An analysis of flexural bond length and anchorage length of prestressed fiber reinforced polymer reinforcement

Abstract

The main aim of this paper is to provide a broader analysis of the flexural bond length and anchorage length of different types of prestressed Fiber Reinforced Polymer (FRP) reinforcement and to provide corrections to the existing theoretical models. Therefore, this paper presents a description of the main parameters that influence the flexural bond length and anchorage length of different types of FRP reinforcement based on experimental results found in the literature. The database of more than 70 specimens was compiled with the results of the transfer length, flexural bond length, and anchorage length of FRP reinforcement and the main influencing parameters. The analysis of a larger database of flexural bond length revealed that propositions of coefficients αfb = 2.8 and αfb = 1.0 found in the literature for Carbon Fiber Composite Cable (CFCC) strands and Carbon Fiber Reinforced Polymer (CFRP) bars, respectively, should be corrected. Therefore, corrected values of coefficient αfb are proposed in this article for CFCC strands (αfb = 3.0) and CFRP bars (αfb = 0.9). Additionally, the new value of αfb = 1.4 is proposed for flexural bond length of Aramid Fiber Reinforced Polymer (AFRP) bars. Moreover, the main existing theoretical models are presented, and the comparison of theoretical and experimental flexural bond length and anchorage length results is discussed. Additionally, the analysis of the flexural bond length and anchorage length and the proposed new values of the coefficient αfb provides possibilities for adapting it to design codes for engineering applications and performing additional research that fills the missing gaps in the field.