Evaluation of the bond-dependent factors for CFRP bars used as structural reinforcement: A critical review

• Published in: Case Studies in Construction Materials 2023-07, Vol.18, p.e02064, Article e02064
• Main Authors: Bakar, Mohd Basri Che, Rashid, Raizal Saifulnaz Muhammad, Amran, Mugahed, Jaafar, Mohd Saleh
• Format: Article
• Language: English
• Subjects: Bond behavior; Bond strength prediction; Bond stress-slip; CFRP bars; Pullout test
• ISSN: 2214-5095; 2214-5095
• DOI: 10.1016/j.cscm.2023.e02064

This study analyzes the precious data from the literature on bond strength between concrete and CFRP bars associated with the pullout test. In this regard, an overview of the pullout test and bond stress-slip model, along with a systematic analysis of characteristic bond strength behavior, were reviewed extensively. Over 273 specimens of CFRP bar involved in pullout tests were mined from the experimental works reported by preceding researchers worldwide. Significant findings revealed that the pullout test is a widely used method for determining the bond strength of embedded CFRP bars in concrete. The concrete compressive strength, bar diameter, modulus of elasticity, embedment length and surface treatment all have a major impact on bond performance. Moreover, the development of an analytical model for bond stress-slip is paramount to present the interaction behavior as well as to perform numerical analysis. In addition, bond strength predictions by international guidelines are conservative. However, the bond strength calculated by ACI 440.1R-15 has proven to be more practical across all the statistical measures. In line with this review, recommended research areas are also successfully discussed and proposed for further investigation. •CFRP bars have been applied as structural reinforcement to develop such smart and sustainable RC structures.•Bond characteristics between CFRP bars and concrete are vital for composite action in RC structures.•A comprehensive review on the existing bond stress-slip models were evaluated.•Specific factors were found to have significant influence on the characteristic bond behavior of CFRP bars.•Further efforts are required to examine the bond behavior of CFRP bar with additional anchorage system.