Depth-dependent strain fields of articular cartilage under rolling load by the optimized digital image correlation technique.
Depth-dependent strain fields of articular cartilage under rolling load by the optimized digital image correlation technique.
复制标题
DOI：
10.1016/j.msec.2013.01.054
复制
发表时间：
2013-05
期刊：
影响因子：
--
通讯作者：
Li-Lan Gao;Chunqiu Zhang;Yu‐Bo Yang;J. Shi;Yun-Wei Jia
中科院分区：
文献类型：
--
作者：
Li-Lan Gao;Chunqiu Zhang;Yu‐Bo Yang;J. Shi;Yun-Wei Jia
关节软骨在日常生活中会发生较大的滚动，研究滚动载荷下关节软骨的深度相关力学行为具有重要意义。首次采用优化的数字图像相关技术对关节软骨进行滚动实验，分析了软骨的法向应变和切向应变随深度的变化规律。结果表明，随着轧制时间的延长，各层的法向应变和剪应变先增大后减小，随压应变的增大而增大。在恒定的压应变下，法向应变和剪应变值沿着软骨深度减小。不同规格化深度的法向应变值随着轧制速度的增加而减小。随着轧制速度的增加，表层和中间层的剪切应变值减小，而深层的剪切应变值变化不大。随着轧制次数的增加，不同轧制时间下的法向应变值增加，从第1次到第99次，初始法向应变增加了30.6%。考虑压应变和轧制速率的影响，得到了法向应变与归一化深度的拟合关系，拟合曲线与实验结果吻合较好。
It is significant to investigate the depth-dependent mechanical behaviors of articular cartilage under rolling load since considerable rolling occurs for cartilage joint in activities of daily living. In this study, the rolling experiments of articular cartilage were conducted by applying an optimized digital image correlation (DIC) technique for the first time and the depth-dependent normal strain and shear strain of cartilage were analyzed. It is found that the normal strain and shear strain values of different layers increase firstly and then decrease with rolling time, and they increase with increasing compressive strains. The normal strain and shear strain values decrease along cartilage depth with constant compressive strain. The normal strain values of different normalized depth decrease with increasing rolling rates. The shear strain values of superficial layer and middle layer decrease; however there are no major changes for the shear strain values of deep layer with increasing rolling rates. The normal strain values with different rolling time increase with increasing rolling numbers and the 30.6% increase in initial normal strain is observed from 1st to 99th cycle. The fitting relationship of the normal strain and normalized depth was obtained considering the effects of compressive strain and rolling rate and the fitting curves agree with the experimental results for cartilage very well.