Bladder tissue biomechanical behavior: Experimental tests and constitutive formulation
Bladder tissue biomechanical behavior: Experimental tests and constitutive formulation
复制标题
DOI：
10.1016/j.jbiomech.2015.07.021
复制
发表时间：
2015-09-18
影响因子：
2.4
通讯作者：
Zanetti, E. M.
中科院分区：
文献类型：
--
作者：
Natali, A. N.;Audenino, A. L.;Zanetti, E. M.
采用实验和计算相结合的方法，给出了膀胱组织力学行为的本构分析方法。第一步是设计和开发猪膀胱标本的力学测试。考虑到组织纤维成分的分布，膀胱已经被采集，并在沿优先方向以不同应变率进行了单轴循环试验。实验结果表明，纤维沿择优方向分布的组织构象及其与基质的相互作用使材料表现出各向异性、非线性和随时间变化的应力-应变行为。详细地说，实验数据显示，沿横向有较大的组织硬度。通过应力-应变曲线的应变率相关性和滞回现象来评价材料的粘性。第二步是根据膀胱组织的结构形态和实验结果，建立特定的纤维增强粘超弹性本构模型。通过最小化模型和实验数据之间的偏差来识别本构参数。实验结果和模型结果之间的一致性代表了通过所提出的操作程序来评估本构模型的可靠性的术语。(C)2015爱思唯尔有限公司。保留所有权利。
A procedure for the constitutive analysis of bladder tissues mechanical behavior is provided, by using a coupled experimental and computational approach. The first step pertains to the design and development of mechanical tests on specimens from porcine bladders. The bladders have been harvested, and the specimens have been subjected to uniaxial cyclic tests at different strain rates along preferential directions, considering the distribution of tissue fibrous components. Experimental results showed the anisotropic, non-linear and time-dependent stress-strain behavior, due to tissue conformation with fibers distributed along preferential directions and their interaction phenomena with ground substance. In detail, experimental data showed a greater tissue stiffness along transversal direction. Viscous behavior was assessed by strain rate dependence of stress-strain curves and hysteretic phenomena. The second step pertains the development of a specific fiber-reinforced visco-hyperelastic constitutive model, in the light of bladder tissues structural conformation and experimental results. Constitutive parameters have been identified by minimizing the discrepancy between model and experimental data. The agreement between experimental and model results represent a term for evaluating the reliability of the constitutive models by means of the proposed operational procedure. (C) 2015 Elsevier Ltd. All rights reserved.