Biomechanics Laboratory of Physical Education Institute, Inner Mongolia Normal University, Hohhot, 010022, People's Republic of China.
College of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot, 010022, People's Republic of China.
Theory Biosci. 2022 Feb;141(1):13-25. doi: 10.1007/s12064-021-00361-7. Epub 2022 Feb 3.
A quaternary viscoelastic structure model with two characteristic times is presented to describe the viscoelastic properties of parallel-fibered collagen tissue. The comparison results of model prediction and experimental data of rabbit medial collateral ligaments show that the model could accurately describe viscoelastic behavior such as stress-relaxation, strain-strengthening and creep of bio-soft-tissue within a small scope of errors. To study the biomechanical mechanism of viscoelasticity that biological soft tissue shows, the influence of model parameters on viscoelastic behavior of bio-soft-tissue is analyzed and researched, which indicated that the major influential elements of stress-relaxation in bio-soft-tissue are elastic modulus, relaxation time and strain rate of proteoglycan-rich matrix. The influence of elastic modulus of collagen fibers on stress-relaxation is not significant. However, the nonlinearity of stress-strain curve and viscoelastic behavior of bio-soft-tissue mostly depends on recruitment and reorientation of collagen fibers under external loading.
本文提出了一种具有两个特征时间的四元黏弹性结构模型，用于描述平行纤维胶原组织的黏弹性性质。模型预测与兔内侧副韧带实验数据的对比结果表明，该模型可以在较小误差范围内准确描述生物软组织的黏弹性行为，如应力松弛、应变强化和蠕变。为了研究生物软组织黏弹性的生物力学机制，分析和研究了模型参数对生物软组织黏弹性行为的影响，结果表明，影响生物软组织内应力松弛的主要因素是糖胺聚糖丰富基质的弹性模量、松弛时间和应变速率。胶原纤维弹性模量对其应力松弛的影响并不显著。然而，生物软组织的应力-应变曲线的非线性和黏弹性行为主要取决于在外载作用下胶原纤维的募集和重定向。
