Experimental study on consolidation and hydraulic behaviors of Victorian brown coal

The Victorian brown coal is usually considered as a kind of intermediate geotechnical material (IGM), which has the properties between traditional rocks and soft soils. The brown coal is rich in organic matters and has complex textures and physical composition. It has different basic geotechnical index values from soft clays including low density and specific gravity, high water content, large void ratio and a relatively low hydraulic conductivity. The consolidation tests are carried out using the undisturbed brown coal samples, and the test results show special deformation behaviors of the brown coal. There is an instantaneous settlement at the early stage of the consolidation process, and the immediate settlement contributes to more than 50% of the total settlement occurring in the first several minutes. The Casagrande graphic method is not applicable to the brown coal to determine parameter t₉₀ and other parameters. Even the traditional Terzaghi’s consolidation theory can not describe the consolidation curves appropriately. The constant head tests are designed and carried out under relatively low confining pressures. The test results show that the brown coal has a relatively low hydraulic conductivity.