PSI - Issue 17

B. Boukert et al. / Procedia Structural Integrity 17 (2019) 37–43

42

B.Boukert et al/ Structural Integrity Procedia 00 (2019) 000 – 000

6

ENV1 ENV2 ENV3

ENV1 ENV2 ENV3

SIG YY

0,00

SIG YY

SIG YY

-0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5

Z(mm)

ENV1 ENV2 ENV3

0,00

-2,00

-0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5

-2,00

Z(mm)

-2,00

-4,00

-4,00

-4,00

-0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5

Z(mm)

-6,00

-6,00

-6,00

-8,00

-8,00

-8,00

Fig.4.Transverse stresses SIGyy behavior under MTCF1,2,3 loading.

Fig.6.Transverse stresses SIGyy behavior under MTCF4 loading

Fig.5.Transverse stresses SIGyy behavior under MTCF5 loading

ENV1 ENV2 ENV3

ENV1 ENV2 ENV3

ENV1 ENV2 ENV3

SIG XZ

SIG YZ

SIG YZ

10 11

0 1 2 3 4 5 6 7 8 9 10

0 1 2 3 4 5 6 7 8 9 10

0 1 2 3 4 5 6 7 8 9

Z(mm)

Z(mm)

Z(mm)

-0,6 -0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5 0,6 -1

-0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5 -1

-0,5 -0,4 -0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5 -1

Fig.7. Transverse shear stresses SIG xz MTCF1,2,3,5 loading.

Fig.8. Transverse shear stresses SIG yz MTCF1 loading.

Fig.9. Transverse shear stresses SIG yz MTCF2 loading.

Figures 1 to 9 represent simulations on the behavior of cross ply laminates under different loading types presented in table 2 in 03 different environments in terms of temperature and humidity (Table 3). The purpose of this simulation is to see the influence of the environment (both temperature and humidity) on the behavior of the laminate. For this reason, the simulations are changing from less aggressive environment to more aggressive environments. The first loading -MTCF1- is a hygrothermal loading where the temperature varies linearly; MTCF2 is hygrothermal loading where temperature varies linearly with zero value in the middle of the plate; for MTCF3 loading the boundary condition for temperature are T 0 /2 in the middle, T 0 for z=h/2 , 0 for z=-h/2. MTCF4 is parabolic variation of temperature loading where T=T 0 for z=0 and zero for z=+-h/2; for MTCF5 is parabolic temperature distribution also with T=T 0 for z=0 , T 0 +T 1 +T 2 for z=h/2, T 0 -T 1 +T 2 for z=-h/2 all the previous temperature loading are accompanied with hygroscopic loading given Fick equation. The obtained results by the developed Fortran program was validated using Reddy[3][5][20][21]. The results clearly show the influence of the environment on the constraints. This influence is explained by the hygrothermal deformation growth while increasing the environmental values. We notice that longitudinal stress sigxx in loadings MTCF1,2,3 behaves in a symmetrical way despite the non-symmetric temperature loading. In this case the behavior is dominated by the hygroscopic stress which are in their turn symmetrical. For MTCF4 loading, where a parabolic loading of temperature is imposed, the stress is symmetrical. In MTCF5 loading a stagnation of the stress in the internal layers is found because of saturation in terms of hygroscopy accelerated by the high temperature produced by the temperature gradient. The same comments are applicable to the transverse stress, transverse shear stress are also influenced by the hygrothermal environment.