No abstract

Persistent intensification of mining in lacking of land for overburden storage necessitates maximizing intake capacity of the available dumps and involves dumping in difficult and deformation-prone conditions. A dump can start deforming at early stage of construction. The main cause of deformation is inconsistency of the dump design and the actual geotechnical conditions. Justification of slope stability of dump projects should rest upon site survey results. This article describes the lab-scale tests of rock refuse mixtures. The testing aimed to assess the influence of grain size and moisture content of samples on their shearing strength. The single-plane shear tests used GCTS RDS 200 system and ELE device for strong and loose rocks. The test data of rock refuse mixtures are compared with the dependences developed by Leps, which are commonly used abroad to determine strength properties of rock refuse in dumps. The analysis of the test results proves that the lab-scale single-plane shear testing of loose rocks allows taking into account special features of a project structure. On the other hand, the lab-scale shearing machines with a small shear area provide a wide scatter of data only suitable for an approximate analysis. Therefore, in construction of standard "simple" dumps, it is permissible to use curves analogous to Leps' relations, or the relations from this study.