Crack Paths 2009

3

C C C D

C C C D-YI

S C B

CCCD-YII

2.0

2

SCB-YI

SCB-YII

1

1.5

*

0

T

-1

1.0

-2

0.5

-3

-4

0.0

0.6

0.8

0.0

0.2

0.4

1.0

0.6

0.0

0.2

0.4

0.8

1.0

Me

Me

Figure 4. Variations of YI ,YII and T* in the tested B Dand S C Bspecimens and for the

full range of modemixities.

Conventional M T S

C C C Dtest data

-9876543210

SCBtestdata

Generalized M T Scurve for C C C Dspecimen

Generalized M T Scurve for S C Bspecimen

0.0

0.2

0.4

0.6

0.8

1.0

M e

Figure 5. Predictions of the generalized M T Scriterion for fracture initiation angle of

C C C Dand S C Bspecimens made of Guiting limestone.

There are several methods for predicting the crack growth path (e.g. [10, 11]). The

incremental crack growth method is a commontechnique and involves a large number

of small crack extensions in appropriate directions. The direction of crack growth for

each increment can be determined by using the generalized M T Scriterion. For each

After

increment the fracture parameters of KI, KII, T are required using Eq. (3).

calculating the direction of maximumtangential stress, the crack is remodeled with a

small extension along the calculated direction and the same procedure is repeated for

the next increment to locate the whole fracture path. This technique was applied using

the A B A Q UfiSnite element code. The simulated incremental crack growth path in one

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