Vol 99

The use of heat flows to destroy rocks has found wide application in various technological processes of mining production (drilling, reaming, cleaning of workings from the frozen mass, sinking, etc.).

One of the ways of preparing frozen rocks for excavation is thawing. However, the use of traditional heating methods for this purpose can not be recognized as satisfactory, both because of the low rate of thawing due to the low thermal conductivity of frozen rocks, and because of the negative effect of heating sources on the thermal regime of excavation.

In the open mining method of deposits represented by strong rocky rocks, the greatest costs of labor and funds (80-90%) come to the processes of destruction of the massif and crushing of rock mass.

When using electromagnetic fields of the microwave range for thawing frozen rocks, the following problem arises.

In the stone processing industry at destruction of strong rocks connected with surface treatment of blocks, board stone and other products, gas-air thermal breakers are widely used, the work of which is accompanied by emission of noise of high intensity into the environment.

The study of the possibility of using electromagnetic fields of HF and UHF range for intensification of the development of frozen rocks of alluvial deposits requires, first of all, the determination of complex dielectric permeability, which allows us to assess the ability of frozen rocks to absorb electromagnetic energy of different frequencies, quantitatively describe the processes of their heating by electromagnetic fields, creates a basis for the selection and calculation of parameters of electrothermal devices.

The energy of the shock wave of HC in rocky rocks is much greater than the energy of the shock wave in water. In a number of rocky rocks it is 80% or more of the potential energy of the charge.

A large number of studies have been devoted to the investigation of various aspects of the process of deformation and destruction of rocks during underground explosions...

In modern technology of explosive stripping at carrying out of mining excavations the more and more application are parallel cuttings, the principle of work of which consists that at explosion of borehole charges there is destruction of a rock cofferdam between the charged boreholes and an idle borehole, as a result of what is formed a cuttings cylindrical cavity of the greater depth.

Large mass explosions and intensification of rock stripping at active quarries, located near buildings and engineering structures, make it necessary to predict the action of shock air waves (SAW), as they can, represent a certain danger.

Around the cavity formed in the rock mass, under conditions of high rock pressure, there is a redistribution of the static stress field. Near the contour of the cavity there are three zones: stratification (squeezing), unloading and support pressure.

The equation of state of rocks allows us to obtain closed systems for the theoretical solution of many problems. However, to date, this problem is little studied, most often the simplest models are considered, such as incompressible fluid (equation of state p = const) or elastic body (Hooke's law).

The process of lump formation during rock destruction by impact or explosion in lump size statistics is studied from the point of view of the possibility of describing the distribution of random lumps by a suitable analytical expression.

The use of directional explosive charges for contour blasting and preliminary slotting in rock masses has attracted the attention of many researchers in recent years.

In association Glavlenstroymaterialy three granite quarries on extraction of a piece stone are operated: Perkon-Lampi of POGK Kuznechnoe, Vozrozhdenie of Vyborgsky Quarry Directorate and Kamenogorsky quarry.

The peculiarity of solving the problem of optimality of rock crushing by explosion at crushed stone quarries is that simultaneously with the analysis of the quarry equipment, whose productivity depends on the output of large fractions of crushed material > 200 mm, it is necessary to consider the issue of reduction of small fractions of substandard material size < 3 mm.

To conduct the most labor-intensive mining work in the construction of excavations, trenches, site planning is the most widely used drilling and blasting method. However, the use of blasting is often hampered by cramped conditions, when in the immediate vicinity are buildings, structures and other objects.

The Vivikond open pit mine uses a non-transportation system of mining. Overburden rocks - peat, sands, loams and clays with an average thickness of 5 m and limestone with an average thickness of 8 m are moved by excavators ESH-10/60, ESH-15/90 and excavator EKG-4,6 into the excavated space at a distance of 40 m.

Each aluminum particle is covered with a dense and strong oxide film, which is inert and prevents the metal from reacting.

Modern cone drilling machines for drilling wells from the surface are capable of drilling vertical or inclined wells up to 320 mm in diameter and up to 30 m deep. In the underground development of deposits are used wells drilled at any angle to the horizon, and machines for their drilling provide penetration of wells with a diameter of up to 105 mm and a length of no more than 100 m.

The process of teeth penetration into the rock with sliding consists of two processes: penetration and sliding. Destruction of rock when bit teeth are embedded in it is sufficiently studied in a number of works.

Процесс внедрения зубьев в породу со скольжением состоит из двух про­цессов: внедрения и скольжения. Разрушение породы при внедрении в нее зубьев долот достаточно изучено в ряде работ ...

One of the urgent problems affecting the efficiency of mining production is the preparation of rock mass for loading. This problem includes not only works on crushing of rocks by mass blasting, but also destruction of oversized pieces.

At the system of underground development of mica-bearing veins of small and medium thickness with open cleaning space, which is being implemented nowadays, it is necessary to drill vertical or slightly inclined boreholes with a diameter of 50-75 mm and a depth of 15-25 m.