In this work, a constitutive framework for the mechanical characterization of soft biological tissues is proposed. Making use of the additive decomposition of the strain energy function, anisotropic and time-dependent behaviors are easily included into the model and can be switched on and off according to the particular tissue under investigation. Viscoelasticity enters the framework via an evolution equation, which is here solved using a higher-order diagonally implicit Runge–Kutta method. Improved accuracy and efficiency are achieved compared to the standard Backward–Euler scheme, the former measured by convergence order of the integration and the latter by the achievement of considerable speed-up factors. The proposed framework is shown to be capable of modeling a wide variety of different soft tissues, such as skin, tendon, colorectal tissue and brain white matter.

在这项工作中，提出了软生物组织力学表征的本构框架。利用应变能函数的加法分解，各向异性和时间相关的行为很容易包含在模型中，并且可以根据所研究的特定组织打开和关闭。粘弹性通过演化方程进入框架，此处使用高阶对角隐式 Runge-Kutta 方法求解。与标准的 Backward-Euler 方案相比，实现了更高的精度和效率，前者通过积分的收敛顺序来衡量，后者通过实现相当大的加速因子来衡量。所提出的框架被证明能够对各种不同的软组织进行建模，例如皮肤、肌腱、