As an important component,the bond behavior of carbon fiber-reinforced polymer(CFRP)-concrete interface for a reinforced concrete(RC)beam is very significant.In this study,a theoretical model was established to analyz...As an important component,the bond behavior of carbon fiber-reinforced polymer(CFRP)-concrete interface for a reinforced concrete(RC)beam is very significant.In this study,a theoretical model was established to analyze the flexural behavior of CFRP-strengthened RC beams,and the CFRP-concrete interfacial bond-slip relationship under hygrothermal environment was unified into one model.Two failure criteria corresponding to two types of failure modes,i.e.,concrete crushing and intermediate crack(IC)-induced debonding,were developed.Through the theoretical model,the flexural behavior of deflection,interfacial shear stress distribution and ultimate load of a CFRP-strengthened RC beam under hygrothermal environment were obtained and predicted.Moreover,the theoretical model was verified by test results.The results showed that the hygrothermal environment had a significant impact on the CFRP-concrete interface behavior.Compared with the control beam without hygrothermal environment pretreatment,the deflection and ultimate load of the strengthened RC beam decreased by 51.9%and 20%,respectively.展开更多
The application of prestressed carbon reinforced polymer （prestressed CFRP） in reinforced concrete （RC） members can improve the mechanical properties of strengthened structures and strengthening efficiency. This p...The application of prestressed carbon reinforced polymer （prestressed CFRP） in reinforced concrete （RC） members can improve the mechanical properties of strengthened structures and strengthening efficiency. This paper proposed a semi-empirical prediction fornmla of fatigue lives of the RC beams strengthened with prestressed CFRP under bending loads. The formula is established based on the fatigue life prediction method of RC beams and fatigue experimental data of non-prestressed CFRP reinforced beams done before. Fatigue effect coefficient of the formula was confirmed by the fatigue experiments of the RC beams strengthened with prestressed carbon fiber laminate （prestressed CFL） under cyclic bending loads. Fatigue lives of the strengthened beams predicted using the formula agreed well with the experimental data.展开更多
基金The authors would like to acknowledge the financial support from the National Natural Science Foundation of China(Nos.11872185,11627802,51678249,11132004)the Natural Science Foundation of Guangdong Province(No.2019A1515012222).
文摘As an important component,the bond behavior of carbon fiber-reinforced polymer(CFRP)-concrete interface for a reinforced concrete(RC)beam is very significant.In this study,a theoretical model was established to analyze the flexural behavior of CFRP-strengthened RC beams,and the CFRP-concrete interfacial bond-slip relationship under hygrothermal environment was unified into one model.Two failure criteria corresponding to two types of failure modes,i.e.,concrete crushing and intermediate crack(IC)-induced debonding,were developed.Through the theoretical model,the flexural behavior of deflection,interfacial shear stress distribution and ultimate load of a CFRP-strengthened RC beam under hygrothermal environment were obtained and predicted.Moreover,the theoretical model was verified by test results.The results showed that the hygrothermal environment had a significant impact on the CFRP-concrete interface behavior.Compared with the control beam without hygrothermal environment pretreatment,the deflection and ultimate load of the strengthened RC beam decreased by 51.9%and 20%,respectively.
基金Project supported by the National Natural Science Foundation of China (Nos. 11132004 and 51078145)the Guangdong Province Natural Science Foundation of China (No. 9251064101000016)
文摘The application of prestressed carbon reinforced polymer （prestressed CFRP） in reinforced concrete （RC） members can improve the mechanical properties of strengthened structures and strengthening efficiency. This paper proposed a semi-empirical prediction fornmla of fatigue lives of the RC beams strengthened with prestressed CFRP under bending loads. The formula is established based on the fatigue life prediction method of RC beams and fatigue experimental data of non-prestressed CFRP reinforced beams done before. Fatigue effect coefficient of the formula was confirmed by the fatigue experiments of the RC beams strengthened with prestressed carbon fiber laminate （prestressed CFL） under cyclic bending loads. Fatigue lives of the strengthened beams predicted using the formula agreed well with the experimental data.
