Bond durability of basalt-fiber-reinforced-polymer bars embedded in lightweight aggregate concrete subjected to freeze-thaw cycles

In recent years, basalt-fiber-reinforced-polymer (BFRP) bars have become popular to replace steels. However, little is known about the performance of BFRP bars inserted in lightweight aggregate concrete (LWAC), especially the bonding performance under freeze-thaw (FT) cycles. In this study, a bond strength test was conducted for BFRP bars embedded in LWAC after FT cycles. BFRP bars, epoxy-coated bars, and steels were tested for comparison purposes. The test parameters are the bar type, compressive strength of the LWAC, and FT cycles; 108 specimens were subjected to 0, 15, 30, and 50 FT cycles. Moreover, the bond strength models of the three types of bars were fitted to LWAC. The test results prove that the number of FT cycles significantly affects the bonding performance of the bar embedded in LWAC. The results also show that the bond strength prediction of the fitting model considering the FT cycle effect is consistent with the experimental results.