A Study on the Bond–Slip Relationship of the CFRP–Steel Interface of CFRP Strengthened Steel

Abstract

The bonding interface between the CFRP and the steel plate is the weak link of CFRP-strengthened steel structures. This paper studies the bond–slip relationship of the CFRP–steel interface by experiments and numerical tests. First, a series of double-strap experiments on a CFRP-strengthened steel plate are carried out. The results show that the maximum shear stress of the bonding interface of the Q345B specimen is larger than that of the X100 specimen. The initial slip and maximum slip become larger as the thickness of the bonding interface becomes larger. Finite element analysis of the above tests is carried out; we introduce the maximum stress criterion to simulate the bonding interface, which assumes that when the nominal stress of the material reaches the maximum nominal stress of damage, the material begins to damage. The FE model established has proved very effective for analyzing the bond characteristics of CFRP-strengthened steel plates. Finally, a verification test was carried out, using an FE analysis to verify the accuracy of the modified equations; the results prove that the results of the modified equations are in good agreement with the numerical results and experiment results, which verifies the effectiveness of the equations.

Study on Flexural Behavior of Corroded I-Shaped Steel Beams Strengthened with Hybrid CFRP/GFRP Sheets

“…GFRP and CFRP exhibit various anisotropy as composite materials. The modulus and stress of hybrid materials comply with linear mixing laws, proving that CFRP and GFRP conform to the principle of equal strain during the stress process of hybrid materials [21][22][23][24], and the stress-strain relationship is linear [25][26][27][28][29][30]. The material parameters are set according to the testing report in Section 2.2 of this article.…”

Fatigue performance of carbon fiber‐reinforced polymer strengthened single‐edge cracked steel plates: Effects of adhesive property and CFRP arrangement

“…In addition, as the bond length extends, the interfacial ultimate load increases until the effective bond length is reached. As the thickness of the bonding interface becomes larger, the initial slip and maximum slip become larger, and the interfacial ultimate load increases 20,21 . Hu et al 22 discovered that crack‐induced debonding is proportional to crack length by examining the strain gradient of CFRP by a series of experiments study on center‐cracked steel plate under fatigue loading.…”

“…As the thickness of the bonding interface becomes larger, the initial slip and maximum slip become larger, and the interfacial ultimate load increases. 20,21 Hu et al 22 discovered that crack-induced debonding is proportional to crack length by examining the strain gradient of CFRP by a series of experiments study on centercracked steel plate under fatigue loading. However, there is limited research on interfacial failure characteristics of CFRP-strengthened single-edge cracked steel plates under fatigue loading.…”