13th International Conference on Fracture June 16–21, 2013, Beijing, China -6- The extreme value database was constructed by identifying the maximum value of FIP for each statistical volume element (SVE). The number of SVEs was between 25 and 35: they were obtained by the combination of 7 random morphologies (Figure 4-(a)) and 5 isotropic textures (Figure 4-(b)). This sample size is sufficient to determine the extreme values distribution function. Indeed Przybyla showed that from a number of SVEs greater than 20, the difference between the empirical distribution and the experimental sample becomes negligible [3, 4]. The maximum value of FIP has been determined on the one hand from the FIP concerning all the grains of the SVE and on the other hand by separating only the surface grains of the aggregate. (a) grain morphologies MICRO 1 MICRO 2 MICRO 3 MICRO 4 MICRO 5 MICRO 6 MICRO 7 (b) grain orientations Pole figure {100} Pole figure {110} Pole figure {111} ORIEN 1 ORIEN 2 ORIEN 3 ORIEN 4 ORIEN 5 Figure 4. (a) random morphologies and (b) isotropic textures used to create the extreme values database
RkJQdWJsaXNoZXIy MjM0NDE=