Novel anchor system for CFRP rod: Finite-element and mathematical models

An innovative wedge-anchor system with a longitudinal circular profile has been designed for gripping carbon-fiber-reinforced-polymer rods. The anchor system, consisting of a barrel, a number of wedges, and a sleeve, is capable of carrying the ultimate tensile strength of the rod. Three-dimensional (3D) and axisymmetric finite-element models have been developed and applied in order to determine the stresses inside the anchor system. Using the 3D model, the overall performance of the anchor represented by the tensile load-displacement relationship compared favorably with the experimental results. A comparison study between the 3D and axisymmetric models revealed that the axisymmetric model underestimated the contact pressure on the rod surface. Using the force-fitting principle of thick cylinders, a mathematical model was also developed, and under specific assumptions, the mathematical solution compared favorably with finite-element model results.