title: Constitutive modeling of stress softening and permanent set in a porcine skin tissue: Impact of the storage preservation.
abstract: Prior to testing, soft tissues are usually maintained in different media and additives (solution, air, cryopreservant…) under various environment conditions (temperature, storage duration….). In many cases, results from mechanical tests performed on these stored tissues are supposed to be as closed as possible to the fresh ones. In the present work, cyclic tensile tests were performed with increasing values of strain on porcine skin tissues (excised following the Langer's lines) to enhance tissues mechanical nonlinearity such as softening behavior and permanent set. Optical methods were used to follow the in-plane strains evolution. These latest values were used as data to simulate the structural behavior of these heterogeneous materials. The numerical simulation is based on the constitutive pseudo-elastic model accounting for the softening behavior as well as the permanent set. As a result, reliable material parameters were extracted from the experiments/model comparison for each storage solution. The result of this study reveals that preservation conditions must be carefully chosen: at low strain the tissues store in fridge in a saline solution during a short time, or in freezer (-80°C) in water with cryopreservant and the fresh one lead to a similar mechanical response. For larger strain, the freezing (-80°C) in water with cryopreservant is the only procedure for which the tissue recovers its initial behavior.
authors.affiliation: C2MA, Ecole des Mines d'Alès, Alès, France. Electronic address: Anne-Sophie.Caro@mines-ales.fr.
authors.forename: A S
authors.initials: AS
authors.lastname: Caro-Bretelle
authors.affiliation: C2MA, Ecole des Mines d'Alès, Alès, France.
authors.forename: P
authors.initials: P
authors.lastname: Ienny
authors.affiliation: C2MA, Ecole des Mines d'Alès, Alès, France.
authors.forename: R
authors.initials: R
authors.lastname: Leger
authors.affiliation: C2MA, Ecole des Mines d'Alès, Alès, France.
authors.forename: S
authors.initials: S
authors.lastname: Corn
authors.affiliation: LGEI, Ecole des Mines d'Alès, Alès, France.
authors.forename: I
authors.initials: I
authors.lastname: Bazin
authors.affiliation: Aix-Marseille Université, Unité de Recherche sur les Maladies Infectieuses Tropicales et Emergentes, UM63, CNRS 7278, IRD 198, INSERM 1095, Marseille, France.
authors.forename: F
authors.initials: F
authors.lastname: Bretelle
mesh_terms: D000818:Animals; D015925:Cryopreservation; D008422:Materials Testing; D015233:Models, Statistical; D017711:Nonlinear Dynamics; D012867:Skin / Q000166:cytology*; D013314:Stress, Mechanical; D013552:Swine; D013718:Tensile Strength
keywords: Digital Image Correlation; Permanent set; Porcine skin; Pseudo-elasticity; Sample preservation; Stress softening