粗集料数字化三维实形特征及其分布

Digital 3D morphological features and distribution of asphalt coarse aggregate

关键词:  混合料  集料  数字化技术  实形重构  形貌参数  道路工程  特征分布

Key words:  asphalt mixture  coarse aggregate  digital technology  geometric reconstruction  morphological feature parameters  road engineering  characteristic distribution

摘要:

为准确分析混合料中集料的形貌特征及其分布属性,更全面、深入和具体地认识集料,采用CT扫描、数字图像处理和三维几何重构技术相关数字化技术对集料颗粒进行实形重构,提出集料的5种形貌特征参数,针对3种集料的形貌特征进行数字化评价与试验分析,验证数字化重构方法的准确性,分析集料颗粒形貌分布特征,基于Pearson相关性方法分析形貌参数的相关性。结果表明:采用CT扫描技术和数字化实形重构技术,可以准确地还原集料颗粒的形貌特征,准确获得形貌参数；同种集料的不同粒径的形貌特征存在显著的分布特征；不同粒径的三维针片状指数和三维纹理指数相差不大；不同粒径范围的集料颗粒的形貌参数值随着粒径的增大离散性降低；三维纹理指数整体服从幂律分布,随粒径的增大,复杂程度逐渐降低；随粒径的增大,三维棱角度逐渐趋于稳定；三维棱角度与实形矩体度、实形球形度存在较强的负相关性；而实形球形度与三维纹理指数存在较强的正相关关系。数字化三维重构能准确、完整地描述和分析集料形貌及其分布特征。

Abstract:

In order to accurately analyze the morphological characteristics and distribution properties of aggregates in the mixture, and to have a more comprehensive, in-depth, and specific understanding of aggregates, CT scanning, digital image processing, and three-dimensional geometric reconstruction technologies were used to reconstruct the real shape of aggregate particles. Five morphological characteristic parameters of aggregates were proposed, and a digital evaluation and experimental analysis were conducted on the morphological characteristics of three aggregates. The accuracy of the digital reconstruction method was validated and the morphological distribution characteristics of aggregate particles were analyzed. Additionally, the Pearson correlation method was utilized to analyze the correlations among the morphological parameters. The study demonstrates that the use of CT scanning technology and digital reconstruction technology can accurately restore the morphological characteristics of aggregate particles and obtain morphological parameters. There are significant distribution characteristics of the morphology of different particle sizes of the same aggregate. The three-dimensional needle-like index and three-dimensional texture index show little variation across different particle sizes. As the particle size increases, the variability of the morphology parameter values for aggregates decreases. The overall three-dimensional texture index follows a power-law distribution, and the complexity gradually decreases with the increase of particle size. Additionally, as the particle size increases, the three-dimensional edge angle gradually stabilizes. There is a strong negative correlation between three-dimensional edge angle and solid moment degree, as well as between solid sphericity and three-dimensional edge angle. Conversely, there is a strong positive correlation between sphericity of the actual shape and the three-dimensional texture index. Digital 3D reconstruction can accurately and comprehensively describes and analyzes the morphology and distribution characteristics of aggregates.