Lap-splicing of GFRP bars under compression

Fibre reinforcement polymer (FRP) bars have been extensively investigated as a promising substitute for conventional steel reinforcement in reinforced concrete (RC) structures imposed to corrosive environments. Nowadays, many FRP RC structures are being constructed in areas where corrosion is a deteriorating concern. Among different applications, FRP reinforcement may be also used in compression members. Although it is inevitable in real constructions, compression lab splicing of FRP bars has not yet been explored in details. Consequently, this research was aimed at investigating the effect of splice length on strength of lap-spliced glass FRP (GFRP) bars under compression. The experimental program was comprised of five circular RC columns. Among them; one specimen was reinforced with steel bars and the rest with GFRP bars. The steel specimen was reinforced with continuous bars and used for comparison purposes. All column specimens measured 300 mm in diameter and 1600 mm in length. The reinforcement details of all specimens were identical and the only differences were reinforced type and splice length. The tests were conducted under a monotonically increasing concentric load. During the test, the applied load versus the longitudinal displacement and ultimate displacement capacity. The results were discussed in terms of the failure modes, compressive strength, and ultimate displacement capacity.