花岗岩残积土大孔隙结构定量表征

阙云; 蔡沛辰; 李显

doi:10.11988/ckyyb.20200987

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长江科学院院报 ›› 2022, Vol. 39 ›› Issue (2) : 82-88. DOI: 10.11988/ckyyb.20200987

岩土工程

花岗岩残积土大孔隙结构定量表征

阙云, 蔡沛辰, 李显

作者信息 +

Quantitative Characterization of Macropore Structure of Granite Residual Soil

QUE Yun, CAI Pei-chen, LI Xian

Author information +

文章历史 +

摘要

为揭示花岗岩残积土大孔隙结构的分布规律和形状特征,选取福州某地原状花岗岩残积土作为研究对象,基于工业CT扫描和ImageJ软件,定量化研究了大孔隙的成圆率、扁平度、整体轮廓系数、分形维数等参数分布规律。结果表明:约有80%以上的大孔隙直径在0.15~1 mm范围内,不到20%的大孔隙直径>1 mm。花岗岩残积土的大孔隙率介于5.8%~22.7%之间,且随着深度的增加呈先增大后减小趋势。大孔隙直径越大,孔隙成圆度越差。4个试样的整体轮廓系数变化范围在0.81~0.87之间,且孔隙整体轮廓系数随着土壤深度的增加变化较小。花岗岩残积土大孔隙率与分形维数存在一定的相关性,但不同试样的大孔隙率与分形维数的相关系数存在较大差异。综上,花岗岩残积土具有孔隙比大、粗糙程度差、大孔隙分布广泛、孔隙结构差异性大及局部孔隙扁平度离散性大等特点。

Abstract

In order to reveal the distribution law and shape characteristics of the macropore structure of granite residual soil, we quantified the round ratio, flatness, overall silhouette coefficient and fractal dimension of undisturbed granite residual soil in Fuzhou by using industrial CT scanning and ImageJ software. Our findings revealed that 1) over 80% of the macropores ranged 0.15-1 mm in diameter, and less than 20% of the macropores had a diameter greater than 1 mm. Ranging between 5.8%-22.7%, the macroporosity of granite residual soil first augmented and then reduced with the increase of soil depth. 2) Larger diameter of macropore resulted in a smaller round ratio. 3) The overall silhouette coefficient of four samples changed within 0.81-0.87, and such change attenuated with the increase of soil depth. 4) The macroporosity of granite residual soil is correlated with the fractal dimension; but the coefficients of such correlation of different samples varied distinctly. In summary, granite residual soil is of large porosity, small toughness, wide distribution of macropores, large difference in pore structure, and large dispersion of local pore flatness.

导出引用

阙云, 蔡沛辰, 李显. 花岗岩残积土大孔隙结构定量表征[J]. 长江科学院院报. 2022, 39(2): 82-88 https://doi.org/10.11988/ckyyb.20200987

QUE Yun, CAI Pei-chen, LI Xian. Quantitative Characterization of Macropore Structure of Granite Residual Soil[J]. Journal of Changjiang River Scientific Research Institute. 2022, 39(2): 82-88 https://doi.org/10.11988/ckyyb.20200987

中图分类号： TU43

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