水盐含量对寒旱区黄土状盐渍土强度特性和渗透特性的影响

为探究含盐量和含水率对黄土状盐渍土力学特性的影响,本文通过人工配制不同含盐量的黄土状盐渍土进行室内三轴试验,分析了不同含盐量和含水率条件下的黄土状盐渍土抗剪强度参数和渗透系数的变化规律。结果表明：低含水率时,盐渍土的抗剪强度参数随含盐量的增大呈现出先增大后减小的趋势,在无水硫酸钠掺量为3.2%时,抗剪强度指标达到最低；高含水率下,盐渍土的抗剪强度参数随着含盐量的增大而减小；在含盐量一定的条件下,盐渍土的抗剪强度参数均随含水率的增大而减小,且含盐量越高,抗剪强度指标随含水率的变化越明显。另外,含盐量一定时,随着含水率的增大,盐渍土的渗透系数呈现明显增大趋势；在含水率一定的条件下,盐渍土的渗透系数随含盐量的增大而减小,且含水率越高,渗透系数随含盐量的变化越大。

Effect of moisture and salt content on strength and permeability characteristics of loess saline soilin cold and arid regions

In order to investigate the effect of salt content and moisture content on the mechanical properties of loess-like saline soils, indoor triaxial tests were conducted by manually preparing loess-like saline soils with different salt contents, and the variation of shear strength parameters and permeability coefficients of loess-like saline soils under different salt content and moisture content conditions were analyzed in this paper. The results show that the shear strength parameters of saline soils show a trend of increasing and then decreasing with increasing salt content at low moisture content, and the lowest shear strength index is reached at 3.2% of anhydrous sodium sulphate; shear strength parameters of saline soils at high moisture content decreasing with increasing salt content; Under certain conditions of salt content, the shear strength parameters of saline soils all decrease with increasing water content, and the higher the salt content, the more obvious the change of shear strength index with water content. In addition, at a certain salt content, the permeability coefficient of saline soils shows a clear tendency to increase as the water content increases; at a certain water content, the permeability coefficient of saline soils decreases with increasing salt content, and the higher the water content, the greater the change in permeability coefficient with salt content.