ISS减小红色黏土结合水膜的试验研究

Experimental study on reducing thickness of adsorbed water layer for red clay particles treated by ionic soil stabilizer

红色黏土结合水膜的厚度对其塑性、吸附性、渗透性、膨胀性和导电性等物理性质及强度、变形等力学性质起着控制性的作用。为了分析和计算离子土壤固化剂(ISS)处理红色黏土前后其结合水膜厚度的变化,进行了阿太堡试验、Zeta电位试验、电导率试验和比表面积试验。根据扁平状黏土颗粒结合水膜形成模型,推导了结合水膜厚度计算公式。根据液限含水率、比表面积和结合水密度,计算了ISS加固前后结合水膜厚度的变化。得出ISS加固红色黏土,能够降低其塑性指数,减小Zeta电位和电导率,从而使结合水膜厚度减薄,但不会改变黏土颗粒的双电层结构,不能完全去除红色黏土中的结合水。试验与理论计算结果表明,用塑性指数的降低来表征ISS减小红色黏土结合水膜是可行的、有效的。

The thickness of adsorbed water layer plays an important role in the plasticity,absorption,permeability,swelling,conductivity,strength,deformation and physical-mechanical properties of red clay particles.In order to analyze and calculate the thickness of adsorbed water of red clay before and after treatment with ionic soil stabilizer（ISS）,the Atterberg test,Zeta potential test,conductivity and specific surface area test are carried out.According to the model of flat clay particles,a formula for the thickness of red clay particles is deduced.In terms of liquid limit,specific surface area and density of adsorbed water,the thickness of adsorbed water is calculated.The results show that ISS can reduce the plasticity index of the red clay,Zeta potential and conductivity so as to decrease the thickness of adsorbed water,but the structure of electric double layer can not be changed and the adsorbed water can not be removed completely.The experimental and theoretical calculations show that the reduction of plasticity index to determine ISS reducing adsorbed water of red clay is feasible and effective.