Failure mechanism and optimization of fiber-reinforced polymer cable-anchor system based on 3D finite element model

Abstract In this study, a three-dimensional (3D) finite element (FE) model of multiple-tendon fiber-reinforced polymer (FRP) cable-anchor system (CAS) was established to reveal the stress and deformation of an FRP cable. The model was firstly validated by the previous experimental results. The failure mechanism of FRP cable was clarified through FE analysis. Three types of optimizations, including changing the spacing of the FRP tendons, conducting the radial variable stiffness of the load transfer component (LTC) and changing the inner cone form of the anchorage, were conducted to improve anchor behavior. For FRP tendons, the radial compressive stress, as well as the relative radial displacements, were found to be nearly identical at different positions. An evident uneven axial tensile stress was observed for both the intra- and inter-tendon scenarios, in which the maximum axial tensile stress occurred in the outermost layer tendon. The failure of the FRP cable was dominated by the excessive tension-bending stress and radial compressive stress at the loading end. Applying radial variable-stiffness LTC was found to be the most effective method, and was validated in different tendon diameters and number of tendons.