ABSTRACT: Tire failures, such as tread separation and sidewall zipper fracture, occur when
internal flaws (cracks) nucleate and grow to a critical size as result of fatigue or cyclic loading.
Sudden and catastrophic rupture takes place at this critical crack size because the strain energy
release rate exceeds the tear energy of the rubber in the tire. The above-mentioned tire failures
can lead to loss of vehicle stability and control, and it is important to develop predictive models
and computational tools that address this problem. The objective of this article was to develop
a cohesive zone model for rubber to numerically predict crack growth in a rubber component
under dynamic tearing. The cohesive zone model for rubber was embedded into the material
constitutive equation via a user-defined material subroutine (VUMAT) of ABAQUS. It
consisted of three parts: (1) hyperviscoelastic behavior before damage, (2) damage initiation
based on the critical strain energy density, and (3) hyperviscoelastic behavior after damage
initiation. Crack growth in the tensile strip and pure shear specimens was simulated in
ABAQUS Explicit, and good agreement was reported between finite element analysis
predictions and test results
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Comparison of Analytical Model for Contact Mechanics Parameters with Numerical Analysis and Experimental Results
ABSTRACT Being able to estimate tire/rubber friction is very important to tire engineers, materials developers, and pavement engineers. This is because of the need for estimating forces generated at the contact, optimizing tire and vehicle performance, and estimating tire wear. Efficient models for contact area and interfacial separation are key for accurate prediction of friction coefficient. Based on the contact mechanics and surface roughness, various models were developed that can predict real area of contact and penetration depth/interfacial separation. In the present work, we intend to compare the analytical contact mechanics models using experimental results and numerical analysis. Nano-indentation experiments are performed on the rubber compound to obtain penetration depth data. A finite element model of a rubber block in contact with a rough surface was developed and validated using the nano-indentation experimental data. Results for different operating conditions obtained from the developed finite element model are compared with analytical model results, and further model improvements are discussed.
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- Award ID(s):
- 1650423
- PAR ID:
- 10390777
- Date Published:
- Journal Name:
- Tire Science and Technology
- Volume:
- 48
- Issue:
- 3
- ISSN:
- 0090-8657
- Page Range / eLocation ID:
- 168 to 187
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.2346/tire.19.180198
