Issue 58
K. Benyahi et alii, Frattura ed Integrità Strutturale, 58 (2021) 319-343; DOI: 10.3221/IGF-ESIS.58.24
This strain is a consequence of opening the cracks too large. This fracture strain of the inclusions is limited as follows:
= rt ft
(50)
The damage is progressive in the field of strains. For a uni-axial state of tension, the equivalent strain ( ) ( ) 1 2 , t t D D , in the nonlinear field is such that:
( ) → = = → = = ft u 1 u r 2 t t D D ( )
=
( ) ( E E D D 1- 1-
)
ct
t
1
t
1
(51)
=
(
) (
)
1- E E D D 1
ct
t
2
t
2
and
( f ,
) ( ) =
D D
-
0
t
1
t
1 ft
( ) 1 t D
→ r
(52)
ft
( f ,
) ( ) =
D D
-
0
t
2
t
2 r
Figure 6: Damage model algorithm implementation diagram.
The threshold function defines two limit states: - An elastic state ( ) ft . - A breaking limit given by the value ( ) r . Such as:
→
D
=0
=
ft
t
1
( f ,
)
= → 0
D
(53)
t
1
=
→
D
=0
r
t
2
330
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