基于CT断层扫描图像的混凝土粗集料三维虚拟筛分

分析了基于数字图像进行混凝土级配分析的主流方法的局限性,并说明了采用工业CT技术手段的独特优势。按照沥青混合料粗集料分级粒径范围制作了5个试件,利用工业CT扫描获取粗集料体积参数。对3类集料体积数字计算方法的准确性进行了比较。通过球面调和变换表征粗颗粒的三维表面轮廓,并在此基础上获取L、W维度位置,并截取出通过筛孔控制平面。经过一系列数字图像处理手段,最终判定集料所能通过的方孔筛的筛孔大小。验证结果表明,基于CT断层扫描图片可以较准确地实现混凝土粗集料的三维虚拟筛分。

3-dimensional virtual sieve of concrete based analysis of coarse aggregate on CT scan image

The limitations of the mainstream method for the sieve analysis based on the digital image processing were analyzed and the advantages of industrial X-ray CT technique were pointed out.5 specimens were produced according to the coarse aggregate size range of asphalt mixture.The volumetric parameters of the coarse aggregate were obtained by industrial CT scanning.The accuracies of the 3 methods for calculating the volumetric parameters were compared.The 3-dimensional surface contours were characterized by the spherical harmonic transformation,thus the L,W dimension positions were got,and the control planes passing the sieve were intercepted.The size of the square sieve that the aggregate particle can pass was determined by a series of digital image processing techniques.The validation results show that by means of the new method based on CT scan images the 3-dimensional virtual sieve analysis of the coarse aggregate could be realized more accurately.