基于混合物理论的骨组织应力松弛效应分析

目的 研究骨组织在给定位移下的应力松弛响应，为骨组织粘弹性性质实验研究提供参考。方法 引入基于混合物理论的现代多孔介质模型来研究骨组织在外界刺激下的流固耦合效应，采用Laplace变换技术求解控制方程。结果 得出了一维应力松弛解析结果，算例与实验结果进行了比较。结论 松质骨呈现的表观粘弹性行为以及能量耗散性质与松质骨中流体组分的扩散和流动之间具有很大的相关性。

ANALYSIS OF STRESS RELAXATION BEHAVIOR OF BONE TISSUE BASED ON THE MIXTURE THEORY

Objective To investigate the stress relaxation response of bony tissue under constant displacement loading. Methods A modern porous medium model was developed to do the research on the mechanical behavior of fluid saturated living bone tissue based on the mixture theory by using the Laplace transform technique. Results A one dimensional governing equation is derived for the case of a linear poroelastic solid skeleton saturated with viscid bony fluid. The result shows that the bone tissue is provided with certain features similar to those appearing in viscoelastic solids, which means the responses do not only depend on time, but also depend on previous loading history. Conclusion Viscoelastic behavior and energy dissipation of cancellous bone are depended on the flow and diffusion rate of the fluid composition in bone.