Work

Bond characteristics of GFRP and BFRP bars embedded in Self-Compacting Concrete with different substitutes

Year: 2026

Type: article

Abstract: This study investigates the bond behavior of GFRP, BFRP, and steel bars in Self-Compacting Concrete (SCC) with and without cement replacements. Three specific SCC mixtures were developed: a control batch using only Portland Cement (PC), one utilizing Fly Ash (FA) as a partial PC replacement, and a third containing Granulated Blast Furnace Slag (GBFS). In total, 36 distinct hinged beam specimens featuring a constant embedment length were tested at 28 and 90 days after casting. The actual experimental bond stresses at failure were compared against analytical bond strength estimates derived from international codes and prior literature. The extensive testing demonstrated that BFRP bars achieve bond performance and strength levels directly comparable to traditional steel reinforcing bars. In contrast, GFRP bars showed consistently lower bond performance compared to both BFRP and steel. Furthermore, existing code equations failed to predict the experimental behavior accurately. They produced estimates that were 1.5 to 2 times larger than experimental values for BFRP bars, and yielded estimates between 0.6 and 1.15 times the actual values for GFRP bars. Conversely, the equations previously proposed by the authors provided highly consistent estimates, predicting bond stress safely within 0.55 to 0.70 times the experimental results.

Source: Journal of Asian Architecture and Building Engineering

DOI: 10.1080/13467581.2026.2740907