Finite Element Modeling of Entangled Collagen Fiber Gels With Randomly Oriented Fibers

Collagen is an important structural protein in the human body, and its molecules form structural aggregates at multiple length scales (i.e., microfibrils, fibrils, fibers, and bundles of different sizes) in biological tissues and organs [1]. The mechanical properties of most tissues are dependent on the underlying network of collagen fibers, proteoglycans, and other extracellular matrix components [2]. Similarly, the properties of in vitro tissue analogs, often created from collagen or fibrin gels, are also dependent on the organization of the biopolymers [3]. The overall mechanical response is intrinsically multi-scale and dynamic in both materials. As a result, a satisfactory description of the microstructure is important for exploring the essential physics of the tissue.