Title: Bond Behavior of Glass Fiber-Reinforced Polymer Bars Under Long Term Thermal Conditioning

Author(s): Jahanzaib, Shamim A. Sheikh, and Husham Almansour

Publication: Structural Journal

Volume: 119

Issue: 5

Appears on pages(s): 153-166

Keywords:

DOI: 10.14359/51734800

Date: 9/1/2022

Abstract:
The bond strength of glass fiber-reinforced polymer (GFRP) reinforcing bars after long-term thermal conditioning was experimentally investigated in this study. The results of 23 pullout and 14 beam specimens constructed with 16 mm sand-coated GFRP bars are presented. To study the long-term durability of the bond of GFRP bars with concrete, specimens were conditioned at 50 and 80°C for 4 months under a relative humidity of 60%. The pullout specimens were tested under direct tensile load and the beam specimens were tested under four-point loading. Variables in the study included concrete compressive strength, embedment length, test type, and temperature. Based on the experimental results, it was concluded that the studied thermal conditioning induced up to 26% reductions in the bond strength of GFRP bars. Moreover, the beam specimens yielded lower bond stresses at room temperature and experienced more thermal degradation than their counterpart pullout specimens. The 50°C thermal treatment was designed to study the climate challenges of continuously increasing temperatures, and the 80°C thermal exposure was devised to replicate the elevated service temperatures that may result from extreme events such as fires.