氯化钠溶液对膨胀土膨胀特性的影响

Effect of Sodium Chloride Concentration on Swelling of Expansive Soil

对一种膨胀土进行一系列氯化钠溶液浸水饱和加载膨胀试验,在不同垂直压力下,探究膨胀土被不同浓度氯化钠溶液饱和的膨胀特性。结果表明,在相同垂直压力下,试样的饱和孔隙比随着氯化钠溶液浓度的增加而减小。主要因为氯化钠溶液增加,降低了膨胀土的膨胀力,导致饱和孔隙比减小。以蒸馏水饱和的试样为基准,采用等量替代的方法得到不同浓度下产生的相对化学力,相对化学力随着浓度增加而增加,随着孔隙比增大而降低。最后给出相对化学力与溶液浓度和孔隙比的关系。

A series of loading-swelling tests were carried out for an expansive soil saturated with sodium chloride solution.Under different vertical pressures,the swelling characteristics of expansive soil saturated in different concentrations of sodium chloride solution were investigated.The results show that under the same vertical pressure,the saturated void ratio decreased with the increase of NaCl solution concentration.The main reason is that with the increase of sodium chloride solution,the swelling force of expansive soil decreased,resulting in the decrease of saturated void ratio.Based on the sample saturated with distilled water,the relative chemical force at different concentrations was obtained by equal substitution method.The relative chemical force increased with the increase of concentration and decreased with the increase of pore ratio.Finally,the relationship of relative chemical force to solution concentration and pore ratio was given.