column joint.The flange of this joint is welded and assembled in the factory,and then transported to the construction site for lifting and bolting,which has the advantages of fast construction,standardised manufacturing and green environment protection.However,there is relatively little mechanical research on this new joint at home and abroad,and its mechanical performance indicators such as load-bearing capacity and seismic energy dissipation capacity are not yet clear,which is not conducive to the practical engineering application of this structure.In this paper,finite element analysis is carried out for the mechanical properties of flange connection joints.The ABAQUS finite element analysis software was used to analyse the load displacement curve of the flange connection joint under monotonic load,and the load carrying capacity,ductility,stiffness and hysteretic energy dissipation capacity under cyclic reciprocating load,using the flange inner sleeve thickness(FH),flange inner sleeve length(FL)and square steel column wall thickness(ZH)as variation parameters.The research results can provide a theoretical basis and reference for the design and application of flange connection joints.The main research contents and results of this paper are as follows:(1)The numerical model of the joint is established from the geometric model,material ontology,unit selection,interaction and boundary conditions based on the existing tests of flange joint joints.The reliability of the finite element analysis method and the accuracy of the finite element analysis parameters are verified by comparing the test results with the numerical simulation results.It is also shown that the numerical simulation method can be used for the analysis of the mechanical properties of flange connection joints,and can also provide a reference for the establishment of steel beam-column connection joints in numerical simulation.(2)Under both monotonic and cyclic reciprocating loads,the flange joint joints have high load capacity,good stiffness,ductility and load carrying capacity.The hysteresis curve of the joint is full and the shape of the curve is shuttle-shaped,indicating that the joint has good hysteretic energy dissipation capacity.The hysteresis curve shows "pinching" phenomenon in the late loading period,which indicates that the joint will produce certain slip deformation.3 parameters have a great influence on the load carrying capacity,ductility performance and energy dissipation capacity of the flange joint joints.The flange connection joints have good load-bearing capacity and the ductility coefficient is greater than 3.0,with strong plastic deformation capacity.The joint ductility increases negatively with flange inner sleeve thickness and flange inner sleeve length,and increases positively with column wall thickness.3 parameters have a certain influence on the initial stiffness,but the influence on the stiffness degradation is small.(3)The dimensional change of the joints is an important factor affecting their mechanical properties.According to the results of finite element analysis,some suggestions are made for the construction of flange connection joints.The thickness of the flange inner sleeve should be taken as 6～10mm,the length of the flange inner sleeve should be taken as250～300mm,and the thickness of the steel pipe column wall should be taken as 8～12mm,and the actual situation and economic applicability should be combined to optimize the selection.