Crack Paths 2009

for the sake of coincision but can be requested from the Authors. An independent

verification of the W Fwas finally obtained by comparing the SIFs calculated with the

W Fwith those of the FE analysis, for the (c) loading condition shown in Fig. 2.

Figure 4. Plot of the coefficients B1Mµ of the W Ffor a/a0 ratio equal to 0.1 and a crack

length a0 of 100 mm.The point data were interpolated with Chebishev polynomial

series. (a) B1I! , (b) B1I! , (c) B1II!, (d) B1II!.

Figure 5. Relative differences between FE and W Fsolutions of KI and KII for the

loading case (c).

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