WANG Dong-wei, LU Wu-ping, TANG Chao-sheng, et al. Sample preparation technique and microstructure quantification
method for sandy soil[J]. 2019, 40(12): 4783-4792.
DOI:
WANG Dong-wei, LU Wu-ping, TANG Chao-sheng, et al. Sample preparation technique and microstructure quantification
method for sandy soil[J]. 2019, 40(12): 4783-4792.DOI: 10.16285/j.rsm.2018.1857.
Sample preparation technique and microstructure quantification
method for sandy soil
The microstructure of soil is an important internal factor that determines its engineering properties. However
preparing suitable samples for microstructure analysis and quantifying structural parameters have always been challenging. A method of vacuum freeze drying-glue injection for preparing sandy soil samples is introduced. This method can remove water and maintain the samples’ original structure for further processing. A series of sample images with different grain sizes were taken by SEM and optical microscope
respectively. Based on the self-developed soil microstructure quantitative analysis system SMAS
the images were quantitatively analyzed. A quantitative index system composed of soil particle number
particle perimeter
apparent porosity
shape factor
equivalent diameter
fractal dimension and shape ratio were proposed and used to quantitatively evaluate the microstructure characteristics of sand soil samples. The results show that the vacuum freeze drying-glue injection method for preparing samples has the advantages of convenient operation and reliable results
which can effectively maintain original structured sand. In comparison
SEM is more suitable for the microstructure analysis of fine sand
while optical microscopy is more suitable for medium/coarse sand. SMAS can effectively identify soil particles and pores in microstructure images
providing an efficient tool for quantitative analysis of the microstructure characteristics of sand or other soils.