PSI - Issue 52

Angela Russo et al. / Procedia Structural Integrity 52 (2024) 535–542 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

538

4

E 11 [MPa]

E 22 = E 33 [MPa]

G 12 = G 13 [MPa]

G 23 [MPa]

ν 12 = ν 13 [-]

ν 23 [-]

G Ic [kJ m

-2 ]

IIc [kJ m

-2 ]

G

122 000

6265

4649

4649

0.3008

0.02

0.258

1.9

Table 2. Stacking sequences.

Number of plies Lay-up

Skin

16

[45/0/90/-45]2s [45/0/90/-45]2s

Stringer foot 16 Stringer web 32

{[45/0/90/-45]2s}s

Contact elements have been used to join the skin shell part to the skin solid part, as shown in Figure 3, along with the contacts used to attach the stringer to the skin. In particular, these latter elements are “bonded” and, when and where the delamination growth criterion is satisfied, they are released. This capability is known as “birth and death” and can be enabled through the use of a specific key-option of the element type. To prevent penetration, general surface contact elements have been placed between the skin and the stringer foot in the debonding region.

Tie contact to bond the skin shell and skin solid part

Contact with “birth and death” capability

Figure 3. Contact elements.

Finally, the boundary conditions, shown in Figure 4, have been imposed on the nodes of both the panel edges. One side have been constrained, hence setting to zero both displacements and rotations degree of freedoms, and compressive displacements have been applied on one edge of the panel, as shown in Figure 3.

Figure 4. Boundary conditions