Characterization of interaction between elliptical subsurface flaws

内部欠陥間応力拡大係数の相互作用評価について

東 喜三郎*; Li, Y. ; 長谷川 邦夫

Azuma, Kisaburo*; Li, Y.; Hasegawa, Kunio

Multiple flaws are often observed in engineering structures and components. Since interaction between multiple flaws may lead to increase of the stress intensity factors, fitness-for-service codes provide combination rules to consider the effect. However, the criteria for flaw combination are not unified among the codes. In order to establish a reasonable combination rule, it is necessary to clarify what parameter is dominant to interaction. The interactions of stress intensity factors for two coplanar subsurface flaws in a plate were investigated. The plate was subjected to a remote tension acting normal to the flaw surface. The stress intensity factor solutions for the elliptical subsurface flaws with various shapes and distances were obtained from finite element analyses. It was concluded that distance and flaw area are important parameter to characterize interaction factor between two subsurface flaws.