The Research Of Seismic Performance About High Performance Composite Mortar Reinforced By CFRP Net Strengthening Earthquake-damaged Frame Joints

Frame joints connect beams and columns,which is an important part of frame structure.During the earthquake,the joints suffered large shear failure,which resulted in the whole frame structure losing its integrity and causing the collapse.According to the investigation of earthquake damage to a building after a large earthquake,except for a small number of buildings that are severely damaged and unable to repair,most buildings are in light or severe damage,which can be repaired after identificating of damage level.At present,the research on seismic capacity of damaged frame joints is very limited.Therefore,there are great significances to study seismic strengthening of damaged joints.The high performance composite mortar reinforcement method reinforced by CFRP network combines the lightweight,high strength,high tensile strength and easy construction of CFRP network.The thickness of the reinforced layer will not obviously increase and the compatibility of high performance composite mortar with the reinforced structure is good.There is great research space,and the research on strengthening the joints with seismic damage is still in its infancy.In this paper,reinforced concrete frame joints with different seismic damage degrees are strengthened by CFRP net reinforced high performance composite mortar reinforcement.Study on the seismic performance of reinforcement.5 frame joints with a scale of 1:2 were made,and 3 of them were damaged to varying degrees.Through quasi-static test,numerical analysis and theoretical analysis,study the influence of different earthquake damage on the reinforcement.The main conclusions are as follows:1.CFRP net reinforced high-performance composite mortar reinforcement method is an effective reinforcement method.After strengthening,the bearing capacity,ductility,stiffness and energy dissipation capacity of the specimens are improved.The reinforced concrete frame joints transition from brittle failure to ductile failure.2.Effect of earthquake damage on the seismic performance of reinforcement.With the increase of earthquake damage,the accumulation of cracks inside the concrete increases,and the improvement of the seismic performance of the joints is smaller.3.The consolidation process is summarized.The construction technology of reinforcing joints with high performance composite mortar strengthened by CFRP net is summarized.4.ANSYS is used to do numerical simulation analysis of the specimen.Comparing test value and simulated value,they are in high degree of anastomosis.The reliability of the model is explained.This model can be used to predict the seismic performance of damaged damaged frame joints.5.Theoretical deduction of shear capacity formula of reinforced frame joints.Provide reference for follow-up researchers...