Method for filling reserved roadway in goaf based on flexible molding plate and water bag combined structure

Abstract

The invention discloses a goaf filling reserved roadway method based on a flexible molding plate and water bag combined structure. A light molding plate and inflatable bag structure for reducing the transportation weight of the structure is adopted, a bag body is wrapped by the molding plate to resist damage of rockfall in a goaf and protect the inner bag body to be safe, water or other liquid with large weight is injected into the bag body after the structure is transported to the goaf so as to increase the weight of the structure to resist buoyancy damage of filling slurry, and after the goaf is filled, the filling slurry is filled. After maintenance of the filling body is completed, the mining rubber air bag and the molding plate which can be repeatedly used for 5-10 times are recycled, and finally the roadway project with the needed size is obtained, the specific steps and conditions are seven, the problems that transportation is inconvenient, filling slurry buoyancy harm is caused, and falling rock impact damage is caused in the process of filling the reserved roadway in the goaf can be solved, the construction cost can be reduced, and the construction efficiency is improved. The construction efficiency is improved, and safe, efficient and low-cost roadway reserving is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal and non-metal underground mines, and in particular to a method for reserving a roadway in an open stope backfill by using a combined structure of a flexible molding plate and a water bag. Background Art

[0002] For mines adopting the open stope subsequent backfill method or the open stope method, when it is necessary to pass through the open stope to mine adjacent ore bodies, it is often necessary to backfill the open stope and reserve a roadway. This method is to pre-set air bags or lightweight modular materials in the open stope, and then remove these materials after the open stope is backfilled to form a roadway. However, due to the large height of the mined-out area, the roof or the two sides are prone to the risk of rock block caving. The air bags have poor impact resistance to falling rocks. If they are hit, air leakage will occur, resulting in the failure of the reserved roadway. In addition, the modular materials are light. When the filling slurry is poured into the open stope, the buoyancy of the filling slurry is large, and such lightweight materials will immediately float. It is often necessary to use steel to increase the weight or fix them with ropes. The towing equipment with a large power is required for towing such structures in the open stope, and the towing difficulty is great, which reduces the construction efficiency of reserving a roadway in the open stope backfill and increases the construction cost.

[0003] To solve the above problems, the following have been successively disclosed: 1. Patent CN 112943250 B, "Method for reserving roadway in filling area", whose structure and materials adopt a formwork bag space occupier, which is composed of a solid occupancy module and a hollow capsule. The formwork bag is sewn from geotextile, with a steel skeleton and a steel mesh inside, and support bolts outside. The construction process is to divide the goaf into a filling space and a reserved space, construct a formwork bag space occupier in the reserved space, construct a filling retaining wall, pour filling slurry, and after curing, remove the retaining wall and the formwork bag space occupier to form a roadway. The function and purpose are to reduce the amount of work for closing the retaining wall, realize the reuse of underground engineering and space, reduce the filling cost, and reduce the amount of tunneling work and mining cost; 2. CN 113062766 A, "Method for reserving space in roadway", whose structure and materials adopt a solid occupancy module and a hollow capsule. The solid occupancy module is made of a lightweight foam block or a foamed block, with a protective formwork bag outside, and the hollow capsule is filled with an occupancy body. The construction process is to divide the roadway into a filling space and a reserved space, construct a formwork bag space occupier in the reserved space, construct a filling retaining wall, pour filling slurry, and after curing, remove the retaining wall and the formwork bag space occupier. The function and purpose are to reduce the amount of work for closing the retaining wall, realize the reuse of underground space, reduce the filling cost, and reduce the amount of tunneling work and mining cost; 3. CN 214787400 U, "A reserved structure for mine roadway using cemented filling mining method", whose structure and materials adopt a steel formwork false roadway, and the passage is connected by cylindrical precast parts. The precast parts include arc-shaped templates, which are connected by bolts. The construction process is to lay a cushion layer in the roadway, place the passage, set cross braces and vertical braces, and form a reserved roadway after filling. The function and purpose are to deal with unsafe roadways, retain the functions of the original roadway, avoid re-tunneling roadways, and save investment; 4. CN 115013049 B, "A device for reserving roadway in filling goaf and its construction technology", whose structure and materials adopt an inflatable air cushion. The air cushion is composed of an outer air cushion fiber cloth and an inner air cushion fiber cloth, and is divided into multiple inflatable chambers inside. The construction process is to install the inflatable air cushion, inflate to form a space occupier, construct a filling retaining wall, pour filling slurry, and after curing, remove the retaining wall and the air cushion. The function and purpose are to reduce the amount of work for closing the retaining wall, realize the reuse of underground engineering and space, reduce the filling cost, and reduce the amount of tunneling work and mining cost; 5. CN 219841235U, "A non-metallic corrugated pipe connection reinforcement structure for underground reserved roadway", whose structure and materials adopt a non-metallic corrugated pipe, which is connected by a joint tape, with a large-diameter corrugated pipe sleeved outside, and a grouting layer is filled. The construction process is to connect the small-diameter corrugated pipe, sleeve the large-diameter corrugated pipe, and grout to form a grouting layer for strengthening the connection of the corrugated pipes. The function and purpose are to solve the problem of easy breakage and slurry leakage at the connection of the corrugated pipes and improve the strength of the connection of the corrugated pipes; 6.CN 208347787 U, "A roadway reservation device", and CN108612544 B, "A roadway reservation device and a method for reserving a roadway", both use a straight cylindrical arch formwork and an arch body component in terms of structure and materials. The arch formwork is made of a flexible impermeable material with a hollow interlayer inside, into which liquid or gas can be injected. During the construction process, the arch formwork is transported to the construction site, the arch body component is installed, a release agent is applied, fixing ropes are tied, liquid or gas is injected, mortar is filled, and after curing, the arch formwork and the arch body component are removed. Their functions and purposes are to replace the traditional method of reserving roadways in mined - out areas, reduce labor intensity, improve construction efficiency, and lower construction costs; 7. CN 112505299 A, "A new type of roadway reservation device for multi - size similar material simulation tests", its structure and materials use a horizontal bottom plate, a left arc plate, a right arc plate, a semi - cylindrical roof plate, and umbrella - shaped support members, which are composed of steel and threaded components. The construction process is for indoor simulation tests. By assembling the bottom plate, arc plates, and roof plate, a roadway model is formed. Its functions and purposes are for indoor simulation tests, to study the mechanical phenomena in mine exploitation, and to provide tests. Its structure and materials use a wire cage, a sand layer, and a permeable layer, with sand data filled in the wire cage; 8. CN 216617577 U, "A roadway reservation device for underground cemented filling", its structure and materials have the permeable layer located between the sand layer and the inner wall of the wire cage. The construction process is to set two roadway - retaining walls in the chamber. The retaining walls are composed of multiple detachably connected retaining wall monomers. After filling operations, a reserved roadway is formed. Its functions and purposes are to solve the stability problem of the reserved roadway during underground cemented filling, prevent the leakage of filling slurry, and ensure the capping rate and the stability of the filling body.

[0004] The comparative analysis of the above patents by our research group is as follows: Structure and materials: Although there are similarities in the construction of reserved roadways in some patents, there are deficiencies in the impact resistance and buoyancy resistance of the materials; in other patents, such as Patents 1, 2, 6, and 7, although similar forms of geotextile bags or arch centering structures are also used, they mainly achieve reserved roadways through the combination of solid modules and hollow capsules, with deficiencies such as the light weight of the water capsules; Patents 3, 4, and 8 adopt completely different structures, such as channel support structures, inflatable air cushions, and retaining walls for remaining roadways, and these structures are different from the application method in terms of function. Construction process: Although there are also similarities in the construction processes of other patents, such as steps like constructing geotextile bag space occupiers, filling, and demolition, there are deficiencies in specific operations. For example, the construction processes of Patents 1 and 2 focus on the segmented construction and gradual pushing of geotextile bag space occupiers, while ignoring the adjustment of structural weight, and the construction processes of Patents 3, 4, and 8 focus on the construction of channel support structures, the installation and filling of inflatable air cushions, and the setting and filling of retaining walls for remaining roadways respectively; Function and purpose: Patents 1 and 2 mainly reduce the closed project volume of retaining walls through geotextile bag space occupiers to achieve the reuse of underground space, Patent 3 aims at the treatment of unsafe roadways and the resistance to hydrostatic pressure respectively, although Patent 4 is also related to filling and reserving roadways in mined - out areas, the inflatable air cushion and water capsule combination structure it adopts has obvious differences, and Patent 5 aims at the connection reinforcement of corrugated pipes and the reservation of simulated test roadways respectively, and the function is completely different from the application method.

[0005] Therefore, it is of great significance to develop a method for filling and reserving roadways in mined - out areas based on the combination structure of flexible molding plates and water capsules. Summary of the Invention

[0006] The task of the present invention is to overcome the deficiencies of the prior art and provide a method for filling and reserving roadways in mined - out areas based on the combination structure of flexible molding plates and water capsules, which can not only solve problems such as inconvenient transportation, buoyancy hazards of filling slurries, and impact damage of caving rocks during the process of filling and reserving roadways in mined - out areas, but also reduce construction costs, improve construction efficiency, and achieve safe, efficient, and low - cost reservation of roadways.

[0007] The task of the present invention is completed through the following technical solutions:

[0008] Method for reserving roadway in goaf filling based on flexible molding plate and water bag combination structure. Aiming at the problems in the process of reserving roadway in existing goaf filling, such as large weight of structure or device, inconvenient transportation, buoyancy hazard of filling slurry and impact damage of falling rocks, a lightweight molding plate + air-filled bag structure is adopted to reduce the transportation weight of the structure. The molding plate is used to wrap the bladder to resist the damage of falling rocks in the goaf and protect the safety of the internal bladder structure. After being transported to the goaf, water or other liquids with a larger weight are injected into the bladder to increase the structure weight and resist the buoyancy hazard of the filling slurry. After the goaf is filled and the filling body is cured, the mine-used rubber bladder and the molding plate that can be reused 5 - 10 times are recovered, and finally the roadway project with the required size is obtained. The specific steps and conditions are as follows:

[0009] A. Device manufacturing: First, in a safe roadway, a device bottom plate is welded with 3 channel steels 8 with a longitudinal length of 3 - 5 m and 3 - 5 steel plates 7 with a thickness of 6 - 8 mm. Then, the mine-used rubber bladder 2 is inflated by injecting gas until the internal pressure reaches 0.1 MPa to form a bladder in the shape of a roadway. Finally, a customized and cut lightweight molding plate 3 is wrapped outside the bladder 3, and it is tied to the steel bottom plate with a steel wire rope 4 to form an integrated flexible device of a flexible molding plate + air bag combination structure;

[0010] B. Device transportation and layout: First, a remote-controlled load-haul-dump vehicle 10 is used to clean and level the bottom residual ore, waste rock, etc. in the goaf 12 for the transportation of the structure. Then, the device is dragged into the goaf by the steel wire rope 4 towed at the tail end of the remote-controlled load-haul-dump vehicle 10, and the two devices are connected by welding or riveting;

[0011] C. Device water injection and air release: When the device is transported to the designed position, a water injection pump is used in the roadway 11 to inject water into the mine-used rubber bladder 2 of the device through a water injection pipe. During the water injection process, the valve of the air injection / air release pipe 5 is opened to slowly release air, and the internal pressure of the mine-used rubber bladder 2 is always maintained at 0.1 MPa through a pressure gauge until most of the gas in the mine-used rubber bladder 2 is discharged to form a flexible structure with a molding plate 2 wrapping the water bag;

[0012] D. Goaf filling: After building a filling retaining wall near the goaf 12 opening, the goaf 12 is filled. Limited by factors such as the hydraulic pressure and buoyancy of the filling slurry / filling body 14, the first filling height is not more than 3 m; after the filling body is cured for 24 hours, the second filling is carried out, and the filling height is not more than 5 m. After that, large-scale filling can be carried out.

[0013] E. Water bag water drainage and molding plate removal: When the filling body in the goaf is cured for about 28 days or reaches a strength of 3.5 MPa - 5 MPa, the filling retaining wall is removed to expose the water bag and the molding plate 3. The valve of the water drainage pipe of the water bag is opened to drain the water in the water bag into the roadway 11, then the mine-used rubber bladder 2 is removed, and the molding plate 3 is removed;

[0014] F. Roadway formation and support: After the device is removed for 3 - 5 m, shotcrete with wire mesh support is first carried out on the exposed filling slurry / filling body 14, and then the removal of the second - stage device and the support of the bare roadway are started until the construction of all reserved roadways is completed;

[0015] G. Repeated reuse of the molded board and the mine - used rubber airbag. If the mine - used rubber airbag 2 is not damaged or leaking air, and the molded board 3 is not broken or severely sunken, it can be reused 5 - 10 times in the operation of new reserved roadways until it is scrapped.

[0016] Compared with the prior art, the present invention has the following advantages or effects:

[0017] Because the molded - board protection + capsule - medium switching and staged filling process is adopted, the coordinated problems of transportation, anti - floating, and anti - impact in the traditional method are solved. Therefore, employees do not need to enter the goaf to avoid the risk of caving. At the same time, because the main materials of the device, the molded board and the capsule, are reused, the construction cost can be reduced by more than 60%. In addition, because the modular structure is adopted to achieve rapid construction, the construction efficiency of the roadway in the filling body can be increased by 100%.

[0018] In summary, the present invention forms a roadway shape in advance at the bottom of the goaf by laying a flexible combined structure that is convenient for consignment, reusable, and has a certain weight at the bottom of the goaf. The main production materials of this flexible structure are reusable materials with very low material costs, reducing the construction cost of the reserved roadway. The molded board wrapped outside can effectively reduce the harm of falling stones in the goaf and protect the safety and reliability of the device in the goaf.

[0019] The innovation points of the present invention are as follows:

[0020] 1. Adopting the molded - board protection + capsule - medium switching and staged filling process to solve the coordinated problems of transportation, anti - floating, and anti - impact in the traditional method, and personnel do not need to enter the goaf to avoid the risk of caving.

[0021] 2. The main materials of the device - the molded board and the capsule material - can be reused, which can reduce the construction cost.

[0022] 3. Adopting the modular structure to achieve rapid construction can improve the construction efficiency of the roadway in the filling body.

[0023] 4. Laying a flexible combined structure that is convenient for consignment, reusable, and has a certain weight at the bottom of the goaf to form a roadway shape in advance at the bottom of the goaf. The molded board wrapped outside can effectively reduce the harm of falling stones in the goaf and protect the safety and reliability of the device in the goaf. Description of the Drawings

[0024] Figure 1A method for reserving roadway in goaf filling based on a combined structure of flexible molding board and water bag proposed according to the present invention. Schematic cross-section of the flexible molding board + water bag structure.

[0025] Figure 2 For Figure 1 Schematic diagram of the transportation of the flexible molding board + water bag device in the goaf for the method of reserving roadway in goaf filling based on the combined structure of flexible molding board and water bag shown.

[0026] Figure 3 For Figure 1 Schematic cross-section of the reserved roadway of the flexible molding board + water bag device after goaf filling for the method of reserving roadway in goaf filling based on the combined structure of flexible molding board and water bag shown.

[0027] Each label in the attached drawings respectively represents:

[0028] 1. Water; 2. Mine-used rubber airbag; 3. Molding board; 4. Steel wire rope; 5. Air injection / drainage pipe; 6. Water injection / drainage pipe; 7. Steel plate; 8. Channel steel; 9. Steel wire rope; 10. Remote control LHD; 11. Roadway; 12. Goaf; 13. Ore body

[0029] The present invention will be further described in detail below with reference to the attached drawings. Specific implementation manners

[0030] As shown in the attached Figures 1 to 3 For the method of reserving roadway in goaf filling based on the combined structure of flexible molding board and water bag, aiming at the problems in the existing process of reserving roadway in goaf filling, such as the large weight of the structure or device, inconvenient transportation, the buoyancy hazard of the filling slurry, and the impact damage of the falling rocks, a lightweight molding board + air-filled bag structure is adopted to reduce the transportation weight of the structure. The molding board is used to wrap the bladder to resist the damage of the falling rocks in the goaf and protect the safety of the internal bladder structure. After being transported to the goaf, water or other liquids with a larger weight are injected into the bladder to increase the structure weight to resist the buoyancy hazard of the filling slurry. After the goaf is filled, after the filling body is cured, the mine-used rubber airbag and the molding board that can be reused 5 - 10 times are recovered, and finally the roadway project with the required size is obtained. The specific steps and conditions are as follows:

[0031] A. Device manufacturing: First, in a safe roadway, a device bottom plate is welded with 3 channel steels 8 with a longitudinal length of 3 - 5 m and 3 - 5 steel plates 7 with a thickness of 6 - 8 mm. Then, the mine-used rubber airbag 2 is inflated by injecting air until the internal pressure reaches 0.1 MPa to form a bladder in the shape of a roadway. Finally, a customized and cut lightweight molding board 3 is wrapped outside the bladder 3, and it is tied to the steel bottom plate with a steel wire rope 4 to form an integral flexible device of a flexible molding board + airbag combination structure.

[0032] B. Device transportation and arrangement: First, use the remote-controlled load-haul-dump (LHD) vehicle 10 to clean and level the bottom residual ore, waste rock, etc. in the goaf 12 for the transportation of the structure. Then, the steel wire rope 4 at the tail end of the remote-controlled LHD vehicle 10 is used to drag the device into the goaf, and the two devices are connected by welding or riveting;

[0033] C. Device water injection and air release: When the device is transported to the designed position, in the roadway 11, use a water injection pump to inject water into the mining rubber airbag 2 of the device through the water injection pipe. During the water injection process, open the valve of the air injection / discharge pipe 5 to slowly release air, and control the internal pressure of the mining rubber airbag 2 to always maintain at 0.1 MPa through the pressure gauge until most of the gas in the mining rubber airbag 2 is discharged, forming a flexible structure with a molded board 2 wrapping the water bag;

[0034] D. Goaf filling: After building a filling retaining wall near the mouth of the goaf 12, carry out filling treatment on the goaf 12. Limited by factors such as the hydraulic pressure and buoyancy of the filling slurry / filling body 14, the first filling height is not more than 3 m; after the filling body is cured for 24 hours, carry out the second filling, and the filling height is not more than 5 m. After that, large-scale filling can be carried out.

[0035] E. Water bag water discharge and molded board removal: When the filling body in the goaf is cured for about 28 days or reaches a strength of 3.5 MPa - 5 MPa, remove the filling retaining wall, expose the water bag and the molded board 3, open the valve of the water discharge pipe of the water bag, discharge the water in the water bag into the roadway 11, then remove the mining rubber airbag 2, and remove the molded board 3;

[0036] F. Roadway shaping and support: After removing one section of the device with a length of 3 - 5 m, first carry out shotcrete, bolting and meshing support on the exposed filling slurry / filling body 14, and then start the removal of the second section of the device and the support operation for the exposed roadway until the construction of all reserved roadways is completed;

[0037] G. Repeated reuse of the molded board and the mining rubber airbag: If the mining rubber airbag 2 is not damaged or leaking air, and the molded board 3 is not broken or severely dented, it can be reused 5 - 10 times in the operation of the new reserved roadway until it is scrapped.

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

[0039] In step A, the length: width: height of the airbag body of the roadway shape is 3 - 5 m: 3.2 m: 3.6 m.

[0040] In step A, the length: width of the lightweight molded board 3 is 3 - 5 m: 0.2 m.

[0041] In step A, the length: width: height of the flexible device is 3 - 5 m: 3.8 m: 3.8 m.

[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 by 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 modes and are all included in the protection scope of the present invention.

Claims

1. A method for filling reserved tunnels in empty areas based on a combined structure of a flexible molded plate and a water bag. This method aims to solve the problems of heavy weight of the structure or device in the process of filling reserved tunnels in empty areas, inconvenient transportation, buoyancy hazards of filling slurry, and impact damage caused by falling rocks. It is characterized by A lightweight molded plate (3) + mining rubber airbag (2) structure is used to reduce the transportation weight of the structure, and the molded plate (3) is used to wrap the bag body to resist the damage of falling rocks in the empty area and protect the internal bag body structure. After being transported to the empty area (12), a large amount of water (1) or other liquid is injected into the bag body to increase the structural weight to resist the buoyancy damage of the filling slurry. After the empty area is filled, the filling body is cured and the mining rubber airbag (2) and the molded plate (3) that can be reused 5 to 10 times are recovered, and finally a tunnel project of the required size is obtained. The specific steps and conditions are as follows: A. Device manufacturing: First, three longitudinally 3-5m long channel steels (8) and three to five 6-8mm thick steel plates (7) are used to weld the device bottom plate in a safe tunnel. Then, the mining rubber airbag (2) is inflated by air injection to make its internal pressure reach 0.1MPa, forming a tunnel-shaped bladder. Finally, a customized and cut lightweight molded plate (3) is used to wrap the outside of the bladder, and it is tied to the steel bottom plate with a steel wire rope (4) to form a whole. Thus, a flexible device with a flexible molded plate + airbag combined structure is manufactured. B. The equipment is transported and arranged. First, a remote-controlled scraper (10) is used to clean and level the residual ore and waste rock at the bottom of the empty area (12) to facilitate the transportation of the structure. Then, the remote-controlled scraper (10) uses a wire rope (4) at the tail end to drag the equipment into the empty area (11). The two equipments are connected by welding or riveting. C. Water injection and air release of the device. When the device is transported to the designed location, a water injection pump is used in the tunnel (11) to inject water into the mining rubber airbag (2) of the device through the water injection pipe. During the water injection (1) process, the valve of the air injection / air release pipe (5) is opened to slowly release air. The internal pressure of the mining rubber airbag (2) is always maintained at 0.1 MPa through the pressure gauge until most of the gas in the mining rubber airbag (2) is discharged, forming a flexible structure in which the molded plate (2) wraps the water bag; D. Filling of the empty area: After constructing the filling retaining wall near the mouth of the empty area (12), the empty area (12) is filled. Due to the hydraulic pressure and buoyancy of the filling slurry / filling body (14), the first filling height is not more than 3m. After the filling body is cured for 24 hours, the second filling is carried out, and the filling height is not more than 5m. After that, large-scale filling can be carried out. E. Draining the water bag and removing the mold plate: When the filling body in the empty area is cured for about 28 days or reaches a strength of 3.5MPa to 5MPa, remove the filling retaining wall, expose the water bag and the mold plate (3), open the valve of the water bag drainage pipe, and drain the water in the water bag into the tunnel (11), then remove the mining rubber air bag (2) and remove the mold plate (3); F. Tunnel formation and support: After removing a section of the device for 3 to 5 m, the exposed filling slurry / filling body (14) is first supported by spray anchor mesh, and then the removal of the second section of the device and the bare tunnel support operation are started until the construction of all reserved tunnels is completed; G. Repeated reuse of molded plates and mining rubber airbags. If the mining rubber airbag (2) is not damaged or leaking, and the molded plates (3) are not broken or seriously dented, they can be reused 5 to 10 times in new reserved tunnel operations until they are scrapped.

2. The method according to claim 1, characterized in that The length, width and height of the capsule in the tunnel shape of step A are 3-5m: 3.2m: 3.6m.

3. The method according to claim 1, characterized in that The lightweight molded board (3) in step A has a length:width of 3-5 m:0.2 m.

4. The method according to claim 1, 2 or 3, characterized in that The flexible device in step A has a length: width: height = 3-5 m: 3.8 m: 3.8 m.

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