The Shear Performance Of Concrete Beam Strengthened With Near-surface Mounted (NSM) FRP Reinforcement

In recent years,the concrete structure strengthened with near-surface mounted(NSM)FRP reinforcement is a new strengthening methods.The FRP materials with light weight,high strength,corrosion resistance,good fatigue resistance,the strengthened it is widely used in the engineering.At present,the strengthening methods are NSM and externally bonded(EB),The use of NSM FRP reinforcement is still in its infancy,especially the shear strengthening method.The Seventeen beams(2 control beams,15 strengthening beam)were analyzed with finite element software abaqus to study the shear performance.The finite element simulation results were compared with the test results,to verify the reliability of the finite element simulation.The parameters of shear span ratio,FRP spacing,embedded angle,types of FRP,concrete strength were used to analysis the shear stress performance,The ultimate bearing capacity,stiffness,stirrup and FRP slab strain of reinforced beams were analyzed,combining with the finite element simulation analysis of FRP batten in the calculation method of effective strain in the reinforcement process.The arch-truss model is derive the formula to calculate the shearing resistance.The finite element simulation results are in good agreement with those obtained with the test results,The strengthened with NSM FRP can significantly improve the shear capacity of the beam,The shear ratio is the key factors influencing the shear bearing capacity.In the case of other conditions unchanged,The shear span ratio,the greater the reinforced beam and the smaller the ultimate bearing capacity,The smaller the FRP slab spacing is,the higher the ultimate bearing capacity,FRP slat 45 ° patch angle than 90 ° sticking angle is more superior,The effect of CFRP and GFRP on the ultimate bearing capacity of reinforced beams is not obvious,The higher the strengthof concrete,the more conducive to the FRP slats to play,the shear mechanism of the FRP is similar with stirrup.