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Analysis of fatal injuries by collapses in the past decade (1991 and 2001.) Served to confirm that he was an average year 63 cases and was more than 20% of fatal injuries in the sector. Approximately 65 – 66% injuries accounted for stope (lava). On the face of development workings and for the duration of preparatory workings account for 22 – 23% and 12 – 15%. The latter occur mainly in perekreplenii. Of the total number of accidents occurring in the lavas, about 30% are so-called terminal sites (niches, conjugation). They include the width of the ventilation, conveyor (haulage) drifts (well built) and approximately ten - length lavas. Cause of the collapse are significantly different. On interface development workings (conveyor, haulage) with stope pillar in the application development systems breed often cave as a result of significant exposures of the roof because of the removal of the window a large number of feet of lava lining, delays and poor recovery, The presence of broken rock bolting over the workings etc. On the conjugation of ventilation development workings with the lavas of particular importance in many cases become so-called time factor. Fundamentally different is the stress-strain state of the coal and surrounding rocks in the vicinity of its niche adjacent to the array of coal in the application of continuous development systems.
It is obvious, and concluded that the difference between the direct causes of injury from the cave necessarily requires the use of various ways to prevent collapse. This conclusion is completely true, and to develop ways to prevent injuries directly in lavas. The most radical and technological solutions to prevent injuries in the lavas, of course, is the application of the specific mining-geological conditions of the complexes (by). Security, technology, volume of work involved in the terminal areas of lava, carrying out and maintaining the development workings, of course, depends on the methods used to protect the workings and on the means, methods of attachment. Widely used in the present frame lining approaching lavas deformed, as a rule, very unevenly, lose stability, is costly to perform dangerous work to repair the workings.
Quite convincingly, in our opinion, has previously been shown that in such circumstances should not assume the tension weight of overlying rocks and resort to the use (application) of highly scientific terms such as stress – strain state, the zones of high rock pressure, stress concentration, etc. etc. everything is quite simple and clear, if carefully considered, to study, to understand the natural, natural essence of rock pressure. It is not consistent with the concept, well established and accepted by the experts – analysts in the past no less than 50 years. But it simultaneously and in contrast to the classical analytical solutions fully confirmed by numerous cases of specific practices. For many years in many countries around the world, including in Ukraine were conducted research aimed at preserving the stability of excavations, to prevent injury due to injection in the rock mass, capable of holding mining, fastening resins (solutions). Called a variety of mining science was not directly relevant to the topic of the monograph, so the question is, of course, do not consider in detail. However, at the same time must express understanding of the practical usefulness of these decisions, and willingness to use the recommendations UkrNII that became normative in Ukraine, if they meet the requirements (conditions) of the specific geological and mining – technological conditions. The most significant element of novelty of the proposed solutions to be used, is that the recommendations do not contain UkrNII regulate the use of hardening time, Patent DonNTU [5] classified application of the method is not the time for the direct workings where an array of virtually impermeableAnd the time has passed, 150 - 180 a day. After the excavation, when ugolnoporodny array stratified and may well be strengthened, «glue» at the expense of filing solutions, such as epoxy resins in the plane bundles. It is possible to use any schemes drilling blast holes through which can be injected into an array fixing liquid (solutions). Names are used approach to solving the problem of maintaining stability workings almost exclusively refers to the end sections of lavas adjacent to the developed space or previously held a preparatory workings.
For many years (not less than fifty – sixty) is traditionally in the USSR, including Ukraine, and in all other coal – producing countries of the world issues of sustainability (ohrany0 development workings are resolved from the standpoint of the ability of host rocks, these elaborate, resist rock pressure. At the same time under it (rock pressure) means the gravitational tension coal containing the array, due to the overlying stratum. For special conditions not excluded tectonic stresses. Schematic diagram of the solution of problems, both theoretical and application-oriented, was that production was seen, around which as a result of its holding in a tight array formed (there) of varying intensity. Stability of the formulation was determined by the ratio of tension and strength, deformation (including rheological) properties of rocks containing formulation. Given these factors, design issues were solved and lining materials for them. While this approach was in keeping with the provisions of the classical continuum mechanics, the nature (cause) many cases of destruction of mines, he has not been satisfactorily explained. In particular, it referred to the change (improve) the stability of single development workings after perekrepleniya [1] et al. From classic rock mechanics positions such results almost inexplicable, since the physical – mechanical properties of rocks; form of working, the type and concentration of stress, the depth of design that causes the initial tension coal containing the array remain unchanged. Based on those scientific statements that characterize the emergence and development of DHA during unloading, offered the following effect (change) direction of strain as they approach and removal of sewage treatment works to a particular section of the haulage drift. It was supposed that the existence of compensatory trench (1) the depth h = 1,2 m, which was formed by drilling and blasting method simultaneously with the haulage roadway, reduce the amount of strain shale from its foot in the direction of production.
Compensatory Education niches depth l = 0,7 m, held every 3 m hammer as of advance of roadway, was intended to reduce the strain of the same shale in the direction of the same generation, but by her foot and the wall (Fig. 6.15). The method used when developing inventory reservoir Stepmother gor.360m before reaching the boundary of the mine field for 205 m haulage roadway. The entire length of production is not perekreplyalas never. Previously presented results of direct measurements of DHA 1 and II of the strike allowed to argue that the distinction between them can be about the order. So that with the greatest practical utility of using these features of the deformation of layered media – array of sedimentary, that are essential to change contained in Figure 6.15, the orientation of compensatory niches and trenches. This decision is contained in the patent DonNTU described in [5]. It implements a scientifically based requirements for such a compensation arrangement cavity, where the greatest strain perpendicular to the bedding planes, as much as possible would be forwarded to the compensation (unloading) of the cavity (ris.6.16). Broken ground of the last harvest can only acceptable minimum levels. As part of their remaining unfilled, should be placed fast – foam
