Issue 48

F. V. Antunes et alii, Frattura ed Integrità Strutturale, 48 (2019) 676-692; DOI: 10.3221/IGF-ESIS.48.64

from (a,N) experimental results. Fig. 8 presents experimental crack shapes for different loading directions, which are indicated for each case. The cracks adopted a direction approximately normal to loading direction, i.e., tend to propagate under mode I loading. However, (  ) is not exactly zero and increases with  and with crack length.

R

Test

  º 

 F  N 

0.05 0.05 0.05

1 2 3 4

30 45 60 76

1539 1900 2043 2394

0.05 Table 3 : Experimental parameters used in the tests.

0.02

 =75º

0.016

 =30º

 =60º

75º

 =45º

0.012

y [m]

0.008

 =30º

0.004

0

0.0425 0.0475 0.0525 0.0575 0.0625 0.0675 x [m]

Figure 8 : Experimental crack shapes.

18

present solution; Kv versus x Richard's solution; Kv versus x Richard's solution; Kv versus a

16

-6%

14

12

-31%

10 K v [MPa.m1/2]]

8

6

0.045

0.050

0.055

0.060

x [m]

Figure 9 : Comparison of present solution with Richard’s solution (  =60º).

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