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At a certain crack size
(
a=const
), one can write
I
a
K F
|
α
= ⋅
(11)
Thus at every point α can be calculated from the following equation which combines
the R-Curve and the load curve as looking for the critical loading:
I
J E
K J E F f ( a ) F
f ( a )
⋅
= ⋅ = ⋅
⇒ =
(12)
where
f (a)
is calculated from the geometrical configuration
I
j
K ( a )
f ( a )
F
=
taking into
account that
F
j
= const along a load curve j. In fact, this is the curve that touches the R-
Curve. Now calculating
d( F )
d( a )
Δ
from the obtained points, one obtains the critical crack
Δa
0
and critical load
F
j
=
F
critical
at that point.
2.4.4. Strength mismatch: Deformation pattern
This option is available only if Strength mismatch was chosen. Here, the deformation
pattern is to be selected from the dialog shown in Fig. 17.
Figure 17: Deformation patterns for strength mismatch