A Fatigue Damage Accumulation Model Considering Load Interaction and Material Parameters Under Variable Load Conditions

This paper proposes a fatigue damage accumulation model that accounts for load interactions and material parameters, addressing the limitations of traditional models under variable loading conditions. The model introduces an exponential function related to cycle life and material elastic modulus, along with a load interaction factor, to derive a formula for residual fatigue damage under multi-level loading. Experiments on ten engineering metallic materials under two-level and multi-level loading validate the model. Predictions for smooth and notched specimens under different loading sequences show strong correlation with experimental data. Compared to traditional Miner theory and Aeran's model, the proposed model offers improved prediction accuracy and robustness, capturing fatigue damage accumulation under complex loading conditions.