Justification of the Optimal Granulometric Composition of Crushed Rocks for Open-Pit Mine Road Surfacing

Abstract

Abstract. The specific weight of the open coal mining method in Kuzbass is constantly growing due to higher hazard and low profitability of the underground mining method. It is possible to reduce the cost of open-pit coal mining using overburden rock in constructing temporary pit roads. The purpose of the work is to justify the possibility of using overburden rock for the construction of temporary technological roads. To this end, we set the tasks to determine the rational granulometric composition of crushed rock, dependences of its unit weight, static elastic modulus, and ultimate shear resistance. This study justifies the most efficient granulometric composition of crushed rock based on theoretical studies of the optimal structure of granular materials, taking into account the probability theory of particle-particle packing, laboratory studies of the dependence of the unit weight and the static elastic modulus on the content of particles of different sizes, and also the calculation of ultimate shear resistance of crushed rocks. As a result of the conducted studies, it has been established that the optimal granulometric composition of crushed rock, which at the same time ensures high values of unit weight, static elastic modulus and ultimate shear resistance, is achieved when the content of particles larger than half of the maximum is 40 to 55% and increases integrally with decreasing of the average particle diameter.

Automated Forecasting of the Particle Size Composition of Blasted Rocks During Blasthole Drilling in Horizontal Underground Workings

“…In works (Hekmat, 2018;Faramarzi et al, 2013: 82-94;Shalamanov et al, 2017;Campbell, 2017) focus on the assessment of the quality of the blasted rock mass typically apply the widely known Kuz-Ram model of distribution of the particle size composition of rock cuts named after its authors Kuznetsova and Rosin-Rammler. They are designed to assess the the particle size composition of rocks after the explosion and do not provide a forecast of the quality of crushing before the explosion.…”