Abstract

Motivated by the need to quantify uncertainties in the mechanical behaviour of solid materials, we perform simple uniaxial tensile tests on a manufactured rubber-like material that provide critical information regarding the variability in the constitutive responses between different specimens. Based on the experimental data, we construct stochastic homogeneous hyperelastic models where the parameters are described by spatially independent probability density functions at a macroscopic level. As more than one parametrised model is capable of capturing the observed material behaviour, we apply Baye theorem to select the model that is most likely to reproduce the data. Our analysis is fully tractable mathematically and builds directly on knowledge from deterministic finite elasticity. The proposed stochastic calibration and Bayesian model selection are generally applicable to more complex tests and materials.

Highlights

  • The study of material elastic properties has traditionally used deterministic approaches, based on ensemble averages, to quantify constitutive parameters [36]

  • Stochastic models were proposed for nonlinear elastic materials, where the parameters are characterised by probability distributions at a continuum level [37, 65,66,67,68,69]

  • In recognition of the fact that a crucial part in assessing the elasticity of materials is to quantify the uncertainties in their mechanical responses, for rubber and soft tissues under large strain deformations, explicit stochastic hyperelastic models based on datasets consisting of mean values and standard deviations were developed in [37], while statistical models derived from numerically generated data were proposed in [6, 44]

Read more

Summary

Introduction

The study of material elastic properties has traditionally used deterministic approaches, based on ensemble averages, to quantify constitutive parameters [36]. These parameters can meaningfully take on different values corresponding to possible outcomes of the experiments. Stochastic models (described by a strain-energy density) were proposed for nonlinear elastic materials, where the parameters are characterised by probability distributions at a continuum level [37, 65,66,67,68,69].

13 Page 2 of 18
Experimental testing
Specimen manufacture
Experimental set-up
Optical strain measurement
13 Page 6 of 18
13 Page 8 of 18
Stochastic isotropic incompressible hyperelastic models
Hypothesis testing
13 Page 10 of 18
Stochastic calibration
Bayesian model selection
13 Page 12 of 18
Conclusion
A Normal distribution as limiting distribution of the gamma distribution
13 Page 16 of 18
Methods
13 Page 18 of 18

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.