基于数字图像分析的豆砾石形态特征量化研究

护盾式TBM施工过程中，围岩和管片之间会形成一个环形空隙，豆砾石是该环形空隙填充的主要材料，开展豆砾石形态特征量化研究对其材料特性研究具有重要意义。试验选用人工碎石和天然卵石4种豆砾石样本，采用数字图像分析与筛分试验相结合的方式研究。试验成果首先从颗粒的轮廓形态、棱角形态以及粒径3个方面获取了6个颗粒形态定量指标，然后通过体积加权获取豆砾石样本的形态特征量化指标，最后将图像分析结果与筛分试验结果对比，验证图像分析结果的可靠性。研究结果表明，借助数字图像分析，可快速、有效地获取表征豆砾石形态特征的定量指标，进而为TBM工程中豆砾石筛选及质量控制提供依据。

Quantification Research on Morphological Characteristics of Pea Gravel Based on Digital Image Processing

In the process of shield TBM construction, an annular gap will be formed between the surrounding rock and the segment, and pea gravel is the main material to fill the annular gap. It is of great significance to carry out quantitative research on the morphological characteristics of pea gravel for its material properties. The test is carried out with four kinds of pea gravel samples, including artificial gravel and natural pebble, combined with digital image analysis and particle size analysis. To analyze the test results, six quantitative indicators of particle morphology from three aspects of the contour shape, angular shape, and particle size were firstly obtained, and then the quantitative indexes were used to describe the morphological characteristics of the pea gravel samples. Finally, the image analysis results and the particle size analysis results were compared to verify the reliability of the image analysis results. The research results show that with the help of digital image analysis, the quantitative indexes of the morphological characteristics of pea gravel can be obtained quickly and effectively, which provides a basis for the screening and quality control of pea gravel in TBM constructed project.