ENVIRONMENT ALLY-ASSISTED FATIGUE CRACK GROWTH IN PRESTRESSING STEEL WIRES

摘要

We present the evolution of the surface crack front in prestressing reinforced-concrete steel wires subjected to fatigue in air and to corrosion fatigue in Ca(OH)_2 + NaCl. To this end, a numerical modeling was performed on the basis of discretization of the crack front (with elliptic shape) by considering that the crack advance at each point is perpendicular to the analyzed front according to the Paris-Erdogan law and using a three-parameter solution for the stress intensity factor (SIF). Each analyzed case (a particular geometry of the initial crack) was characterized by the evolution of the aspect ratio of the semiel-liptic crack (ratio of the semiaxes of the ellipse) with the relative crack depth and by the variations of the maximum dimensionless SIF at the crack front.