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Roman Peshlyaev

Mountain Faculty

Mineral Deposits Development Chair

Speciality Mineral Deposits Development Chair

Increased operability arch compliant support

Scientific adviser: Ph.D., Professor Yuriy Petrenko

Resume
Abstract

Abstract

Content

• Introduction
• 1. Relevance of the topic
• 2. The purpose and objectives of the study
• 3. Summary of the scientific work
• Literature

Introduction

Rhythmic work of the coal industry of Ukraine, among other reasons, prevents unsatisfactory situation with the maintenance of mine workings. The length of the repaired workings amounts to 45-50 % of the length of the ongoing, and the level of an emergency condition - more than 15 % supported, reaching for individual mines and more than 25 %. Up to 40 % of the excavation is repaired before the commissioning. Constantly growing number of shop workers, exceeding the current 15 % of the underground group. The complexity of repair is about 80 human.-sm. 1,000 tons of daily production on average.

Perekrepleniya podryvki and are usually carried out when development does not meet the requirements for the state and must be stopped. All repairs are carried out practical manual and a high level of injury. The volume of rock from the repair of 30-60° of the issued amount on the surface of the rock.

About 90 % of fixed metal workings supple crepe, but its parameters are often taken insufficient substantiation ovano. Measures to preserve the stability of excavation required additional costs and not apply for economic reasons.

Taken in the last 30-40 years, attempts to improve the workings through the use of more powerful profiles and seals lining of positive results was not given. These activities have resulted in a to an increase in material and labor costs for maintenance.

Each year, the length of development workings, which are in poor condition, increased by 1-2 % (Table 1).

Table 1. Status of development workings in the mines of the Donetsk-
Makeyevka region of Donbass

1. Relevance of the topic

Master's thesis is devoted to studying the mechanism of yielding arched roof supports under the influence of oblique load and improve its efficiency. Research work involves solving problems associated with the stability of mine workings, the rational use of metal profile, cost to repair mine workings.

The urgency of the work lies in the fact that the predominant roof supports in the mines of the Donbass remains pliable metal arched roof supports, which recognizes about 90 % of mines (Table 2).

Table 2. The scope of application and the state of mine support

* - the amount of support,  %; 2 – deformed support,  %

2. The purpose and objectives of the study

The purpose of: choice of direction to improve the performance arched supple support.

Methodology and methods of study:equivalent modeling, engineering analysis and comparison.

The main objectives of the study:

1. Study mode yielding arched roof supports under the influence of the forces at different angles of its applications.
2. Study mode yielding arched supports in various conditions of use.
3. The use of different measures to improve the quality of yielding arched roof supports.

3. Summary of research

Experience in operating mines, enshrined arch support, shows [1] that the main factor that reduces the stability of the excavation is discrepancy between the direction of compliance with the permanent lining predominant rock displacements of the contour, which was noted in 59 % of surveyed workings.

In the mines, passed along strike, is dominated by the displacement of the contour in the direction normal to the bedding, ie large deformations are observed in the cross section of the roof from falling rocks, and soil - the part of the uprising. As in the reservoir, and in the field drifts Castle compliance is triggered, usually by falling rocks, and by the revolt and stand losing verhnyak alignment, compliance is not realized, the cut razvaltsovyvaetsya rack and clamps are broken.

Described the nature of lining deformations and uneven development of the width of the observed swelling of the soil in the survey of the 8th Field drift west of the mountains. 840m of mine "Novodruzheskaya" (Fig. 1a) and the 7th west of the field of ventilation drift layer m₃^нhorizon 650m mine them. GG Kapustin (Fig. 1b) and the other drifts conducted in layered rocks. When the angle of incidence of rocks 10-150 more dominant effect of the direction of displacement on the stability of the system, "crepe-array" appears in almost all cases, at lower angles, simultaneous operation of units compliance and maintaining a symmetrical development of high-quality fill, provided the fixing space, which, however, the practice of mounting openings are rare.

а

б

Pic 1. The manifestation of the uneven displacement of rocks along the contour of the workings:
a – in the 8th field drift west of the horizont 840m of mine "Novodruzheskaya"
b – in the 7th West Field airway reservoir m₃^н horizont 650m mine
name G.G. Kapustin

In the mines passed across the strike and down dip and rock rebellion (only 12 % surveyed) the prevailing bias circuit different from the direction of compliance, manifested in location of the longitudinal axis of the openings in the range of angles to the line of strike of 30-60° species. Thus, to evaluate the efficiency arch support, depending on the direction of the largest displacements were conducted laboratory studies. For research was designed and built a special stand (pic. 2).

Pic. 2. Stand the test of efficiency arch support

The design of the stand next. In the frame of a spatial model of agriculture established (three-tier) from the AEP-27 - 2 on a scale of 1:20. Load on the supports created with the help of a lever 3. simulated angles oad application 0, 5, 10, 15, 20, 25 and 300, which changed the location of the mount lever 3 to the space frame. Moving load-bearing elements in the castles lining measured by calibrated scale marked on the load-bearing elements in the vicinity of the locks. The results of measurements in relative units are presented in (Table 3).

Table 3. The results of measurements

As can be seen from these data, even at an angle of incidence 10° is observed uneven deformation nodes compliance. Thus at an angle of incidence of rocks 15° (the most a typical angle for the conditions of the Donets Basin) yielding the node number 2 is reduced by 20 %, and at an angle of 30 ° - 80 %. After that, the frame goes into the hard mode, virtually using their potential. Thus, studies have shown that improving efficiency arch support is necessary to change the location of nodes compliance, taking into account the angle of deposition of rocks ..

pic. 3. Stand the test of efficiency arch support.

For this purpose, was formulated and solved the following problem.

It is known that the elements trehzvenevoy arch support combined with the flexibility of locks. Acting in the cross sections of the frame internal forces due to external loading, provide work interlocks. Then it is logical to assume that frame sections, where there are the smallest lateral forces will be provided with the best conditions for the mutual displacementelements of the lining of the castles and compliance.

In order to establish the location of these cross sections were calculated for arch support. We considered two design models: two-hinged and hingeless arch support.

In writing this essay master's work is not yet complete. Final completion: December 2012. The full text of the and materials on the topic can be obtained from the author or his head after that date.

The calculations showed that the frame section, which are the largest longitudinal forces and lateral forces are zero, are separated by a distance φR (φ – the angle between the radiuses R, drawn through these section).

The angle (φ depending on the angle of occurrence of species ranges from 70° to 100°. axis of symmetry of these sections is rotated about the vertical axis of the frame for 10-15° in the direction normal to the stratification of rocks.

Completed research allowed to develop and patent the design of lining [2] (pic. 4).

Рic. 4. The proposed design of roof support: 1 и 2 – racks support;
3 – an integral element of the top up; 4 – the top up; 5, 6 и 7 – sites
compounds bearing elements.

In the proposed design elements that form an integral verhnyak in place of their compounds are the top node of compliance so that their ends are parallel to bedding, as a resultWhat this site is working when exposed to only the lateral loads. The ends of the racks and composite verhnyaka at the point of connection nodes of compliance side arranged in a line parallel to the direction of the principal stresses. Therefore, the side nodes of compliance work only when exposed to loads acting perpendicular to the bedding. differentiated andcoordinated work sites yielding eliminates oblique loads at the nodes of compliance, as well as provide them with a coherent long-term work.

The developed design of the side nodes of compliance are equidistant from the top. As a consequence, the elements of the composite verhnyaka have the same dimensions, and their size remains unchanged atany occurrence of the species - will only change the size of racks. Standardization in the manufacture of composite components verhnyaka, will reduce the cost of their production.

The assembly of metal supple support is carried out as follows. First, connect the rack to a composite element verhnyaka 3 with host susceptibility 5. Then drill holes for the rack 2 andcollected for the previous part of the design. Install the rack in the design position. After that, pick up an element of the compound 4 in verhnyaka design position and connect the elements of the lining in a single structure with nodes yielding 6 and 7.

Using the proposed design will allow for a coherent account of all sites to ensure compliance of long-lining performance, increase the stability of production, lower costsits maintenance and construction elements of support

Another possible way to increase efficiency of metal arch support is the use of combined roof supports, including through the use of anker systems.

Literature

1. Кошелев К.В., Петренко Ю.А., Новиков А.О. Охрана и ремонт горных выработок. – М.: Недра, 1990. – 218 с.
2. Касьян М.М., Новіков О.О., Петренко Ю.А., Шестопалов І.М., Рєзнік А.В. Металеве податливе кріплення – Патент на корисну модель № 64368, зареєстр. 10.11.2011р. – 7 с.
3. Абрамсон Х.И. Тенденции развития техники крепления горных выработок на шахтах //Уголь Украины. – 1985. – № 2. – С. 42-43.
4. Аносов А.С, Коршунов В.Н., Кривцов И.И. Зависимость устойчивости штрека от способа его проведения //Уголь. – 1978. – № 10. – C. 26-27
5. Смирняков В.В., Подолян В.К. Совершенствование конструкций металлических крепей горных выработок. //Шахтное строительство. – 1985. – № 4. – C. 26-28
6. Рева В.Н., Абросимов В.М. 0 совершенствовании способов повышения устойчивости горных выработок //Шахтное строительство. – 1983. – № 8. – C. 9-11.
7. Гайко Г.И. Обоснование способа и параметров усиления арочной крепи подготовительных горных выработок: дис. Канд. Техн. Наук.-Алчевск, 1994 – 148 с.