Compressibility of arterial wall in ring-cutting experiments.
It is common practice in the arterial wall modeling to assume material incompressibility. This assumption is driven by the observation of the global volume preservation of the artery specimens in some mechanical loading experiments. The global volume preservation, however, does not necessarily imply the local volume preservation - incompressibility. In this work, we suggest to use the arterial ring- cutting experiments for the assessment of the local incompressibility assumption. The idea is to track the local stretches of the marked segments of the arterial ring after the stress-relieving cut. In the particular case of the rabbit thoracic artery, considered in this work, the following criteria for radial stretches come from preliminary analysis. If after the radial cut the marked segments shorten at the inner surface of the wall and lengthen at the outer surface while remaining unchanged in the middle of the wall then material is locally incompressible. If, however, the marked segments remain unchanged at the surfaces while lengthening in the middle of the wall then the material is locally compressible. Any other scenario would be an indication of the improper modeling assumptions, i.e. residual stresses are not relieved or material constants are inaccurate etc. It is believed that the proposed approach can be successfully implemented in experiments shedding new light on the arterial incompressibility issue.
Volokh
K Y
KY
On leave of absence from the Technion, Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles St, Baltimore, MD 21218, USA. kvolokh@jhu.edu
D000818:Animals; D004548:Elasticity; D008954:Models, Biological; D011817:Rabbits; D013314:Stress, Mechanical; D013895:Thoracic Arteries / Q000502:physiology*