Fatigue behavior of rope wires

The dynamic behavior of rope wires can be estimated by help of rotary bending tests as well as by tension-tension tests. In rotary bending tests the amplitude stress is freely adjustable. The mean stress is set to always be zero. In tension-tension tests the amplitude stress as well as the mean stress can be adjusted to any desired level. For a common evaluation of all tension-tension tests amplitude and mean stresses should be substituted by an equivalent amplitude stress and a mean stress of zero, which lead to the same fatigue life as the combination of amplitude and mean stresses. Various models exist to calculate the equivalent amplitude stress. These so called mean stress correction models describe the influence of the mean stress. In the following, two suitable models will be presented which allow a common evaluation of all tension tension tests and also a common description of rope wire fatigue behavior.

Author: U. Briem