Reliability assessment of fiber-reinforced polymer cable-anchorage system

Abstract

In this study, an evaluation framework for the reliability of a fiber-reinforced polymer (FRP) cable-anchorage system was established. We first developed a simplified 3D finite element (FE) model for an effective FRP cable anchorage, in which layers of FRP tendons were equivalent to several concentric rings. The performance of the anchorage system was evaluated using the maximum Tsai–Wu failure index (FImax) of all cable elements. By feeding 1600 samples generated from the above FE model, a back-propagation neural network (BPNN) was trained to rapidly predict FImax. Assuming that the overall failure was controlled by the weakest part, the reliability index β of the entire system can be calculated from FImax through a Monte Carlo (MC) simulation. The β of the prototype anchorage system reached 4.3635. Under a deterministic design load Fd, giving a target reliability index βT = 3.7, the design-to-ultimate ratio was estimated to be 0.532. The sensitivity analysis suggested that the FImax was most sensitive to the longitudinal tensile strength of the FRP cable and the thickness of the load transfer component (LTC, also known as load transfer medium or LTM) at the loading end.