An elasto-viscoplastic model to describe the ratcheting behavior of articular cartilage

作者：Zhu, Yilin^*

来源：Biomechanics and Modeling in Mechanobiology, 2018, 17(6): 1875-1883.

DOI：10.1007/s10237-018-1062-3

• Articular cartilage
• Constitutive model
• Logarithmic stress rate
• Ratcheting

In the present work, a constitutive model for articular cartilage is proposed in finite elasto-viscoplasticity. For simplification, articular cartilage is supposed to be a typical composite composed of a soft basis and a fiber assembly. The stress tensor and free energy function are hence accordingly divided into two components. The high nonlinear stress-strain response is assumed to be mainly related to the fiber assembly and described by an exponential-type hypoelastic relation. Ratcheting is considered according to the viscoplasticity, the evolution rule of which is deduced from the dissipative inequality by the co-directionality hypotheses. Then, the capability of the proposed model is validated by comparing its predictions with related experimental observations. Results show that the ratcheting behavior and stress-strain hysteresis loops are reasonably captured by the proposed model.

• 出版日期2018-12
• 单位烟台大学; 成都大学