A PROBABILISTIC FATIGUE LIFE ESTIMATION APPROACH FOR COMPLEX STRUCTURE AND COMPONENT

Abstract

Fatigue life corresponding to specific failure probability is much more significant than mean life, since fatigue fracture is a highly uncertain phenomenon. For a complex structural component with several damage sites, the contributions of the every damage site are stochastic in nature. Moreover, the damages or fatigue lives of the individual vulnerable sites are neither completely correlated nor perfectly independent of each other. The present paper develops a probabilistic fatigue life evaluation approach to predict the probabilistic fatigue life of complex mechanical or structural components containing multiple damage sites. By correctly dealing with the failure dependence of the every damage sites and characterizing the fatigue life random variable of a multi-site-damage (MSD) structure or component using the extreme statistic of the fatigue lives of the individual damage sites, probabilistic fatigue life of MSD structural component is reasonably predicted.