劣化对水泥土渗透性影响室内试验研究

Laboratory tests on effect of deterioration on permeability of cement soil

为研究水泥土渗透性随劣化程度的演化规律,通过模拟水泥土在腐蚀场地的形成过程制备完全劣化水泥土试样,并实施了一系列的室内渗透试验。试验结果表明:浸泡溶液对完全劣化水泥土渗透系数的影响可忽略不计,可利用腐蚀性较强的溶液浸泡以加快完全劣化,缩短完全劣化水泥土制样时间。但是溶液浓度过高,可造成水泥土试样表面脱落,影响试样制备的质量;完全劣化水泥土的渗透系数与水泥掺入比有关,随水泥掺入比的增大,完全劣化水泥土的渗透系数呈减小的趋势;本文试验条件下,粉土水泥土完全劣化后的渗透系数与粉土的渗透系数接近,高岭土水泥土完全劣化后的渗透系数小于高岭土的渗透系数;水泥土完全劣化后的渗透系数远大于未劣化水泥土的渗透系数。研究结果可为腐蚀场地的水泥土止水帷幕设计提供理论依据。

The completely deteriorated cement soil samples were prepared by simulating the formation process of cement soil in the corrosive site,and a series of indoor permeability tests are conducted in order to study the evolution laws of permeability of cement soil with deterioration degree.The results show that the effect of soaking solution on the permeability coefficient of completely deteriorated cement soil is negligible,and it can be immersed by the corrosive solution to accelerate the complete deterioration and shorten the sample preparation time of completely deteriorated cement soil.However,the concentration of solution is too high,the surface of cement soil sample may fall off,which affects the quality of sample preparation.The permeability coefficient of completely deteriorated cement soil is related to the cement ratio,which decreases with the increase of cement ratio.Under the experimental conditions,the permeability coefficient of completely deteriorated silt cement soil is completely close to that of silt,and the permeability coefficient of completely deteriorated kaolin cement soil is less than that of kaolin.The permeability coefficient of completely deteriorated cement soil is much larger than that of cement soil.The research results can provide a theoretical basis for the design of cement soil waterproof in the corrosive site.