Rock burst area roadway excavation-following synchronous blasting pre-pressure-relief and water bag dust falling method

Abstract

According to the rock burst area roadway excavation-following synchronous blasting pre-pressure-relief and water bag dust falling method, rock burst area roadway excavation-following blasting pre-pressure-relief is integrated into one working procedure, water bags are adopted for blocking and dust falling, and the specific steps and conditions include six points, namely rock drilling, charging and blasting of rock burst area roadway pre-pressure-relief blast holes and excavation blast holes are integrated into one working procedure; the pre-blasting pressure relief procedure before rock burst roadway tunneling is reduced, the time of ventilation, danger elimination and the like after pressure relief blast hole blasting is saved, the rock burst roadway tunneling construction process is shortened, and the purpose of improving the construction efficiency is achieved; the long-distance (2.6-3.8 m) water bag is adopted to block the pressure relief blast hole, after the pressure relief blast hole and the tunneling blast hole are detonated together, a large amount of water in the water bag can be rapidly combined with dust and blasting fume generated by tunneling blasting of a roadway, the dust and the blasting fume of the roadway can be effectively reduced, the air environment of the roadway is improved, the ventilation time is shortened, and the construction efficiency is improved; technical support is provided for rapid and safe construction of the rockburst roadway, and the method has the advantages that rockburst can be prevented, and dust and smoke hazards generated by roadway blasting tunneling can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of metal and non-metal underground mines, and particularly relates to a method for synchronous blasting pre-pressure relief and water bag dust reduction during roadway excavation in a rock burst area. Background Technique

[0002] When excavating a roadway by blasting in a rock burst area, rock burst phenomena are likely to occur on the roadway heading face, such as bursting and falling off, ejection, etc., endangering the safety of operating personnel; in addition, a large amount of dust and fumes are often generated during roadway blasting excavation, and it is necessary to ventilate for a long time before entering the roadway to continue the operation. Especially for the excavation of a long-distance blind roadway, the ventilation time is extremely long, affecting the construction efficiency of the roadway.

[0003] In the face of the harm of rock burst, an additional process - blasting pre-pressure relief - is often added before each roadway excavation, that is, first construct over-deep blasting relief holes on the heading face, and prevent rock burst by pre-blasting to relieve the pressure of the rock in the next excavation cycle area. After the blasting of the current roadway excavation, the formed roadway heading face is not likely to have rock burst; for the harm of roadway blasting dust and fumes, the ventilation time is often increased or a high-power local fan is used to improve it, or a small amount of water bags are used to block the blast holes at 20 - 30 cm from the hole mouth to reduce dust and fumes.

[0004] However, after adding an additional pre-blasting pressure relief process during roadway excavation, it is equivalent to performing two blasts and ventilations for each roadway excavation, increasing by about 2 - 3 hours, reducing the construction efficiency of roadway excavation; and using water bags to block the blast holes at 20 - 30 cm from the hole mouth to reduce dust and fumes often has a poor dust reduction and smoke removal effect due to the short length of the water bag blockage and its proximity to the hole mouth.

[0005] To solve the above problems, some people have successively disclosed: Patent CN 117005868 A "Water pressure-blasting coupling pre-splitting top cutting pressure relief device and its use method", the process flow of this method is to drill holes in stages (70° and 50° angles), install a combination of a hydraulic fracturing tube and a concentrated blasting tube, first hydraulic fracturing and then blasting, and then hydraulic fracturing for the second time, and expand the cracks by coupling water pressure and blasting, which can solve the problem of hard roof collapse, but because it is a static staged construction, the purpose is to focus on the top cutting, which is not possible because users are dynamic excavation pressure relief; Patent CN 117211802 A "A tunnel advance blasting pressure relief method", the process flow of this method is to determine the pressure relief area by advance drilling, blast in stages (slot holes, auxiliary holes, peripheral holes in order), emphasize micro-difference blasting, can optimize blasting parameters, and improve tunnel safety, but because it is advanced static pressure relief, the purpose is to optimize blasting parameters, which is not possible because users are dynamic excavation pressure relief; Patent CN 118327580 A "High stress area pressure relief method for excavation working face", the process flow of this method is to determine the stress concentration area through the cuttings method, construct coal seam blasting holes in a targeted manner, emphasize sealing and monitoring, the purpose is to improve accuracy, accurately locate high stress areas, reduce the risk of rock burst, and rely on the cuttings method for accurate positioning; Patent CN 118548055A "A three-dimensional directional blasting pressure relief method for rapid excavation of coal seams in mines", the process flow of this method is to adjust the borehole spacing (15m), lateral coal body blasting, combined with support and shock reduction measures, the purpose is to reduce the amount of impact control engineering, and can improve the efficiency of the excavation and anchoring machine; Patent CN 119373513 A "A pressure relief method for coal mine anchoring working face", the process flow of this method is to blast in three areas: the head, the side and the top, emphasizing multi-angle drilling and top breaking measures, which can resolve the stress concentration caused by rapid excavation, but because it is a multi-area phased construction, it involves top breaking measures, and its "synchronous blasting with excavation + water bag dust reduction" is synchronous blasting with excavation, without the need for regional construction, and with the addition of water bags for dust reduction, the function is more comprehensive; Patent CN 119507924A "Coal mine tunnel floor drum prevention and control method based on floor blasting pressure relief", the process flow of this method is to determine the floor blasting range through sliding body analysis, combined with grouting reinforcement, it can prevent floor drum deformation and optimize floor stability, but because it focuses on solving the floor drum problem, it involves floor sliding body analysis, which is floor management.

[0006] In summary, the present invention application (BS) "Pre-pressure relief by synchronous blasting with excavation + dust suppression by water bag" is different from the above patents in that:

[0007] Process differences: BS is centered on "simultaneous blasting with excavation and pre-decompression + water bag dust reduction", and the technical solution does not rely on the cuttings method, advance drilling or bottom plate sliding body analysis. The technical path is independent. The above patents are mostly staged, regional or static blasting, and the process sequence and construction methods are significantly different;

[0008] Functional extension: BS integrates the functions of pressure relief and dust reduction, making it more comprehensive. The above patents only focus on pressure relief or the treatment of specific scenarios;

[0009] In summary, BS has significant differences from the above patents in terms of process flow, target scenarios, and technical combinations, and no prior art that can undermine the present invention has been found.

[0010] Therefore, it is of great significance to develop a method for synchronous blasting pre-pressure relief and water bag dust reduction during roadway excavation in rock burst areas. Summary of the Invention

[0011] The task of the present invention is to overcome the deficiencies of the prior art and provide a method for synchronous blasting pre-pressure relief and water bag dust reduction during roadway excavation in rock burst areas, which can not only prevent rock bursts but also reduce the dust and fume hazards generated by roadway blasting excavation.

[0012] The innovation points of the present invention are as follows:

[0013] (1) Integrate the rock drilling, charging, and blasting of the pre-pressure relief holes and the excavation holes in the roadway of the rock burst area into one process, that is, reduce the pre-blasting pressure relief process before the excavation of the rock burst roadway, save the time for ventilation and risk removal after the blasting of the pressure relief holes, shorten the construction process of the rock burst roadway excavation, and achieve the purpose of improving construction efficiency;

[0014] (2) Use long-distance (2.6 - 3.8m) water bags to block the pressure relief holes. When the pressure relief holes and the excavation holes are detonated together, a large amount of water in the water bags can quickly combine with the dust and fumes generated by the roadway excavation blasting, effectively reducing the roadway dust and fumes, improving the roadway air environment, reducing the ventilation time, improving the construction efficiency, and providing technical support for the rapid and safe construction of the rock burst roadway.

[0015] The task of the present invention is completed through the following technical solutions:

[0016] A method for synchronous blasting pre-pressure relief and water bag dust reduction during roadway excavation in rock burst areas. Aiming at the problems of time-consuming pre-blasting pressure relief process equivalent to two blasts and ventilations required for each roadway excavation, low construction efficiency of roadway excavation, and poor dust and fume reduction effect during mine roadway excavation, the pre-pressure relief of roadway excavation blasting in rock burst areas is integrated into one process and water bags are used for dust reduction by blocking. The specific steps and conditions are as follows:

[0017] A. Drilling: First, construct the roadway excavation holes, and then construct several ultra-deep pressure relief holes at three positions between the excavation holes, about 1 / 3 roadway height, 1 / 2 roadway height, and 2 / 3 roadway height from the roadway floor;

[0018] B. Charging the excavation holes: Use a blasting rod to load the explosive cartridges into the excavation holes, place the detonator at the bottom of the hole, and seal the hole mouth with stemming;

[0019] C. Ultra - deep pressure - relief blast - hole charging: First, place the detonator at the bottom of the ultra - deep pressure - relief blast hole, load explosive cartridges at a position 1 - 2 m away from the hole bottom, and install a detonating cord for transmission that can ensure the complete detonation of the explosives. The remaining part of the pressure - relief blast hole is filled with water bags slightly smaller than the hole diameter for plugging.

[0020] D. Initiation: The pressure - relief blast holes do not change the original initiation sequence of the tunneling blast holes. The ultra - deep pressure - relief blast holes and the tunneling blast holes closest to them are set at the same section and initiated simultaneously.

[0021] E. Ventilation: After blasting, local fans are used for ventilation. After the ventilation effect meets the operating conditions, enter the roadway to carry out the next cycle of work. Integrate the pre - pressure - relief blasting and tunneling blasting of the rock - burst roadway into one process that can shorten the construction time and improve the construction efficiency. That is, first, construct tunneling blast holes and ultra - deep pressure - relief blast holes at the roadway face, carry out blast - hole charging, where only the ultra - deep part of the ultra - deep pressure - relief blast holes is loaded with explosives, and then fill the remaining part of the ultra - deep pressure - relief blast holes with water bags.

[0022] F. When the adjacent ultra - deep pressure - relief blast holes are initiated during the tunneling blast - hole blasting of the roadway, a loosening zone or fracture zone can be formed around the ultra - deep part of the ultra - deep pressure - relief blast holes after the blasting, reducing the integrity and stress state of the surrounding rock, thereby reducing the rock - burst risk and effectively alleviating the rock - burst hazard at the roadway face in the next tunneling cycle. At the same time, the water in the plugged water bags will be flushed out by the blasting, and it can also reduce the dust, blast fume hazard, ventilation time, and rock - burst risk and hazard generated by the roadway tunneling blasting, thus improving the underground air environment of the roadway blasting and tunneling and enhancing the construction efficiency of the rock - burst roadway.

[0023] Compared with the prior art, the present invention has the following advantages or effects:

[0024] Because the pre - pressure - relief blasting and tunneling blasting of the rock - burst roadway are integrated into one process, the construction time is shortened. At the same time, due to drilling and simultaneous blasting, one process is reduced, so the construction efficiency can be greatly improved. In addition, since a large number of water bags are filled in the pressure - relief blast holes to plug the holes and the pressure - relief blast holes and tunneling blast holes are initiated together, the water in the water bags can combine with the dust and blast fumes generated by the roadway tunneling blasting, so it can also improve the roadway air environment and reduce the ventilation time.

[0025] In summary, in view of the problems in the prior art such as the independence of the pre - pressure - relief blasting and tunneling blasting processes in the construction of rock - burst roadways, large amounts of dust and blast fumes in the roadway blasting and tunneling, multiple processes, long ventilation time, and low construction efficiency, the present invention: First, integrates the pressure - relief blast - hole blasting and tunneling blast - hole blasting of the rock - burst roadway into one process, shortening the process and improving the construction efficiency. Second, by filling a large number of water bags in the pressure - relief blast holes to plug the holes, after the pressure - relief blast holes and tunneling blast holes are initiated together, a large amount of water in the water bags can quickly combine with the dust and blast fumes generated by the roadway tunneling blasting, effectively reducing dust and removing smoke, improving the roadway air environment, reducing the ventilation time, and accelerating the tunneling cycle of the rock - burst roadway. Description of the Drawings

[0026] Figure 1 It is a front view schematic diagram of the arrangement of roadway driving blast holes and pressure relief blast holes for the method of simultaneous blasting pre-pressure relief and water bag dust reduction during roadway driving in a rock burst area proposed according to the present invention.

[0027] Figure 2 is Figure 1 The schematic diagram of the water bag plugging and charge connection of the pressure relief blast holes shown.

[0028] Each label in the drawings respectively represents:

[0029] 1. Rock 2. Roadway contour line 3. Driving blast hole 4. Ultra-deep pressure relief blast hole 5. Water bag 6. Explosive cartridge 7. Blasting cap leg wire 8. Blasting cap 9. Detonating cord

[0030] The present invention will be further described in detail below with reference to the drawings. Specific Embodiments

[0031] As shown in the attached Figures 1-2 For the method of simultaneous blasting pre-pressure relief and water bag dust reduction during roadway driving in a rock burst area, aiming at the problems of time-consuming for adding a pre-blasting pressure relief process equivalent to two blasts and ventilations for each roadway driving, low construction efficiency of roadway driving, and poor dust reduction and smoke removal effects during mine roadway driving, the rock burst area roadway driving blasting pre-pressure relief is integrated into one process and water bag plugging is used for dust reduction. The specific steps and conditions are as follows:

[0032] A. Drilling: First, construct the roadway driving blast holes (3), and then construct several ultra-deep pressure relief blast holes (4) at three places between the driving holes (3), about 1 / 3 of the roadway height, 1 / 2 of the roadway height, and 2 / 3 of the roadway height from the roadway floor;

[0033] B. Charging the driving blast holes: Use a blasting rod to load the explosive cartridges (6) into the driving blast holes (3), place the blasting caps (8) at the bottom of the holes, and plug the hole openings with stemming;

[0034] C. Charging the ultra-deep pressure relief blast holes: First, place the detonator at the bottom of the ultra-deep pressure relief blast hole (4) and load the explosive cartridge (6) at a distance of 1 - 2 m from the bottom of the hole, and there is a detonating cord (9) for ensuring the complete detonation of the explosive. The remaining part of the pressure relief blast hole (4) is filled with water bags (5) slightly smaller than the hole diameter to plug;

[0035] D. Initiation: The pressure relief blast holes (4) do not change the original initiation sequence of the driving blast holes (3). The ultra-deep pressure relief blast holes (4) are set at the same section as the driving blast hole (3) closest to it and are initiated simultaneously;

[0036] E. Ventilation: After blasting, local fans are used for ventilation. After the ventilation effect meets the operation conditions, the next cycle of work is carried out in the roadway. Integrating the pre-pressure relief blasting and tunneling blasting of the rockburst roadway into one process can shorten the construction time and improve construction efficiency. That is, first, the tunneling blast holes (3) and the ultra-deep pressure relief blast holes (4) are constructed at the roadway face, and the blast holes are charged. Only the ultra-deep part of the ultra-deep pressure relief blast hole (4) is filled, and then the remaining part of the ultra-deep pressure relief blast hole (4) is filled with water bags (5).

[0037] F. When the adjacent ultra-deep pressure relief blast hole (4) is detonated during the blasting of the roadway tunneling blast hole (3), after the ultra-deep pressure relief blast hole (4) blasts, a loosening zone or fracture zone can be formed around the ultra-deep part of the ultra-deep pressure relief blast hole (4), reducing the integrity and stress state of the surrounding rock (1), thereby reducing the rockburst risk and effectively alleviating the rockburst hazard at the roadway face in the next tunneling cycle. At the same time, the water in the blocked water bag (5) will be flushed out by the blasting, and it can also reduce the dust, fume hazard, ventilation time, rockburst risk and hazard generated by the roadway tunneling blasting, thereby improving the underground air environment of the roadway blasting tunneling and enhancing the construction efficiency of the rockburst roadway.

[0038] The method of the present invention can further be:

[0039] In the step A, the ultra-deep pressure relief blast hole (4) is 1 - 2 m deeper than the tunneling blast hole (3), and the diameter is about 42 mm.

[0040] In the step A, a total of 4 - 6 ultra-deep pressure relief blast holes (4) are constructed at three locations.

[0041] In the step B, the diameter of the tunneling blast hole (3) is 20 - 30 cm.

[0042] As described above, the present invention can be preferably realized. The above embodiments are only the best implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall all be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. Rock burst area roadway synchronous blasting pre-pressure relief and water bag dust reduction method during tunneling. Aiming at the problem that an additional pre-blasting pressure relief process equivalent to two blasts and ventilations for each roadway tunneling is required during roadway tunneling, which is time-consuming, has low roadway tunneling construction efficiency, and poor dust and smoke removal effects, it is characterized in that Integrate the roadway blasting pre-pressure relief in the rock burst area into one process and use water bags to block dust. The specific steps and conditions are as follows: A. Drilling: First, construct the roadway tunneling blast holes (3), and then construct several ultra-deep pressure relief blast holes (4) at three locations between the tunneling holes (3), about 1 / 3, 1 / 2, and 2 / 3 of the roadway height from the roadway floor. B. Charging the tunneling blast holes: Use a blasting rod to load the explosive cartridges (6) into the tunneling blast holes (3), place the detonator (8) at the bottom of the hole, and seal the hole mouth with stemming. C. Charging the ultra-deep pressure relief blast holes: First, place the detonator at the bottom of the ultra-deep pressure relief blast hole (4) and load the explosive cartridges (6) at a distance of 1 - 2 m from the bottom of the hole. Install a detonating cord (9) that can ensure the complete detonation of the explosive. The remaining part of the pressure relief blast hole (4) is filled with water bags (5) slightly smaller than the hole diameter to block. D. Initiation: The pressure relief blast holes (4) do not change the original initiation sequence of the tunneling blast holes (3). The ultra-deep pressure relief blast holes (4) are set to the same section as the nearest tunneling blast hole (3) and are initiated simultaneously. E. Ventilation: After blasting, local fans are used for ventilation. After the ventilation effect meets the operating conditions, enter the roadway to carry out the next cycle of work. Integrating the pre-pressure relief blasting and tunneling blasting of the rock burst roadway into one process can shorten the construction time and improve construction efficiency. That is, first construct the tunneling blast holes (3) and ultra-deep pressure relief blast holes (4) at the roadway heading face, and carry out hole charging. Only the ultra-deep part of the ultra-deep pressure relief blast hole (4) is filled, and then the remaining part of the ultra-deep pressure relief blast hole (4) is filled with water bags (5). F. When the roadway tunneling blast holes (3) are blasted, the adjacent ultra-deep pressure relief blast holes (4) are initiated. After the ultra-deep pressure relief blast holes (4) are blasted, a loosening zone or fracture zone can be formed around the ultra-deep part of the ultra-deep pressure relief blast holes (4), reducing the integrity and stress state of the surrounding rock (1), thereby reducing the rock burst risk and effectively alleviating the rock burst hazard at the roadway heading face in the next tunneling cycle. At the same time, the water in the sealed water bags (5) will be flushed out by the blast, and it can also reduce the dust, fume hazard, ventilation time, rock burst risk and hazard generated by roadway tunneling blasting, thereby improving the underground air environment of roadway blasting tunneling and increasing the construction efficiency of rock burst roadways.

2. The method according to claim 1, wherein In step A, the ultra-deep pressure relief blast holes (4) are 1 - 2 m deeper than the tunneling blast holes (3) and have a diameter of about 42 mm.

3. The method according to claim 1 or 2, characterized in that In step A, a total of 4 - 6 ultra-deep pressure relief blast holes (4) are constructed at the three locations.

4. The method according to claim 1, characterized in that In step B, the diameter of the tunneling blast holes (3) is 20 - 30 cm.

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