Dataset Information

Stress heterogeneities in sheared type-I collagen networks revealed by Boundary Stress Microscopy.

ABSTRACT: Disordered fiber networks provide structural support to a wide range of important materials, and the combination of spatial and dynamic complexity may produce large inhomogeneities in mechanical properties, an effect that is largely unexplored experimentally. In this work, we introduce Boundary Stress Microscopy to quantify the non-uniform surface stresses in sheared collagen gels. We find local stresses exceeding average stresses by an order of magnitude, with variations over length scales much larger than the network mesh size. The strain stiffening behavior observed over a wide range of network mesh sizes can be parameterized by a single characteristic strain and associated stress, which describes both the strain stiffening regime and network yielding. The characteristic stress is approximately proportional to network density, but the peak boundary stress at both the characteristic strain and at yielding are remarkably insensitive to concentration.

SUBMITTER: Arevalo RC

PROVIDER: S-EPMC4348423 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Stress heterogeneities in sheared type-I collagen networks revealed by Boundary Stress Microscopy.

Arevalo Richard C RC Kumar Pramukta P Urbach Jeffrey S JS Blair Daniel L DL

PloS one 20150303 3

Disordered fiber networks provide structural support to a wide range of important materials, and the combination of spatial and dynamic complexity may produce large inhomogeneities in mechanical properties, an effect that is largely unexplored experimentally. In this work, we introduce Boundary Stress Microscopy to quantify the non-uniform surface stresses in sheared collagen gels. We find local stresses exceeding average stresses by an order of magnitude, with variations over length scales much ...[more]

PMID: 25734484

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Dataset Information

Stress heterogeneities in sheared type-I collagen networks revealed by Boundary Stress Microscopy.

Publications

Stress heterogeneities in sheared type-I collagen networks revealed by Boundary Stress Microscopy.

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