Vegetation Limit and Erosion Limit of Artificial Soil

摘要

In this study non-erosive soil materials have been developed in order to realize a green slope in opencut mining. Practically, the vegetation limit and the erosion limit of artificial soil were determined on the basis of the vegetation tests of lawn grass and the erosion tests by water jet respectively.The specimens of soil were made of the tailings of cyanide leaching at the Kushikino gold mine through the following two processes (1) a mixture of the tailings, water, portland cement and woody fiber was crushed under 12 mesh after the primary generation of cohesive strength for a specific time, (2) the crushed products were applied to the tests of the secondary generation of cohesive strength after charging in a pot and consolidating under various compressive stress.From the results of the above tests it was proved that the cohesive strength R{#tau#, #rho#, #eta#}of the soil could coexist within the range between the vegetation limit V_c and the erosion limit E_c as given by the following inequality.R{#tau#, #rho#, #eta#}Here, the time #tau# of the primary generation of cohesive strength, the consolidating stress #rho# and the fiber content #eta# are the parameters of the soil strength. The measured values of V_c and E_c were 140 and 60 kg f/cm~2 respectively.