Study on fast crack propagation and arrest behavior of a long crack in steel

钢材长裂纹快速裂纹扩展及止裂行为研究

• 批准号: 03452193
• 负责人: MACHIDA Susumu
• 金额: $ 4.29万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03452193/
• 关键词: Brittle Crack; Arrest Toughness; Cleavage Fracture Stress; Local Fracture Criterion; Energy Release Rate; HRR Stres Field; Long Crack; 長大ぜい性き裂; 伝播停止; 塑性波拡大モデル; エネルギ-論; 応力論; 伝播シミュレ-ション

Crack arrestability of the material has been measured by a crack arrest toughness K_<ca> based on fracture mechanics concept. Recent experimental studies involving dynamic fracture mechanics analysis show that there is a discrepancy between crack arrest property associated with relatively short arrested crack and that with very long crack. This discrepancy may come from the fact that these analyzes are essentially based on Griffith type energy criterion, which is nothing but a necessary condition. Thus, local stress criterion which might be a sufficient condition should be taken into account in order to clarify the crack arrest behavior.In this study, a simple model for brittle crack propagation and arrest in structural steel is proposed. The hall's model is modified to account for plastic work done in the crack tip region, and HRR stress field is assumed to evaluate crack tip local stress. Based on the model proposed, brittle crack propagation and arrest behaviors simulating both conventional and wide plate experiments are analyzed. The results show that local stress criterion rather than energy criterion controls the crack run-arrest process in structual steel.

基于断裂力学概念的裂纹阻止韧性K_ <ca>，已测量了材料的裂纹可阻为。涉及动态断裂力学分析的最新实验研究表明，与相对较短的被捕裂纹相关的裂纹停滞性能与裂纹相对长的裂纹之间存在差异。这种差异可能来自以下事实：这些分析本质上是基于格里菲斯类型的能量标准，这只是必要的条件。因此，应考虑到可能是足够条件的局部应力标准以阐明裂纹停滞行为。在这项研究中，提出了一个简单的脆性裂纹传播模型，并提出了在结构钢中的停滞。修改了大厅的模型以说明在裂纹尖端区域完成的塑料工作，并假定HRR应力场来评估裂纹尖端局部应力。基于提出的模型，分析了模拟常规板和宽板实验的脆性裂纹繁殖和停滞行为。结果表明，局部应力标准而不是能量标准控制结构钢中的裂纹违反过程。

项目成果

町田 進,的場 正明 吉成 仁志,刀根 知佳子: "鋼板の脆性き裂伝播停止挙動に関する一考察" 日本造船学会論文集. 172. (1993)

Susumu Machida、Masaaki Matoba、Hitoshi Yoshinari、Chikako Tone：“钢板脆性裂纹传播停止行为的研究”日本造船学会汇刊 172。（1993 年）。

S.Machida, M.Matoba, H.Yoshinari, K.Tone: "A Modele for Brittle Crack Propagation and Arrest in Atructual Steel" Journal of The Scociety of Naval Architects of Japan. Vol.172. 634-647 (1992)

S.Machida、M.Matoba、H.Yoshinari、K.Tone：“结构钢中脆性裂纹传播和阻止的模型”日本造船学会杂志。