在建筑工程勘测设计中,常以流限、塑限和土的天然含水量来计算土的稠度,评价粘性上的坚实程度。在确定天然地基容许承载力大小时,流限、塑限指标是重要依据之一。在交通、一水利工程的填土压实巾,流限、塑限指标可以问接判断土的压实程度,估计土的最优含水量和最大干么重。因此,流限、塑限试验是土的物理性试验的厦要项目之一。但是,要完成一个土试料的流限、塑限试验,费工费时较多。尤其是塑限试验,要用手工搓条法,搓条标准不易掌握,试验工效低,成果误差较大。为了改进流限、塑限试验技术,国内外一些研究单位做了大量的工作,提出了压力法、压扁法、瓦氏圆锥仪联合测定法等不同的改进方 In the construction engineering survey and design, often with flow limit, plastic limit and the natural soil moisture content to calculate the soil consistency, evaluation of the viscosity of the firm. In determining the natural foundation allowable bearing capacity, the flow limit, plastic limit indicator is one of the important basis. In traffic, a water project filling soil compaction towel, flow limit, plastic limit indicators can be asked to judge the degree of compaction of soil, soil to estimate the optimal water content and the maximum dry weight. Therefore, the flow limit, plastic limit test is a physical test of the soil to one of the buildings to be. However, to complete a soil sample flow limit, plastic limit test, more time and labor costs. In particular, the plastic limit test, the manual rubbing method, rubbing the standard is not easy to grasp, test work efficiency is low, the results of larger errors. In order to improve the flow limit, plastic limit test technology, a number of research units at home and abroad have done a lot of work, put forward the pressure method, the flattening method, Valsalva conic instrument combined determination of different improvements