Related Experiment Video
Updated: Aug 14, 2026

Controlled Strain of 3D Hydrogels under Live Microscopy Imaging
Published on: December 4, 2020
A polyconvex anisotropic strain-energy function for soft collagenous tissues
M Itskov1, A E Ehret, D Mavrilas
1Department of Continuum Mechanics, RWTH Aachen University, Eilfschornsteinstr. 18, 52062 Aachen, Germany. itskov@km.rwth-aachen.de
Abstract:
Polyconvexity of a strain-energy function is a very important mathematical condition, especially in the context of a boundary-value problem. In the present paper, we propose an exponential polyconvex anisotropic strain-energy function. It is given by a series with an arbitrary number of terms and associated material constants. Each term of this series a priori satisfies the condition of the energy- and stress-free natural state so that no additional restrictions have to be imposed. Due to the exponential form, the proposed hyperelastic model is suitable for soft biological tissues. Thus, a good agreement with experimental data on different types of tissues is achieved.
Related Concept Videos
Elastic Strain Energy for Normal Stresses
If...
Elastic Strain Energy for Shearing Stresses
Generalized Hooke's Law
Strain-Energy Density
In the elastic region of a material, the relationship between the stress and the strain is linear and follows Hooke's Law. The strain energy density in this region...
Hooke's Law
Strain Energy
Consider a rod that is fixed at one end and subjected to an axial force at the free end. This axial force induces stress within the rod, leading to its elongation. As the axial force increases, so does the elongation of the rod, illustrating a direct relationship between the force applied and the resulting...

