Experimental Investigations on Impact Behavior of CFRP Cables under Pretension

Carbon fiber-reinforced polymer/plastic (CFRP) used in bridge cables may be subjected to lateral impacts caused by vehicle collisions when in service. However, to date, few studies have been conducted on the impact behavior of CFRP cables and their anchor systems. In this paper, the impact behavior of CFRP cables was investigated through drop-weight tests of eight CFRP cable specimens. A seven-wire CFRP strand was used as the tendon, and reactive powder concrete (RPC) was used as the filling grout for anchors at both ends of each specimen. The results show that a bond length of no less than 36 times the diameter of the wire of the CFRP strand in 128 MPa RPC grout can provide a CFRP strand with reliable anchorage under impact. The average transverse impact resistance of the specimens was approximately 16 kN and was not significantly influenced by pretension. The specimens fractured at a cable tension of 30% of the static tensile breaking load under transverse impact. In addition, the energy dissipation capacities for specimens with pretension to static tensile breaking load ratios of approximately 10, 21, and 26% were 632, 727, and 902 J, respectively. Finally, a normalized energy profile diagram (EPD) was established for the design and damage evaluation of a CFRP cable in the case of an impact event.