EFFECTS OF PRECONDITIONING ON THE ELASTIC BEHAVIOR OF SKIN UNDER COMPRESSIVE LOADING

In physiological loading conditions, the skin tissues are, sometimes, loaded compressively. The mechanical characteristics of skins in tension have been studied intensively, while those in compression have not been studied thoroughly. Previous studies suggested that, in order to obtain repeatable mechanical parameters, the skin sample should be properly preconditioned in the tensile tests. The present study is to investigate if the skin sample should be preconditioned in the compressive tests. Pigskins were used in the present study. Compression tests were performed in confined and unconfined loading configurations and at four different loading speeds (0.5, 1.0, 40, and 400 mu m/s). Our results show that skin samples should be preconditioned in compressive tests, to obtain repeatable mechanical parameters. The necessary number of the loading cycles in the preconditioning treatment for compressive testing is less than that for tensile testing. Our findings indicate that the skin samples reach repeatable mechanical behavior after 3-4 loading cycles, independent of the loading rate and loading configurations (confined or unconfined compressions).