The biomechanical properties of canine skin measured in situ by uniaxial extension
Résumé
A uniaxial extension system was setup to analyze the mechanical properties of dog skin. Material and methods: Pads were glued onto dog skin with constant reproducible geometrical parameters and the extension force was measured as a function of the extension values. Forty-one sites (82 cycling tests) were investigated in situ on 11 canine cadavers, half of them after surgically isolating the test area from the surrounding skin. Series of loading-unloading cycles of up to 5 N or 10 N or both loads were performed on each site. The elastic properties and the dissipative effects were characterized respectively by evaluating the secant Rigidity at maximum loads and the Fraction of dissipated energy. Results: A hysteresis phenomenon, implying the need for preconditioning to attain equilibrium cycles, was apparent during mechanical characterization. Polynomial expressions were used to relate the measured Rigidities and the Fractions of dissipated energy with or without sample isolation. The latter were less affected by isolation. The ratios between the Rigidities at 5 N to those at 10 N displayed non-linearity in the investigated extension range in contrary to the Fractions of dissipated energy.