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H. Askes et alii, Frattura ed Integrità Strutturale, 25 (2013) 87-93 ; DOI: 10.3221/IGF-ESIS.25.13 89 eff y L 0, r 2             Point Method (PM) (6)   2L eff y 0 1 0, r dr 2L       Line Method (LM) (7)   L2 eff y 2 0 0 4 , r drd L          Area Method (AM) (8) The adopted symbols as well as the meaning of the effective stress determined according to definitions (6), (7), and (8) are explained in Fig. 1. (a) (b) (c) (d) Figure 1 : Definition of the local systems of coordinates (a) and effective stress,  eff , calculated according to the Point Method (b) , Line Method (c) , and Area Method (d) . Eq. (4) to (8) clearly show that inherent material strength  0 plays a role of primary importance when the TCD is used to design cracked components against static loading. Brittle materials are experimentally seen to have an inherent material strength which is always very close to the material ultimate tensile strength,  UTS [14-16]. On the contrary, when the fast fracture process zone is characterised by large scale plastic deformations, in general,  0 reaches a value which is somewhat larger than the plain material UTS [10, 11, 13]. Another important aspect which is worth highlighting here is that  0 adopts a value higher than  UTS also in those situations in which the breakage of the plain parent material occurs by different mechanisms (such as, for instance, by the propagation of pre-existing microstructural defects) [10]. The considerations reported above clearly suggest that the only way to accurately determine  0 is by testing notched specimens containing stress risers whose presence results in different stress distributions in the vicinity of the tested geometrical features [10-13]. To conclude, when the TCD is used to specifically design cracked engineering ceramics against static loading, the inherent material strength is seen to be equal to the material ultimate tensile strength [15]. This greatly simplifies the problem. According to this remark, in what fallows GM will be used to model the sensitivity of engineering ceramics loaded in Mode I to both short- and long-cracks by taking  0 invariably equal to  UTS . L INKING THE LENGTH SCALES OF GM AND THE TCD y using the Area Method argument re-interpreted according to non-local mechanics, in two recent investigations [17, 18] we have proven that the length scale parameter, l , employed by GM to perform the stress analysis, Eq. (1), can directly be related to critical distance L, Eq. (5). Since the reasoning resulting in the l vs. L relationship has B