Issue 43

L.C.H. Ricardo, Frattura ed Integrità Strutturale, 43 (2018) 57-78; DOI: 10.3221/IGF-ESIS.43.04 63 Figure 3 : Dugdale Plastic Zone Strip Model [17]          2 cos ys I x K a r ar a r (2.23)        K a r (2.24) But, K σ = K I and the simplified equation takes the form     cos 2 ys x ar a r (2.25) Let    2 ys y so that   cos x y a r (2.26)   (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