Department of Industrial Engineering, University of Padova, Via G. Marzolo 8, 35131 Padova, Italy ; Centre of Mechanics of Biological Materials, University of Padova, Via G. Marzolo 9, 35131 Padova, Italy.
Centre of Mechanics of Biological Materials, University of Padova, Via G. Marzolo 9, 35131 Padova, Italy.
Comput Math Methods Med. 2014;2014:530242. doi: 10.1155/2014/530242. Epub 2014 Feb 20.
The attention is focused on the viscoelastic behavior of human plantar aponeurosis tissue. At this purpose, stress relaxation tests were developed on samples taken from the plantar aponeurosis of frozen adult donors with age ranging from 67 to 78 years, imposing three levels of strain in the physiological range (4%, 6%, and 8%) and observing stress decay for 240 s. A viscohyperelastic fiber-reinforced constitutive model with transverse isotropy was assumed to describe the time-dependent behavior of the aponeurotic tissue. This model is consistent with the structural conformation of the tissue where collagen fibers are mainly aligned with the proximal-distal direction. Constitutive model fitting to experimental data was made by implementing a stochastic-deterministic procedure. The stress relaxation was found close to 40%, independently of the level of strain applied. The agreement between experimental data and numerical results confirms the suitability of the constitutive model to describe the viscoelastic behaviour of the plantar aponeurosis.
研究聚焦于人体足底筋膜组织的黏弹性行为。为此，对年龄在 67 至 78 岁的冷冻成年供体的足底筋膜组织样本进行了应力松弛测试，在生理范围内施加了三个应变水平（4%、6%和 8%），并观察了 240 秒的应力衰减。假设黏超弹性纤维增强各向异性本构模型来描述筋膜组织的时变行为。该模型与组织的结构构象一致，其中胶原纤维主要沿近-远方向排列。通过实施随机-确定性程序来拟合本构模型与实验数据。无论施加的应变水平如何，应力松弛都接近 40%。实验数据与数值结果之间的一致性证实了本构模型适用于描述足底筋膜的黏弹性行为。
