Structural optimization with fatigue life constraints

This paper presents a method for considering fatigue life requirements in the optimal design of structures. The basic concept is to use the load history data combined with the finite element stresses of the structure and the material fatigue properties to calculate the fatigue life during the optimization process. The life requirement is considered as side constraints and the structure weight as the objective function. To demonstrate the concept, the optimization task with fatigue life constraints and the fatigue life calculation, based on the contemporary approach, are discussed. Some optimum design test cases, using the SAE keyhole specimen experimental fatigue data, are presented.