Issue 44

A. Saoud et alii, Frattura ed Integrità Strutturale, 44 (2018) 25-34; DOI: 10.3221/IGF-ESIS.44.03

Crack length a (mm)

Standard deviation (kN)

Critical load (kN)

Average load (kN)

1 0.81 1.14 0.98 0.80

a=4

0.95

0.13

0.882 1 0.90

0.88

0.07

a=6

0.85 0.801

0.57 0.59 0.60 0.60 0.57 0.54 0.54 0.54 0.55 0.57 0.51 0.40 0.47 0.54 0.61

a=8

0.59

0.01

a=10

0.55

0.01

a=12

0.51

0.07

Table 3: Evolution of the maximum load for each test.

Figure 8: The experimentally defined compliance as a function of the crack length.

To perform the calculations, the following assumptions were assumed:  Wood is a homogeneous material because the dimensions of the specimen are large compared to the difference between the diameters of two consecutive rings.  The elastic behavior is valid.  The orthotropic stiffness matrix is known.  The elastic constants used hereinafter, listed in Tab. 4, were determined using the predictive model developed by

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