Abstract:
In order to study the bond behavior between glass fiber reinforced polymer (GFRP) bars and self compacting concrete (SCC), pull-out tests on sixty-six GFRP/SCC specimens were deployed and carried out. The effects of SCC cover thickness, bond length and diameter of GFRP bars as well as the fiber types added to SCC on bond properties were investigated. In addition, the failure modes of specimens were analyzed. The results show that there are mainly three failure modes, namely splitting failure, pull-out failure and pull-out failure with cracks. It is found by scanning electron microscopy (SEM) that the infilling direction of SCC has a certain influence on the structure of the bar-SCC interface. The upper interface of GFRP bars is bonded more closely to SCC compared with the lower one. When the SCC cover thickness increases from 4
D to 7
D, the bond strength is increased by about 44.05%. When the bond length of GFRP bars increases from 5
D to 15
D, the bond strength decreases by about 65.43%. When the diameter of GFRP bars increases from 12 mm to 16 mm, the bond strength decreases by about 22.57%. Meanwhile, the bond strengths of the specimens mixed with polypropylene fiber, steel fiber, hybrid fiber (polypropylene fiber and steel fiber) in SCC are about 12.80%, 15.16%, 15.09% higher than that of the specimens without any fibers respectively. Hence, the bond strength of GFRP/SCC specimens can be improved by increasing the SCC cover thickness, or adding fibers to SCC etc.