Abstract: The process of Atterberg Limit determination of Zhengzhou silty cohesive soils is first demonstrated in this paper. The existing data processing methods of analytical method and Excel spreadsheet method are briefly introduced and a new method that using the AutoCAD method for the graphical Atterberg Limit solutions is also presented. After the comparative study, following conclusions could be made: The analytical method requires establishing formulas in Excel spreadsheet and the initial process is relatively tedious. However, it can be repetitively used after the initial establishment; the AutoCAD graphical method is more straight forward more accurate and easier to understand, compared with the hand drawing method. However, this method has no repetitive and new graphics are need each time. The graphical method within the Excel spreadsheet is just between the above methods. The manual operation is still necessary for the intersect point established by the regression method. Based on the results of Atterberg Method obtained by the analysis method, except for the difference of 0.2% between the plastic limit and that obtained by the Excel graphical method, the remaining data and its error are within 0.1%. It is concluded that three data processing methods can meet the precision requirements.

Key words: atterberg limits, analytical method, excel spreadsheet, AutoCAD