Growth of the shell/transverse defect in rails

An approximate analysis of the shell/transverse defect growth in steel rails during use is presented. A general solution for a single subsurface crack is presented first. A simpler approach, which considers the transverse defect alone, is examined as well. Residual stresses are included by introducing their stress distributions mechanically. A proposed mixed-mode loading growth law is used for fatigue life calculations and the crack length versus life curves are obtained. The life of the shell/transverse defect is found to be much shorter than that of the single transverse defect.