复合型裂纹的裂尖三维约束状态分析

3D constraint variations near crack tip of mixed mode

采用修正的边界层理论对Ⅰ /Ⅱ复合型裂尖三维约束状态进行了线弹性的三维有限元分析 .探讨了试样厚度t ,T应力和外载复合度 φ对离面应力参量Tz、离面约束参量 β的重要影响 .

Based on modified boundary layer theory, three dimensional elastic finite element method was applied to investigate the 3D constraint variations near a mixed mode crack tip. The numerical results indicated that the thickness of specimen, T stress and the mixed mode degree all had obvious influences on the following parameters: T z and β (defined to describe the degree of multiaxiality of the stress state). The result is valuable for understanding three dimensional mixed mode crack tip field and the damage mechanism of elastic plates.