Issue 43

L.C.H. Ricardo, Frattura ed Integrità Strutturale, 43 (2018) 57-78; DOI: 10.3221/IGF-ESIS.43.04

Figure 3 : Dugdale Plastic Zone Strip Model [17]



2

x

ys



  a r ar

 



K

cos

(2.23)

I



 a r







 

 a r

K

(2.24)



But, K σ

= K I

and the simplified equation takes the form

  2 ys   2 ys

x



ar

(2.25)

cos

 a r



y

so that

Let

x



y

(2.26)

cos

 a r

  (sec 1) r a y

(2.27)

Expanding the trigonometric function eq. (2.27) yields and neglecting the high order terms from (2.27) becomes:

2

  2 2 2 2 ys ay a   

   

  

r

(2.28)

Substituting eq. (2.28) into (2.14) gives the corrected stress intensity factor due plasticity at the crack tip and crack geometry

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