The Mechanical Performance Analysis Of High-Strength Bolted Joints And Its Application In Steel Frame

In the steel frame structure,the frame column is one of the important members,which has a great influence on the bearing capacity,the mechanical proterties and the deformation resistance of the structure.The splicing joint is the key joint of the steel frame.In this paper,based on the current design method in China,a type of column splicing joint with high-strength bolts and cover plates is proposed,and the oblong circle slip hole is designed at the flange plate position,and the friction between the flange plate and the cover plate is used to achieve the purpose of energy dissipation.In this paper,the compression and bending of the joint section are analyzed by means of mechanical knowledge,and the simplified load-displacement curve and momentrotation curve are obtained.The ANSYS is used to model the high-strength bolted joint of the column,and the horizontal displacement load is applied to the top of the model column step by step,and the moment-rotation curve of the joint section is obtained.By changing the friction coefficient,pretightening force,splicing clearance and flange thickness of the model,the influence of the above factors on the mechanical performance of the model is studied.The results show that the greater the friction coefficient and the pretightening force,the greater the bending moment corresponding to the same deflection angle.The larger the stitching gap is,the larger the corresponding flection angle is when the model enters the plastic stage.The flange plate thickness has little effect on the constitutive relation of bending moment and flection angle,and the ultimate bearing capacity of the model increases slightly with the increase of flange plate thickness.The ExpDec1 function model is used to fit the discrete points of the above models,and the fitting results are good.The cyclic reciprocating horizontal displacement is loaded on the node model,and the hysteresis curve of the node bending moment and deflection angle are analyzed.The hysteretic curve of the model is relatively full,and the splicing method can absorb and consume the seismic energy very well.And has good plastic deformation ability.In addition,the friction coefficient,pretightening force and splicing clearance of the model are compared and analyzed.The results show that: In a certain range,the larger the friction coefficient and the pretightening force,the fuller the hysteretic curve of the model,the larger the energy dissipation coefficient E,and the better the energy dissipation performance of the column splicing joints.The splicing gap has little effect on the hysteretic curve of the model.The constitutive relation of force and displacement of semi-rigid steel frame with high-strength bolted joint of the column is studied,and the influence of splicing position on force and displacement of semi-rigid frame is analyzed.At the same time,the hysteretic behavior of semi-rigid frame is studied and compared with rigid steel frame.The results show that: Compared with rigid frame,semi-rigid frame has better energy dissipation capacity and plastic deformation ability.Finally,by comparing the hysteretic performance of semi-rigid frame models with different splicing positions,it can be seen that the splicing position of frame columns has a certain effect on the energy dissipation of steel frame structures.