Cross-section of the roadway. Carrying out mine workings. The shape and dimensions of the cross-section of the workings

1) Width of production in the light according to the passport "Kryvbas project":

Vsv \u003d 750 + 1350 + 450 + 1350 + 1000 \u003d 4900 mm.

2) Working width in black:

Vvch \u003d 4900 + 2 60 + 200 \u003d 5220 mm.

3) Clearing height:

Нсв \u003d 1850 + \u003d 1850 + 1650 \u003d mm.

where: \u003d B / 3 \u003d 1650

4) Height of working out in black:

Нвч \u003d Нсв + \u003d 3500 + 60 \u003d 3560 mm.

5) Sich production in the light

Sc \u003d Wsw (+ 0.26 Wsv) \u003d 4900 (1650 +0.29 4900) \u003d 14300 mm2 \u003d 14.3 m2

6) Sich production in black:

Svch \u003d Vvch (+ 0.26 Vvch) \u003d 5.22 (1.65 + 0.26 5.22) \u003d 15.70 m2

7) Siceness of working out in sinking of sinking:

Spr \u003d Vvch (1.02 h 1.05) \u003d 15.70 1.05 \u003d 16.48 m2

Cross-section of the projected mine

The main standard sizes of production:

  • 1. Working height in the clear, Нсв. 2200mm.
  • 2. Rough working height, Нвч. 2230mm.
  • 3. Width of working in the light, Vsv. 2200mm.
  • 4. Rough working width, Vvch, 2260mm.
  • 5. The height of the box vault, hw 1450mm.
  • 6. Thickness of the roof support, d0 30cm.
  • 7. Thickness of the wall of the support, dс 30cm.
  • 8. Large radius of curvature of the box vault, ?? 1522mm.
  • 9. Small radius of curvature of the box vault, ?? 576mm.
  • 10. Cross-sectional area of \u200b\u200bopenings, Sс 4.4 m2
  • 11. Cross-sectional area of \u200b\u200bthe working in the rough, Svch 4.5 m2
  • 12. Cross-sectional area of \u200b\u200bthe mine working in the heading, Spr 2.1 m2

Carrying out with separate excavation of layers of rocks or coal and enclosing rocks - a scheme in which, first, a coal seam or a certain layer is removed for a certain excavation, and then the enclosing rocks or other layers. Carrying out a wide face - a scheme in which coal is excavated outside the section of the mine with placement of waste rock in the formed space. The use of domestic combines is advisable when carrying out mine workings along a coal seam with a small percentage of undercut of rock with a hardness of f up to 7 and an angle of inclination up to ...


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LECTURE No. 19

Mine workings (part 1)

General questions of carrying out workings.

Mining - a complex of processes for breaking, loading, transporting rock mass, erecting support, ventilation, building up transport devices and communications. Providing movement of the preparatory face.

Way of carrying out production- a set of technical solutions for breaking, loading rock mass and fixing the face, the implementation of which allows the development to be carried out in certain mining and geological conditions. The methods of carrying out are divided into ordinary and special.

The usual ways - ways of carrying out workings in stable rocks, allowing them to be exposed for a certain time.

Special methods- ways of carrying out workings in loose rocks and rocks with suspended water cut.

Technological scheme of production- a definite, interconnected in space and time, order of execution of production processes, means of their mechanization and the placement of equipment corresponding to this order

Technological schemes for carrying out workings are subdivided into:

  • Driving schemes for homogeneous rocks;
  • Driving patterns for heterogeneous rocks.

Homogeneous breed - breed, the strength of which is approximately the same throughout the slaughter.

Heterogeneous breed - a set of layers of rocks, the properties of which are different in the section of the working face. A typical example of a heterogeneous rock carrying out coal mining with a hairstyle of roof rocks. (soil)

Continuous slaughter - a scheme for the development, in which the breaking (excavation) of rocks is carried out simultaneously along the entire face.

Conducting with a split notchlayers of rocks or coal and host rocks – a scheme in which, first, a coal seam or a certain layer is removed to a certain cut, and then the enclosing rocks or the rest of the layers.

Carrying out a narrow face - a scheme in which the rock mass is excavated only within the limits of the cross-section of the working.

Carrying out wide slaughter - a scheme in which coal is excavated outside the section of the mine with placement of waste rock in the resulting space.

The shape and dimensions of the cross-section of the workings

Section of production - an image on the drawing, on a certain scale, of the contour of the working, support, equipment, tracks and communications, obtained as a result of crossing the working by a plane. Sections differ in the type of section planes. For a longitudinal section, the cutting plane runs along the axis of the excavation. For a cross-section, the cutting plane is perpendicular to the axis of the excavation.

Cross-section in penetration - section of the working after the rock mass has been excavated before the installation of the lining along the contour of the enclosing rocks.

Rough section - section along the outer contour of the support and the working soil.

Light section - the section after the erection of the support and the laying of the rail track along the inner contour of the support and the top of the ballast layer, and in its absence - along the soil.

The cross-sectional shape of the mine is determined by:

  • Properties of rocks;
  • The magnitude and nature of the manifestation of rock pressure;
  • Support structure;
  • By appointment;
  • The service life of the production;
  • The way of carrying out the development.

Depending on the shape of the cross-section, the workings are: rectangular (a), trapezoidal and polygonal (b-e). Horizontal workings are usually secured by wood, metal or prefabricated/ b support.

A vaulted cross-sectional shape (e-m) has workings fixed by an arched or w/ b support.

Vertical workings are most often rectangular (a) or round (n) and are fastened with concrete or tubing support.

The cross-sectional area of \u200b\u200bthe mine is determined by:

  • Dimensions of operational equipment or vehicles;
  • Clearances between support contours and vehicle equipment dimensions;
  • Clearances between the dimensions of equipment and vehicles;
  • The dimensions of the passage for people.

All clearances are given in §88 PB.

For the movement of people in the development, a passage is left with a width of at least 0.7 m at a height of 1.8 m from the sidewalk, the top of the ballast layer or the soil.

The minimum cross-sectional area of \u200b\u200bthe mine is 4.5m2 (§88 PB)

  • The amount of air that is planned to be supplied to the production.

Materials for fixing mine workings.

The following materials are used for supporting mine workings:

  • Metal; Concrete; Reinforced concrete; Wood; Brick; Plast concrete; Carbon fiber;
  • Fiberglass; Dr. polymer materials.

Metal - for mine lining, they are used in the form of profiled rolled products made of low-alloy or low-carbon steels (Art.5)

SVP 6 standard sizes with a weight of 1 running meter are produced. 14,17,19,22,27, and 33 kg.

In addition to rolled metal, metal tubing is produced - segments with a curved plate (wall) and stiffeners.

Concrete - artificial stone material containing binders (cement, gypsum cement), fine aggregate, coarse aggregate and water.

Sand is used as a fine aggregate, strong gravel or crushed stone is used as a coarse aggregate.

The composition of concrete is determined by the content of the weight parts of cement, sand (A) and coarse aggregate (B)

1: A: B

And also according to the ratio of the mixed amount of water (B) and cement (C) B/ C

Cement grade - ultimate compressive strength of the sample in tenths of MPa, made from one part of cement and three parts of sand at B/ C \u003d 1: 2.5

The most widely used are Portland cements of grades 400, 500, and 600 (less often 300)

At a cooking consumption of 1m3 concrete less than 200 kg concrete is called lean;

200 - 250kg - medium

More than 250kg - fat.

Reinforced concrete - a single artificial metal-stone material consisting of concrete and metal reinforcement.

Forest materials - used for fastening workings with a service life of 2 - 3 years.

Pine, spruce, fir, cedar, larch are used to fasten the workings.

The main type of timber lining is ore rack ø 7 - 34 cm, length 0.5 - 7 m.

Lumber : cuts, beams, slabs, boards are obtained by sawing ores of racks (logs).

The specific tensile strength of timber is~ 10MPa, compression - 13MPa.

Brick - grades 150 and 175 are used to secure workings; density of brick in masonry 1800kg/ m 3.

Concreteites - concrete stones made of ordinary or silicate concrete and blast-furnace slags. Betonite grade - not less than 150.

LECTURE number 20

Carrying out mine workings (Part 2)

The concept of processes and operations when carrying out preparatory workings

Process - work clearly defined in terms of its technical and organizational content, consisting of separate parts (operations) performed in a certain sequence.

Operation - a set of working methods, characterized by the constancy of the place of performance and performers.

Main processes - processes that are carried out directly at the working face and have their purpose to change the shape and condition of the face (separation of the rock mass from the massif and fixing the face).

Supporting processes - processes that ensure the efficient and safe implementation of the main ones.

The main and auxiliary processes can be performed sequentially or combined.

Based on the possibility of overlapping in time, they are distinguished:

  • flow technology (PT);
  • cyclical technology (CG).

Flow technology is a technology in which the execution of the main processes (operations) is combined in time.

Cyclic technology is a technology in which the execution of the main processes (operations) is carried out sequentially.

Driving cycle and its main parameters

Driving cycle - a set of processes and operations, as a result of which the face moves for a certain time at a distance specified in the passport.

Cycle time - the time during which all the main technological processes of the tunneling cycle are carried out.

The duration of the driving cycle is usually taken as a multiple shift, which simplifies the organization of work.

Borehole advance per cycle - the distance that the face moves after all the processes included in the cycle have been completed.

Conducting horizontal and inclined mine workings

in rocks of strong and medium strength

The technology of carrying out mine workings in rocks with a fortressf more than 6.7 includes processes:

  • drilling and blasting operations (blasting);
  • ventilation of the face and bringing it to a safe state;
  • construction of temporary support;
  • loading of rock mass;
  • erection of permanent support;
  • auxiliary work.

The following requirements apply to blast-hole drilling:

  • uniform crushing of the rock mass;
  • a small waste of rock from the face.

The blasthole parameters are determined for each bottomhole individually and are recorded in the blasthole passport.

After the production of blasthole blasting and airing, the construction of temporary support is started (a structure that ensures safe work in the preparatory face before the construction of a permanent support).

For loading the broken-off rock mass, special rock-loading machines are used on caterpillar or wheel-rail vehicles.

The chipped rock mass can be loaded directly into the trolleys or stepwise through special design loaders.

Support of mine workings (erection of permanent support)

Depending on the type and material, the support is divided into:

  • metal;
  • reinforced concrete;
  • wooden;
  • stone;
  • anchor;
  • mixed, etc.

According to their characteristics, supports are rigid and pliable.

Rigid supports - the total deformation should not go beyond the elastic limits. Typically, these supports are used in workings with steady rock pressure.

Pliable - roof supports with special yielding nodes, due to which the amount of displacement of the support elements exceeds the value of elastic deformations.

In recent years, the most widespread has been anchor support, which makes it possible to increase the stability of the roof and sides of the working by "stitching" several layers with special rods. Fixation of the anchor lock part in the rocks occurs with the help of metal structures or concrete, polymer compositions.

To fasten workings in zones of heaving rocks, a lining is used with the addition of a "bed" - an additional element that closes the lining contour from the side of the soil.

To prevent rocks from falling out from the side of the roof, lattice, wooden, polymer or reinforced concrete tightening is used.

After the completion of the main cycle, the auxiliary processes begin:

  • extension of vent pipes;
  • downhole conduit;
  • rail tracks, scraper conveyor;
  • slanting of the face and development.

After the completion of the auxiliary processes, the tunneling cycle is repeated.

Dignity drilling and blasting method:

  • wide range of applications;
  • the possibility of conducting shaking blasting on outburst-hazardous formations.

disadvantages drilling and blasting method:

  • multi-operation technology;
  • relatively low rates of excavation;
  • additional danger in the conduct of blast-blowing.

Combine mining method

The main difference between the shearer method of carrying out workings from blast-hole blasting machines is the possibility of combining the process of breaking the rock mass and shipment by a roadheader.

The most widespread are crawler-type roadheaders with arrow-shaped crown-type executive body and a scraper loader.

Diagram of a tunneling machine for selective action. 1- hammer bit, 2- executive body, 3- hydraulic jack, 4-body, 5-electrical equipment, 6-control bullets, 7- scraper conveyor, 8- rear support cylinder, 9- undercarriage, 10- front support cylinder, 11 -loader.

The use of domestic combines is advisable when carrying out mine workings along a coal seam with a small percentage of undercutting of rock with a hardnessf up to 7 and an angle of inclination up to -200 and up to +20 0 by uprising.

The chipped rock mass is loaded onto a scraper or belt conveyor directly by a combine harvester or using a special reloader.

Dignity combine method:

  • low-efficiency;
  • high rates of penetration;
  • ensuring the safety of mining operations.

disadvantages combine method:

  • limited range of application (fall, uprising).

LECTURE No. 21

Cleaning work in coal mines

The cleaning work includes the following processes: extraction and transportation of PI;

face fastening; roof management.

Cleaning excavation - a set of processes of breaking (separation from the massif), loading the broken off rock mass onto the downhole vehicle, delivery of PI from the face to the transport mine.

Production face - mine workings intended for the extraction of PI.

Distinguish between long longwall faces (lavas) and short (runways and chambers).

Long face - an extended longwall working of a linear or ledge shape, one side of which is bounded by a coal massif, and the other - by support at the border with the worked-out space; the roof and soil are enclosing rocks.

In long working faces, coal is excavated according to flank and frontal schemes.

Flank scheme - coal is separated from the massif in a narrow section (at one point) of the working face.

Frontal scheme - movement of the shearer perpendicular to the direction of the face movement and take out a strip of coal of a certain width (working width). With the frontal scheme, separation from the massif is carried out by an extraction unit simultaneously along the entire length of the working face. The direction of movement of the unit in this case coincides with the direction of movement of the working face.

The following are distinguished according to the working width:

  • narrow-cut excavation - 0.5 - 1.0 m;
  • wide-cut - more than 1.0 m;
  • plow - 0.03 - 0.15 m.

With narrow and wide-cutting excavation, the coal is separated from the massif by cutting, with plowing - by spalling.

Short production face - working with a face of a short length, bounded on the sides by a coal massif or coal pillars. Transport and ventilation workings adjacent to the stope are called excavation workings.

According to the location of the production faces relative to the bedding elements, production faces are distinguished: by the fall; along strike; on the uprising; across the stretch; diagonal.

Coal transport production faces are made:

  • in long working faces of shallow and inclined seams - by scraper conveyors or conveyor-circular extraction units;
  • in long working faces of steeply inclined and steep seams - by gravity along the soil; by gravity along special grooves; conveyor lines of extraction units;
  • in short working faces - by scraper conveyors, LHD machines (self-propelled trolleys), hydrotransport.

Layout of equipment in the longwall:

1 - top drive head of the face conveyor;

2 - upper niche; 3- becoming the face conveyor; 4- narrow-cut shearer; 5 - executive body of the combine; 6 - lower niche; 7 - bottom drive head of the face conveyor; 8 - A face conveyor in a transport tunnel.

Roof control methods in working faces

Roof management - a set of measures to regulate the load on the lining of the working face, carried out for the effective and safe extraction of PI.

There are ways to control the roof: complete collapse; partial collapse; partial bookmark; full bookmark; smooth lowering.

The method of complete collapse of the roof

The method is recommended for medium and easily crumbling rocks of the immediate roof, when their thickness is sufficient to puff up the main roof. When removing the bottomhole (powered) support in the worked-out space, the roof rocks collapse. The step of the primary planting is moving the working face away from the split furnace (assembly chamber) until the rocks of the main roof collapse. This is the most common way to control roof collapse. If self-collapse of the roof rocks during movement does not occur (hovering), then a forced landing is used, for example, blast-hole.

disadvantages : Difficulty with hard-to-break roofs;

  • impossibility of using objects on the surface when working out.

Partial collapse method Recommended for use in the presence of easily collapsed rocks of the immediate roof of low thickness and the tendency of the rocks of the main roof to periodic collapse.

With this method, rubble strips being constructed with a width of 4-6 m are used, the distance between strips is up to 15 m.

Partial bookmark method mined-out space is used for difficult-to-break rocks. Rubble strips are being erected to restrain the collapse of the roof rocks. On gentle seams, rubble strips are located along the strike, on steep ones - both along the strike and along the dip.

Full bookmark method it is recommended, if necessary, to prevent the collapse of the enclosing rocks after the extraction of the PI. It is used when it is necessary to prevent subsidence of the earth's surface.

A full bookmark allows you to:

  • avoid subsidence of the earth's surface;
  • avoid air leaks into the worked-out space;
  • reduce the chance of rock bump

disadvantages - high labor intensity and cost of work.

Smooth lowering method Roof rocks are used on seams up to 1.2 m thick with swollen soils and weak roof rocks, prone to smooth sagging.

LECTURE No. 22

Cleaning work when mining flat and inclined seams

Features of clean-up work in the development of flat and inclined seams

The main features that characterize the technology for mining flat and inclined seams are:

  • Good conditions for the use of modern technical means, in particular, means of complex mechanization;
  • The possibility of using the method of controlling the roof with complete collapse
  • Possibility of using effective ventilation and gas control schemes to achieve high loads on the working face;
  • Ample opportunities for partial and complete automation of cleaning works.

Longwall Longwall Cleaning

The main technologies for the development of flat and inclined seams with long working faces are:

  • Complex - mechanized coal mining (75%);
  • Extraction by narrow-cut combines with individual support (6%);
  • Coal extraction by plows with individual support (2%);
  • Extraction of coal by wide-cut miners with individual support (2%);
  • Extraction of coal on explosives with individual support (10%);
  • Coal extraction with jackhammers with individual support (1%);
  • Other technologies (auger, etc.). (four%).

Coal mining with a narrow-cut shearer with individual support and as part of OMK

The complex is a set of certain mining equipment, transport equipment and mechanized support, linked according to the main technical parameters.

Complexes, consisting of:

  • Narrow-grip mining machine (harvester or plow);
  • Bending face conveyor;
  • Hydraulic downhole support;
  • Hydraulic support of joints.

Mining harvester Is a combined mining machine that simultaneously performs work on separating coal from the massif, crushing it and loading it onto the face conveyor. The executive body of the narrow-grip harvester is the auger, which is a screw Ø 0.56 - 2.0 m (diameter along the cutters) on the projections of which cutters are installed in special tool holders (knuckles). When the auger rotates, the cutters separate the coal from the face, and the auger blades load the broken off coal onto the scraper conveyor. The harvester can move on the ground or on the AFC frame. Combine-harvesters working from mine workings are used in very thin and thin layers. The harvester working from the face conveyor frame on the face side has support skis and grips that do not allow the harvester to move when removing coal.

The harvester moves along the table of the face conveyor while rolling the lantern wheel along the rail fixed on the bottom hole or fixed on the heads of the peak chain conveyor. When mining thin seams, along with miners with auger executive bodies, miners with drum executive bodies are used. Loading of coal using drum executive bodies is carried out using special loading plates.

Extraction of coal in a longwall equipped with a narrow-cut shearer is carried out as follows. In the initial position, the combine is brought into the niche 6, the conveyor and the support are moved to the bottom, the niche 2 is formed. The harvester begins to move upward with the removal of a strip of coal. Following the harvester, the support moves with a certain lag. After the harvester leaves the upper niche, the harvester starts moving downward with soil stripping. Following the harvester with a lag of 10-12 m, the conveyor moves in. When the harvester returns to the bottom of the longwall, the cycle repeats. This scheme of coal extraction is called one-sided. With the shuttle scheme, coal is excavated when the combine moves in both directions.

Extraction cycle - a set of processes and operations, and periodically repeated during coal extraction along the entire length of the working face, after which the face moves to a certain distance. A scraper conveyor is used to transport coal along the longwall. The scraper conveyor consists of: Traction body; Reshtachny stav; Natural stations (stations); End station.

The operation of the scraper conveyor is based on the principle of moving the load by dragging when an endless chain with scrapers moves along special grooves (pans). According to the method of movement, following the movement of the working face, the conveyors are divided into bending and portable. Bending conveyors allow you to move without disassembly by standing at a distance of up to 1 m in the range of length 10-15 m.

Fastening of the production face - the process of installing special structures supporting the roof (and soil), providing conditions for the safe work of people and the efficient operation of mining equipment. The following types of face support are used: Individual face support; Landing at bottom-hole support; Sectional powered support; Complete powered support; Aggregate powered support.

Individual support consists of struts installed between the roof and the soil, and tops, installed between the roof and the support. The frame consists of a top and one, two or more struts. Upper seams can be oriented along the dip or along the strike of the formation. The roof of the excavation between the tops is tightened with a tightening.

Individual roof supports can have different designs and dependencies between the reactionh and drawdowns ∆ h. Lining stiffness tgβ \u003d h / ∆ h; Support flexibility ∆ h / h;

According to A.A. Borisov, all supports are divided into three types:

Type I - 0 support the growing resistance, they haveh \u003d ƒ (tgβ);

Type II - tg \u003d 0 - support of constant resistance, they haveh \u003d const;

Type III tgβ → ∞ - rigid supports. R H - the initial resistance created in the rack when it is installed;R P - working resistance - the average value of the maximum allowable resistance of the rack to lowering the roof.

Under the influence of the pressure of the roof rocks, the length of the strut is reduced by the amount of strut landing. After the maximum landing, the bearing capacity of the strut is exhausted and its destruction begins.Powered roof support a working face is called a moving mechanically hydraulic support, consisting of kinematically interconnected bearing support and enclosing elements. Powered roof support is designed for mechanized roof fastening and support movement.

LECTURE No. 23

Cleaning work on steep and steep seams.

Features of cleanup work on steeply inclined and steep seams

  1. The possibility of using gravitational coal transport along the face during mining along the strike and along adjacent workings when mining along the dip.
  2. The need for fixing both the roof and the soil when carrying out cleaning work.
  3. Complexity of mechanization of cleaning works on steeply inclined and steep seams.
  4. Difficulty ventilating production faces, caused by large air leaks due to the presence of aerodynamic connection with the surface.

Increased fire hazard in the development of steeply inclined and steep seams, caused by large losses of coal.

The main technological schemes development of steep and steep seams are:

  • Ceiling-ledge face along strike when mining coal with jackhammers;
  • Straightwall face along strike with coal extraction using explosives;
  • Rectangular faces along the strike when mining coal with narrow-cut shearers and conveyor-plows;
  • Straight-line faces along the fall when extracting coal with units with conveyor - plows.
  • Development panel system.
  • Hydraulic technologies in the RGO version.

Development of steeply inclined and steep seams with a ceiling slaughter

In each ledge, coal is excavated in strips equal to the width of the ledge. For coal breaking, pneumatic breakers are used: ОМ 5ПМ, ОМ 6ПМ and ОМ 7ПМ. To ensure safe working conditions, the ledge is protected from the flow of broken coal in the upper part from the overlying ledges by boards. Coal mining in the ledge is carried out from top to bottom, with the obligatory fastening of the overhanging coal massif of ore with racks and boards. When the face lining is installed in the form of one or two rows of ore racks for growing. In case of weak soil, the racks are installed on wooden planks. In ceilings, the following roof control methods are used:

  • Full collapse (0.6 - 1.3 m).
  • Smooth lowering (0.5 - 0.7 m).
  • Bookmark (1.3 - 2.2 m).
  • Hold on fire (0.6 - 1.4 m).

Development of steeply inclined and steep seams by straight face along strike

Coal extraction is carried out by specialized shearers, the face is fastened with a hydraulic block, the orientation system of which is adapted to large angles of incidence. The face is inclined towards the movement by 10-150 ... The lava is divided into an upper combine (approximately 2/3) and a lower magazine part.

Coal extraction in the upper part is carried out by miners of the "Temp" and "Search" type from the bottom up. Moving the harvester along the face is carried out by a winch rope installed on the ventilation drift. Along with the working rope, a safety rope is used to hold the harvester in the event of a break in the working rope.

The lower part of the longwall is made in the form of one or three store benches, 10 m long and 6 m wide, which serve for the accumulation of chipped coal.

For the development of steep and steeply inclined seams, the KGU-D complex (0.6-1.5 m) and the AK-3 unit (1.6-2.5 m) are used.

Development of seams by straight face, moving downward

Downhole mining can be carried out by units of type 1 ANSCHMK and 2 ANSCHMK in the power range of 0.7 - 2.2 m. The length of the working face is 40 - 60 m.

The ventilation oven is formed as the unit moves behind the fur lining

The structure of the panel extraction unit includes: Powered roof support; Hydraulic equipment; Electro (pneumatic) equipment; Remote control equipment.

The conveyor saw is an endless round-link saw-chain on which carriages equipped with cutters are fixed. The chain moves along a special guide beam. First of all, a pack of coal is removed from the roof. After that, when it is introduced into the massif due to the hydraulic feed jacks, the coal is destroyed by the cutters, and the coal is transported to the coal-firing furnace due to the translational movement of the carriages. The movement of the unit is carried out by removing the thrust from the sections and moving them down the fall to the conveyor belt.

Development panel system Scopem\u003e 2.0 m and a\u003e 55 0.

Shield support - mobile structure,consisting of metal beams, forming a "frame" along the perimeter of the section, a knurler made of beams, ties and clamps connecting the structure into a single whole.

Separate sections are interconnected by rope segments. The boards consist of 4-5 sections. Each section has a strike dimension of 6.0 m.

Shield support protects the face from falling rocks and takes their load. Coal extraction under the shield is carried out using explosives. Excavation of coal consists of: expansion of the shield ditch; blasting support pillars; landing shield.

Panel development systems are widely used in the Prokopyevsko-Kiselevsky region of Kuzbass and in the mines of the Far East.

LECTURE No. 24

The concept of the technological scheme of the mine

General concepts and definitions

Mine technological scheme (TSSh)- a set of mine workings, surface buildings and structures with machines and mechanisms placed in them, the joint work of which ensures efficient and safe coal mining.

The main elements of the TSS are:

Clearing faces; Preparatory slaughtering; Mineral transportation system; Delivery system of people, materials and equipment; Backfill feed system; Ventilation system; Drainage system; Coal seam degassing system; Mine lift. The parameters of each of the elements are selected (calculated) in such a way as to maximize coal production. An element of the technological scheme that restrains coal mining is usually called"Bottleneck" in the TSSH.

Purification Conv. Transport Ventilation Rise

bottomhole to the borehole 2000 t/ day 1500 t / day

A day \u003d 2000 t / day A day \u003d 2500 t / day

Low place of TSSH.

Main transport

The main transport is understood as a set of technical means, mine workings and underground structures that ensure the delivery of coal from the excavation site to the OSD or to the surface.

In the system of general mine transport, belt conveyors with a wide belt of 800, 1000, 1200 mm are most often used.

Modern belt conveyors have a delivery length of 500-1500m and work in workings with inclination angles from -16 to +25 .

The capacity of the belt conveyors is 420 - 1600/ hour.

To increase the reliability of the conveyor lines, intermediate bunkers with a capacity of 50-300 m are arranged between the conveyors.3 ... The power of the drives is 50-250 kW.

Along with belt conveyors for transporting coal along horizontal workings, a number of mines uselocomotive haulage.

When using locomotive haulage, minerals, rock and other materials are transported in mine cars, which move along rail tracks with the help of locomotives.

The rail track consists of a ballast layer along the roadway soil, sleepers, rails and their connections.

The ballast layer consists of rubble and serves as a shock-absorbing base.

Sleepers are used to connect the track in a common track, and there are metal, wood and reinforced concrete.

Track width - the distance between the inner edges of the rail heads. The standard track width is 600-900mm.

Main characteristic of rails - weight is 1 meter. Use rails with a mass of 24.33.48 kg/ m.

Mine cars are divided into the following types:

  • Freight trolleys;
  • Human trolleys;
  • Trolleys and platforms for transporting materials and equipment;
  • Special purpose (repair, track measuring)

By the method of unloading, the trolleys are divided into:

  • Trolleys with a blank body (unloaded by overturning) VG;
  • Self-unloading trolleys with hinged bottom - HP type;
  • Self-unloading trolleys with a folding side WB (UVB);

Modern trolleys have a capacity of 0.8 - 3.3m3 , the most common container is 2.4 or 3.3m3 .

Locomotives by type of energy are divided into:

  • Contact electric locomotives;
  • Battery electric locomotives;
  • Diesel carts;
  • Hydrocarts;
  • Air carriers (pneumatic locomotives).
  • The most widespread are electric locomotives. (diesel wagons on sh."Osinnikovskaya aya").

When using contact electric locomotives, electricity is supplied through the conductor of the contact network (trawl) and the current-carrying rail. The electric vehicle is equipped with a DC motor with a voltage of 250 V. The mass of contact electric locomotives is 7, 10, 14, 20, 25 tons. The speed is up to 25 km / h.

Contact electric locomotives are used in non-gas mines, as well as in the fresh stream of minesI – II categories.

Accumulator electric locomotives receive electricity from accumulator batteries. Coupling weight 7, 8, 14 t, travel speed up to 14 km / h.

Transportation by self-propelled trolleys

The self-propelled trolley moves along the roadway on 4 or 6 wheels with pneumatic tires. El energy is supplied through the cable. Diesel trolleys are also used. To speed up the process of unloading and loading, a scraper conveyor is built in the bottoms of some cars.

Hydraulic and pneumatic transport

It is used for coal transportation and filling material supply.

Auxiliary transport

For the delivery of people, materials and equipment are used:

  • Locomotive haulage.
  • Specially equipped conveyor belts and blank belts of conventional conveyor belts.
  • Tramming with end rope.
  • Tramway with an endless rope.
  • Monorail roads.

Mine lift

To provide transport links with transport horizons, mine hoisting units are used.

The main lifting unit is designed to deliver the mined PI to the surface.

Auxiliary lifting unit - for lowering and lifting people, materials, equipment, issuing waste rock.

Human lifting equipment - designed exclusively for lowering and lifting people.

The following elements are referred to mine lifting:

  • Lifting machines;
  • Lifting vessels (skips, crates);
  • Hoisting ropes;
  • Necessary barrel reinforcement (executions, guides, grips);
  • Loading and unloading devices;

Mine pile driver is installed directly above the barrel and serves to accommodate the guide pulleys.

Lifting machine it is installed at a certain distance from the trunk and serves to move the vessels by winding traction ropes onto the drive drum, to which these vessels are suspended.

Hoisting ropes are made of high-strength steel wires, wound in a special way on a hemp or steel core. The diameter of the ropes is determined by calculation and is 18.5 - 65mm, the diameter of the steel wires is 1.2 - 2.8mm. Ropes of lifting equipment for lowering - lifting people must have a safety margin of at least 9, for cargo lifts - at least 6.5.

In vertical shafts, lifting vessels are:

  • Mine skips;
  • Tilting stands;
  • Non-tilting stands;

If one vessel is suspended from the lifting machine, then the lifting is calledsingle-stand (one skip), if two -two cage or two skip.

To direct the movement of the lifting vessel, special structures are hung in the barrel -conductors , which are attached to transverse spacing, executions.Lifting vessels have specials. supports enclosing conductors.

The lifting vessels have special braking devices calledparachutes ... When the rope is let in or broken, the parachutes are captured by the guides or specials. brake ropes, keeping the vessel from falling.

Along with the purpose, lifts are classified according to the type of lifting vessels into: lifts with non-tipping stands; Lifts with tipping stands; Skip climbs.

Tipping stands differ from non-overturning the fact that the loaded trolleys on the surface do not roll out of the cage, but are unloaded into the receiving hopper when the cage turns (tilts).

In large modern mines, the main thing, as a rule, is the skip lift.

When skip lifting the rock mass is reloaded into a special vessel called a skip. On the surface, the skip is unloaded by dumping or through the bottom.

Skip consists of from the frame and body. For skips unloading through the bottom, the body is rigidly connected to the frame. In dumping skips, the body is pivotally connected to the frame and unloaded by turning around the axis when the skip reaches the unloading curves.

Technological complex on the surface of the mine

Mine pile driver , metal or reinforced concrete, is erected directly above the mouth of the trunk. The height of ordinary headframes is 15 - 30m, tower headframes - up to 100m.

Conventional pile drivers are used to accommodate guide pulleys and guides, attach relief curves and landing devices.

Tower pile drivers made of concrete or reinforced concrete in the upper part have a machine room for a lifting machine with a friction pulley.

Pithead - directly adjacent to the headframe and serves to ensure the operation of the mine hoist. The sorting building is designed for preliminary screening and sorting of coal by size. Instead of sorting, a processing plant may be located on the territory of the mine.

Overpasses, conveyor galleries and bridges - structures for the laying of narrow potassium rail tracks and the installation of belt conveyors. Depending on the purpose, these structures can be open or closed, horizontal or inclined.

Receiving and loading bins are metal or concrete structures designed for short-term storage of minerals.

Waste dump - the area of \u200b\u200bthe surface allocated for the storage of waste rock.

Mine ventilation system

Ventilation system mines - a set of mine workings of ventilating installations and ventilation structures in the mine and on the surface, providing stable and efficient ventilation.

The ventilation method is determined by how the fan works:

Suction - suction method.

For injection - injection method.

One for suction, the other for discharge - combined method.

Ventilation scheme is determined by the direction of movement of the ventilation stream.

Central scheme provides for the supply of a fresh air stream and the outlet of the outgoing one is carried out along the closely located main opening workings.

Flank scheme provides for the supply of fresh and removal of the outgoing jet through the main opening workings located in different parts of the mine field.

Combined scheme is a combination of the two above.

Ventilation system can be single or sectional.

With sectional - the mine is divided into separate, separately ventilated areas.

With a single scheme the shaft is ventilated without dividing into separate sections (sections).

Mine fan units

A mine fan unit serves for continuous supply of fresh air to the mine and consists of: Working fan; Standby fan; Ventilation ducts; Devices for measuring the direction of air movement; Electric motors; Control and recording equipment; Air handling unit building. Mine fan installations have a capacity from 3 - 5 to 20 - 25 thousand. m3 min.

Depression (compression) of the fan - the difference in pressure at the fan exhaust and atmospheric pressure.

Modern fans create a pressure (depression) of 470 - 700 daPA.

Mine fan structures

According to their purpose, fan devices are subdivided into: Blind lintels for isolation of mine workings; Ventilation locks with doors, windows or methods to regulate the air in mines; Crossings (air bridges) - ventilation structures for separating air jets in intersecting workings;

Control over air distribution and the state of the mine atmosphere

Control over the air distribution and the state of the mine atmosphere is carried out by the mine engineers and employees of the ventilation and safety section (VTB).

To control the composition of the atmosphere, mine interferometers ShI10, ShI11, gas detectors of the GKh type, devices of the type"Signal". To control the air flow, anemometers of the ASO-3, MS-13 and APR-2 types are used.

Acceptable contentCH 4 and CO 2

CH 4%

CO 2%

Ref. From a longwall or dead-end mine

Ref. Wings (mine)

Incoming jet into the workings and the faces of the blind workings

Rock physics as a science basic concepts and definitions 2. Rock physics as a science basic concepts and definitions Rock physics petrophysics is one of the main disciplines of exploration geophysics most closely related to the physics of substances and petrology. Of the many physical properties of rocks, petrophysics studies mainly the properties that create physical fields that can be measured by geophysical methods.
9132. MAIN PROPERTIES OF ROCKS 21.78 KB
Classification of properties of rocks. The number of physical properties of rocks manifested in their interaction with other objects and phenomena of the material world can be arbitrarily large. In geomechanics, knowledge is required, first of all, of mechanical and density properties, but at the same time, some other properties may be of interest and indicators of which quite clearly reflect the state of the rocks or clearly correlate with stresses in the rock mass and therefore can be used to assess ...
1639. GEOMECHANICAL SUPPORT OF MINING WORKS 13.98 MB
Rocks with a strength of 3050 MPa, under the influence of mining operations, when the stress increases by 23 times in comparison with the stresses in the massif untouched by mine workings, lose their strength. This phenomenon was not observed at shallow depths, that is, we seem to work in conditions of less durable rocks. In connection with the projected increase in rock displacement into the working three times at a depth of 1000 m compared to a depth of 500 m, a significant increase in the volume of repair work should be expected. Which of the above we know what's new in the course ...
1627. Destruction of rocks by explosion 55.26 KB
The characteristics of the development and the conditions for its implementation: Name crosscut. The sectional shape of the mine is trapezoidal. Estimated cross-section of working out in the rough - 116 m2. Contour blasting is a technological method as it is carried out with the aim of obtaining the actual section of the mine working and also reducing the formation of cracks behind the contour part of the massif.
9127. METHODS FOR DETERMINING THE PROPERTIES OF ROCKS 299.19 KB
Taking into account the previously stated ideas about the hierarchical block structure of rocks and massifs and two fundamentally possible ways of determining the various characteristics of the integral and differential, let us consider in more detail the principles of determining individual properties. Thus, to determine the integral density characteristics of the massif represented by various petrographic varieties of rocks and various types of structural inhomogeneities, in principle, it is sufficient to determine these ...
1671. Mechanical properties and strength passport of rocks 1.11 MB
The essence of the new theory of strength. Determination of the parameters of the passport of strength. The tasks of the first section: to carry out simulation laboratory tests of rocks on a computer and determine their mechanical properties, ultimate strength, elastic modulus and Poisson's ratio.
2554. MOVEMENT OF ROCKS DURING UNDERGROUND DEVELOPMENT 384.33 KB
Mining operations violate the natural state of rock massifs, rocks, as a result of which the latter go out of balance, deform and move. Typically, these processes cover the entire thickness of the massif, including the surface. Rocks on the earth's surface also undergo deformation and displacement.
9130. NATURAL STRESS FIELD OF ROCK MASS 150.18 KB
Rocks as objects of study in geomechanics have one very significant feature in comparison with the objects considered in mechanics in general or in mechanics of deformable solids in particular. Tectonic stress fields are currently associated with the first of these types of movements. The data of direct measurements and observations in our country and abroad indicate the confinement of high horizontal stresses to the zones of tectonic uplifts of the earth's crust ...
9113. METHODS OF PROTECTION OF OBJECTS AND STRUCTURES IN THE AREA OF INFLUENCE OF MINING OPERATIONS 66.14 KB
To protect objects and structures from the harmful effects of underground mining and prevent water breakthroughs into mine workings, various protection measures are used, which can be conditionally divided into four groups: preventive mining engineering constructive complex. Preventive measures have the main purpose of preventing or reducing the harmful effects of mining.They should be carried out both during the period of drawing up projects for the development of deposits and ...
12930. RESEARCH OF MINERALS WITH THE HELP OF A POLARIZING MICROSCOPE. PETROGRAPHIC DESCRIPTION OF ROCKS 428.44 KB
The principle of operation of a polarizing microscope. Determination of refractive indices of minerals at parallel nicols. Study of the optical properties of minerals with crossed nicols. Study of other signs of minerals using a polarizing microscope.

For open mining exploration workings, substantiate the method of driving, the equipment used and, in accordance with the angle of repose of rocks, select and justify the shape and size of the cross-section, taking into account the design depth of development.

For underground mining and exploration workings, substantiate the method of driving and the corresponding mining equipment, select and justify the shape and dimensions of the cross-section of the workings in the open.

Depending on the physical and mechanical properties of rocks, as well as on the basis of the dimensions of transport and technological equipment (electric locomotives, trolleys, loading machines), taking into account the dimensions of the gaps provided for by the safety rules (PB) during exploration, the dimensions of the cross-section of mine workings in the light are determined ... The dimensions of the workings in the sinking are determined taking into account the thickness of the lining and ties, as well as the height of the track device (ballast, sleepers, rails).

Mine workings can be carried out with or without fastening. Wood, concrete, reinforced concrete, metal and other materials are used as fasteners. Sectional shape can be: rectangular, trapezoidal, arched, round, elliptical.

Horizontal and inclined exploration workings have, as a rule, a short service life, therefore, the main type of support is wood, the section shape is trapezoidal. When driving without fastening, the shape of the section is rectangular-vaulted.

For a trapezoidal section of a mine working with rail transport ( fig. one) it is recommended to calculate the cross-sectional area of \u200b\u200bthe mine in the following sequence.

The dimensions (width and height) of the used electric locomotive or trolley (for manual hauling) determine the width of a single-track working in the clear at the level of the edge of the rolling stock:

B \u003d m + A + n`

and the width of the double-track working:

B \u003d m + 2A + p + n`

m - the size of the gap at the edge of the rolling stock, mm(taken equal to 200 - 250 mm);

p - the gap between the compositions, mm (200mm);

n`- the size of the passage for people at the edge of the rolling stock, mm:

n` \u003d n + * ctg ;

n- the size of the passage at a height of 1800 mm from the level of the ballast layer, equal to at least 700 mm;

h -the height of the electric locomotive (trolley) from the rail head, mm;

h a- the height of the track superstructure from the ballast layer to the rail head, equal to 160 mm;

83 0 - the angle of inclination of the racks, adopted by GOST 22940-85 for exploration workings.

Working height from the rail head to the top in the case of using contact electric locomotives (up to the settlement of the support):

h 1 \u003d h kn. + 200 + 100,

h kn.- suspension height of the contact wire (not less than 1800 mm);

200mm - the gap between the contact wire and the support;

100mm- the amount of possible settlement of the lining under the influence of rock pressure.

With other types of transport, the height h 1determined by the graphical construction, taking into account the gap Cbetween the transport equipment and the ventilation pipeline: when transporting battery electric locomotives 250 mm, with manual haulage - 200 mm.

When transporting with a battery electric locomotive:

h 1 \u003d h + d t + 250 + 100,

where h - electric locomotive height, mm;

d t- diameter of the ventilation pipe, mm.

Height h 1in general, should not be less than the height of the loader with the bucket raised (for PPN-1s, this height is 2250 mm) minus the height of the ballast layer, i.e. h 1 2250 mm.

Opening width across the ballast layer:

l 2 \u003d B + 2 (h + h a) * ctg ;

Opening width across the roof:

l 1 \u003d B - 2 (h 1 - h) * ctg ;

Working height from the ballast layer to the support after settlement:

h 2 \u003d h 1 + h a;

Cross-sectional area of \u200b\u200bopenings after settlement:

S sv \u003d 0.5 (l 1 + l 2) * h 2;

Rough working width along the roof (when fastening in staggered directions with tightening the sides):

l 3 \u003d l 1 + 2d,

where d -support post diameter (not less than 160 mm).

Working width on the soil in the rough when fastening in staggered direction with tightening the sides:

l 4 \u003d B + ,

where h in= 320mm- height from the working soil to the rail head:

h c \u003d h a + h b,

where h b -ballast height.

Working height from soil to support (before settlement):

h 3 `\u003d h 3 + 100,

where ... h 3- the height of the excavation from the soil to the upper stand (after precipitation).

Rough working height before settlement in the presence of tightening:

h 4 `\u003d h 3` + d + 50,

where d - diameter of the fastening timber, mm;

50mm - tightening thickness.

Working height after settlement:

h 4 \u003d h 4 `- 100

Cross-sectional area of \u200b\u200bthe working in the rough before settlement:

S 4 \u003d 0.5 (l 3 + l 4) * h 4 `

Vertical draft equal to 100 mm, allowed only with wooden lining.

In the workings, the laying of wooden sleepers and the laying of the track from rails are used P24 for trolleys up to 2 m 3... When carrying out exploratory workings, trolleys are used VO-0.8; VG-0.7and VG-1,2 with a capacity of 0.8, respectively; 0.7; 1,2 m... When manually rolling with trolleys VO-0.8and VG-0.7, as well as AK-2u electric locomotives use rails P18... The sleepers are laid in a ballast layer with a thickness of 160 mmby immersing them in 2/3 of its thickness.

With a rectangular-vaulted shape, the height of the working in the clear is made up of the wall height from the level of the ballast layer and from the height of the vault ( fig. 2).

Rough working height H is defined as the clear height plus the thickness of the lining in the vault with monolithic concrete lining or plus 50 mm with sprayed concrete, anchor (rod) and combined support. The height of the wall from the level of the rail head to the heel of the arch h 1 during transportation by battery electric locomotives, it is determined depending on the height of the electric locomotive. The height of the workings during transportation by contact electric locomotives must satisfy the conditions under which the minimum clearances are provided between the electric locomotive (trolley) and the support, as well as between the pantograph and the support.

The height of the vertical wall from the tapa level to the heel of the arch h 2 \u003d 1800mm... The height of the vault h 0 take depending on the coefficient of rock hardness on the scale of M.M. Protodyakonov.

For monolithic concrete lining with a strength coefficient f =3:9, h 0 \u003d B / 3.

For sprayed concrete and roof bolting and in unsupported workings f 12 , h 0 \u003d B / 3, and at f 12, h 0 \u003d B / 4.

The curve of a three-center (box) vault is formed by three arcs: axial - R and two side ones - r... The radii of the vault depending on its height:

Arch height h 0 B / 3 B / 4
Axial arc radius R 0,692 0,905
Side arc radius r 0,262 0,173

Working width design B 1 with concrete lining, it consists of the width of the working in the clear and doubled the thickness of the lining, and in the case of sprayed concrete, anchor and combined lining, it consists of the width of the working in the clear plus 100 mm.

Single-track clear width:

B \u003d m + A + n

Open double-track working width:

B \u003d m + 2A + p + n,

where n \u003d700mm; p \u003d200mm.

Height of the vertical wall of the mine working from the rail head:

h 1 \u003d h 2 - h a \u003d 1800 - 160 \u003d 1640mm.

Rough working width with sprayed concrete and roof bolting:

B 1 \u003d B +2 \u003d B + 100,

where = 50mm - the thickness of the lining, taken in the calculation.

Cross-sectional area of \u200b\u200bthe working in the clear at the height of the arch h 0 \u003d B / 3:

S St. \u003d B (h 2 + 0.26B),

at h 0 \u003d B / 4: S sv \u003d B (h 2 + 0.175B),

where h 2 \u003d1800mm -the height of the vertical wall from the level of the ladder (ballast layer).

Height of the wall from the working soil:

h 3 \u003d h 2 + h b \u003d h 1 + h B.

Light output parameter at h 0 \u003d B / 3:

P B \u003d 2h 2 + 2.33B,

at h 0 \u003d B / 4: . P B \u003d 2h 2 + 2219B

The cross-sectional area of \u200b\u200bthe working out in the rough with sprayed concrete, anchor, combined support with h 0 \u003d B / 3:

S h. \u003d B 1 (h 3 + 0.26B 1),

at h 0 \u003d B / 4: S h \u003d B 1 (h 3 + 0.175B 1).

After determining the cross-sectional area, we take GOST 22940-85 the nearest standard section and write down its dimensions for further calculations. According to this standard, only the cross-sectional area of \u200b\u200bthe working in the clear is determined, and the cross-sectional area is roughly set depending on the adopted cross-sectional shape, type and thickness of the support according to the above formulas.

In the table 1 shows the typical cross-sections and basic equipment adopted for calculating the cross-section in the clear, as well as the dimensions of the basic vehicles.

Pits by depth are conventionally divided into shallow (up to 5 m), medium (5 - 10) and deep (up to 40 m). The depth of the pits depends on the stage of exploration and geological conditions. Depending on the physical and mechanical properties of the rocks, the method of penetration and the structure of the support, the pits are round and rectangular. With increasing pit depth, the clear cross-sectional area increases. Pits up to 10 m usually have one compartment, and with a depth of up to 20 m can be with two branches. Typical sections ( GOST 41-02-206-81), it is planned to drill pits with a clear cross-sectional area from 0.8 to 4 m 3 and geometrical dimensions (Table 2).

For adits and other underground mine workings, the following concepts are distinguished: cross-sectional area "in the rough" - without fastening; "In the light" - fixed development; "In sinking" - taking into account the inaccuracies of breaking the contours of the mine working, about 10% more than the section "in the rough". When driving, they adhere to the standard dimensions of the working in its cross-section, which is given either the shape of a trapezoid when using wooden lining or vaulted rectangular with concrete lining

The cross-sectional area "roughly" is calculated taking into account the diameter of the support elements, the width of the gaps between the support and the walls of the working. The cross-section is also selected based on the use of the support, the height of the working, the clearances between the support and the side rocks, the height and width of the hauling equipment, the width of the free passage, the height of the ballast layer. To calculate the width of the roadway along the roof and bottom and the cross-sectional area, allowable gaps between the walls, roof of the roadway and haulage equipment are taken into account, which are set on the basis of safety requirements and are given in the reference literature.

All horizontal mine workings are passed with some rise (0.002-0.008) to remove water from the workings by gravity.

A drift is a horizontal working that does not have a direct exit to the earth's surface, traversed along the strike of the bodies of minerals when they are inclined, and when the body is horizontal, in any direction along the length of the deposit.

Crosscut is a horizontal excavation that does not have a direct exit to the earth's surface, passing along the enclosing rocks or along the body of a mineral at an angle to their strike, most often across the strike.

Ort is traversed by the thickness of the mineral and does not go beyond its limits.

The dissection passes from another mine at any angle to the body of minerals, it can go beyond it. The length is usually short and does not exceed 20-30m.

Vertical workings.

A pit is a vertical excavation of a square, rectangular or circular cross-section (pits of a circular cross-section are called pipes), which has a direct exit to the earth's surface. Horizontal workings often pass from the pits: openings, crosscut holes, drifts.

It has typical clear dimensions and most often has a rectangular cross-sectional shape (Fig. 5, 6; Table 2). The cross-sectional area of \u200b\u200bthe pit generally depends on its depth. Pits with a cross section of 0.8 and 0.9 m2 are driven to a depth of 20 m, pits with a cross section of 1.3 m2 are driven to a depth of 30 m, 3.2 m2 are provided to pass to a depth of 40 m. depending on the thickness of the support. The actual cross-sectional area in the penetration is slightly larger. An increase in the area of \u200b\u200b1.04-1.12 times is allowed.

Driving unit, as a rule, consists of three people: two on the surface, one in the pit, with a cross-sectional area of \u200b\u200bmore than 2 m2, two tunnellers can work at the bottom.

The mine shaft has a larger section than the pits and a greater depth. The cross-sectional shape is usually square, ranging in size from 4-6 to 10-16 m2 (depending on the depth, scope of work and deadlines). Has access to the daytime surface; In some cases, the shaft is passed from horizontal underground workings, for example from adits, and is called "blind".

Gesenk, in contrast to a mine shaft, does not have a direct exit to the day surface; it serves to lower cargo and people from the upper to the lower horizons.

Inclined workings.

The slope is traversed along the fall of the mineral layer. When mining a mineral, it is usually used to lift loads from the lower horizon to the upper one.

Bremsberg is also traversed along the fall of the mineral, but unlike the slope, it is used to lower cargo and people from the lower to the upper horizon.

An uprising is a mine that has no outlet to the day surface and runs from the bottom up at any angle.


2. Methods and means of conducting tunneling works

2.1. Mining characteristics and classification of rocks

Physical and mechanical properties of rocks are the main factors that determine the choice of equipment and mining technology. The most important of these properties are strength and stability.

Fortress is a complex characteristic of rocks that characterizes their resistance to fracture and depends on properties such as hardness, toughness, fracturing, and on the presence of interlayers and inclusions. The concept of a fortress was introduced by prof. MM Protodyakonov, who suggested using the strength factor f for its quantitative assessment. In the first approximation, the value of f is inversely proportional to the ultimate strength of the rock in compression compressed. Since the strength coefficient is related to the strength of the rocks, it can be calculated in the simplest case using the formula

where is the ultimate compressive strength of rocks, Pa, for many rocks it ranges from 5 to 200 MPa.

Rocks are classified according to their resistance to destruction from external forces by relative strength, specific work of destruction, drillability and explosiveness.

The classification of rocks by fortress was developed by MM Protodyakonov in 1926. According to this classification, all rocks are divided into 10 categories. The first category includes the breeds of the highest strength (f \u003d 20), the tenth category includes the weakest floating breeds (f \u003d 0.3),

The choice of the method of conducting explosive breaking of rocks from the massif is influenced by the explosiveness, which is understood as the resistance of the rock to destruction by explosion. Explosiveness is determined by the amount of a reference explosive required to destroy a rock with a volume of 1 m3 (an indicator of the specific consumption of explosive). To determine the specific consumption of explosives (kg / m3) in relation to specific rocks, different classifications of rocks by explosiveness are used, for example, the Unified classification of rocks by drillability and explosiveness of prof. A.F.Sukhanova.

The drillability of a rock characterizes its ability to resist the penetration of a drilling tool into it and the intensity of the formation of a hole or borehole in the rock under the action of the forces arising from drilling. The drillability of the rock is characterized by the drilling speed (mm / min), less often - by the duration of drilling 1 m of the hole (min / m).

A unified classification of rocks by drillability was developed by the Central Bureau of Industrial Labor Standards for the standardization of mining exploration. Drillability is the resistance of the rock to the destructive action of the tool while drilling.

The main criterion for assigning rocks to one or another category in terms of drillability is the machine time of drilling 1 m of a hole under standard conditions. In this classification, rocks are divided into 20 categories, and according to drillability they are classified only within IV-XX categories. It is planned to develop rocks of I-III categories with jackhammers.

Other classifications have been developed to calculate the norms and various consumption indicators in relation to individual production processes (for example, the Unified Classification of Rocks by Drillability and Explosiveness, which is based on the drilling rate and specific consumption of explosives).

Stability of rocks is their ability to maintain balance when exposed. The stability of rocks depends on their structure and physical and mechanical properties, the magnitude of the stresses arising in the rock mass. The stability of rocks is one of the main features for choosing underground mining systems, determining its parameters and methods of securing mine workings.

According to their stability, rocks are conventionally divided into five groups.

Very unstable rocks, which do not allow the roof and sides of the mine to be exposed. They include floating, free-flowing and loose rocks.

Unstable rocks, allowing some outcropping of the sides of the excavation, but requiring the erection of support after the excavation. These rocks include wet sands, poorly cemented gravel, watered or heavily destroyed rocks of medium strength.

Rocks of medium stability, allowing the exposure of the roof over a relatively large area, but requiring the setting of support for prolonged exposure. These are rather compacted soft rocks of medium strength, less often hard and fractured.

Resistant rocks allow the roof and sides to be exposed over a large area, maintenance is required only in certain places. They are soft, medium and hard rocks.

Very stable are allowed without maintaining outcrop over a large area and for a long time (tens of years). It is not required to strengthen the workings in such rocks.

Table 3

Unified classification of rocks by drillability with hammer drills and electric drills for standardizing mining operations

Name of breeds:

I 0.1 Dry, loose clay in dumps. Loess is loose and moist. Sand. Loose sandy loam. Peat and vegetation without roots.

II 0.3 Gravel. Light loam, loesslike. Peat and vegetation layer with roots or with a small admixture of small pebbles and rubble.

III 0.5 Pebbles ranging in size from 10 to 40 mm. Clay is soft, oily. Sandy-clayey soils. Dresva. Ice. The loam is heavy. Crushed stone of various sizes.

IV 0.8-1.0 Pebbles ranging in size from 41 to 100 mm. Shale, moraine clay. Pebble-gravel soils bound by clay. Clay-bound sandy-clayey soils. Sandy-clayey soils with the inclusion of pebbles, gravel and boulders. Fine and medium-grained salts. Heavy loam with an admixture of crushed stone. The coals are very soft.

V 1.2 Clay siltstones, weakly cemented. Mudstones are weak. Conglomerates of sedimentary rocks. Manganese oxide ores. Marl is clayey. Frozen rocks of the I-II category. Sandstones weakly cemented with sandy clay cement. The coals are soft. Small phosphorite nodules.

VI 1.6 Gypsum, porous. Dolomites affected by weathering. Iron ore is blue. Calcified limestones. Frozen rocks of III-V categories. Cretaceous rocks are soft. Marl is unchanged. The ores are ocher-clayey with the inclusion of brown iron ore nodules up to 50%. Pumice. Carbonaceous shales. Trepel. Medium hard coals with clearly defined bedding planes

The dimensions of the cross-section of horizontal mine workings in the light depend on its purpose and are determined based on the dimensions of the rolling stock and the equipment located in the mine, ensuring the passage of the required amount of air, the gaps between the protruding parts of the rolling stock and the support, provided for by the Safety Rules and the method of movement of people.

In our case, we are designing a horizontal vaulted excavation with roof bolting.

Rectangular-vaulted sections are used when driving workings without support or with the construction of lightweight support structures. The height of the vault in sections from 2 to 6.8 m 2 is?. working width.

The clear cross-sectional area is the area along the inner contour of the support installed in the working

Calculation of the section of the mine

Cutting width

b \u003d b c + 2c \u003d 0.95 + 2 0.3 \u003d 1.55m

where b c - scraper width, m;

c - the gap between the scraper and the side of the mine, m.

In a mine of the type under consideration, people are allowed to walk only when the scraper installation is inoperative. Thus, the clearance height is assumed to be minimal, i.e. 1.8 m.

Arch height

Side cutting height (up to the heel of the arch):

1.8 - minimum production height according to PB

According to the calculated cross-sectional area in the light, the nearest larger of the standard cross-sections from table is taken. 2 (Tutorial "Conducting horizontal exploration workings and chambers" Authors V.I.

A typical cross-section of the production of substations is accepted - 2.7

The main dimensions of the working section in the clear:

Working width, mm - b \u003d 1550 mm

Working height to the heel of the arch, mm - h b \u003d 1320 mm

Working height, mm - h \u003d 1850 mm

The radius of the axial arc of the arch, mm - R \u003d 1070 mm

The radius of the side arc of the arch, mm - r \u003d 410 mm

Cross-sectional area of \u200b\u200bthe working in the clear, m 2 - S sv \u003d 2.7 m 2.

For workings with roof bolting:

where is the height of the working on the side, taking into account the exit of the anchors along the roof into the working by the value d \u003d 0.05 m.

Calculation of the strong dimensions of the lining, drawing up the fastening passport

Due to the small section of the mine, short service life, mining and geological conditions and available materials, we use metal expansion bolting AR-1

All calculations of the strength of anchoring in the borehole of the roof bolting were made according to the formulas from the reference book "Theory and practice of using roof bolting" Author A.P. Shirokov. Moscow "Nedra" 1981

c - angle of friction of rocks, 30 degrees

D - spacer sleeve diameter, 32cm

h - height of the spacer sleeve, 30cm

y s is the ultimate compressive strength of the rock

b - half the angle of a symmetrical wedge, 2 degrees

p 1 - angle of friction of steel on steel, 0.2 degrees

The required length of the anchor L and in the roof and the height of the possible fallout of the working rocks is found from the expressions:

L a \u003d b + L 2 + L 3 \u003d 0.04 + 0.35 + 0.05 \u003d 0.44m;

where L 2 - the value of the depth of the anchors beyond the contour of the possible fallout of rocks (taken equal to 0.35 m); L 3 - the length of the anchor protruding beyond the mine contour, L k \u003d 0.05 m; and n \u003d half-span of working in driving, m; h is the height of the excavation in the sinking, m.

Coefficient characterizing the stability of the sides of the mine;

Coefficient characterizing the slope of the creep prism in the sides of the working (taken according to Table 12.1. Theory and practice of using bolting. Author A.P. Shirokov. Moscow "Nedra" 1981);

c b - angle of internal friction (resistance) of rocks in the sides of the mine; К к - coefficient taking into account the decrease in the strength of rocks in the roof of the mine (taken according to Table 13.1);

f to - the coefficient of rock hardness in the roof of the workings;

K sr - the coefficient of concentration of compressive stresses on the contour of the mine, the value of which is taken from the table. 12.2;

d - the average specific weight of rock strata overlying the mine to the surface, MN / m 3; Н - working depth from the surface, m;

K b - coefficient taking into account the decrease in the strength of rocks in the sides of the working, the value of which is taken according to Table 12.1;

f b - coefficient of rock hardness according to M.M. Protodyakonov in the sides of the mine.

We accept the length of the anchor in the roof L k \u003d 0.5 m.

Due to the fact that w0, anchoring of the sides of the excavation is not performed.

Roof area supported by one anchor

where F to - the area of \u200b\u200bthe roof, supported by one anchor, m 2;

P k - the strength of the anchor in the hole drilled in the roof;

The safety factor, taking into account the uneven distribution of the load on the anchor and the possibility of surcharge from the overlying layers, is taken equal to 4.5;

b - the angle of inclination of the working, degree 0 0

Distance between anchor in a row:

where L n is the step of installing the anchors along the width of the working, m;

L y - the distance between the rows of anchors, m, taken 1.4 m

Number of anchors in a row

where L b \u003d 1.33b \u003d 1.331.55 \u003d 2.06m is the part of the working perimeter, which is to be anchored along the roof, m. Where b is the width of the working in the rough.

Accepts 2 anchors in a row.

Drawing up a fastening passport.

Clear cut width:

B \u003d B + 2m \u003d 950 + 3002 \u003d 1550mm.

Cutting arch height

h about \u003d b / 3 \u003d 1550/3 \u003d 520mm.

Rough cut height

h 2 \u003d h + h o + t \u003d 1320 + 520 + 50 \u003d 1890mm.

Rough cut wall height

h 3 \u003d h + t \u003d 1320 + 50 \u003d 1370mm.

Radius of the axial arc of the cutting arch

R \u003d 0.692b \u003d 0.6921550 × 1070mm.

Radius of the lateral arc of the cutting arch

r \u003d 0.692b \u003d 0.6921550 × 410mm.

Clear cross-sectional area:

S sv \u003d b (h + 0.26b) \u003d 1.55 (1.32 + 0.261.55)? 2.7m 2

Cross-sectional perimeter of the cut in the light:

P \u003d 2h + 1.33b \u003d 21.32 + 1.331.55 \u003d 4.7m.

Cross-sectional area of \u200b\u200bthe cut in the rough:

S hc \u003d b (h 3 + 0.26b) \u003d 1.55 (1.37 + 0.261.55) \u003d 2.75m 2.

Rough cut cross-sectional perimeter:

P \u003d 2h + 1.33b \u003d 21.37 + 1.331.55 \u003d 4.8m

Distance between anchors in a row: b 1 \u003d 1200mm.

Distance between rows of anchors: L \u003d 1.4 m

Depth of holes for anchors: l \u003d 500mm.

Diameter of boreholes for anchors: \u003d 43mm.

The maximum lag of anchor support from the bottom of the face is taken to be 3 m.

Scheme for calculating the dimensions of the cross-section when using scraper equipment in the development of a rectangular-vaulted section shape.