Mechanical Performance Analysis Of High Strength Friction Bolt Joint Plate

The steel structure construction period is short,light weight,large capacity,easy component characteristics across the repair and replacement in the construction of universal application,China's steel bridge adopts friction type high strength bolt connection of the rod bolt,putting pressure on the gusset plate and bar the contact load between the surface and the rod through the contact node transfer plate.When the bolt breaks off on the steel bridge plate,the bolt breaking and falling off will affect the safety of the driving and the bearing performance of the bridge to some extent.According to the research on bridge linked nodes to carry out the work of bolt off problem,the main work:analysis of the distribution of equivalent friction distribution and node gusset plate surface under wind load stress,friction plate node distribution on the surface under the action of gusset plate by torsion.The influence of two factors such as friction coefficient and bolt pretightening force on the force of the joint plate and the effect of the loss of bolt on the force ratio of each column bolt on the plate are analyzed.The main results are as follows:(1)under axial force,friction plate node distribution is around the big middle small;under torsion,large friction plate of the regional node corner position on the surface of the friction surface of the small area of the center position;in the bolt preload and external load,node plate stress distribution is not uniform and the equivalent stress decreases gradually from the hole position to around.(2)the friction coefficient will affect the distribution of friction joint plate surface,when the friction coefficient decreases,friction distribution node plate surface is more uniform;in two cases the actual load transfer path:one is through the friction plate and rod node transmission between two nodes,through the bolt and the bolt and the friction plate and rod a transfer between.(3)the column head bolt pretightening force change on the node plate bearing the greatest impact,reduce the column head bolt pretightening force,friction force distribution of gusset plate surface is relatively more uniform;bolt pretightening force lower than the increase of the pre tightening force of friction effect on node plate surface is bigger;the missing bolt will lead to joint plate the rest of the column bolt force transmission ratio increases,is not conducive to the node plate stress.