Abstract

This study is an experimental investigation of the bond stress–slip behavior of BFRP bars in recycled coarse aggregate concrete using the pull-out experiment. The experimental program contains twenty-three BFRP specimens and twelve specimens with GFRP bars. The pull-out test results of the BFRP and GFRP specimens in recycled coarse aggregate concrete are balanced to those of normal coarse aggregate concrete, which are used as a benchmark. In this study, the influence of major parameters on the BFRP bond performance are investigated: concrete strengths (30, 45, and 60 MPa), bar diameter (8, 10, and 12 mm), and bar bond length (5, 10, and 15d, where d is the diameter of the bar). The effect of the parameters considered is determined on the basis of the increase in the bond resistance. The test findings showed that the bond resistance of BFRP bars in recycled coarse aggregate concrete is highly comparable to that of normal aggregate concrete. In addition, the BFRP bar pull-out failure is not governing when a bar bond length of 10 or 15d, or high concrete strength of 45 or 60 MPa, is utilized. Theoretical equations from the literature that predict the bond resistance and bond stress–slip performance for FRP reinforced concrete are compared to the experimental results of this study. It is found that the equation described by Orangun and colleagues can accurately predict the bond resistance for BFRP bars in recycled coarse aggregate concrete with an average of 86% compared to the experimental results.

Highlights

  • Received: 22 November 2021Basalt fiber reinforced polymer (BFRP) is a fairly new concept to FRP and composites.Recently, BFRP bars emerged as an option to replace glass FRP (GFRP) bars in reinforced concrete

  • According to the few studies available investigating the bond performance of GFRP and BFRP bars in recycled coarse aggregate concrete, the current experimental investigation aims to enrich the database of BFRP bar bond performance in recycled coarse aggregate concrete that can expand the life service of structures and reduce their cost of rehabilitation or replacement

  • This study endeavors to determine the performance of the BFRP bars in recycled coarse aggregate concrete using the direct pull-out test, which is scarcely examined in the available literature

Read more

Summary

Introduction

Basalt fiber reinforced polymer (BFRP) is a fairly new concept to FRP and composites. El Refai and colleagues [27] investigated the bond performance of BFRP bars in high concrete compressive strength using the direct pull-out test. Shen and colleagues [28] conducted pull-out tests to examine the relationship between the BFRP bar diameter and concrete strength. The bond performance of BFRP bars exposed to the effects of freeze-thaw cycles (FT) was examined by Khanfour and El Refai [38] Their pull-out test results showed that the FT cycles had a slight effect on the bond resistance. Two studies have examined the pull-out performance of GFRP bars [49] and BFRP bars [50] in concrete made of recycled coarse aggregates. According to the few studies available investigating the bond performance of GFRP and BFRP bars in recycled coarse aggregate concrete, the current experimental investigation aims to enrich the database of BFRP bar bond performance in recycled coarse aggregate concrete that can expand the life service of structures and reduce their cost of rehabilitation or replacement

Research Objectives
Material Specifications
Specimens Tested
Test Setup
Experimental Results and Discussions
Bond Stress–Slip Relationships
Failure Modes
Strength of Concrete
Bond Length
BFRP Bar Diameter
FRP Elastic Modulus
Bond Energy
Theoretical Predictions
Bond Resistance
Bond Stress–Slip Analytical Approaches
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call