Behavior of Concrete Piles Confined with CFRP Grid

Synopsis: This paper describes an experimental program undertaken to study the behavior and effectiveness of using Carbon Fiber Reinforced Polymer(CFRP)Grid, as an alternative for steel spirals to confine precast concrete piles. The research focuses on the effectiveness of the confinement of the specified C-Grid on the concrete core of piles. The experimental program consists of a total of seven short piles including one without confinement, two with steel spiral and four with C-Grid. The parameters included in the study were the number of grid layers, the overlap length, and the spacing between the circumferential wires of C-Grid. All the specimens were subjected to concentric axial compression up to failure. Results indicate that the specified C-Grid can provide equivalent performance or more than typical spiral steel reinforcement for precast prestressed concrete piles. The paper also presents an analytical model to predict the performance of piles reinforced with C-Grid as spiral reinforcement. The analytical model yields results that match well with the experimental results.