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Viscoelasticity

Viscoelasticity is modeled with n parallel group_materi_maxwell_chains. Each of the chains contains a spring with stiffness Em in line with a dash pot with relaxation time tm (m indicates the m-th maxwell chain). The viscoelastic stress rate is given by (with Cijklm is the elastic tensor modulus of the m-th maxwell chain (depending on Em and the poisson ratio))


\begin{displaymath}
\sum_{m=0}^{m=n-1} ( {C_{ijkl}}^m \dot{\epsilon_{kl}}^{\rm elas}
- \frac {{\sigma_{ij}}^m}{t^m} )
\end{displaymath}



root
1998-11-16