Reliability‐Based Design Optimization Considering Probabilistic Degradation Behavior

This article proposes a reliability‐based design optimization methodology by incorporating probabilistic degradation in the fatigue resistance of material. The probabilistic damage accumulation is treated as a measure of degradation in the fatigue resistance of material and modeled as nonstationary probabilistic process to capture the time‐dependent distribution parameters of damage accumulation. The proposed probabilistic damage accumulation model is then incorporated into reliability‐based design optimization model by building a dynamic reliability model inferred from the stress–strength interference model. The proposed approach facilitates to capture the dynamic degradation behavior while optimizing design variables at an early design stage to improve the overall reliability of product. The applicability of the proposed approach is demonstrated using suitable examples. Copyright © 2012 John Wiley & Sons, Ltd.