基于CT图像的沥青混合料剪切疲劳破坏

Shear fatigue damage of asphalt mixture based on CT image processing

利用工业CT得到沥青混合料疲劳剪切破坏前后的微观图像,再运用数字图像处理技术分析破坏前后不同试件内部各层面孔隙率、CT数的变化,得到损伤变量的变化规律,并进行了损伤分形演化分析。研究结果表明,试件剪切破坏多发生在其初始空隙分布较密集处,空隙率越大处破坏越严重,CT数的变化与空隙率变化规律相对应;损伤越严重,测算出的损伤变量也越大,损伤变量呈"中间大、两头小"的趋势;沥青混合料剪切疲劳破坏前后过程是分形的。

The industrial CT scanner is used to get internal microscopic images of the asphalt mixture fatigue shear failure before and after test, combined with digital image processing technology to analyzes porosity and CT numbers changes between the different internal of the specimens before and after the destruction of all levels, to get the damage variable and performed fractal damage evolution analysis. The results show that the shear failure of the specimen occurred in the gap which initial distribution is more densely. The larger the po- rosity, the more serious damage, changes in porosity variation correspond to the number of CT. The more serious damage, estimated the damage variable is greater, the trend of the damage variable was ＂big in the middle, two small＂. Before and after the asphalt shear fa- tigue failure process is fractal.