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Faculty: Geotekhnologiy and management of operations
Speciality: Mineral Deposits Extraction
Traditional approaches to ensuring the sustainability of mine workings, based on increasing the metal roof at 1 linear meter (size specialtype increase, decrease step installation arched roof pliable, the use of roof strengthening, etc.) in a deep mine does not allow for steady condition of workings in the zone of influence of sewage cleansing works, but leads to a significant increase in the value of their holding. This is due to the inability to prevent the existing means of attachment formation and development of the area around the workings of areas destroyed rocks (ADR). On the relevance of the problem indicates that the current average unit mounting mine is about 16 m for every 1000 tons of coal, while restoration — 7.5 m for every 1000 tons [1], while the value set of arched roof is about 2000 UAH.
In our view, the violent opposition geomechanical natural processes occurring in the array has no prospects and can not lead to a state of long-term sustainable balance. The author develops technology for unrepaired workings of the state, based on its own strength of rocks and the prevailing ambient array sustainable state.
Because while maintaining elaborate, in a zone of influence of sewage treatment works, it is possible to identify two phases connected with the redistribution of stresses in the array - caused by the actual conduct of the formulation and maintenance of sewage treatment works, then you should choose the means of fastening for each of these stages, given the present state of the array at an earlier stage. The proposed approach is that in the first phase of the development of fixed traditional way, while the second - the role of roof is artificially created from the rock units within the ADR support structure. The formation of this construction is ensured by increasing the force of friction between the rock fragments within the ADR, which is achieved by means of their disposal. As a means of creating a proposed disposal of the application unexplosive destroying substances (UDS), could dramatically increase in the volume and create high pressure, which comes into home practice. Laboratory researches UDS properties [2] showed that these substances are able to provide the necessary pressure in the array.
Schematic diagram of the structure formation in the ADR, according to the proposed technology is shown in figure 1. In the figure, the following designations: B — the distance between the hole spacing of elements in the cross section generation, (m), a — hole depth (m).
But to justify the parameters of the proposed method of strengthening and developing technological passport is required to determine the influence of hole area with self material to determine the minimum spacing of the density per unit area strengthened in the development of workings. Therefore, the master's work relevant topic.
Aim of this work — justification of the parameters and definition of the scope of the proposed technology to strengthen the array in the area devastated by rock, based on self Materials
Idea work — is to create a stable bearing structure of the structural and nonhomogeneous rock mass by means of spacing elements on the basis of unexplosive destroying substances through their effect selfbroad.
1. Establishing patterns of transmission of pressure through the expansion of discrete material.
2. Defining the field of influence of element spacing.
3. Determination of the minimum required density of spacing components onunit area strengthened rocks.
Research object — structurally heterogeneous array of species.
The research — the processes of hardening of discrete arrays.
Methods of research — systematic, analytical method of physical modeling, the method of statistical treatment.
Scientific novelty is the following:
- first established pattern of pressure changes in the coefficient of transmission of the expansion in a discrete environment;
- The phenomenon of scattering and focusing of pressure around the spacing element are explored.
Practical value of the work is to develop technology designed to strengthen structurally controlled nonhomogeneous rock mass, to ensure a sustainable capacity him mine workings and reduce the cost of their maintenance.
Questions strengthening rocks surrounding mining is studied in detail [8]. Developed technological schemes and normative documents. However, the strengthening of existing technologies have several failings. The construction of a protective shell around the formulation by injection to strengthen [3] rocks associated with the need to use special equipment and expensive materials fastened. In addition, existing methods of injection formulations are not fastened ensuring that the local processing of rock mass in the required limits.
In recent years, in the world are beginning to be widely used unexplosive destroy material that could dramatically increase in the volume and create a high pressure as a result of the reactions of hydration.
Materials based on unexplosive destroying substances (UDS) is currently used in engineering construction for the destruction of the foundations and building structures. In coal woking, these substances are used for the destruction of strong brittle rocks, crushing blocks in the production of oversized rocks open, breaking stoning-semiprecious raw materials and other cases, instead of conventional explosives. This is due to the high safety performance, otsutstvuem seismic impact and explosive gases.
Author has the task of determining the applicability of UDS opposite purpose - to strengthen the formulation containing the mountain massif in the area devastated by rock, and to ensure its sustainability.
As technical means to create a disposition to be unexplosive use destructive means UDS-80, produced at the present time in Ukraine. This material is a powdery substance on the basis of calcium oxide, is a dusty, nonflammable, nonexplosive, which allows you to apply it in the mine environment.
Scientific research in this area in the world is not out.
Main prospect research is the use of the work in the coal industry of Ukraine.
Results of the master's work will serve as a basis for further research.
At present the work for the magister degree is being carried out, in January 2010. For farther information ask the author Ovchinnikov Sergey and teacher Sakhno Ivan