Structural durability design optimisation and its reliability assessment

Mechanical fatigue subject to external and inertia transient loads in the service life of mechanical systems often leads to structural failure due to accumulated damage. A structural durability analysis that predicts the fatigue life of mechanical components subject to dynamic stresses and strains is a computer-intensive, multidisciplinary simulation process, since it requires the integration of several computer-aided engineering tools and large amounts of data communication and computation. Uncertainties in geometric dimensions result in the indeterministic fatigue life of a mechanical component. Uncertainty propagation to structural fatigue under transient dynamic loading is not only numerically complicated but also extremely expensive. It is, therefore, a challenge to develop a durability-based design-optimisation process and reliability analysis to ascertain whether the optimal design is reliable. The objective of this paper is to develop an integrated CAD-based computer-aided engineering process to effectively carry out design optimisation for structural durability, yielding a manufacturable, durable, and cost-effective product. In addition, a reliability analysis is executed to assess the reliability of the deterministic optimal design.