抗疏力固化剂改性黄土进失水能力研究

抗疏力固化剂在我国黄土加固中运用较少，探究抗疏力固化剂是否有利于维持黄土内部干燥状态很有必要。采用抗疏力固化剂对重塑Q3黄土改性，室内开展水滴入渗试验、柔性壁渗透试验、收缩试验及压力膜仪脱水试验，分别探讨抗疏力固化剂掺量对黄土进水、渗透及失水能力的影响。结果显示，随抗疏力固化剂掺量提高，土样斥水性急剧增大，明显优于粉煤灰、水泥、石灰改性土；渗透系数基本不变，水的流通性基本不变；干缩失水过程改性土样含水率及土-水特征曲线毛细作用区曲线斜率均变化不大，黄土失水能力基本不变。结合电镜及压汞试验结果可知，抗疏力固化剂对黄土中大孔隙、中孔隙体积含量影响较小，从而对黄土中水的流通及失去能力影响较少，证明抗疏力固化剂改性黄土斥水性明显提高，而失水能力基本不变，有利于维持黄土内部的干燥状态。

Water entrance-and-release ability of loess soil modified by consolid system

To extend the application of consolid system in loess soil improvement in China, this paper intend to verify that consolid system helps maintain a dry interior condition of loess soil. consolid system was mixed into remolded Q3 loess soil for laboratory tests including water drop penetration time test, flexible-wall permeability test, drying shrinkage test and soil-water characteristic curves(SWCCs) test, to investigate the water entrance ability, water permeability, and the dewatering ability of loess soil to different consolid system content. Test results show that, with the increasing proportion of consolid system in the modified soils, water repellency ability of the soils is sharply increased, much better than the soils modified with flyash, cement or lime. Permeability of modified loess soil is almost the same as the un-solidified loess soil, indicating that water flow capacity remains unchanged. Both of the moisture content in drying process and the soil-water characteristic curves(SWCCs) on the capillary action area of modified soils have little changed, indicating that dewatering ability of modified loess soil remains almost the same. These observations are consistent with scanning electron microscope(SEM) test and mercury intrusion porosimetry (MIP) test results, that consolid system has little influence on volume content of big and middle pores. It is concluded that consolid system is benefit to maintain a dry interior condition in loess soil because it sharply increases the soil water repellency ability but has little variation on the original permeability and dewatering ability of the loess soil.