PE-HD fatigue damage accumulation under variable loading based on various damage models

Despite numerous studies on fatigue of polymer materials under variable loading, there is little work on high-density polyethylene (PE-HD). In this context, an experimental analysis for determining the fatigue strength of PE-100, under constant and variable amplitude loading is presented. Further, the cumulative fatigue damage behavior of PE-100 was experimentally investigated. First, the fatigue curve (S-N: stress vs. number of cycles) was obtained in order to establish the fatigue life of PE-100 subjected to constant stress amplitude. Secondly, Miner's fatigue rule as well as stress-based and energy-based fatigue damage models were used to estimate the cumulative variable amplitude fatigue damage. Comparison between predictions and experimental results showed different trends depending on the choice of prediction model used implying careful fatigue damage consideration when designing under variable amplitude loading.