TY - JOUR
T1 - Comments on probabilistic fracture mechanics analysis of cracked components
AU - Huh, Nam Su
AU - Shim, Do Jun
AU - Kim, Yun Jae
AU - Lee, Kyu Ho
AU - Kim, Young Jin
PY - 2004
Y1 - 2004
N2 - This paper investigates the effect of elastic-plastic J estimate on calculated failure probabilities for cracked components. To investigate effect of elastic-plastic J estimate on failure probabilities, firstly circumferential through-wall cracked pipes under pure bending is considered, which is important in the leak-before-break analysis. For the analysis, scatters in the applied load, mechanical and fracture properties are considered using normal and log-normal distributions. More importantly, the applied elastic-plastic J-integral is estimated according to four different estimation methods. Resulting failure probabilities are calculated using the efficient first-order reliability method (FORM). The results show that failure probabilities can be significantly different, depending on the elastic-plastic J estimate, suggesting that absolute failure probabilities might have less significance. Based on these investigations, the accuracy of elastic-plastic defect assessment method embedded in API RP579, popularly used in petrochemical industry for integrity assessment of defective structures, is systematically investigated based on the 3-D finite element analyses. The results show that the J estimate in API RP579 can be highly inaccurate for some cases, which in turn would affect failure probabilities.
AB - This paper investigates the effect of elastic-plastic J estimate on calculated failure probabilities for cracked components. To investigate effect of elastic-plastic J estimate on failure probabilities, firstly circumferential through-wall cracked pipes under pure bending is considered, which is important in the leak-before-break analysis. For the analysis, scatters in the applied load, mechanical and fracture properties are considered using normal and log-normal distributions. More importantly, the applied elastic-plastic J-integral is estimated according to four different estimation methods. Resulting failure probabilities are calculated using the efficient first-order reliability method (FORM). The results show that failure probabilities can be significantly different, depending on the elastic-plastic J estimate, suggesting that absolute failure probabilities might have less significance. Based on these investigations, the accuracy of elastic-plastic defect assessment method embedded in API RP579, popularly used in petrochemical industry for integrity assessment of defective structures, is systematically investigated based on the 3-D finite element analyses. The results show that the J estimate in API RP579 can be highly inaccurate for some cases, which in turn would affect failure probabilities.
KW - First Order Reliability Method
KW - Leak-Before-Break
KW - Monte Carlo
KW - Probabilistic Fracture Mechanics
KW - Reference Stress
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M3 - Conference article
AN - SCOPUS:8644230167
VL - 270-273
SP - 1755
EP - 1760
JO - Key Engineering Materials
JF - Key Engineering Materials
SN - 1013-9826
IS - III
T2 - Proceedings of the 11th Asian Pacific Conference on Nondestructive Testing
Y2 - 3 November 2003 through 7 November 2003
ER -