Experimental And Finite Element Analysis On Mechanic Alproperties Of Single Side High-strength Bolt With T-stub Connections

In the steel structure,beam-column connection node is the most important transmission mechanism,which can directly affect the overall performance of the structure.In general,weld or conventional high-strength bolt is used for connecting steel structure of the beam joint.But,it is difficult to guarantee the quality of the weld because of brittle fracture.The conventional high-strength bolt is fully assembled for the H-beam beam and column,but the rectangular cross-section column and H-beam connecting joint need to open the the hole then install high-strength bolt,which increases the amount of post-construction.Single side high-strength bolt with the advantages of unilateral installation,unilateral tightening,and construction convenient and other advantages,that can avoid the problems existing in the installation of conventional high-strength bolts.At present,the research on the mechanical performance of single high strength bolt connection is very scarce,and its popularization and application in assembly type building is limited.In this paper,the tensile region of single side high-strength bolts with rectangular tubular columns and H-shaped beams joint is simplified as T-stub.The influence of the thickness of the T-stub ? stiffener and the structural parameters of the T-stub are considered on the mechanical properties of the single side high-strength bolts T-stub connections,which compared with common high-strength bolts T-stub connections.The experimental study and ANSYS numerical simulation are use to analyze the high-strength bolts T-stub connections.The results show that:1.The damage morphology between single side high-strength bolts and the conventional high-strength bolts connected to the T-stub connection node is different.The flange plate damage both have a significant bending deformation,and single side high-strength bolts and bolt holes are squeezed so that the bolt hole occurs plastic deformation,at the same time,the single side high-strength bolts out of the casing extrusion bending deformation was pulled out while the conventional high-strength bolts screw tension due to the role of elongation and tensile failure.2.The results of test and finite element analysis indicate that the bearing capacity of the difference on bearing capacity between the single side high strength bolts T-stub connection node and the conventional high-strength bolts T-stub connection nodes is minor.3.Based on the results of finite element numerical simulation,single side highstrength bolt and conventional high strength bolt show certain difference in the mechanical properties.Single side high-strength bolt lose efficacy because of its outer casing component extrusion shear failure,but high strength bolt become invalid owing to the bolt shank elongation.4.Increasing the flange plate thickness of T-stub and stiffener have a great influence on the mechanical properties of the single side high-strength bolts T-stub connection node.The tensile strength of the bolts under the same external load is reduced and the pry force is weakened and the increase of the line distance is disadvantageous to the mechanical performance of T-stub connection node,because of the reduced bearing capacity is reduced.In addition,when the external load is the same,the tensile bearing capacity of the bolt is increased and the prying force is enhanced when applying same loads.But other parameters of T-stub has little effect on its mechanical properties.