Structural damage models for fibrous biological soft tissues

Abstract

This paper presents a comparison between deterministic and stochastically based three-dimensional finite-strain damage models for fibrous biological soft tissues, accounting for separate contributions on damage for the matrix and the fibers. Both models are compared in terms of their numerical performance and qualitative predictions under different loading conditions. Continuum damage mechanics is used to describe the softening behavior of soft tissues under large deformation, making use of the concept of internal variables which provides a very general description of materials involving irreversible effects. In the stochastic model, statistical aspects related to the distribution of fiber length lead to the strain-driven damage model for the fibrous part. Simulations of a uniaxial test, a hollowed plate under biaxial displacement control, and a 3D simulation of a coronary artery undergoing balloon angioplasty are used to compare the performance of both models. Numerical simulations indicate that both models provide similar predictions of damage.