PSI - Issue 7

M. Cova et al. / Procedia Structural Integrity 7 (2017) 446–452

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M. Cova et Al./ Structural Integrity Procedia 00 (2017) 000–000

Fig. 5. Region where the presence of the second ellipse gives an increasing of σ θ / σ max,w greater than 10%.

σ ϑ / σ max,w or K I /K 0

points B, C ellipse (b/a=0.1)

2b

B

2b

D

A

C

points A, D ellipse (b/a=0.1) points B, C crack (cf. Rooke, Cartwrigth )

r

2a

2a

B

D

A

C

r

2a

2a

r/a

Fig. 6. Magnification factor for collinear ellipses or cracks in a sheet subjected to a uniform uniaxial tensile stress