Fatigue Crack Paths 2003

r-rOIh/2. A s a result w e can assumeK = h/2 , while the index m needs to be calculated

involving the equilibrium condition:

r0+h/2

H 2

] 6 (r—r0)dr—6

(9)

to

y

_ n omgross

In order to derive an explicit relation useful to evaluate m, Eq. 8 is introduced into Eq. 9

so that

7.1-1

rout/2

Gmax

{1_r—r0] 4 (q_1) 1+ atan[(r—r0)m] +

To

4 (q—1)+qw1

h/2

Tom

t11—l

2

r

h

H

‘1' (1 (D1

‘1' 1.0 _ 1.] d f: (snomgross

Eq. 10 can be solved by a numeric routine. A first trial value for m can be derived by

noticing that in infinite width components (when r tends to infinite), the following

relation is valid:

(11)

Consequently

It mtrial : 5

1

(12)

w h e r eo is the m a x i m nuominalstress referredto the net section. I] o mn e t

Plate with edge notch subjected to tensile loading (PEN)

Another classical problem regards plates with a single notch, subjected to a remotely

applied tensile load. Dueto the lack of symmetry, the net section is subjected to tensile

and bending stresses. As a result, both parameters m and K need to be determined by

means of two equilibrium conditions. Equilibrium conditions on force and moment

result in:

r0 +h

6 dy r = 6 n o m g r o s s H