Reliability Analysis of Structures with Multiple Site Fatigue Cracks

多部位疲劳裂纹结构的可靠性分析

• 批准号: 04302034
• 负责人: ITAGAKI Hiroshi
• 金额: $ 7.68万
• 依托单位: YOKOHAMA NATIONAL UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Co-operative Research (A)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04302034/
• 关键词: 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.

1。基于现场疲劳裂纹的无损性分析。不可避免的on Sppection计划的影响与不确定性相关的计划可以分为两个类别。通过侮辱和/或服务经验更新。通过实验方法预测疲劳裂纹的随机模型。该模型是基于疲劳测试的结果，使用相对紧凑的张力应力固定应力压力压力应力应力应力应力应力压力压力压力压力压力压力应力压力应力压力应力应力应力范围，（] sy.upper填充的三角形。主要结果是：1）疲劳裂纹生长的较大范围变化。首次检查时间是通过优化公用事业函数所注意到的整体稳态可靠性NT。

项目成果

板垣浩: "材質の空間的変動の材料試験結果に及ぼす影響について" 日本造船学会論文集. 173. 327-336 (1993)

Hiroshi Itagaki：“论材料特性的空间变化对材料测试结果的影响”日本造船学会汇刊 173. 327-336 (1993)。

Hiroshi Itagaki: ""Estimation of Distribution of Material Properties and its Effect on Fatigue Crack Propagation Life"" Jour.of the Society of Naval Archutects of JAPAN. Vol.175. (1994)

Hiroshi Itagaki：“材料特性分布的估计及其对疲劳裂纹扩展寿命的影响”，日本海军建筑师协会杂志。

Ryuji Miyata: ""Analysis of Embrittlement in Weld Heat-affected Zone due to Formation of Matensitic Islands by Local Criterion Approach"" Jour.of the Iron and Steel Institute of JAPAN. Vol.79. 1183-1189

Ryuji Miyata：“通过局部准则方法分析由于马氏体岛形成而导致的焊接热影响区的脆化”，日本钢铁研究所杂志。

石川浩: "Reliability Assessment of Machines and Structures Based upon Probabilistic Fracture Mechanics." Probabilistic Engineering Mechanics. Vol.8 No.1. 43-56 (1993)

Hiroshi Ishikawa：“基于概率断裂力学的机器和结构的可靠性评估。”概率工程力学第 8 卷第 1 期（1993 年）。

板垣 浩 他: "材質の空間的変動の材料試験結果に及ぼす影響について" 日本造船学会論文集. 173. 327-336 (1993)

Hiroshi Itagaki 等人：“材料特性的空间变化对材料测试结果的影响”日本造船学会汇刊 173. 327-336 (1993)。