To meet the growing demand for earthworks of linear projects such as roads and railways, the Bruckner Diagram starts to become unviable, when more accurate surveys are made.
For example, in railroad design, surveys are performed on slopes and the platform in order to determine the CBR or ISC, liquidity limits, plasticizers, expanding, homogenizing factor, etc.
So, the materials are classified by its CBR and Expansion. In the proposed scenario above, the factor of homogenization may be different for materials from slopes of cuts or cuts in the subgrade.
The demands of materials within the project will also be required requirements. For example, in the design of the rail superstructure, define a ballast and subballast with fixed characteristics. As the subgrade may have desirable characteristics or not, is adopted strengthening the subgrade, which is calculated with enough height to deliver the subgrade allowable loads to the ground.
Thinking of these difficulties, the program DDM, comes as an option for solving this problem.