Analytic Methods for Estimating the Effects of Stochastic Intermittent Loading on Fatigue-Crack Nucleation

Abstract

The Palmgren–Miner rule, the industry standard for measuring the accumulation of material fatigue damage, neglects memory effects and time-ordering dependence, and therefor runs into difficulties dealing with highly intermittent loads with long tailed distributions. In this presentation, we introduce a fast semi-analytical solution for intermittent loads based on the Serebrinsky–Ortiz model of material fatigue, which greatly improves integration speed while still conservatively identifying early failures. Further, we develop a framework for estimating the distribution of failure times for stochastic intermittent loads which reproduces the long left tail.