PSI - Issue 18

11

D.A. Bondarchuk, B.N.Fedulov, A.N. Fedorenko / Structural Integrity Procedia 00 (2019) 000 – 000

D.A. Bondarchuk et al. / Procedia Structural Integrity 18 (2019) 353–367

363

T=91C ° T=25C ° (ultimate)

0.00E+00 2.00E+07 4.00E+07 6.00E+07 8.00E+07 1.00E+08 1.20E+08 1.40E+08

T=91C ° T=25C ° (ultimate)

6.81E+07

5.27E+07

4.85E+07

Stress (Pa)

2.54E+07

5.18E+03

2.01E+02

σ 13

σ 22

σ 33

after cut

before cut

after cut

before cut

after cut

before cut

Fig. 7. Comparison stress in composite before, after cut with ultimate stress at T=25 ℃ , T=91 ℃ .

5.2. The study of stress-strain state in specimen during uniaxial tension Fig. 8 shows the results of fracture analysis of the polymerized sample (with the existing residual stresses) under uniaxial tension. The simulation was carried out under conditions of a generalized plane strain state. The developed fracture model, described by Fedulov et al. (2017) and Fedulov et al. (2018), was implemented in ABAQUS. The study of stress-strain state in specimen during uniaxial loading consists from two steps. During the first step of analysis, the residual stresses were read from the technological modeling problem (polymerization of composite sample). During the second step the uniaxial loading was conducted in such way, that the deformations ε 33 increased in the whole section. The Fig. 8 shows the distribution of matrix damage parameters (ψ) obtained with regard to residual stresses. Damage parameter ψ = 1 corresponds to the case when there is n o damage in the matrix, ψ = 0 corresponds to the case when the matrix is destroyed. Fig. 8 also demonstrates the distribution of damage parameters without taking into account technological stresses. The loading was performed from zero values of stress components.

Fig. 8. Damage distribution in the sample with [0°/90°] 12 layup under uniaxial tension (32 elements per 1 layer), on the left - with residual stresses, on the right - without residual stresses.