1. Reference problem

1.1. Geometry

This is a test on a cubic mesh with a side of \(1\) mm.

1.2. Material properties

The material obeys the law of visco-hyper-elastic behavior. The hyperelastic behavior is of the Neo-Hookean type. The visco-elastic behavior is given by a Prony series of order \(3\). The parameters of the law are:

\({\mathrm{\nu }}=0.495\)	Poisson’s ratio
\({\mathrm{C_{10}}}=0.30,{\mathrm{C_{01}}}=\mathrm{C_{02}}=\mathrm{C_{20}}=0\)	Long-term Mooney-Rivlin material parameters, i.e. for infinite behavior (MPa)
\({\mathrm{G}}=[1.33, 0.66, 0.33]\)	List of values of the long-term shear modulus of the Prony series of order 3 (MPa)
\({\mathrm{\tau}}=[100, 10000, 1000000]\)	List of relaxation time values from the Prony series of order 3 (s)

1.3. Boundary conditions and loads

Symmetry conditions are imposed on the \(3\) faces orthogonal to the \(3\) directions of the coordinate system.

A displacement of \(0.2\) mm is imposed on the stressed surface in \(1\) s in order to generate a nominal stress state of the order of \(1\) MPa. The load is held for \(10\) million seconds.