摘要
应力强度因子K的计算是裂纹扩展分析的重要内容,它从能量释放的角度来分析和预测裂纹的成长趋势。现有的有限元分析程序基于材料断裂特性的理论,只能独自完成二维裂纹扩展计算。并不适合应用到管道裂纹.特别是表面裂纹的穿透和扩展分析模拟上。本文应用ABAQUS程序为断裂性能的计算工具,开发专用的功能,引入Paris—law中da/dN与△K的关系,采取基于AK的实时裂纹扩展后有限元重构迭代方法,实现管道三维裂纹两向疲劳扩展的分析模拟,克服了现有程序的局限。在此基础上,分析研究了不同裂纹形式、不同载荷情况的裂纹扩展规律.为在役管道安全运行寿命评估及LBB技术的进一步运用打下了基础.
The calculation of stress intensity factor K is a key part of crack growth analysis. The crack growth trend can be analyzed and predicted by K in the perspective of energy releasing. Current fi- nite element software can only solve two-dimensional crack growth problems based on the material frac- ture property, and it is not applicable to analyze pipe crack growth, especially to the penetration and propagation of pipe surface crack. This paper takes ABAQUS as the fracture property computational tool, and develops special functions to overcome the limitation of FE software above-mentioned. Pipe crack growth in two directions of 3D case can be obtained using a reconstruction iterative approach based on the relationship between da/dN and AK in Paris-law. And then the crack growth of different loads and forms is analyzed and the corresponding laws are obtained, which are bases for further application of LBB tech- nology and estimation of operation safety of the pipeline in services.
出处
《核电工程与技术》
2013年第1期34-40,共7页
Nuclear Power Engineering and Technology
关键词
环向裂纹
应力强度因子
裂纹扩展
重构迭代
circumferential cracks, stress intensity factor, crack growth, reconstruction iterative approach