532 顕著な残留ひずみを有する大動脈壁の応力解析(計算バイオメカニクス3,OS25 計算バイオメカニクス)

Abstract

We carried out stress analysis on the rabbit thoracic aorta which has residual strain as defined by the opening angle of a radially cut ring specimen, taking account of two types of boundary conditions in the longitudinal directions during a release of the residual stress: a constant longitudinal stretch and zero longitudinal stress. For the cases of various opening angles, 0, 100, 200 and 300 degrees, and the two types of boundary conditions mentioned above, we determined the geometry in the stress-free state and the material constants in an incompressible isotropic hyperelastic material model to fit the same unloaded geometry and the same pressure-diameter relationship under a constant longitudinal length and intraluminal pressure (0-20kPa). The results indicate that appropriate boundary conditions should be taken into account during the release of residual stress to obtain the stress distributions in the physiologically loaded state especially for the vessel with a large residual strain.