Struktura i geotechniczne właściwości wybranych gruntów antropogenicznych

Among the anthropogenic soils an distinguish group are dump soils originating mainly from both the open pit and underground mining operations. Dump soils are stored as a spoil banks of height up to 200 m and area up to several square kilometers. As gigantic earthen structures they must by designed and built accurately in order to assure their stability and safety of surrounding terrain. In order to attain this purpose geotechnical parameters of dump soil must be determined, particularly shear strength, compressibility and collapse settlement potential. In the following paper the results of studies on mentioned above parameters are presented and the relationships between structural type of dump soil, load, time and geotechnical parameters are discussed. Features of dump soils differ from those of natural soils. Their structure is initially loose and, in the case of cohesive dump soil, it consists of various-size lumps and pieces of clayey natural soils. Such soil reveal a double porosity including inter-lumps and intra-lump porosities. Loading and external factors such as rainfalls, weathering processes etc., cause permanent changes of this structure and, consequently, changes the geotechnical parameters of dump soil, as illustrated below by a set of diagrams.