厚壁圆筒内壁半椭圆形多裂缝应力强度因子的研究  

A Study of the Stress Intensity Factors of Multiple Semi Elliptical Cracks

作　　者：张永弘[1] 崔旭明[1] 何富军 刘恩[1] 

机构地区：[1]大庆石油学院

出　　处：《应用力学学报》2000年第1期150-156,共7页Chinese Journal of Applied Mechanics

摘　　要：通过受内压厚壁圆筒内表面环向均布与非均布多个纵向半椭圆形裂缝大量的三维光弹性实验 ,测量了其应力场和“应力强度因子”( SIF) ,得到了它们的变化规律 ,研究了使 SIF变化的“载荷松弛”现象的机理 ,发现了在有裂缝的应力场中“附加弯矩”的出现是“载荷松弛”现象的本质 ,建立了无因次“附加弯矩”和“载荷松弛因子”( LRF)的表达式 ,利用 LRF概念和实验结果以及有关学者的结果建立了相对分布两个不同裂缝以及环向均布和非均布半椭圆形多裂缝 SIF的近似计算式 ,用三维趋势面描绘了它们的变化规律 ,给出了工程上的应用方法和实例。In this paper, much 3 D photo elastic experiment was applied on an internal pressurized thick walled cylinder with multiple longitudinal semi elliptical internal surface cracks distributed uniformly and non uniformly along the circle. The stress field and the stress intensity factor (SIF) were measured. Their changing regularity was derived. The Load Relief mechanism changing the SIF was studied. The nature of ‘Load Relief’ is the appearance of ‘Additional Bending Moment’ (ABM) in the stress field with cracks. The approximate expressions for nondimensional ABM and Load Relief factor (LRF) were derived. By mean of the idea of LRF results of the experiment, and the work of some relating scholars, the approximate calculating expressions were presented in opposition to double different cracks and multiple longitudinal semi elliptical internal surface cracks distributed uniformly and non uniformly along the circle. An example in engineering was given.

关 键 词：厚壁圆筒 裂缝 载荷松弛 应力强度因子 压力容器 

分 类 号：O346.1[理学—固体力学] TH49[理学—力学]