Mechanics of Time-Dependent Materials

, Volume 10, Issue 2, pp 125–133 | Cite as

Determination of the relaxation modulus of a linearly viscoelastic material

  • Joonas Sorvari
  • Matti Malinen


In this paper, a numerical method for computing the relaxation modulus of a linearly viscoelastic material is presented. The method is valid for relaxation tests where a constant strain rate is followed by a constant strain. The method is similar to the procedure suggested by Zapas and Phillips. Unlike Zapas-Phillips approach, this new method can be also applied for times shorter than t 1/2, where t 1 denotes time when the maximum strain is achieved. Therefore this method is very suitable for materials that experiences fast relaxation. The method is verified with numerical simulations. Results from the simulations are compared with analytical solution and Zapas-Phillips method. Results indicate that the presented approach is suitable for estimating the relaxation modulus.


Numerical algorithm Relaxation test Finite ramp time Relaxation modulus Linear viscoelasticity 


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Copyright information

© Springer Science+Business Media B.V. 2006

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of KuopioKuopioFinland

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