LBB裂纹稳定性分析方法研究

破前漏（LBB）分析是一种先进的管道分析评价技术，其关键技术是裂纹的稳定性分析，决定着LBB技术的可用性。本文从核级管道的失效模式出发研究了LBB分析的裂纹稳定性分析问题，并探讨了修正J积分撕裂模量汇交方法(J-T方法)、修正极限载荷分析法以及两倍弹性斜率法的优缺点和适用范围，最后通过工程算例对不同分析方法进行检验，其结论可为我国核电站管道的LBB设计提供参考。

Study on Crack Stability Analysis of LBB Technology

The leak before break (LBB) analysis is an advanced assessment technology for pipes. The key technology of LBB is the crack stability analysis, which decides the usability of the LBB approach. The crack stability analysis problem was studied based on the failure mode of the nuclear grade pipes in this paper. Advantage, disadvantage and application range of the modified J integral tearing modulus intersection method (J-T method), modified limit load method and twice elastic slope method were discussed. Finally, aforementioned methods were applied to an engineering example to verify their validity. Conclusions of this paper can provide some references for the application of the LBB approach to the nuclear power stations of China.