Fatigue Crack Paths 2003

Someresults are plotted in Figs. 5-8 where FE data and predicted values are compared

for different models and load conditions.

By using an error index defined as

σ − σ

F E M y % σ

predictedy

= δ

100

(23)

max

Tables 3 and 4 make it possible a comparison at different distances from the notch

tip. The agreement between numeric and analytical predictions is seen to be very good

also at great distances from the notch tip.

Table 2. Geometry of FE models. (a) plates with double edge notch (PDEN); (b-c)

plates with an edge notch (PEN) subjected to tensile load and three point bending,

respectively; (d) bars with a circumferential notch (BCN).

Notch Notch Ligament Ligament Diameter

(b) Kt

net (c) Kt

MoNod.el Tnyoptechof d[empatmh] r[admρimus] [mwimdh]th(a) [mwmi]dht(bh-c)

[mmd] (d) Kt(nae)t Kt net

net

(d)

1 Semi-circ 2.5

2.5

10

5

10 1.62 3.65 2.91 1.50

40

20

40 2.35 2.97 4.23 2.25

2 Semi-circ 2.5

2.5

160

80

160 2.83 3.00 5.55 2.79

3 Semi-circ 2.5

2.5

4

U 10 0.5

40

20

40 5.56 11.85 9.31 5.07

40

20

40 5.15 7.88 8.95 4.81

5

U 5 0.5

0.5

40

20

40 4.51 5.64 8.13 4.31

6

U 2.5

7

U 10 2.5

40

20

40 2.69 5.84 4.53 2.46

8

U 5 2.5

40

20

40 2.57 4.44 4.46 2.40

40

20

40 5.55 11.834 9.30 5.06

9 V(45°) 10 0.5

10 V (45°)

5 0.5

40

20

40 5.15 7.87 8.93 4.80

11 V (45°) 2.5

0.5

40

20

40 4.51 5.63 8.12 4.31

40

20

40 2.89 5.84 4.53 2.47

12 V (45°) 10 2.5

13 V (45°)

40

20

40 2.57 3.99 4.46 2.40

5 2.5

14 V (90°) 10 0.5

40

20

40 5.30 11.40 8.90 4.85

15 V (90°)

5 0.5

40

20

40 5.00 7.67 8.67 4.66

40

20

40 4.44 5.55 7.99 4.24

0.5

16 V (90°) 2.5

17 V (90°) 10 2.5

40

20

40 2.66 5.81 4.50 2.45

18 V (90°)

5 2.5

40

20

40 2.56 3.98 4.44 2.39

19 V (135°) 10 0.5

40

20

40 3.95 8.82 6.82 3.67

20 V (135°) 5 0.5

40

20

40 3.90 6.13 6.81 3.66

40

20

40 3.70 4.68 6.65 3.53

0.5

21 V (135°) 2.5

22 V (135°) 10 2.5

40

20

40 2.37 5.32 4.11 2.21

23 V(135°) 5 2.5

40

20

40 2.34 3.71 4.11 2.20