Rasmus ÿstergaard forside 100%.indd - Solid Mechanics

Interface Fracture Toughness of Sandwich Structures 465
where
and
A2 ¼ 1
þ , I2 ¼ 1
3
where
¼ 1 þ 3
2
A1 ¼ 1 , I1 ¼ 1
12
3 þ
h
1 þ
3 ,
¼ 1 þ 2 þ 2
2 ð1 þ Þ
A3 ¼ 2 þ , I3 ¼ 2 1 1
þ þ
3 3 2 2 þ 12 :
The parameters given in the J-integral solution are
1 1
¼ þ
U A2
1
A1
þ
2
I2
,
1 1
¼ þ
V I2
1
,
I1
REFERENCES
2
1
þ 1
þ 1
" #
,
3
sin
pffiffiffiffiffiffiffi ¼ :
UV I2
1. Zenkert, D. (1991). Strength of Sandwich Beams with Interface Debondings, Composite
Structures, 17: 331–350.
2. Carlsson, L.A. and Prasad, S. (1993). Interfacial Fracture of Sandwich Beams, Engineering
Fracture Mechanics, 44(4): 581–590.
3. Ratcliffe, J. and Cantwell, W.J. (2001). Center Notch Flexure Sandwich Geometry
for Characterizing Skin-core Adhesion in Thin-skinned Sandwich Structures, Journal of
Reinforced Plastics & Composites, 20(11): 945–970.
4. Suo, Z. (1989). Singularities, Interfaces and Cracks in Dissimilar Anisotropic Media,
Proc. R. Soc. Lond. A, 427: 331–358.
5. Liechti, K.M. and Chai, Y.S. (1992). Asymmetric Shielding in Interfacial Fracture under Inplane
Shear, Journal of Applied Mechanics, 59: 295–304.
6. Toftegaard, H. and Goutianos, S. (2006). Composite Skin Elastic Constants from
Monolithic In-plane Specimens and Bonded Out-of-plane Specimens, Journal of Sandwich
Structures and Materials (in press).