The influence of humidity changes on the microstructure of loess
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摘要: 原状黄土具有显著的水敏性特征,为探究含水率变化对原状黄土微观结构的影响,通过多个含水率条件下原状黄土的扫描电镜试验,对黄土的微观特征进行定性分析;通过IPP6.0软件对SEM图像进行了二值化处理,对原状黄土的孔隙面积、孔隙直径、孔隙形态与孔隙角度分布规律进行了定量描述;利用皮尔森相关性分析方法对原状黄土含水率与微观结构指标进行了相关性分析。结果表明:含水率变化会显著影响黄土的颗粒形态与孔隙分布特征,表现为总孔隙面积、大孔隙面积、平均孔径、圆度和凸度随含水率的增大而增大,孔隙概率熵随含水率增大而减小。Abstract: Undisturbed loess has significant water sensitivity characteristics. To explore the influence of moisture content change on the microstructure of undisturbed loess, scanning electron microscopy tests of undisturbed loess under multiple moisture content conditions were carried out, and the microscopic characteristics of loess was qualitatively analyzed. The SEM images were binarized using IPP6.0 software to quantitatively describe the pore area, pore diameter, pore morphology, and pore angle distribution of undisturbed loess. The Pearson correlation analysis method was used to analyze the correlation between the moisture content and microstructure indicators of undisturbed loess. The results show that changes in moisture content significantly affect the particle morphology and pore distribution characteristics of loess, manifested as an increase in total pore area, large pore area, average pore size, roundness and convexity, and moisture content with increasing moisture content, while the probability entropy of pores decreases with increasing moisture content.
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Key words:
- undisturbed loess /
- humidity /
- microstructure /
- correlation analysis
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表 1 基本物性指标
密度ρ/
(g·cm−3)比重
Gs含水率
w/%液限
wL/%塑限
wP/%塑性指数
IP1.36 2.70 22.0 39 25 14 表 2 黄土孔隙概率熵
含水率w 5% 10% 15% 20% 25% 36% 孔隙概率熵值Hm 0.8464 0.8086 0.8564 0.8216 0.6690 0.6798 -
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