裂纹间作用机制探讨及微裂纹区对主裂纹的作用效应研究  

Interaction Between Cracks and Effect of Micro-Crack Zone on Main Crack Tip

作　　者：夏晓舟[1,2,3] 章青[1,2] 乔丕忠[1,2,4] 李丽娟[3] 

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,南京210098 [2]河海大学工程力学系,南京210098 [3]广东工业大学建设学院,广州510006 [4]华盛顿州立大学土木与环境工程学院

出　　处：《应用数学和力学》2010年第1期61-70,共10页Applied Mathematics and Mechanics

基　　金：国家自然科学基金资助项目(10972072;50679022;10872052);国家重点基础研究发展计划资助项目(2007CB714104);河海大学水文水资源和水利工程国家重点实验室开放基金资助项目(2009585912)

摘　　要：采用迭加原理和Kachanov提出的简化方法,研究了裂纹间的相互作用机理,分析了不同裂纹布置形式所产生的增强或屏蔽效应,发现当微裂纹沿着或垂直于最大拉应力方向布置时都不产生最大的作用效应,这有别于Ortiz[ASME Journal of Applied Mechanics,1987,54(3):54-58]的结论.还探讨了混凝土类材料的微裂纹的产生机制及微裂纹区对主裂纹尖端产生的作用效应,得出微裂纹区对主裂纹是起增强的作用,增强程度随微裂纹密度和微裂纹长度的增大而增大的结论.The mechanism interaction between cracks with different orientatiows was analyzed based on the principle of superposition and a flattening method. It is found that the maximum interaction effect will not occur when the micro crack is along the direction parallel or perpen- dicular to the principal tensile stress, which is different from the conclusion drawn by Ortiz [ ASME Journal of Applied Mechanics, 1987,54 （ 3 ） ： 54-581. The production mechanism of mi- crocrack and the effect of microcrack zone on main crack tip were also studied. As a result, the microcrack zone has magnifying effect on main crack tip, and such a magnifying effect increases with the increase of micro crack density and length.

关 键 词：迭加原理 应力强度因子 作用效应 微裂纹区 

分 类 号：O346[理学—固体力学]