Research On The Stress Of The Anchorage Zone Of The End Fixing Base Of Prestressed Carbon Fiberboard

In the prestressed carbon fiber sheet reinforcement system,the tensioned and anchored ends are the most important components,not only to bear the tensile force of the carbon fiber sheet when tensioned,but also to bear the increment of tensile force of the carbon fiber sheet during the use phase.All these forces must be The anchoring seat transmits to the concrete structure,so the stability of the anchoring area of the prestressed carbon fiber board determines the reliability of the prestressed carbon fiber board reinforcement technology.This paper studies the anchoring capacity and mechanical properties of the anchoring seats of prestressed carbon fiber plates.Firstly,the experimental study was conducted from the stress mechanism of single anchor bolts,and then the stress performance of multiple anchor bolts on the anchor seats was performed.Tests and numerical analysis were also conducted to explore the effect of bonding alone on the stress behavior of anchor seats.The following conclusions were obtained from these studies:(1)According to the experimental results of single anchor bolts,a theoretical simplified model for single anchor bolts is proposed.Although there are certain errors between the results of shear stress and finite element calculations calculated by this model,the trend is consistent.Reference calculation method as practical application.(2)Through comparative analysis of tests and finite element calculations,it can be concluded that the axial stress of a single anchor bolt increases at the same anchorage depth and the same load,and the axial stress of the anchor bolt gradually increases with the increase of the load.The shear stress of a single anchor bolt under the same load,the shear stress of the anchor bolt with different anchorage depth increases with the depth of the anchorage,and for the same anchor bolt,the shear stress increases with the load.Increase.For a single anchor bolt with a constant anchorage depth and an unchanged external load,the bending moment at the junction between the exposed part of the anchor bolt and the implanted part will decrease as the depth of the anchorage increases;for the same anchor For bolts,this bending moment will increase as the load increases.(3)During the entire loading test,the anchorage seat with multiple anchors was not found to be slippery.The stress and deformation of the anchor base plate were basically consistent with the finite element numerical simulation.The stress distribution was better than that of the old-fashioned end anchorage.The seat is more uniform and the anchor seat has a good mechanical performance.(4)Through the strain test and finite element analysis of multiple anchor bolts in a mid-support anchorage,the closer to the anchorage seat backstop in the same longitudinal section,the greater the anchor bolt force,and vice versa.Therefore,in the design of anchor bolt position distribution of the anchor seat,the force characteristics should be paid attention to.(5)The anchor base plate is bonded to the concrete,and the anchorage force provided by the bonding is an important part of the anchorage bearing capacity of the anchor seat.The anchor seats that only consider the bonding effect(the anchorage force is not taken into consideration,and the anchor anchor force is not considered)are subjected to force.Performance tests and numerical simulations.The study shows that the stress and deformation of the anchor plate are gradually increased with the increase of tension force,which is consistent with the finite element calculation simulation results.The test results show that the bearing capacity of the anchor seat only considering the adhesion can reach about 70 kN,and the adhesion effect should be given full consideration in the calculation of the anchorage force of the anchor seat and the force analysis,and can not be ignored.