선체 용접부의 균열진전 및 피로수명예측에 관한 연구(Ⅱ)

• Published in: 大韓造船學會 論文集 Vol. 45; no. 6; pp. 679 - 687
• Main Authors: 김경수(Kyung-su Kim), 심천식(Chun-sik Shim), 권영빈(Young-bin Kwon), 고희승(Hee-seung Ko), 기혁근(Hyeok-geun Ki), K.K. Viswanathan
• Format: Journal Article
• Language: Korean
• Published: 대한조선학회 2008
• Subjects: AFGROW(Air Force Growth); Residual stress(잔류응력); Thermal elastic-plastic analysis(열탄소성해석); Inner bottom longitudinal connection(선저종이음부); Crack initiation life(균열개시수명); Crack propagation life(균열진전수명); Fatigue life prediction(피로수명예측); Welded joint(용접 이음부)
• ISSN: 1225-1143; 2287-7355

The fatigue life of ship structure under cyclic loading condition is made up of crack initiation and propagation stages. For a welding member in ship structure, the fatigue crack propagation life is more important than the fatigue crack initiation life. To calculate precisely the fatigue crack propagation life at the critical welding location, the knowledge of the residual stress sensitivity on the fatigue strength is necessary. In this study, thermo elastic-plastic analysis was conducted in order to examine the effect of residual stress on the fatigue crack propagation life. Also the fatigue crack propagation lives considering residual stress were calculated using fatigue crack growth code, AFGROW, on the basis of fracture mechanics. AFGROW is widely used for fatigue crack growth predictions under constant and variable amplitude loading. The reliability of AFGROW on the fatigue of ship structure was confirmed by the comparison of the estimated results with the fatigue propagation test results.