A prediction model for hydrogen induced cracking in a prestressed wire with a fracture analysis

Abstract

This paper deals with the Hydrogen Induced Cracking (HIC) behavior of high strength tendon wires of a prestressed structure, exposed to aggressive environments. A decoupling technique has been suggested to evaluate crack propagations in a wire section, driven by the hydrogen diffusion. By the proposed decoupling technique, three dimensional crack propagations can be modeled effectively by two 2-dimensional finite element models, one for the fracture analysis of a round bar wire in a longitudinal section, and the other for a hydrogen diffusion model in a horizontal section. Elastic and bi-linear elastic-plastic finite element analyses have been carried out for the evaluation of crack propagations in wires of tendon. A finite element program is developed for the hydrogen diffusion-stress analyses of wires. The decoupled analysis results have been compared with available test results, and showed improved results than the linearly assumed analytical equations suggested by Forman et al.