【摘要】 本文首先介绍了用边界元法计算裂纹尖端应力强度因子的基本理论，接着利用边界无法计算厂在均匀内压作用下不同厚壁筒表面椭圆裂纹的应力强度因子，并研究了其大小随椭圆裂纹不同而变化的规律，为厚壁筒结构的设计、制造以及疲劳寿命分析提供了许多有价值的参考资料。更多还原

【Abstract】 In this paper, first, the fundamental theories of calculating stress intensity factor at a crack - tip by BEM are presented. Then, the stress intensity factors are calculated about thick - walled cylinders with various sizes of internal Send - elliptical surface cracks under internal pressure and its change laws are studied. These studies in this paper are very valuable to design, manufacture and fatigue analysis about thick - walled cylinder structures.更多还原