Annals of Biomedical Engineering

, Volume 37, Issue 6, pp 1117–1130 | Cite as

A Constitutive Model of Soft Tissue: From Nanoscale Collagen to Tissue Continuum

Article

Abstract

Soft collagenous tissue features many hierarchies of structure, starting from tropocollagen molecules that form fibrils, and proceeding to a bundle of fibrils that form fibers. Here we report the development of an atomistically informed continuum model of collagenous tissue. Results from full atomistic and molecular modeling are linked with a continuum theory of a fiber-reinforced composite, handshaking the fibril scale to the fiber and continuum scale in a hierarchical multi-scale simulation approach. Our model enables us to study the continuum-level response of the tissue as a function of cross-link density, making a link between nanoscale collagen features and material properties at larger tissue scales. The results illustrate a strong dependence of the continuum response as a function of nanoscopic structural features, providing evidence for the notion that the molecular basis for protein materials is important in defining their larger-scale mechanical properties.

Keywords

Multi-scale model Collagen Soft tissue Molecular mechanics Continuum Finite element Deformation Failure Mechanical properties 

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Copyright information

© Biomedical Engineering Society 2009

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringNorthwestern UniversityEvanstonUSA
  2. 2.Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridgeUSA
  3. 3.King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia

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