两种测定塑限的试验方法比较——基于福建省典型残积土

The Comparison of Two Test Methods for Plastic Limits——Based on Typical Residual Soils from FUJIAN Province

基于测定塑限的土工试验方法,以福建省典型的3种残积土为研究对象,用滚搓法和液塑限联合测定法对残积土的塑限试验进行对比分析。结果表明,滚搓法受人为因素影响较大,对操作人员的要求较高,不同操作者的试验结果变异系数较高,但对设备的要求低,同时也有一定的准确度,是一个有代表性的普适方法;液塑限联合测定法可以最大程度消除操作人员对结果的影响,试验结果变异系数低,但需要仪器管理人员有较高的专业素养,以保持设备的高效准确运行。在复杂的工程实践中,建议两种方法共同实施,尽可能准确地反映残积土的真实物理性能。

The test methods for plastic limit of soil were introduced in this paper. The typical residual soils from FUJIAN province were investigated with thread - rolling method and liquid - plastic limit combined method. Analyses were carried out between the two methods. The results indicate that thread - roiling method is easily affected by the operators. The variable coefficient of same samples is higher with different operators. But it is a typically moderate accurate method with simple equipment. The liquid - plastic limit combined method works more accurate than thread - rolling method as the excluding of the manual errors. The variable coefficient of same sample is much lower. However, the professional maintenance should be implemented periodically to keep the equipment efficient and accurate. Both methods are suggested to be carried out in some complex projects in order to demonstrate the real physical properties of the residual soils.