Study on the surface particle distribution characteristics of silt with different moisture content

Abstract

Soil structure and particle distribution determine the action form of water and the distribution and movement form of water in the soil, which may cause many engineering and environmental problems, so it is of great significance to study the distribution form of soil particles under different moisture content. Taking the silt as the research object, the surface micro features of soil samples with the same dry density and different moisture content were collected, and the binarization analysis and particle statistics were carried out to study the action mode between water and particles. The results show that (1) moisture content has a certain impact on the micro features. With the increase of moisture content, the pores between soil particles gradually decrease, and the fractal dimension of surface particles also decreases. (2) In the case of the difference of specific surface area, the smaller the particle size, the more obvious the response to water. For this silt sample, the particles with a size of 0.03~0.05 mm are relatively stable. With the increase of moisture content, small particles flocculate to form large particles under a series of forces. (3) When the moisture content was 8.92% and 13.78%, the soil features changed significantly, which may be the critical moisture contents affecting the structural quality of the sample. (4) Advantage orientation of silt particles is 90°~105°, which may cause the soil mechanics characteristics of anisotropy. (5) The interaction model between water and soil particles is as follows: dissolution, the change of stress on particles, and the change of electrical double layer on the surface of soil particles.