Statistical modeling and reliability analysis of large-scale multi-tendon fiber-reinforced polymer cables

In this study, the classic fiber bundle model is exploited in the statistical modeling of fiber-reinforced polymer (FRP) cables. Important features of large-scale multi-tendon FRP cable are considered including initial random slack, uneven tensile deformation among tendons, and other statistical mechanical properties of tendon. Aiming at the prediction of load-displacement relation and design of thousand-meter-scale FRP cables, a parametric study and reliability analysis are conducted, in which the relation of reliability index beta of cable and safety factor gamma of FRP material is emphasized. In four different types of FRP cables from previous studies, the simulated loaddisplacement curves are in good agreement with experimental ones. The random slack and non-uniform deformation of tendons are found to have significant impacts on cable capacity. For a 10,000 m-long cable, compared to the original strength of the tendon, the retention rate of strength in real FRP cable can vary from 0.26 to 0.82, depending on the scattering of tendon strength. The recommended gamma is 3.0, 3.2, and 3.4 for target reliability index beta T = 3.7, 4.2, and 4.7, respectively. Then, the limits of design parameters for large-scale FRP cables are calculated under a given reliability index.

Automated summary

In this study, the statistical modeling of fiber-reinforced polymer (FRP) cables using the classic fiber bundle model is explored. The study considers important features of large-scale multi-tendon FRP cables, such as initial random slack and uneven tensile deformation among tendons. A parametric study and reliability analysis are conducted to predict the load-displacement relation and design thousand-meter-scale FRP cables. The study emphasizes the relation between the reliability index beta of the cable and the safety factor gamma of the FRP material.