Abstract: In order to explore the restriction characteristics of mineralization degree on capillary water rising height under different soil types, three kinds of sandy soil and sandy loam were selected to carry out soil capillary water test under the influence of mineralization degree by indoor column test, the difference of capillary water rising height under the influence of particle size and mineralization degree was quantitatively characterized, and the logarithmic function fitting model was proposed. The experimental results show that total dissolved solids (TDS) restricts the rising height of capillary water by changing the gravity potential and matrix potential of soil water. When TDS was 0.8, 15.0, and 50.0 g/L, after 72 hours, the maximum capillary water rising height ( $ h_{max} $) of medium sand was 32.5, 31.3, and 30.2 cm, the $ h_{max} $ of fine sand was 50.4, 48.6, and 48.7 cm, the $ h_{max} $ of silt was 72.3, 76.4, and 76.0 cm, and the $ h_{max} $ of sandy loam was 59.0, 60.2, and 58.6 cm. In terms of capillary water rising rate, the rate change of silt and sandy loam fluctuates greatly, and the relationship between capillary water rising height (h) and time (t) in the whole test cycle can be described by a three-parameter logarithmic function. The results of this study reveal the restriction characteristics of TDS on capillary water rising height, further deepen the research on the rising height of capillary water, which can provide technical support for the treatment of soil salinization and the formulation of groundwater ecological water level.
Keywords: capillary water rising height; total dissolved solids(TDS); column test; gravity potential; matrix potential
合肥工业大学学报自科版