PSI - Issue 42

Jaynandan Kumar et al. / Procedia Structural Integrity 42 (2022) 806–812 Jaynandan Kumar, Anshul Faye / Structural Integrity Procedia 00 (2019) 000–000

811

6

1.0e+00 0.2 0.4 0.6 0.8

0.0e+00 1.0e+00 0.2 0.4 0.6 0.8 1.0e+00 0.2 0.4 0.6 0.8 0.0e+00

1.0e+00 0.2 0.4 0.6 0.8

Phase field (d)

Phase field (d)

0.0e+00

Phase field (d)

Phase fi (d)

0.0e+00

(b)

(a)

Fig. 3. Representation of damage initiating in the RVE, loaded biaxially with stretch ratio 1:1 (a) stretch = 1.15 (b) stretch = 1.16

3. Summary

The objective of the work is to predict the failure envelope of calcified aneurysm under bi-axial loading for di ff erent stretch ratios. Towards that, a unique set of representative elastic and phase-field material parameters are obtained by calibrating the available bi-axial experimental data with the least square minimization principle. Finite element simulation is done for the uncalcified tissue under uni-axial loading with the obtained parameters which describe the deformation and failure of the tissue in the circumferential and longitudinal directions. Simulation is done on the RVE containing 25 percent of calcium particles with 3-dimensional tetrahedral linear elements which is shown above. Further, simulations are being performed on the RVEs for better prediction of failure of the calcified aneurysm.

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