【摘要】 在特定恒湿恒温条件下对两种土样进行吸湿含水率试验。一种是商用高岭土和美国怀俄明州班脱士(以蒙脱土为主),按班脱土含量分别为100％,50％,30％,20％,10％和O％的比例混合而成的土样,该混合土样可模拟不同膨胀等级的膨胀土;另一种采用中国广西3个盆地的膨胀土样。由试验结果可以看出,膨胀土的吸湿和脱湿平衡含水率有较大差别,但脱湿平衡含水率物理意义明确且稳定。将准吸湿含水率定义为60％脱湿法测定的平衡吸湿含水率。土壤最大吸湿含水率与膨胀土的蒙脱石含量、液限、塑性指数和自由膨胀率之间线性相关,能反映膨胀土的基本属性,因此是膨胀土鉴别和分类的重要信息。采用所提出的试验方法,设各简单,方法易行。对天然含水率的膨胀土试样进行试验,72h基本达到稳定,可以满足工程要求。更多还原

【Abstract】 Under the given condition of humidity of 60% and temperature of 25℃, two kinds of expansive soil are used for testing study on moisture content of standard absorption. One is mixed samples of kaolinite and montmorillonite in laboratory whose montmorillonite contents are 100%, 50%, 30%, 20%, 10% and 0, respectively, and another is expansive soil samples from three basins of Guangxi province, China. There is great difference between the moisture contents of standard absorption for soil from the tests of moisture absorption and dehydration. The physical definition of moisture content of standard absorption for soil from dehydration is clear and stable, so that 60% of moisture content of equilibrious absorption from dehydration is taken as the definition of moisture content of quasi-absorption. The moisture content of standard absorption for soil shows a linearity correlation with montmorillonite content, liquid limit, plasticity index and free expansive ratio of expansive soil, which reflects essential property of expansive soil, and is an important information to distinguish and classify expansive soils. The test method presented in this paper is simple and easy to run, so that the soil samples may basically arrive at stable state in 72 hours.更多还原