At stage 3700, a suspension passenger device is planned to be installed on the first level traffic lane. To meet the requirements for the installation of the nose and tail parts of the suspended passenger device, it is necessary to clean the sides, raise the roof. , and sprayed grout at the installation sites of the nose and tail. And chamber construction works, in order to ensure safety during the construction period, the following technical safety measures are formulated:
1. Construction overview
The location of the warheads is located 50 meters from the first level traffic lane at stage 3700 and the third level belt track; the specific position of the structure is subject to field calibration; the design uses an anchor Net support and an anchor support cable reinforcement Path.
Second, create an organization:
1. Create a leadership team in place:
Principal Project Responsible:
Project Safety Inspector: A full-time duty safety officer
Gas monitoring: gasman on duty
2. Responsibilities of the on-site leadership team:
Main Responsible Person: Fully responsible for safety management during the construction of sidewalls, roofing, spraying and chambers; Responsible for the overall organization and deployment of the side walls, roofing, spraying and chamber construction on site, as well as coordinating throughout the entire process. Manage construction work; at the same time be responsible for the placement and direction of tools and materials used during the construction of side brushes, roofing, spraying and chamber construction, and is the main responsible person during construction on site. command.
Site Safety Inspector: Responsible for safety supervision during the construction of the side, roof, sprayer and chamber.
Gas monitoring and monitoring officer: Responsible for gas monitoring and monitoring work at and near the working point, and is the first person in charge of on-site ventilation and gas management during the construction of side brushes, roofing, spraying and chamber design.
3. Hazard analysis and control measures during construction
(1) Hazard Analysis
During brushing, roofing and spraying, roof collapses, mechanical damage and insufficiently strong platform structure can occur, which can lead to a fall.
(2) Control measures
A: Control measures to prevent roof collapse
1. Operators should be familiar with the signs of roof collapse, such as slag, noise, cracks, crack expansion, layer separation, increased coal and waste rock leakage, roof impact thud, etc.
2. During the operation, the system of knocking and asking questions must be strictly observed. Before the start of each shift, the captain, team leader, technicianThe security officer and support technician must conduct a comprehensive and detailed inspection of the support, gas and other safety conditions in the workplace, and construction work can only be carried out after it has been confirmed that there are no potential safety hazards.
3. During the construction process, knocking on the roof should be carried out at all times. Personnel who knock on the roof should use long-handled tools to stand in a safe place and be under the supervision of a special person.
4.Strengthen control work at the workplace.If problems such as a sudden increase in pressure and failure of the support are detected, they must be maintained and eliminated in a timely manner by duty officers.If hidden dangers have not been eliminated, it is strictly forbidden to continue construction work.
5.After cleaning the curb and raising the roof, the curb should be strengthened by laying a metal mesh, steel ladders and steel anchors.At the same time, failed anchors should be repaired immediately. the preload of the anchor bolts must be at least 120 N.m.
6. Only one frame is allowed to be cleared each time, and the next frame is allowed to be processed only after full support of one frame is completed. When repairing the brush side, work should not stop until one machine is finished. Maintenance work must be carried out continuously, and in the case of an intermittent design, the gang must be closed each time before the end of the work.
7. During construction, special personnel must be assigned to monitor the construction site. If any abnormal situation is detected, the personnel must be immediately recalled and eliminated.
8.During construction, only one construction operation is allowed, and it is strictly forbidden to carry out construction work in two or more places at the same time.
9.Before starting construction, the anchor rods in the roof and brush sections must be re-tightened.
10.When stripping the side, construction should be carried out section by section from the whole part of the upper side to the unfinished part. It is strictly forbidden to build directly on the unfinished part in order to avoid large-scale parts of the side from falling off the roof.
11. When the open area of the roof after brushing is large, truss rods and truss wires must be used for reinforcement and support, and the distance between truss rods is 0.9m.
12. To clean the side, prepare a qualified solution spray material according to the requirements, so that the strength of the solution spray support can meet the requirements, so as to avoid the collapse of the roof of the roadway and the side of the part.
13. When spraying the solution, check the safety of the roof of the construction site. If there is live waste rock and charcoal on the roof, personnel should use tools with a longhandle to stand in a safe place and be under the supervision of a special person.
B: Mechanical Injury Controls
1.During construction, when using the MKS-50/1.7 pneumatic drilling rig, the operator must fasten the cuffs of his clothes to prevent entangling of the drill pipe.
2. When using a pneumatic hammer, it is necessary to frequently check the interface of the pipeline to prevent the U-card from falling off the pipeline and causing harm to people.
3. During construction, the conveyor belt must be blocked in the event of a power failure, and the operation can only be carried out after mutual confirmation, in order to prevent harm to people due to improper operation.
4. Before construction, responsibilities must be clear, the division of labor must be clear, and responsibility must be assigned to the person.
5. When using the shotcrete machine, thoroughly check its performance to prevent accidents such as injury caused by rotating parts, broken water pipes and material pipes during spraying, swinging when the air duct breaks, and injuries caused by careless spraying.
C: Controls for Poorly Performed Platforms
1. When erecting a work platform during construction, it must be installed safely and stably, and the overlap joints of the supported platforms must be securely fastened to prevent the platform from tipping over. After the platform is erected, the safety officer and the team leader must inspect and accept the supported platform, and only after the safety is confirmed, construction work can begin.
2. All platform operators must wear seat belts.
Fourth, construction technology:
(1) Pre-construction requirements and preparation
1. Before starting construction, the exploration department must pre-align the construction site of the 3700-stage first-class transportation route, and the construction team must strictly follow the calibrated position to complete brushing, roofing and chamber construction.
2. The general engineering bureau and the transportation department should study and implement measures for all construction personnel. Construction personnel should know the construction site and construction specifications, and often go deep into the site to check and control the construction quality. to ensure that the design is qualified once and rework is strictly prohibited.
3. Pneumatic jackhammers are used for side brush, roofing and chamber construction.
4. During construction, it is necessary to inspect the roadway support within 10 m from the construction site, while pipelines and belt racks in the roadway must be protectedsuch materials as sheathing, wooden boards, self-protection. protective covers are made to prevent damage during operation. Various objects.
5. Before starting construction, construction personnel must prepare construction tools in advance. Construction tools include a sledgehammer, mesh shears, roof support drilling rigs, ladders, boards, safety ropes, etc. Auxiliary materials include steel anchors and auxiliary tools, anchor wire equipment for machine supports, steel ladder, mesh, knitting wire, etc.
6. PS71 wet concrete mountain sprayer, sand (several squares), cement (several bags), quick setting compound (several bags), water pipes and connections, U-cards, etc. must be prepared before spraying. design Material.
(2) Construction method
1. Before starting construction work, the four-person identification system for the roof, the roof knocking system and the roof interrogation system, and the surrounding rock observation system must be strictly implemented. ● Conduct a comprehensive inspection and confirmation of the gas concentration and conditions, and allow other personnel to enter the construction site to perform operations only after confirming that the conditions for starting work are met.
2. Before starting construction, it is necessary to inspect and tighten the support within a radius of 10 m from the construction site; if low-quality anchor rods and anchor cables are found, they must be repaired in a timely manner. Due to the presence of anchor-sprayed support roadways in some areas, during construction, the mortar must first be sprayed, then the frame by frame, the original anchor trays, steel ladders, etc., should be dismantled, and finally, the mesh sheets should be cut frame behind the scenes with mesh scissors to facilitate expansion, overhead and camera construction.
3. How to build the installation site of the head:
(1) The left side is at a distance of 1 meter from the arch support, and the equipment chamber construction method is carried out using the pickaxe construction method Equipment chamber specification: width × height × depth = 3 meters × 3 meters × 2 meters.
(2) After installing the nose wheel (within 5 meters), the expansion depth of the left side is 1 meter, and the length is 15 meters as a monkey storage chamber; the depth of the right side expansion is 3 meters, 10 meters long as the installation position of the draw frame head, and then expands forward 5 meters, with a depth of 1 meter as the machine head motor and reducer service chamber.
4. The way to build the installation location of the tail:
(1) Near stage 3700 secondary traffic lane, lateral distance 3708 (lower) face wind bridgeAt 2 meters height methodThe construction of the counterweight chamber is carried out using pneumatic grips. The specification of the counterweight chamber is: width × height × depth = 1.5 meters × 3 meters × 1.5 meters.
(2) Use the warehouse of the original ventilation crew to turn it into a storage room for monkey poles.
5. Coal loading (rock) and transportation method:
Coal at the worksite is manually cleaned up to the first level conveyor belt of the 3700th stage for external transport.
6. When cleaning and supporting the side, the sequence of support should be followed: first throw, then maintain, first rise, then lower.
7. Once the roof has been raised and the side has been brushed, the exposed, failed tie rods must be cut away using tools such as hacksaws before the anchor mesh can be supported.
8. After raising the roof and cleaning the sides, spray.
(4) Requirements for the installation and operation of the operating platform
1. The construction site site is erected with steel pipes, that is, two steel pipes 4 meters long are first fixed on the roadside with anchor chains and lifting rings, and then firmly fixed with steel cables and steel ladders on the roadside, and then laid on it. At the same time, use iron wire to fix the two ends of the wooden board to prevent personnel from stepping into the air during the operation.
2. Operators must wear seat belts when working on the platform to prevent people from stepping on the air.
(5) Support design requirements
1. After the upper coal wall has been properly treated, use steel tie rods with metal mesh and steel ladders for support. Among them, a steel anchor with non-longitudinal ribbed steel anchor rod type MSGLW-335/20×2000, length 2000 mm (±10 mm), tensile strength ≥ 490 MPa, yield strength ≥ 335 MPa. , and the elongation is ≥ 15%.; The bearing capacity of the thread at the end of the rod body is ≥ 105 kN. The steel bar ladder at the top is supported by a steel ladder of appropriate length. The metal mesh is made of 10# iron wire, the size of the mesh used is 1200×10000mm, the mesh size is 50×50mm, the overlap with the top mesh is at least 15cm, and the guarantee is the overlap length and strength meet the requirements.
2. Anchoring method: extended resin anchoring, MSCKb2335 (one roll) and MSK2360 (one roll) resin anchoring agent is used for each roadway anchor rod, one roll is super fast and the other is fast. The anchoring length of the anchor rod is 0.9 m, and the pre-tightening torque of the installation of the steel anchor rod is at least 120 Nm.
3. The location of the anchor bolts on the roof: the pitch between the anchor bolts is 900 × 900 mm, the angle of installation of the anchor bolts on the roof at the curb is up tothe horns are 10° from the plumb line, the rest are perpendicular to the roof. .
Arrangement of anchors on the roadside: the pitch between the rows of anchors is 800 × 900 mm, the angle of installation of anchors on the side of the roof and the bottom plate is 10 ° from the horizontal line, and the rest are vertical towards the side of the road shoulder.
Anchor cables layout: the equipment chamber and the counterweight chamber support the anchor cables of the lock, and the equipment chamber supports 3 anchor cables, one of which is located in the middle of the roof, and the other two are located on both sides of the roof, at a distance of 1600 mm. The distance between the two gangs is 900mm, and one counterweight chamber support is located in the middle of the roof, the roof anchor cables at the top are arranged in "2-1 -2-1" with a row spacing of 1.8 m. There are two rows of anchor cables for any adjacent , the first row is two anchor cables (located on both sides of the top plate at a distance of 1400 mm, and the distance between the two sides is 1400 mm), and the other row is one anchor cable (located at the top of the previous row of anchor cables in the middle position) ; anchor cable at a distance of 1 m from the brush is located in the form ", and the anchor cable is installed every 2.7 m; the anchor cable on the 3m side of the draw frame head has a 2-1-2-1 pattern, row spacing is 2.7m for any two adjacent rows. anchor cables, the first row - two anchor cables (located on both sides of the roof, distance 1000 mm, distance between two sides 1000 mm), the other row - anchor cable (located in the middle of the previous row of anchor cables); model of anchor cable installed in this working: SKP18-1/1860, and specification: φ17.8×8300 mm; each anchor cable is MSCKb2335 (two coils), MSK2360 (two coils) and two anchoring speed resin coils, the pre-tightening force during installation is not less than 100kN, not more than 120kN; the anchor cable tray is 300mm×300mm×16mm square steel plate, and its center hole diameter is 20mm; If the roof is broken during excavation, anchor lines can be added appropriately, the distance between supports can be reduced, or 21.8 mm diameter anchor lines can be used to reinforce the support.
4. After cleaning the sides and lifting the roof, the failed bolts should be re-hammered to ensure that the bolt preload is correct.
5. Roof anchor technology
Excavating and unloading coal→strike the roof to detect dangerous stones→connecting to the mains→installing a temporary support→drilling an anchor hole in the middle of the roof with an anchor drill and clearing the hole (facing the work site→by placing a medicine roller in the hole→ into the anchor surface) → support the end of the steel bar of the beam, put the base plate on the end and tighten the nut (just screw on 4-5 buckles) → use the head of the truss rodto stand the medicine roll and guide it to the bottom of the hole → pick up the truss rod drill and use it. seconds) → stop agitation but keep the rig thrust for the set time (typically 1 minute) → connect the anchor and anchor to the locating end of the rod → Turn the bolt to tighten the nut → Install other roof bolts.
6. Roadway anchor bolt construction technology:
Connect the metal mesh → install the steel bar beam → fix the position of the hole → drill the hole with the drilling rig → clean the hole → insert the medicine coil into the hole → use the head of the anchor rod to support the medicine coil and guide it to the bottom of the hole → connect with stirrer. Rig tail and anchor rod → turn the rig to stir the volume of the drug for the specified time (usually 15-30 seconds) → stop stirring and wait for the specified time (usually 1 minute) → tighten the nut with a wrench until it stops → install other assistants. Anchor.
7. Upper anchor cable technology:
Anchor cable construction technology:
Fix the position of the anchor wire hole → drill the hole with the wireline drill rig → clean the hole → put the drug roll into the hole → support the resin drug roll with the anchor wire head and send it to the bottom of the hole → raise the drilling machine and use the agitator. Connect the drilling rig and the end of the anchor line → rotate the drilling rig to stir the resin roll for the specified time (generally 1 minute), then squeeze the anchor rod of the drilling rig and remove the agitator → wait 15 minutes → install the anchor installation base plate → tension with tensioning equipment Anchor cable with a pre-tensioning force of at least 100 kN, not more than 120 kN → install protective equipment against shots.
8. Construction spraying technology
(1), spray thickness
The bolt support can meet the strength requirements of the roadway support. Considering that the development and preparation of the roadway has a long service life, in order to prevent the coal roadway and shoulder from weathering, a layer of sprayed concrete has been added to the structure. The total thickness of the coating layer is 60 mm.
(2), material and strength of the sprayed layer
The ratio of cement:sand:crushed stone is 1:2.5:4.0. Ordinary Portland cement PO42.5#, medium-large sand, stone size 5-10mm, water-cement ratio 0.42-0.50, industrial water, accelerator 5-8% by weight of cement.
Shotcrete intensity C20.
(3), spray time
Sprayed concrete is divided into primary spraying and re-spraying. The thickness of the initial spraying is 30mm, the thickness of the re-spraying is 30mm. Clean the surface of the sprayed layer according to Feng Shuand before re-spraying. The concrete must be cured by water spray 2 hours after the final curing, and the curing time is 7 days.
(4), preparing the mixture
a. When mixing, all materials must be accurately weighed in accordance with the mixing proportions;
b. Use forced stirring for at least 90 seconds;
(5), equipment in place
The machine is installed in a stable area of the surrounding rock to ensure a smooth transmission line; Before loading the material, test run the concrete spraying machine first: turn on the high pressure air and high pressure water, if the air pressure of the nozzle is normal, feng shui spray foggy, for example, if the air pressure of the nozzle is not enough, the outlet may be blocked If there is no air from the nozzle, the supply pipe may be blocked, if there is a malfunction, it should be repaired in time, and the spraying operation can only be carried out after the normal operation of the sprayer.
(6), shotcrete key points
a. Before spraying support, protective measures must be taken for various pipelines, electromechanical equipment, conveyor belts and other objects within the spray range to prevent spray damage to various objects.
b. Before spraying, use high pressure air or high pressure water to clean the stone surface, and wash off the dust and nitrate debris attached to the stone surface to ensure that the concrete and stone surface adhere strongly; If you use high pressure water to clean the rock surface, this will cause only high pressure air (depending on geological conditions) to be used when softening to clean debris on the rock surface.
c. Strictly control the specified amount of accelerator and add it evenly;
d. The working air pressure in the jet is usually maintained at 0.2–0.4 MPa;
d. The sprayer strictly controls the water-cement ratio so that the surface of the sprayed layer is even and smooth, without dry spots or slipping and spreading;
f, nozzleThe direction of the nozzle should be perpendicular to the surface of the sprayed rock, and the distance between the nozzle and the surface of the sprayed rock should be within 0.6~1.0 meters;
g. The moving track of the nozzle must be adjusted according to local conditions. Alternate horizontal stripes, vertical stripes, circles, etc. should be used. The travel speed should be slow so that the concrete can be "folded" and removed after a certain thickness, and then block by block expands the spray range. ;
h, injection sequence is usually used first down and then up;
i, spraying thickness on both sides 6㎝;
j. If the unevenness is uneven,the undercut should be treated evenly first and then sprayed in the normal way to reduce rebound;
k. When there is a steel mesh, it is desirable to make the nozzle close to the steel rod, and the spray angle can also be properly shifted, and the shotcrete must cover the steel rod;
l. If there is a steel frame, the gap between the steel frame and the surrounding stone must be filled with spatter. Shotcrete should cover the steel frame and be sprayed upward on both sides.
n. After spraying or intermittently, the nozzle should be placed in a low place. After one shift, the nozzle should be disassembled, the water ring should be taken out, rinsed with water, the water eye should be scooped out and used in the next shift. After spraying, spray equipment should be cleaned and maintained to ensure that the equipment is in good condition.
(7), shotcrete technological parameters:
a. Working wind pressure: typically 0.2~0.4MPa;
b. Spray angle and spray distance
When the injection beam is perpendicular to the surface to be sprayed, the amount of bounce is minimal;
The distance between the nozzle and the surface to be treated should usually be 0.6-1.0 m;
c. Shotcrete thickness at one time: generally two sides 3㎝;
d. W/C Ratio: The sprayer should control the W/C ratio at 0.42-0.50 to ensure that the spray coat is even and smooth, with no dry patches or sagging and spreading;
d, interval between two injections:
The time interval of spraying two layers of concrete is too short, and it will crack and fall due to the insufficient strength of the previous layer of concrete. If the interval is too long, it will affect the construction efficiency. A more reasonable interval is the final setting of the previous layer of concrete and reaching a certain intensity before re-spraying, i.e. re-spraying is 50 m behind the original spraying distance;
e. Curing (dry place): The sprayed concrete must be cured due to the different drying conditions inside and outside the sprayed concrete. It is specified that curing should start two hours after the final setting of the sprayed concrete, and the curing should be at least 7 days;
p>g. Water pressure: nozzle water pressure adjustable 0.15~0.2MPa;
h. Accelerator: Master the indicated dosage and add it evenly.
（8）、Problems to pay attention to
①Rational use of the reactive machine
When starting the jet machine, it must supply air before turning on the machine, and the material must be supplied after the machine is working normally, and the material must be supplied evenly and continuously; Wind; after stopping the spraying operation, the accumulated material in the sprayer and the supply pipe should be cleaned in time to avoid agglomeration of the mixture and blockage of the pipe.
②Clogged supply pipe problem
Common causes of clogged pipes are as follows:
a. Stones, hard blocks of cement or other small particles whose particle sizes exceed the specified size are mixed into the mixture;
b. Incorrect operation procedure, such as turning on the engine before air is supplied, or the moisture content of the sand is too high, and the operating valve is displaced, causing a large amount of high pressure air to leak out. failure, which will lead to a sharp drop in air pressure in the working room, as well as clogging of the supply pipe;
c. In case of blockage, immediately turn off the engine, then turn off the air source, straighten the hose, and then tap with a hand hammer to find the blockage, and increase the air pressure to 0.3-0.4 MPa. , and keep tapping the locked part at the same time to make it unlock and unlock; When removing the blocked pipe, it should be noted that no one is allowed to stand in front of the nozzle to avoid injury accidents.
③Ricochet problem
Various factors affecting the rebound speed: mixture ratio, water-cement ratio, sand moisture, working wind pressure, water pressure, spray distance, spray angle, working method and craftsmanship, etc.; for different factors, take appropriate measures to reduce the rebound speed; under normal conditions, the rebound speed is controlled at 25% at the top and 15% at the side wall.
④Dust problem
a. Control the moisture content of sand and gravel: when the moisture content is controlled at 5~7%, the dust concentration during operation can be controlled below 15mg/m3;
b. Improve ventilation;
c. Extend the material pipe: Connect a 0.5-1m long pipe between the water ring of the nozzle and the outlet, so that the dry material and water go through a completely wet and mixed process, which can help reduce dust and improve the quality of concrete more favorable.
d. Strictly control the operating wind pressure: the wind pressure is too large, the feed rate is too high, it is not easy to evenly add water to the nozzle, and the wind pressure is too large, not only to increase the amount of rebound, but also to increase the concentration of dust.
⑤Occupational health and safety:
Be careful not to point the nozzle at people during construction, so as not to harm people when spraying. Before spraying, perform the necessary risk-removal operations, such as cleaning pumice and dangerous stones; The sprayer must be placed on a stable or leveled site.
Shotcrete personnel should wear dust masks, etc. Workers handling grout nozzles and pipes should wear safety goggles, laminated work clothing, and long-sleeved latex gloves.
(9), pavement quality standard according toafter spraying
Inspection elements
Design value
Basic Requirements
Spray layer thickness
60 mm
At least 90% of the cost of the design
Surface flatness
Smooth and smooth without edges or corners
The maximum unevenness within 1 m3 should not exceed 50 mm.
The sprayed concrete is made of C20 concrete and the thickness of the sprayed concrete is 60mm. The thickness of the shotcrete layer in the anchored sprayed concrete should be at least 90% of the design one, a group of inspection holes should be drilled on the site every 25 m, the number of observation holes in the group should be at least 3, evenly spaced. The strength of the shotcrete meets the design requirements, and the depth of the foundation must be at least 90% of the calculated one.
Fourth. Technical security measures
(1) Organizational technical measures
1. The operating site must be equipped with qualified operators to operate; the construction manager must have a clear division of labor in the operation process, distribute responsibilities between individuals and work closely. Violation of the rules is strictly prohibited.
2. Gas personnel must test the gas in the roadway before working at the workplace, and only the concentration of the gas is within the specified range before working.
3. The operation point must be equipped with a full-time safety officer who is responsible for safety supervision and construction site inspection to eliminate hidden hazards on the roof to ensure the safety of the work site.
4. The person in charge of the construction timely organizes and resolves relevant issues, and promptly eliminates various emergency situations that arise during the construction of the working point to ensure the smooth progress of all work.
5. Roofing should not be carried out in parallel with the transport of coal, and roofing should only be done after the conveyance of the tape has stopped.
6. Plant managers at all levels must conduct regular or irregular audits, apply appropriate technical safety measures, strictly adhere to the shift system and ensure operational safety.
(2) Technical safety measures for construction work
1. Before operation, it is necessary to carry out a comprehensive and detailed inspection of the top side and anchor wire of the operating point. If the bolts of the upper side and anchor wires are loose or the cables need to be repaired in time. The loosened anchor rod and anchor wire must be tightened twice to ensure the safety of the working point.
2. Strictly implement the "knocking on the roof", "four-person joint assessment system on the roof", "surrounding rocks observation system", and confirmation of safety on site before shift; for support, as soon as an anomaly is detected, before carrying out aboutoperation, effective action must be taken.
3. During the construction of the roof, there must be a special person who must knock on the roof at the construction site and its surroundings at any time. If any abnormal situation is detected, the personnel must be immediately evacuated and eliminated. Operation. When tapping from above, you must use a long-handled tool to stand in a safe place and be under the supervision of a special person.
4. Pipelines, racks and other objects must be protected prior to construction to prevent damage.
5. If during construction the winch raises and lowers material, the operation must be stopped and evacuated to a safe place. And a dedicated person is responsible for confirming on site that the winch is no longer working before a second operation can be performed.
6. During the construction process, the facilities and equipment used must be properly managed to prevent their loss.
7. The truss rod must be drilled at the specified angle and must not be drilled into a bed or crack.
8. In the process of operation, it is necessary to strengthen the management on site. It is necessary to constantly monitor the safety of the support. If any abnormal situation is detected, all personnel must be recalled and brought to the attention of the head of the mine, the control room and the relevant departments. Safe and reliable measures can be formulated before contacting. Any personnel are strictly prohibited work with risk.
(3) Technical precautions for spraying
1. First, check and eliminate unsafe factors in the workplace, knock from the side and ask from above, use long-handled tools to remove floating waste rock and dangerous stones, and start work after confirming safety.
2. Before spraying, it is necessary to carry out a comprehensive check of the spraying equipment, pipelines for supplying air, water and electricity, and also pay attention to checking the presence of concrete agglomerates, large stones and other rubbish in the sprayer tank; Is there too much cement on the slab, is there cement slurry in the outlet of the shotcrete machine, does it fit well with the sealing rubber gasket, is there any adhesion or blockage in the outlet, and are the inlet and outlet valves unlocked, in whether the pressure gauge, engine and transmission parts are normal, whether the control handle and switch button are sensitive, whether the sealing parts are sealed, whether there is oil in the gearbox and each bearing, and check whether the transmission parts are flexible and reliable due to idle air pressure, there are whether there is air leakage, and adjust the air pressure pipeline.
3. Check if the mixture is mixed evenly, if the ratio is correct and if there are no foreign matter.
4. Before napBy spraying, it is necessary to find out the degree of convexity and concavity of the sprayed part, as well as to ensure the characteristics of the sprayed roadway, the thickness and evenness of the sprayed layer. Before spraying the solution, flush the roadside with pressurized water, which should be rinsed on the site and sprayed on the site.
5. At the beginning of spraying, the material should be fed continuously and evenly so that the material is filled without overflow, and at the same time the accelerator is evenly mixed into the hopper in proportion; To reduce flying dust, operators must also wear work protection equipment; when two people serve materials, they should pay attention to each other's shovel up and down and not hurt each other; The feeder should pay close attention to the operation of the shotcrete machine. If air leakage, gusty wind or abnormal engine noise is found, stop the machine immediately for inspection and treatment.
6. The sprayer must support the nozzle with one hand, adjust the water valve and direct the flow with the other hand. When spraying, all surfaces to be sprayed must be covered with a thin layer of concrete to cover the pre-sprayed surface. The spraying method can be circular spraying or linear spraying. When spraying circular spraying, make slow circular motions in a spiral and semicircle in the horizontal direction. The diameter of the circle is preferably 200-250mm. Perform repetitive motions in the horizontal direction. when the line is sprayed.
7. The sprayer must control the spray angle, spray distance, primary spray thickness, water-cement ratio, rebound rate, roadbed specification requirements, and spray according to the spray position and rock characteristics of the well roadway. The spraying procedure is to spray the wall first and then the arch from the bottom to the top, first spray half of the roadway, then rotate the nozzle to spray the other half of the roadway, and finally close the roof. As a rule, cracks and over-dredging areas are sprayed first, that is, depressions are filled first, and then a platform is found, and then sprayed in accordance with the operation described above.
8. The driver of the shotcrete machine must undergo special training, know the structure and principle of operation of the shotcrete machine, be able to eliminate general malfunctions and carry out daily maintenance and repair.
9. The spraying operation is carried out with the cooperation of 2 workers. The shooter holds the spray head to work, and the assistant observes the spraying situation and carries out security control.
10. During the spraying process, the sprayer and the deputy should cooperate closely. The deputy observes the spraying situation and quickly uses signals to indicate the spraying position and direction so that spraying can be completed. smoothly.
11. When starting and spraying, it is strictly forbidden to point the nozzle of the spray gun at people, no one is allowed to stand near the nozzle so that the sprayed material does not harm people, and it is strictly forbidden to put hands, heads or other objects into the sprayer.
12. During the injection process, in case of pipe blockage, wind power failure and other failures, the water valve must be closed immediately and the nozzle must be pointing down to prevent water from entering the injection pipe.
13. The sprayer must work in strict order. When work starts, supply wind and water first, and then supply power and supply material; Finally, turn off the water, stop the wind, and cover the gunning machine for a while.
14. If the pipe becomes clogged during operation, it should be removed in time. When dealing with clogged pipes, first straighten the hose and tap the pipe with a hand hammer to find the blockage; after detecting a blockage, increase the air pressure to 0.3-0.4 MPa and tap the pipe with a hammer to find the blockage. it's unlocked. If the nozzle is clogged, no other personnel are allowed to stand in front of or near the nozzle of the spray gun, in order to prevent sudden release of the jet or pipeline and injury to people. If during construction there is a sudden stop of wind, electricity or water, and work cannot continue, the mixture in the sprayer and pressure pipe should be cleaned in a timely manner.
15. When working with blocked pipes, the impact method is used to move the pipes with material. Employees are strictly prohibited from touching the loading port of the shotcrete machine with any part of their body to clear blockages.
16. After routine spraying work, it is necessary to remove the spray head and clean all the solution and materials inside and outside of the water ring and spray machine.
17. After each shift, it is necessary to sanitize the upper and lower 10 m of the working area, as well as neatly stack materials.
18. The shotcrete machine is installed on a special vehicle and parked on the track. The parking space must use the rail clamp and tripod to block the vehicle to ensure the safety of the vehicle.
19. Sprayed concrete support is carried out on the transport lane. Before the unloading crew is required to transport materials through the transport lane, a dedicated person must be assigned to notify spray operators to evacuate to safety before the transport operation can be completed. After the transportation is completed, the slurry spraying workers do the construction work again.
V. Measures to prevent natural disasters
During the construction of the face, the requirements for roof management must be strictly followed to this extent and unsafe hidden ops must be eliminated in a timely mannerdrowsiness; in the event of an accident at a construction site, all personnel at the scene of the accident are required to report to the dispatching command post, clearly explain the nature, time, place, situation and extent of possible damage to the accident, and take all effective measures to minimize the natural disaster and organize evacuation emergency avoidance route.
Help when falling from a roof, how to avoid an accident
Level 1 transport lane at Stage 3700→Level 3, Level 2 and Level 1 track (belt) lane→lower mine platform→main (auxiliary) shaft→surface
Other pending issues should be implemented in strict accordance with the "Coal Mine Safety Regulations" and "Basic Requirements and Evaluation Methods of the Coal Mine Production Standardization Management System".