Expert system for remnant life prediction of defected components under fatigue and creep-fatigue loadings

Life prediction and management of cracked high temperature structures is a matter of great importance for both economical and safe reasons. To implement such a task, many fields such as material science, structure engineering and mechanics science etc. are involved and expertise is generally required. In terms of the methodology of advanced time-dependent fracture mechanics, this paper developed an expert system to realize an appropriate combination of material database, condition database and knowledge database. Many assessment criteria including the multi-defects interaction and combination, invalidation criterion and creep-fatigue interaction are employed in the inference engine of expert system. The over-conservativeness of life prediction from traditional method is reduced reasonably and therefore the accuracy of predicted life is improved. Consequently, the intelligent and expert life management of cracked high temperature structures is realized which provides a powerful tool in practice. (c) 2006 Elsevier Ltd. All rights reserved.