粗集料骨架间隙率VCAmix是沥青混合料试件的重要体积参数之一.应用数字图像处理技术,采用红色石料作为粗集料,普通石料作为细集料,利用颜色的对比精确区分粗、细集料;进一步对试件做薄片切割,采用概率统计理论,推导了由多幅二维截面图像上的粗集料面积比计算三维空间中粗集料体积比的方法;并对如何确定薄片数量,及其与保证率之间的关系做出了说明和验证.结果显示,40片薄片能够满足工程精度要求.
Voids in coarse aggregate of asphalt mixtures(VCAmix)is one of the most important volumetric properties of asphalt mixtures.Digital image processing technique is adopted to distinguish the coarse and fine aggregate with red stones as coarse aggregates and common stones as fine aggregates.Further more,the specimen is cut into slices and probability statistics theory is used to put forward a method that calculating the coarse aggregate's volume distribution in 3D space from its area distribution in 2D section.At last,how to determine the number of slices and the relation between slices and the guarantee rate is introduced.Results show 40 slices can satisfy the requirement of engineering accuracy.