Experimental Study On Seismic Performance Of Masonry Structure Reinforced With External Prestressed Inclined Tie Rod

In recent years,the our country is a seismic country building is the worst affected by the earthquake damage masonry structure building,to the people’s life and property security caused great losses,so the seismic strengthening of existing buildings masonry structure transformation has a very practical research significance,this paper put forward the masonry structure with prestressed inclined rod seismic strengthening technology.The main work and conclusions of this paper are as follows:(1)Three full-scale brick masonry walls were tested before and after the reinforcement,and the reinforcement effects of prestressed inclined tie rods were analyzed.The results show that the walls with direct and indirect reinforcement of prestressed inclined tie rods are significantly better than those without reinforcement in terms of shear capacity,ultimate displacement,ductility,energy consumption,stiffness degradation and other seismic properties.(2)The whole-process nonlinear finite element simulation analysis of the test wall is carried out,and the load-displacement skeleton curve obtained from the simulation is in good agreement with the test.According to the equivalent stress,equivalent plastic strain and other cloud images,it can be seen that the failure pattern is consistent with the test failure process.Furthermore,the parametric analysis of the directly reinforced wall is carried out.Based on the standard formula,the proposed formula for the shear capacity of the directly reinforced masonry structure with prestressed inclined tie rods is proposed.(3)Directly before and after the reinforcement of two layers of masonry buildings whole model for the dynamic elastic-plastic time history analysis,the results show that under the 8 degrees to flame,X direction maximum interlayer displacement Angle of1/147 and 1/307 respectively before and after reinforcement,the maximum displacement between layers after reinforcement unreinforced decreased by 52%,to satisfy the whole model after reinforcement is not "big" fortification goal.It can be seen from the equivalent stress cloud diagram that the prestressed inclined tie bar improves the stress state of the whole building,and the stress of the strengthened wall is uniform,which delays the development of shear cracks,and effectively reduces the stress concentration of the corner constructional column.The new reinforcement technology not only provides theoretical guidance and scientific basis for the development of prestressed inclined ties,but also highlights the advantages of simple construction procedure,short construction period,low noise,low cost,and no reduction of the usable area of the house.It is a new seismic reinforcement technology for existing buildings worthy of promotion.