Consideration is given to the method of the geometric addition of forces over the most stressed slip surface in estimation of open-pit slope stability. The limits of its application are defined.
With permanent increasing of depth of open pit exploitation stress strain behavior of side array changes, so the choice of the necessary and corresponding to reality geomechanical scheme is an important issue. Currently,there is large number of software to estimation the stability slopes. This article provides a comparison of different programs based on numerical method and the method of limiting equilibrium.
Side deep pits are complex engineering structures, which depend on the state of mine safety. As bating and opening new horizons in the development of mineral deposits open as a result of long-term at the edge array of pits are changing the natural stress and accumulated fatigue, which leads to deformation of the sides, ending in some cases, catastrophic collapses and landslides. Prevention of dangerous destructive strains edge arrays depends on reliable assessment of emerging strains.
The Article considers the aspect concerning the prediction of one of indices of rock mass structure,i.e.a dimension of structural blocks of fractured stony and semistony rocks – the index which is required for transition from strength (cohesion) of rocks in a specimen to cohesion in rock mass in evaluation of open-pit slope stability. It is shown also the determination of reference value of the dimension of structural blocks by core from geological holes with the aid of RQD (Rock Quality Designation) at the stage of prospecting of one of ore deposits intended for open-pit mining.
New method of sandy - clay rocks high dump stability calculations is suggested. This method is fulfilled without errors. It may be applied to plastic rocks quarry slopes calculations.