Reliability Analysis of Structures with Multiple Site Fatigue Cracks
Grant-in-Aid for Co-operative Research (A)
|Allocation Type||Single-year Grants|
|Research Institution||YOKOHAMA NATIONAL UNIVERSITY|
ITAGAKI Hiroshi YOKOHAMA NATI.UNIV.PROFESSOR, 工学部, 教授 (10017882)
ISHIZUKA Tetsuo YOKOHAMA NATI.UNIV.LECTURER, 工学部, 講師 (50017927)
FUJIMOTO Yukio UNIVERSITY OF HIROSHIMA PROFESSOR, 工学部, 教授 (60136140)
ISHIKAWA Hiroshi UNIVERSITY OF KAGAWA PROFESSOR, 経済学部, 教授 (60026200)
MIYATA Ryuji UNIVERSITY OF NAGOYA PROFESSOR, 工学部, 教授 (20023228)
SHIMIZU Akinobu YOKOHAMA NATI.UNIV.PROFESSOR, 工学部, 教授 (10015547)
森下 信 横浜国立大学, 工学部, 助教授 (80166404)
飯田 國広 芝浦工業大学, 工学部, 教授 (10010737)
|Project Period (FY)
1992 – 1993
Completed(Fiscal Year 1993)
|Budget Amount *help
¥12,000,000 (Direct Cost : ¥12,000,000)
Fiscal Year 1993 : ¥3,800,000 (Direct Cost : ¥3,800,000)
Fiscal Year 1992 : ¥8,200,000 (Direct Cost : ¥8,200,000)
|Keywords||RELIABILITY / FATIGUE CRACK / MULTIPLE SITE CRACKS / 疲労亀裂 / 構造信頼性 / 破壊特性 / 検査計画 / 確率モデル / ベイジアン|
1. Reliability Analysis based on Non-Destructive Inspection of Structures with Multiple Site Fatigue cracks.
The influence of inevitable uncertain parameters on inspection planning was discussed. The uncertainties related to inspection planning can be classified into two categories : engineering uncertainty and economical/social uncertainty. Initial uncertainty can be gradually reduced by being updated through inspection results and/or service experience. The Baysian analysis is applied in conjunction with the sequential cost minimization method for a member set which has an uncertainty in the fatigue property of members.
2. Estimation of Distribution of Material Properties and its Effect on Fatigue Propagation Life.
A stochastic model for predicting fatigue crack growth was discussed by experimental approach. The model is based on the results of fatigue test using relatively large compact-tension-specimen under constant stress intensity factor range, (〕SY.upper filled triangle.〔) K, condition. The main results are : 1) There are large scale variation and small scale variation of material properties of fatigue crack growth. 2) It is very important to model the statistical correlation of material properties along crack path, particularly when the correlation length is large.
3. Selection of the First Inspection Time based Maximization of Amount of Information.
The first inspection time heavily infuences the overall structural reliability, and therfore several cost components as was noticed from pervious works. By optimizing an utility function, here simply regarded as mean Shannon information, a suitable criteria for selecting the first inspection time was discussed.
Research Products (18results)