Abstract
Problem Statement (Relevance): This article looks at the method of engineering stable pit slopes based on the three-dimensionally stressed state of rock and aimed at the prevention of accidents and emergencies at mining sites. Mining industry is characterized by a great number of hazardous factors posing threat to the lives and health of mining personnel. Such hazardous factors, which turn mining operations into a highly complicated work process, include a great number of machinery concentrated in the working area, as well as the risk of being exposed to hazardous gases, fires and rockslides. Rockslides constitute every fourth accident that happens in mining. The biggest hazard with underground mines includes the areas where collapses can occur due to incorrect mining operation parameters selected, whereas in open pits it is slopes and walls that can cause landslides and collapses. The causes of landslides in open pit mining include poorly designed pit slopes and waste dumps; failure to comply with the design parameters; violation of the process parameters. Objectives: The objective is to improve the emergency prevention system at the design stage with the ultimate goal of reducing the number of collapses and landslides at mining sites. Originality: The existing engineering methods of VNIMI, which are extensively used in the design of open-pit and combined mining processes, tend to overlook the stress-strain state of the rock mass and therefore cannot be relied on when selecting the slope reclamation parameters. Stability calculations are carried out based on a straight line or a circular cylindrical line of slide. However, as the practice shows, due to strain the pit slopes have a spherical shape. Findings: The proposed method for calculating the three-dimentional slope stability safety factor is based on adding together the holding and shear forces while allowing for the varying force direction on a spherical slide surface. Practical Relevance: The mining emergency prevention system improved at the design stage may reduce the number of collapses and landslides at mining sites. The authors also analysed the existing methods used to calculate the pit slope stability.
Keywords
Accident, emergency, open pit, landslide, stability factor, slide surface.
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