Optimum beam design based on fatigue crack propagation

Abstract

This paper deals with an important class of structural problems concerning the fatigue design of elastic beams based on fracture mechanics and probabilistic concepts. The optimization problems taken into account consist in finding the optimal shape of beams in such a way that the volume reaches a minimum, while satisfying prescribed bounds on the stress intensity factor or on the life of the structure. Some of the quantities that describe the model are taken as random while others are deterministic. The analysis has been bounded to the mode I opening of surface crack which is the most important from an engineering point of view.