| Fiber Reinforced Polymer/Plastic（FRP）has obvious advantages in building structural reinforcement due to its advantages of light weight,high strength and corrosion resistance.The most commonly used method is to paste FRP sheet on the outer surface of the reinforcement structure with epoxy resin for external reinforcement.Although this method is convenient for construction,it is easy to cause damage due to end stripping when the fiber stress level is still low,which reduces the utilization rate of tensile strength of FRP materials.In addition,the deformation of masonry wall under horizontal and vertical loads includes shear deformation,bending deformation and rotational deformation.However,the seismic strengthening of masonry structures usually only considers the shear performance of the inter-story wall under the action of horizontal seismic force,but pays little attention to the bending and rotational deformation of the inter-story wall caused by the earthquake overturning moment.This paper mainly conducts a series of research and analysis on the reinforcement scheme of brick masonry building reinforced with Glass FRP.The main research work and results are as follows:（1）on the basis of summarizing the existing methods of end anchorage measures,four different end anchoring GFRP-masonry specimens were designed and fabricated for single shear tensile test.Through the analysis of the GFRP with brick interface stripping process,interface bond slip curve,strain distribution on the GFRP,study four anchorage measures the working mechanism,the anchoring effect and applicability.The results show that the failure mode of all anchorage GFRP specimens is interface debonding.Compared with the specimens without anchorage,the ultimate bearing capacity of GFRP reinforced with carbon fiber fan-head nail anchorage,adhesive mechanical mixed anchorage,resin adhesive nail anchorage and bidirectional carbon fiber patch anchorage increased by 85.69%,88.34%,68.82% and50.09%,respectively.Anchoring limited the slippage to a certain extent,and the effect of bidirectional carbon fiber patch anchoring was the most significant,which reduced by 44.58%.（2）taking the 230 mm thick unreinforced masonry wall as the research object,two series of quasi-static tests of walls with an aspect ratio of 0.68 and an aspect ratio of 1.37 were designed,each series including a set of contrast walls and a set of reinforced walls.The effect of GFRP reinforcement and anchorage measures on masonry wall bending reinforcement was analyzed.Based on the experimental data,such as experimental phenomenon,hysteresis curve,skeleton curve,ductility and energy consumption index,the seismic performance of the test wall was analyzed.The test results show that the wall rotates obviously during the loading process.After GFRP reinforcement,the integrity of the wall is improved obviously,the participation degree of rotational deformation is increased,and its proportion in the total deformation is increased,which is manifested as the rigid rotation in the plane with two corners as the fulcrum.The horizontal bearing capacity of the wall strengthened with pure external GFRP is not significantly increased,and the positive and negative bearing capacity of the wall strengthened with adhesive and mechanical anchorage is increased by 28.07% and 21.66%,respectively,compared with that of the wall not strengthened.After reinforcement,the deformation capacity of the wall is enhanced and the ductility is obviously improved. |
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