Leng Xiaochang, Chen Xin, Deng Xiaomin, Sutton Michael A, Lessner Susan M
Department of Mechanical Engineering, University of South Carolina, Columbia, SC, 29208, USA.
Department of Cell Biology & Anatomy, University of South Carolina, Columbia, SC, 29208, USA.
Ann Biomed Eng. 2015 Dec;43(12):2838-51. doi: 10.1007/s10439-015-1357-9. Epub 2015 Jun 23.
A cohesive zone model (CZM) approach is applied to simulate atherosclerotic plaque delamination experiments in mouse abdominal aorta specimens. A three-dimensional finite element model is developed for the experiments. The aortic wall is treated as a fiber-reinforced, highly deformable, incompressible material, and the Holzapfel-Gasser-Ogden (HGO) model is adopted for the aortic bulk material behavior. Cohesive elements are placed along the plaque-media interface along which delamination occurs. The 3D specimen geometry is created based on images from the experiments and certain simplifying approximations. A set of HGO and CZM parameter values is determined based on values suggested in the literature and through matching simulation predictions of the load vs. load-point displacement curve with experimental measurements for one loading-delamination-unloading cycle. Using this set of parameter values, simulation predictions for four other loading-delamination-unloading cycles are obtained, which show good agreement with experimental measurements. The findings of the current study demonstrate the applicability of the CZM approach in arterial tissue failure simulations.
采用内聚区模型(CZM)方法模拟小鼠腹主动脉标本中的动脉粥样硬化斑块分层实验。针对这些实验建立了三维有限元模型。主动脉壁被视为纤维增强、高变形性、不可压缩材料,并采用霍尔扎菲尔 - 加塞尔 - 奥格登(HGO)模型描述主动脉主体材料的行为。在内聚单元沿发生分层的斑块 - 中膜界面放置。基于实验图像并通过某些简化近似创建三维标本几何形状。根据文献中建议的值,并通过将载荷与载荷点位移曲线的模拟预测与一个加载 - 分层 - 卸载循环的实验测量值进行匹配,确定了一组HGO和CZM参数值。使用这组参数值,获得了其他四个加载 - 分层 - 卸载循环的模拟预测结果,这些结果与实验测量值显示出良好的一致性。当前研究结果证明了CZM方法在动脉组织失效模拟中的适用性。