NEW DESCRIPTION OF MICROCRACK DAMAGE BASED ON CONSERVATION LAWS

• 来源期刊: 力学学报（英文版）
• 学科: 物理学
• 年，卷（期）: 2002,（5）
• 页码范围: 429-440
• 页数: 12页
• 分类号: O3
• 语种: 英文

摘要

This paper presents a new description for brittle solids with micro-cracks under plane strain assumption. The basic idea is to extend the conservationlaws such as the Jj-vector and M-integral analysis used in single crack problems tostrongly interacting crack problems. The M-integral contains two distinct parts. Oneof them is a summation from the well-known relation between the M-integral and thestress intensity factors (SIF) at both tips of each crack. The other, called as theadditional contribution, is obtained from the two components of the Jj-vector andthe coordinates of each microcrack center in a global system. Of great significanceis the clarification of the confusion about the dependence of the M-integral on theorigin selection of global coordinates, provided that the vector vanishes at infinityand that the closed contour chosen to calculate the integral and the vector enclosesall the microcracks completely. The M-integral is equivalent to the decrease of thetotal potential energy of the microcracking solids with the strong interaction beingtaken into account. The M-integral analysis, from a physical point of view, doesplay an important role in evaluating the damage level of brittle solids with stronglyinteracting microcracks.