PSI - Issue 18

Alexey N. Fedorenko et al. / Procedia Structural Integrity 18 (2019) 432–442 A.N. Fedorenko, B.N. Fedulov, E. V. Lomakin / Structural Integrity Procedia 00 (2019) 000–000

437

6

Fig. 4. Biaxial failure envelope for (0°/ ± 45°/ 90°) AS4/3501–6 epoxy laminate under combined σx and σy stresses

Another verification case for open-hole compression plate is considered by Fedulov et al (2017). A laminated plate is made of T300/976 graphite/epoxy resin with [(±45) 6 ] S lay-up and unidirectional layer properties presented in Table 2. In this problem a nonlinear shear response was considered using relation 1 3 12 12 0 12 12 2 G         with parameter 8 3 2.44 10 MPa      . It allows to achieve both realistic damage distribution in the hole area (Fig. 5) in comparison with one obtained using constant shear modulus, and a nonlinear loading diagram with accurate failure prediction (Fig.6).

Table 2. Material data for open-hole compression problem

E 22 (GPa) 12.96

X t (MPa) 2200

E 11 (GPa) 156.51

G 12 (GPa)

X c (MPa) 2707

Y t (MPa) 102.4

Y c (MPa)

S 12 (MPa) 106.9

Material T300/976

ν 12

6.96

0.23

253

Fig. 5. Left – open-hole compression plate dimensions; right - damage parameter distribution (minimum through the thickness) using linear (top) and nonlinear (bottom) shear response.