Based on the Canadian Standards Association (CSA) criteria,105 pullout specimens were tested to investigate the effect of different rib geometries on bond strength of glass fiber reinforced polymer (GFRP) rebars embed...Based on the Canadian Standards Association (CSA) criteria,105 pullout specimens were tested to investigate the effect of different rib geometries on bond strength of glass fiber reinforced polymer (GFRP) rebars embedded in concrete. Two kinds of conventional reinforcing rebars were also studied for comparison. Each rebar was embedded in a 150 mm concrete cube,with the embedded length being four times the rebar diameter. The experimental parameters were the rebar type,rebar component,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Theoretical analysis was also carried out to explain the experimental phenomena and results. The experimental and theoretical results indicated that the bond strength of GFRP rebars was about 13%~35% lower than that of steel rebars. The bond strength and bond-slip behavior of the specially machined rebars varied with the rebar type,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Using the results,design recom-mendations were made concerning optimum rib geometries of GFRP ribbed rebars with superior bond-slip characteristics,which concluded that the optimal rib spacing of ribbed rebars is the same as the rebar diameter,and that the optimal rib height is 6% of the rebar diameter.展开更多
The reinforcement corrosion is the pitting corrosion of chloride corrosion.Hence,in this study,the variations of reinforcement tensile strength due to stress concentration of pitting corrosion are analyzed.The stress ...The reinforcement corrosion is the pitting corrosion of chloride corrosion.Hence,in this study,the variations of reinforcement tensile strength due to stress concentration of pitting corrosion are analyzed.The stress concentration consequence of corrosion on the reinforcement tensile capacity is studied utilizing tension tests and creating different ABAQUS software models.According to the modelling in various corrosion depths,strength reduction is less than 5%in corrosion with pit radius to reinforcement diameter ratio up to 0.3 and for corrosions higher than 0.4,the measure of capacity reduction is increased more to 30%.展开更多
Fiber reinforced plastics (i. e. FRP) rebars are one kind of high-performance composite materi- als used in concrete structures of civil engineering. Compared with ordinary steel rebars, FRP rebars have the characteri...Fiber reinforced plastics (i. e. FRP) rebars are one kind of high-performance composite materi- als used in concrete structures of civil engineering. Compared with ordinary steel rebars, FRP rebars have the characteristics of high tensile strength, an- tisepsis, light weight, low elastics modulus and low shear strength, et al. At present time, FRP re- bars have been studied and applied in Europe, America and Japan Since 2000, in the Fund of NS- FC, we systematically carried out experimental and theoretical studies on FRP rebars The progress of our research is briefly introduced in this paper.展开更多
基金Project (No. 200431882021) supported by the Western Communi-cation Construction and Science & Technological Project,China
文摘Based on the Canadian Standards Association (CSA) criteria,105 pullout specimens were tested to investigate the effect of different rib geometries on bond strength of glass fiber reinforced polymer (GFRP) rebars embedded in concrete. Two kinds of conventional reinforcing rebars were also studied for comparison. Each rebar was embedded in a 150 mm concrete cube,with the embedded length being four times the rebar diameter. The experimental parameters were the rebar type,rebar component,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Theoretical analysis was also carried out to explain the experimental phenomena and results. The experimental and theoretical results indicated that the bond strength of GFRP rebars was about 13%~35% lower than that of steel rebars. The bond strength and bond-slip behavior of the specially machined rebars varied with the rebar type,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Using the results,design recom-mendations were made concerning optimum rib geometries of GFRP ribbed rebars with superior bond-slip characteristics,which concluded that the optimal rib spacing of ribbed rebars is the same as the rebar diameter,and that the optimal rib height is 6% of the rebar diameter.
文摘The reinforcement corrosion is the pitting corrosion of chloride corrosion.Hence,in this study,the variations of reinforcement tensile strength due to stress concentration of pitting corrosion are analyzed.The stress concentration consequence of corrosion on the reinforcement tensile capacity is studied utilizing tension tests and creating different ABAQUS software models.According to the modelling in various corrosion depths,strength reduction is less than 5%in corrosion with pit radius to reinforcement diameter ratio up to 0.3 and for corrosions higher than 0.4,the measure of capacity reduction is increased more to 30%.
基金Support for this research by the Fund of Rising-Star Plan of Shanghai Scientific and Technical Committee(No.02QF14047)the Fund of National Natural Science Foundation of China(No.50008012)is gratefully acknowledged.
文摘Fiber reinforced plastics (i. e. FRP) rebars are one kind of high-performance composite materi- als used in concrete structures of civil engineering. Compared with ordinary steel rebars, FRP rebars have the characteristics of high tensile strength, an- tisepsis, light weight, low elastics modulus and low shear strength, et al. At present time, FRP re- bars have been studied and applied in Europe, America and Japan Since 2000, in the Fund of NS- FC, we systematically carried out experimental and theoretical studies on FRP rebars The progress of our research is briefly introduced in this paper.