Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.jmbbm.2015.11.027
Title (Primary) Control of tension–compression asymmetry in Ogden hyperelasticity with application to soft tissue modelling
Author Moerman, K.M.; Simms, C.K.; Nagel, T.
Source Titel Journal of the Mechanical Behavior of Biomedical Materials
Year 2016
Department ENVINF
Volume 56
Page From 218
Page To 228
Language englisch
Keywords Hyperelasticity; Tension–compression asymmetry; Symmetry; Ogden; Constitutive equations
UFZ wide themes RU5;
Abstract This paper discusses tension–compression asymmetry properties of Ogden hyperelastic formulations. It is shown that if all negative or all positive Ogden coefficients are used, tension–compression asymmetry occurs the degree of which cannot be separately controlled from the degree of non-linearity. A simple hybrid form is therefore proposed providing separate control over the tension–compression asymmetry. It is demonstrated how this form relates to a newly introduced generalised strain tensor class which encompasses both the tension–compression asymmetric Seth–Hill strain class and the tension–compression symmetric Bažant strain class. If the control parameter is set to q = 0.5 a tension–compression symmetric form involving Bažant strains is obtained with the property Ψ(λ12, λ3) = Ψ(1/λ1, 1/λ2, 1/λ3). The symmetric form may be desirable for the definition of ground matrix contributions in soft tissue modelling allowing all deviation from the symmetry to stem solely from fibrous reinforcement. Such an application is also presented demonstrating the use of the proposed formulation in the modelling of the non-linear elastic and transversely isotropic behaviour of skeletal muscle tissue in compression (the model implementation and fitting procedure have been made freely available). The presented hyperelastic formulations may aid researchers in independently controlling the degree of tension–compression asymmetry from the degree of non-linearity, and in the case of anisotropic materials may assist in determining the role played by, either the ground matrix, or the fibrous reinforcing structures, in generating asymmetry.    
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=16987
Moerman, K.M., Simms, C.K., Nagel, T. (2016):
Control of tension–compression asymmetry in Ogden hyperelasticity with application to soft tissue modelling
J. Mech. Behav. Biomed. Mater. 56 , 218 - 228 10.1016/j.jmbbm.2015.11.027