A HYPERELASTIC CONSTITUTIVE MODEL FOR SOFT BIOLOGICAL TISSUES CONSIDERING INDIVIDUAL ASPECTS
Ana Bárbara Krummenauer Formenton1; Jakson Manfredini Vassoler1
1 Universidade Federal do Rio Grande do Sul
doi:10.20906/CPS/CILAMCE2017-1181
Resumo
Soft biological tissues are composed mainly by collagen, elastin and ground substance. Due to their structural arrangement, the numerical representation of their mechanical behavior is a nontrivial subject. Moreover, the tissues mechanical behavior can change if taken from different individual or different position of the same individual. Many authors have found experimental evidences that qualitatively correlate the mechanical response of biological tissues with some of their characteristics through individual parameters. The individual parameters used in these works are related to physical, physiological, histological or pathological aspects. The quantification of such correlations can indicate which parameters may be used on material laws in order to improve the mechanical representation of the tissue for different individuals. Aiming to correlate the mechanical behavior of the biological tissue with individual parameters, the scope of the present work is to develop a material model capable to incorporate specific individual variables dependences. The proposed constitutive model is based on classical hiperelasticity, in which the individual parameter dependence is incorporated in energy potentials that modifies the constitutive relation. The individual parameters are taken as external material parameters making possible to employ classical hyperelastic models into the representation of the biological tissue. Numerical examples are presented evidencing the capability of the proposed model to represent the tissues mechanical behavior and the individual characteristics dependences.
Palavras-chave: Constitutive model; individual aspects; biological tissue