13th International Conference on Fracture June 16–21, 2013, Beijing, China -4- Uniform tensile Unit (mm) Anti-symmetric distributed notches 140.0 Y Z X 24.5 5 8 Fixed end Figure 2. The reference model: epoxy resin thin plate with initial cracks As aforementioned, the mesh configuration determines the candidate crack paths in PDS-FEM, which introduces local heterogeneity into the target model. In order to reduce the effect of this heterogeneity, finer mesh and lower loading speed can be used. The loading rate is the velocity of the top end, which is set to be Vr = 0.252m/s. This velocity is demonstrated to probably generate stable cracks, which means that the crack path solution is not sensitive to the local heterogeneity caused by the mesh setting used in this paper [8]. Also, another mesh with doubled density has been used to make comparison with the current one. The difference is ignorable, which guarantees the availability of current mesh setting for this study. 3.2. Disturbance setting and crack path comparison with reference model In this sub-section, the near field disturbance is modeled by changing the notches’ configuration. The changing is made by adjusting the size, shape and positions of the notches. 3 cases are studied in this part: (1) Size changing: the left notch size elongates from 8mm to 8.5mm along Y axis, while the right notch size shrinks to 7.5mm. (2) Position changing: the distance between the anti-symmetric distributed notches changes from 5mm to 4.5 mm. (3) Out-plane rotation: the notch is designed to rotate along the axis, which is parallel with Y axis, and passes through the centroid of the corresponding notch. Two cases are studied in this paper: (a), left and right notches rotate 5 ; and (b), the left rotates 5 and the right rotates 5 . The minus sign indicates that the direction of the rotation points to the Y axis’ negative direction according to right hand principle. (a). Reference model without disturbance
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