Edinburgh Napier University

  The four grading entropy coordinates can be used for soil classification on the basis of grain size and the grading curve shape (similarly e.g., to the diameter values). The grading entropy coordinates give information on several basic Physics features of soil like minimum dry density, internal structure and degree of degradation for natural soils. Therefore, assumingly, using them, good permeability k regression relations can be elaborated. In this work some laboratory tests are made for saturated permeability on fractally distributed sand mixtures (which are mean grading curves with predetermined composition). After the first stage of the measurement it is found that, the results indicate that the preciseness is better if only the data of non-segregating, internally stable mixtures are used, indicating the importance of selecting non-segregating mixtures in laboratory tests.