PSI - Issue 28

746 4

D.A. Bondarchuk et al. / Procedia Structural Integrity 28 (2020) 743–751 Author name / Structural Integrity Procedia 00 (2019) 000–000

Fig. 2. FEM of the specimen with [0 0 /90 0 ]

12 layup, mesh density on the region of free edge 8 elements per layer and crack 6 mm long

4. Methodology description The distribution of the local strain energy release rate along the delamination front is obtained via using seam crack technique applied to 2D finite element models of straight delamination area embedded in multilayered composite. The use of commonly used virtual closure crack technique (VCCT) and extended finite element method (XFEM), described in Abaqus 6.14 Documentation (2020), were not applied in mind the limited use of method during coupled temperature displacement analysis. The crack 0.5, 1, 2 and 6 mm long was placed between 0° and 90° layer. For each length of crack were calculated fracture criteria f I and f II according to the formulae (1) and (2), provided by Mabson G. (2003), during cure of sample and after cutout.

R

   



1 2

1

G

y

f

I   



(1)

     

I

G

a b G

IC

IC

1 2

1

u R

G

  



f

II   



x

(2)

     

II

G

a b G

IIC

IIC

The calculation scheme of G I and G II is shown in Fig.3.

Fig. 3. Calculation of G I и G II (MCCI process) for 4-nodal rectangular elements.