Shape Optimization for Prolonging Fatigue Life

Abstract

Shape optimization for two types of specimens in opening mode and a cantilevered beam in mixed mode was accomplished by the linear elastic fracture mechanics and the growth-strain method. Linear elastic fracture mechanics was used to evaluate the stress intensity factors and fatigue lives. And the growth-strain method was used to optimize a shape. From the results, it was found that the optimized shapes of two types of specimens and a cantilevered beam greatly prolong their fatigue lives, and the growth-strain method is an appropriate technique for shape optimization of a structure having a crack.