Using analysis method to calculate the data measured by liquid-plastic limit combine experiment can determine liquid limit and plastic limit.

The causes of the abnormal phenomenon for the liquid-plastic limit are analyzed with regard to the pseudoplastic phenomena,the test process of liquid limit and the plastic limit water content,the grain-size distribution,the compositions of mineral and the ion exchange,and accordingly,the naming method of silt is further discussed.

In view of so many problems caused by traffic standard which using drawing graph to define the liquid and plastic limit,the paper based on the data tested by Minimum Quadratic Multiplication to calculate liquid limit and plastic one,they are drawn up the QBASIC programme which processed by a computer.

The liquid limit and plastic limit test is a conventional geotechnical experiment.

Calculating method of moisture content limitationfor combined measure method of liquid and plastic limits;

In view of the inconvenience of diagrammatic method adopted for determining the liquid and plastic limits stipulated in the experimental regulations for highway,hydropower,and geotechnical engineering,we present the analytic method,least square method and regression analysis method in the form of QBASIC programme processed by computers.