COMPUTER TECHNIQUES IN ASSESSING FATIGUE CRACK CLOSURE

摘要

The field of fatigue is 'mature' in the sense that the effects of many influential factors are understood, and life prediction methodologies are well established in many industries. However, a number of major areas remain the subject of controversy, or provide difficulties in terms of reasonably accurate life prediction. Such areas include the behaviour of small fatigue cracks, weldments and fatigue crack closure. Combinations of theoretical and computer-based modelling techniques may offer potential for significant advances in understanding. This paper reports preliminary results from a fundamental study of fatigue crack closure, which seeks to link a theoretical stress solution with automated analysis of photoelastic data, using genetic algorithm optimisation. Results will be compared with those from a finite element (FE) closure model and from experimentally obtained compliance closure data.