Abstract: This paper introduces an accurate method of calculating the soil replacement ratio (m value) of both single and double row grid distributed columns of composite ground in the soil improvement projects. The m value can also be obtained in CADD. The results indicate that the accuracy of m value is governed by the selection of the representative composite soil elements and the section area of the columns (As). Through the CADD commands of "Boundary" and "Area", the column section area can be easily calculated.

Key words: Composite Ground, Column-Soil Replacement Ratio, Column-Soil Element