Large goaf pre-buried foam block device subsequent filling roadway construction method

Abstract

The invention discloses a method for constructing a roadway through subsequent filling of a foam block pre-buried device in a large goaf, which comprises the following steps of: installing foam blocks in a goaf 11 after stoping in advance, carrying out high-strength cemented filling treatment on the goaf of a stope, and forming a roadway space by utilizing the foam blocks to resist and occupy the action of filling slurry / filling bodies; and after maintenance of the filling body is completed, the pressure-bearing, occupied and reusable foam blocks and the rubber air bags are removed, and finally the roadway project with the required size is constructed, and six specific steps and conditions exist. The method has the advantages that the damage influence range and degree, the construction cost and the construction labor intensity caused by caving rocks in the goaf can be greatly reduced, the construction efficiency is improved, and the safety of supporting operators under the filling body can be guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of metal and non-metal underground mines, and in particular to a method for constructing a tunnel by pre-buried foam block devices in large empty areas and then filling them. Background Art

[0002] In a mine that adopts the two-step phased emptying and subsequent filling method, when the bottom ore-exit hole (also used as a deep-hole rock-drilling tunnel in the "V" trench) is arranged in the middle of the stope rather than in the peach-shaped ore pillar, after the first-step stope is mined and filled, the second-step stope needs to reversely excavate and construct the ore-exit tunnel in the first-step filling body. However, due to the residual ore at the bottom of the first-step goaf (stope) and the insufficient strength of the filling body, it is difficult and risky to construct the ore-exit tunnel in the filling body, and short excavation and short support are required. Usually, advanced pipe shed + steel arch frame + anchor net + shotcrete support are used, and a large amount of support materials and manpower are invested, resulting in excessively high construction costs, complex processes, and low efficiency of tunnels in the filling body, which directly affects the economic benefits of the mine.

[0003] However, the existing reserved tunnel technology or methods mostly use lightweight materials that are easy to float and have poor impact resistance, which can easily cause the reserved tunnel to fail. At the same time, the existing reserved tunnel technology or methods basically invent some structures, and none of them describes in detail the construction process of the reserved tunnel in the empty area. Therefore, it is of great significance to develop a rock hydraulic coupling loading multi-physical field information acquisition system and method.

[0004] In order to solve the above problems, some people have successively disclosed: Patent CN 112943250 B "Method for reserving lanes in filling area" The patent material and structure adopt mold bag space placeholder, which is composed of solid modules and hollow core capsules, and there are deficiencies in materials, structure, transportation, splicing and filling process; CN208347787U "A lane reservation device" adopts a flexible, impermeable, weakly ductile, wear-resistant and corrosion-resistant material to form a tyre, and the tyre is expanded by injecting liquid or gas, which has deficiencies in materials and construction process; CN 108612544 B "A lane reservation device and a method for reserving lanes" is compared. This patent adopts a tyre and a tyre assembly, and needs to apply a release agent, tie and fix ropes, etc., which has deficiencies in specific implementation details; CN112505299 A "A new type of multi-size similar material simulation test tunnel reservation device", this patent adopts a horizontal bottom plate, a circular arc plate, a top plate and an umbrella-shaped support rod, focusing on the tunnel reservation in the simulation test, and has deficiencies in application scenarios, specific structures, and materials used; CN 216617577 U "A reserved tunnel device for underground cementing and filling", this patent adopts a tunnel retaining wall composed of a wire cage, a sand and gravel layer and a permeable layer, focusing on the construction and filling of the tunnel retaining wall, and has deficiencies in materials and construction technology.

[0005] Therefore, it is of great significance to develop a method for constructing a roadway by embedding foam blocks in a large empty area and then filling it. 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 constructing a roadway by embedding foam blocks in a large empty area and then filling it. It can not only construct roadways in the filling body at low cost and high efficiency, but also improve the construction efficiency of roadways in the filling body.

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

[0008] A method for constructing a roadway by embedding foam blocks in a large empty area and then filling it. Aiming at the problems of high construction cost, low construction efficiency, poor safety conditions in the roadway construction in the filling body caused by driving the roadway in the reverse direction in the filling body, as well as poor resistance of materials to the impact of falling rocks and difficulty in transporting structures or devices in the goaf in the conventional method of reserving roadways in large goafs, foam blocks are pre-installed in the goaf 11 after mining is completed, the goaf of the stope is treated with high-strength cementitious filling, and the foam blocks are used to resist and squeeze the filling slurry / filling body to form a roadway space. After the filling body is cured, the pressure-bearing, occupying, and reusable foam blocks and rubber airbags are removed, and finally a roadway project with the required size is constructed. The specific steps and conditions are as follows:

[0009] A. Level the bottom of the empty area. Before making foam 1, use a remote-controlled load-haul-dump (LHD) to clean and level the residual ore at the bottom of the goaf, which is convenient for device transportation and fixation. At the same time, weld a transportation base in the roadway near the goaf.

[0010] B. Make the transportation base. Foam 1 composed of rigid foam block materials has a certain weight and needs to be transported by a wheeled base traction.

[0011] C. Make the foam block device. First, install the bottom rubber airbag of the device on the transportation base, then install six layers of foam blocks, three blocks in each layer, then install the middle rubber airbag, and finally wrap the foam blocks with a flexible mesh.

[0012] D. Splice the foam blocks. The foam blocks need to be assembled and spliced one section at a time. Each section is gradually spliced into a whole by welding or riveting with the base of the previous section. Connect each section of the foam blocks through the transportation base with two steel wires, and combine the front-end steel wires into one and connect them to the tail end of the remote-controlled LHD.

[0013] F. Consign the foam block device. Use a remote-controlled LHD to tow the front-end steel wire of the device to consign the foam blocks. The length of each section consigned by the remote-controlled LHD into the goaf is about 3 m. Then assemble and splice the second section inside the roadway, and sequentially complete the assembly, splicing, and transportation of each subsequent section until completion.

[0014] G. The foam blocks are anchored with steel wire ropes. Anchor bolts are used to anchor the steel wire ropes outside the goaf into the rock mass of the roadway floor to resist the buoyancy of the filling slurry.

[0015] H. Goaf filling: After the foam blocks in the goaf are fixed, a filling retaining wall is constructed in the roadway for goaf filling. Limited by the buoyancy of the filling slurry and the bearing capacity of the foam block material, large-scale filling cannot be directly carried out and needs to be carried out in several stages. That is, for the 1st - 4th times, when the filling reaches the buoyancy balance, the allowable filling height is less than the allowable filling height of 5 m limited by the bearing limit of the material. After the 4th filling is completed, the actual filling body height reaches 5.2 m, and the filling body has completely buried the foam block device, and large-scale filling can be carried out subsequently.

[0016] I. Exposing the foam blocks: When the goaf filling body is cured for about 28 days and the strength reaches 3.5 - 5.0 MPa, the filling retaining wall is removed to expose the foam blocks.

[0017] J. Removing the foam blocks and roadway forming: Before removing the foam blocks, the rubber air bags need to be deflated and removed first to leave a space for the foam blocks to be easily removed. Then, the foam blocks around the space are removed from bottom to top. After each section is removed, a roadway with the required specifications can be formed in the filling body. After each section of the foam block is removed, shotcrete, bolting, and wire mesh support are immediately carried out on the reserved roadway to achieve roadway forming.

[0018] Compared with the prior art, the present invention has the following advantages or effects:

[0019] Because low-cost rigid material foam blocks are used and the foam blocks can be reused multiple times, the damage range and degree caused by the caving rock blocks in the goaf can be significantly reduced, and the construction cost can be greatly reduced. At the same time, due to the rubber air bags provided between and at the bottom of the foam blocks, after deflation, it is beneficial for the foam blocks to be easily removed, so the construction labor intensity and construction cost can be reduced, and the construction efficiency can be improved. In addition, because the flexible mesh sheets provided play a role in bundling the foam blocks into a whole in the initial stage, and after the foam is removed, there is flexible mesh pre-support, the safety of the support workers under the filling body can be guaranteed.

[0020] In short, the present invention can realize the construction of roadways in the filling body with low cost and high efficiency. The construction cost of roadways in the filling body is reduced by more than 30%, and the construction efficiency is increased by 30 - 100%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a front view schematic diagram of a foam block device for a method of constructing a roadway by subsequent filling of a large goaf with pre-buried foam blocks according to the present invention.

[0022] Figure 2 is Figure 1 a side view schematic diagram of the foam block device for the method of constructing a roadway by subsequent filling of the large goaf with pre-buried foam blocks shown.

[0023] Figure 3 For Figure 1 The schematic diagram of transporting the foam device in the goaf for the method of constructing a roadway by subsequently filling the pre-buried foam blocks in the large goaf shown in the figure.

[0024] Figure 4 For Figure 1 The schematic cross-sectional view of the roadway reserved by the foam block device after the goaf is filled for the method of constructing a roadway by subsequently filling the pre-buried foam blocks in the large goaf shown in the figure.

[0025] Each label in the attached drawings respectively represents:

[0026] 1. Foam block 2. Rubber airbag 3. Flexible net 4. Channel steel 5. Caster 6. Foam block device 7. Steel wire rope 8. Remote-controlled load-haul-dump machine 9. Roadway 10. Ore pillar 11. Goaf 12. Filling slurry / filling body

[0027] The present invention will be further described in detail below with reference to the attached drawings. Specific embodiments

[0028] As shown in the attached Figures 1 to 4 figure, for the method of constructing a roadway by subsequently filling the pre-buried foam blocks in the large goaf, aiming at the problems of high construction cost, low construction efficiency, poor safety conditions in the roadway construction in the filling body, and poor resistance of materials to rockfall impact damage and difficulty in transporting structures or devices in the goaf in the conventional method of reserving roadways in large goafs, it is characterized in that foam blocks 1 are installed and set in the goaf 11 after mining is completed in advance, the goaf 11 of the stope is subjected to high-strength cemented filling treatment, and the foam blocks 1 are used to resist and squeeze the filling slurry / filling body 12 to form the roadway 9 space. After the filling body is cured, the pressure-bearing, occupying, and reusable foam blocks 1 and rubber airbags 2 are removed, and finally a roadway project with the required size is constructed. The specific steps and conditions are as follows:

[0029] A. Level the bottom of the goaf. Before manufacturing the foam blocks 1, use a remote-controlled load-haul-dump machine 8 to clean and level the residual ore at the bottom of the goaf 11 to facilitate the transportation and fixation of the device. At the same time, weld a transportation base in the roadway near the goaf 11;

[0030] B. Manufacture the transportation base. The foam blocks 1 composed of rigid foam block materials have a certain weight and need to be transported by a wheeled base;

[0031] C. Manufacture the foam block device. First, install the bottom rubber airbag of the device on the transportation base, then install six layers of foam blocks 1, three in each layer, then install the middle rubber airbag 2, and finally wrap the foam blocks 1 with the flexible net 3 mesh;

[0032] D. Assembly of the foam blocks 1. The foam blocks 1 need to be assembled and joined one by one. Each section is gradually joined into a whole by welding or riveting to the base of the previous section. Two steel wire ropes 7 are used to connect each section of the foam block 1 through the transportation base. The front-end steel wire ropes 7 are combined into one and connected to the tail end of the remote-controlled scraper 8.

[0033] F. Shipment of the foam block device. The front-end steel wire rope 7 of the traction device of the remote-controlled scraper is used to ship the foam blocks 1. The remote-controlled scraper 8 ships about 3 m in length of one section into the goaf 11. Then, the second section is assembled and joined inside the roadway. Subsequently, the assembly, joining, and transportation of each subsequent section are completed in turn until it is finished.

[0034] G. Anchoring of the foam blocks 1 with steel wire ropes 7. The steel wire rope 7 outside the goaf is anchored into the rock mass of the roadway floor with bolts to resist the buoyancy of the filling slurry.

[0035] H. Filling of the goaf. After the foam blocks 1 in the goaf 11 are fixed, a filling retaining wall is constructed in the roadway to fill the goaf 11. Limited by the buoyancy of the filling slurry and the bearing capacity of the foam block 1 material, large-scale filling cannot be directly carried out and needs to be carried out in batches. That is, for the 1st - 4th times, the allowable filling height when the buoyancy balance is reached is less than the allowable filling height of 5 m limited by the bearing limit of the material. After the 4th filling is completed, the actual height of the filling body reaches 5.2 m, and the filling body has completely buried the foam block device. Subsequently, large-scale filling can be carried out.

[0036] I. Exposing the foam blocks. When the filling body in the goaf 11 is cured for about 28 days and the strength reaches 3.5 - 5.0 MPa, the filling retaining wall is removed to expose the foam blocks 1.

[0037] J. Demolishing the foam blocks and forming the roadway. Before demolishing the foam blocks 1, the rubber airbag 2 needs to be deflated and removed first to leave a space conducive to demolition for the uncompressed foam blocks 1. Then, the foam blocks 1 around the space are demolished from bottom to top. After each section is demolished, a roadway of the required specification can be formed in the filling body. After each section of the foam blocks 1 is demolished, the reserved roadway is immediately supported by shotcrete, anchor net, and steel bar to form the roadway.

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

[0039] In the step B, the wheeled base transportation structure consists of 2 longitudinal channel steels with a spacing of 3.8 m as the chassis, and 3 transverse channel steels on its upper part are welded every 1 m.

[0040] In the step B, casters 5 with a diameter of 150 mm and a wheel width of 75 mm are installed at the bottom of the longitudinal channel steel, and the installation height is 210 mm. A flat plate with a size of 205 mm × 150 mm is provided on the caster 5.

[0041] In the step C, the length:width:height of the foam block 1 = 3 m:1.2 m:0.6 m.

[0042] The rubber airbag 2 in step C has a length:width:height=3m:3.8m:0.15m.

[0043] The flexible net 3 in step C has a length:width of 10m:3m, a wire diameter of 4mm, and a mesh size of 80mm.

[0044] In step H, when the filling of the goaf 11 reaches buoyancy balance, the first to fourth filling heights allowed are 0.4m, 0.7m, 1.4m, and 2.1m respectively.

[0045] As described above, the present invention can be better implemented. The above embodiments are only the best implementation methods of the present invention, but the implementation methods of the present invention are not limited by the above embodiments. Other changes, modifications, replacements, combinations, and simplifications made without departing from the spirit and principle of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for constructing tunnels by pre-buried foam blocks in large goafs and then filling them. This method aims to solve the problems of high construction cost, low construction efficiency, and poor safety conditions of tunnels in the back-dig tunnels in the backfills, as well as the poor ability of materials to resist rockfall impact and damage in conventional large goafs, and the difficulty in transporting structures or devices in the goafs. It is characterized by A foam block (1) is installed in advance in the goaf (11) where mining is completed, and a high-strength cement filling treatment is performed on the goaf (11). The foam block (1) is used to resist and squeeze the filling slurry / filling body (12) to form a tunnel (9) space. After the filling body is cured, the pressure-bearing, position-occupying, reusable foam block (1) and rubber airbag (2) are removed, and finally a tunnel project of a desired size is constructed. The specific steps and conditions are as follows: A. Leveling the bottom of the goaf. Before making the foam block (1), a remote-controlled scraper (8) is used to clean and level the residual ore at the bottom of the goaf (11) to facilitate transportation and fixation of the device. At the same time, a transportation base is welded in the tunnel near the goaf (11); B. The transport base is made of a foam block (1) made of a hard foam block material, which has a certain weight and needs to be towed and transported by a wheeled base; C. The foam block device is manufactured by first setting up a rubber airbag (2) at the bottom of the device on a transport base, then installing six layers of foam blocks (1) thereon, with three blocks in each layer, then installing the middle rubber airbag (2), and finally wrapping the foam block (1) with a flexible net (3); D. Splicing of the foam blocks (1), assembling and splicing the foam blocks (1) one section at a time, and gradually splicing each section into a whole by welding or riveting with the base of the previous section, and connecting each section of the foam blocks (1) through the transport base with two steel wire ropes (7), and the front end steel wire ropes (7) are combined into one to connect the rear end of the remote-controlled scraper (8); F. The foam block device is transported by using a remote-controlled scraper traction device with a front-end steel wire rope (7) to transport the foam block (1). The remote-controlled scraper (8) transports a section into the goaf (11). Each section is about 3 meters long. Then, the second section is assembled and spliced ​​inside the tunnel. The assembly, splicing and transportation of each subsequent section are completed in sequence. G. The foam block (1) is anchored with a steel wire rope (7), and the steel wire rope (7) outside the goaf is anchored into the rock mass of the tunnel floor by an anchor rod to resist the buoyancy of the filling slurry; H. Goaf filling: After the foam blocks (1) in the goaf (11) are fixed, a filling retaining wall is constructed in the tunnel to fill the goaf (11). Due to the buoyancy of the filling slurry and the pressure bearing capacity of the foam blocks (1), large-scale filling cannot be carried out directly, and it is necessary to carry out filling in stages. That is, for the 1st to 4th times, the allowable filling height when the filling reaches buoyancy balance is less than the 5m allowable filling height of the material's pressure bearing limit. After the 4th filling is completed, the actual filling body height reaches 5.2m, and the filling body has completely buried the foam block device, and large-scale filling can be carried out later; I. Exposing the foam blocks: when the filling body of the goaf (11) has been cured for about 28 days and the strength reaches 3.5-5.0 MPa, the filling retaining wall is removed to expose the foam blocks (1); J. Removal of foam blocks and tunnel formation. Before removing the foam blocks (1), the rubber airbag (2) must be deflated and removed to leave a gap for the compressed foam blocks (1) to facilitate removal. Then, the foam blocks (1) around the gap are removed from bottom to top. After each section is removed, a tunnel of the required specifications can be formed in the filling body. After each section of the foam blocks (1) is removed, the reserved tunnel is immediately supported by a spray anchor net to achieve tunnel formation.

2. The method according to claim 1, characterized in that In step B, the wheeled base transport structure is composed of two longitudinal channel steels with a spacing of 3.8m as the base frame, and three transverse channel steels on the upper part are welded every 1m.

3. The method according to claim 1 or 2, characterized in that In step B, a caster (5) with a diameter of 150 mm and a wheel width of 75 mm is installed at the bottom of the longitudinal channel steel, and the installation height is 210 mm. A flat plate with a size of 205 mm×150 mm is provided on the caster (5).

4. The method according to claim 1, characterized in that The foam block (1) in step C has a length:width:height=3m:1.2m:0.6m.

5. The method according to claim 1, characterized in that The length: width: height of the rubber airbag (2) in step C is 3m: 3.8m: 0.15m.

6. The method according to claim 1, characterized in that The flexible net (3) in step C has a length:width=10m:3m, a wire diameter of 4mm, and a mesh size of 80mm.

7. The method according to claim 1, characterized in that When the filling of the goaf (11) in step H reaches buoyancy balance, the first to fourth filling heights allowed are 0.4m, 0.7m, 1.4m and 2.1m respectively.

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