Cyclic Inelastic Deformation and Fatigue Resistance Characteristics of a Rail Steel

The cyclic inelastic deformation and fatigue resistance characteristics of a typical rail steel in use by American railroads have been determined. Uniaxial smooth specimens were obtained from the head of an unused section of rail and subjected to a variety of test conditions—static tension, static compression, and fully reversed constant-amplitude strain cycling. Additionally, a study of “history effects” was made. Included in this study were tests to examine the influence of orientation, mean stress, initial prestrain, and periodic overstrain, both the cyclic deformation response and the fatigue resistance being reported for each condition. Results obtained from these tests are discussed in light of predictive models for rail failure, particular attention being paid to the influence of stress state on deformation response and fatigue resistance.