Single and multiple impact behavior of CFRP cables under pretension

The vulnerable transverse behavior of the carbon-fiber-reinforced polymer/plastic (CFRP) restricts the application of CFRP cables in bridges, when considering the possible collisions from vehicles. This paper presents an experimental investigation on the transverse impact behavior of the CFRP cable system. Drop-weight impact tests were conducted on six specimens. Each specimen composed of a seven-wire CFRP strand and two reactive powder concrete (RPC)-grouted bond-type anchors at both ends. Test results showed that the RPC grouted bond-type anchor provided a reliable anchorage to the CFRP strand during both single and multiple impacts. For single impact of a specimen under a pretension of 40 kN, the average transverse impact resistance and energy dissipation capacity were approximately 16 kN and 727 J, respectively. The successive two impacts induced damage led to reductions of 37% in transverse resistance, 30% in maximum cable tension, 39% in transverse stiffness, 20% in energy dissipation capacity. A modified SDOF model based on nonlinear geometric stiffness and available impact energy was established for the prediction of the impact force and deflection of a CFRP cable under single and multiple impacts.