Mixed-mode (I/II) rupture assessment of rubber-like materials weakened by cracks using the averaged strain energy density criterion

In the present study, the application of the averaged strain energy density (ASED) criterion is extended from pure mode-I to mixed-mode (I/II) loading for hyperelastic materials. Indeed, the use of a recently proposed method by the present authors for determination of the critical values of strain energy density and radius of control volume in mode-I loading has been generalized to the mixed-mode loading conditions. The key point in the generalization is the almost uniaxial state of stress fields near the crack tip in rubber-like materials. To validate the accuracy of the criterion in mixed-mode (I/II) loading, a new set of experiments on rubbers weakened by cracks has been carried out. The experimental results confirm the accuracy of the ASED criterion in the case of cracked rubbers under mixed-mode (I/II) loading.submittedVersionThis is a submitted manuscript of an article published by Elsevier Ltd in Theoretical and applied fracture mechanics, 25 May 2017

Rupture analysis of rubber in the presence of a sharp V-shape notch under pure mode-I loading

The rupture behavior of styrene-butadiene rubbers (SBR) in the presence of a V-shape notch is investigated for the first time both experimentally and theoretically. In the experiments, V-notched samples of SBR are tested under tensile loading and their rupture displacements are determined. Afterwards and in the analytical field, the rupture loads of tested rubbers are predicted using the averaged strain energy density (ASED) criterion. The key idea of this criterion (i.e. the almost uniaxial state of stress field near the notch tip) is verified through non-linear finite element modeling. It is shown that good agreement exists between the predictions of the ASED criterion and the experimental results obtained for SBR. Moreover, the microscopic study of the ruptured surfaces of the notched SBR demonstrates its high roughness which can be attributed to the resistance of the rubber chains against the crack growth

Mixed-mode (I/II) rupture assessment of rubber-like materials weakened by cracks using the averaged strain energy density criterion

In the present study, the application of the averaged strain energy density (ASED) criterion is extended from pure mode-I to mixed-mode (I/II) loading for hyperelastic materials. Indeed, the use of a recently proposed method by the present authors for determination of the critical values of strain energy density and radius of control volume in mode-I loading has been generalized to the mixed-mode loading conditions. The key point in the generalization is the almost uniaxial state of stress fields near the crack tip in rubber-like materials. To validate the accuracy of the criterion in mixed-mode (I/II) loading, a new set of experiments on rubbers weakened by cracks has been carried out. The experimental results confirm the accuracy of the ASED criterion in the case of cracked rubbers under mixed-mode (I/II) loading

Rupture analysis of rubber in the presence of a sharp V-shape notch under pure mode-I loading

The rupture behavior of styrene-butadiene rubbers (SBR) in the presence of a V-shape notch is investigated for the first time both experimentally and theoretically. In the experiments, V-notched samples of SBR are tested under tensile loading and their rupture displacements are determined. Afterwards and in the analytical field, the rupture loads of tested rubbers are predicted using the averaged strain energy density (ASED) criterion. The key idea of this criterion (i.e. the almost uniaxial state of stress field near the notch tip) is verified through non-linear finite element modeling. It is shown that good agreement exists between the predictions of the ASED criterion and the experimental results obtained for SBR. Moreover, the microscopic study of the ruptured surfaces of the notched SBR demonstrates its high roughness which can be attributed to the resistance of the rubber chains against the crack growth.submittedVersionThis is a submitted manuscript of an article published by Elsevier Ltd in International Journal of Mechanical Sciences, 13 August 2018

Averaged strain energy density criterion for rupture assessment of cracked rubbers: A novel method for determination of critical SED

In the present study, the application of averaged strain energy density (ASED) criterion has been extended to hyperelastic materials. Because of the material and geometry nonlinearities, commonly known for rubber-like materials, the use of conventional relations for determining the criterion parameters is no longer allowable. Therefore, by taking the advantage of a simple uniaxial state of stress field ahead of the crack tip in hyperelastic materials, a novel method has been proposed for determining the critical value of strain energy density. The sound agreement between the theoretical estimates based on the employed ASED criterion and the experimental data, taken from the literature, confirms the suitability of the proposed method

A New Criterion for Rupture Assessment of Rubber-Like Materials under Mode-I Crack Loading: The Effective Stretch Criterion

A new criterion is presented for fracture assessment of rubber-like materials weakened by a mode I crack. The criterion is based on two main assumptions: the existence of a damage zone around the crack tip and the dominant uniaxial nature of the stress field near the crack in rubber-like materials. Considering these key features and employing the concepts of well-known eight-chain model, first, a failure criterion called the "Effective Stretch Criterion" has been proposed. Then, a procedure has been elaborated to calibrate the material parameters in the criterion. The criterion, finally, has been validated by using two sets of experimental data available in the literature

Fracture analysis of V‐notched rubbers: An experimental and theoretical study

In this study, the rupture load in rubbers weakened by sharp V‐notch is investigated under mode I loading. To this end, first, mode I fracture tests are performed on V‐notched samples made of styrene‐butadiene rubbers and the corresponding rupture loads are obtained. Then, the effective stretch (ES) criterion, which was recently developed by the present authors for rupture assessment of cracked rubber parts, is extended and used for the V‐notched rubbers. It is shown that similar to cracked rubbers, the state of stress near the notch tip is also nearly uniaxial. By employing the ES criterion, the critical displacements corresponding to the rupture in the tested samples are calculated. Finally, the predictions of the criterion are compared with the corresponding experimental values, and good consistency is shown to exist.submittedVersionThis is the pre-peer reviewed version of an article, which has been published in final form at [https://doi.org/10.1111/ffe.12947]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving