Roadway forming method of goaf filling pre-embedded water filtering structure

Abstract

A roadway forming method of a goaf filling pre-embedded water filtering structure comprises the steps that a water filtering steel framework and double filter cloth 3 are arranged in a goaf (14) in advance, redundant water of filling slurry can be secreted out, and the hydraulic pressure of most of the filling slurry outside the structure can be counteracted for high-strength cemented filling treatment; filling slurry or a filling body is resisted and occupied in a goaf 14 to form a roadway space to obtain a roadway project with the needed size and combined pre-supporting of a steel framework and a flexible net, the steel framework capable of filtering water and having certain rigidity is arranged at the bottom of the goaf 14, a roadway occupied space is formed in advance, the geotechnical cloth covering the roadway occupied space can secrete excessive water, and the roadway occupied space can be used for supporting the goaf 14. The method has six specific process steps and conditions, and has the advantages that the construction efficiency can be improved, the construction cost can be reduced, and the operation safety can be guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of metal and non-metal underground mines, and particularly to a roadway forming method for a pre-buried water filtration structure in stope backfilling. Background Art

[0002] In mines adopting the two-step open stoping and subsequent filling method or the open stoping method, when mining an ore body that needs to pass through a stope, it is often necessary to fill the stope, and then construct a roadway project in the filling body to reach the ore body to be mined. However, affected by the residual ore at the bottom of the stope and the insufficient strength of the filling body, it is difficult and risky to excavate the roadway in the filling body. Short excavation and short support are required. Usually, advanced pipe roofs + steel arches + anchor nets + shotcrete support are adopted, which requires a large amount of support materials and manpower, resulting in too high construction costs and low efficiency of the roadway in the filling body, directly affecting the economic benefits and safety of ore body mining. Existing reserved roadway technologies or methods mostly use lightweight materials that are easy to float and have poor impact resistance, which are likely to cause the failure of the reserved roadway. At the same time, basically, some structures are invented, and the construction technology of the reserved roadway in the stope is not described in detail.

[0003] In order to solve the above problems, some people have successively disclosed: Patent CN 112943250 B "Method for reserving tunnels in filling areas", its structure and materials are to use a mold bag space placeholder, which is composed of a solid placeholder module and a hollow core capsule. The mold bag is made of geotextile, with a steel skeleton and a steel mesh inside and supporting anchor rods outside. The construction process is to divide the goaf into a filling space and a reserved space, construct a mold bag space placeholder in the reserved space, construct a filling retaining wall, pour the filling slurry, and remove the retaining wall and the mold bag space placeholder after curing to form a tunnel. The function and purpose are to reduce the amount of retaining wall closure engineering, realize the reuse of underground engineering and space, reduce the filling cost, and reduce the amount of excavation engineering and mining costs, but there are obvious differences in specific structural design, material use and construction steps; CN 113062766 A "Method for reserving space in tunnels", its structure and materials are solid placeholder modules and hollow bladders. The solid placeholder modules are made of lightweight foam blocks or foamed blocks, with outer protective mold bags, and the hollow bladders are filled with placeholders. The construction process is to divide the tunnel into filling space and reserved space, construct mold bag space placeholders in the reserved space, construct filling retaining walls, pour filling slurry, and remove the retaining walls and mold bag space placeholders after maintenance. The function and purpose is to reduce the amount of retaining wall closure engineering, realize the reuse of underground space, reduce filling costs, reduce excavation engineering and mining costs, and there are obvious deficiencies in the method and structure of reserving space; CN 214787400 U "A reserved structure for mine tunnels using cemented filling mining method", its structure and materials are steel template fake tunnels, the tunnels are connected by cylindrical prefabricated parts, the prefabricated parts include arc templates, connected by bolts, construction process: the patent lays a cushion layer in the tunnel, places the tunnel, sets horizontal and vertical braces, and forms a reserved tunnel after filling; "The tunnel forming method of pre-buried water filtration structure in empty area filling" makes and transports the water filtration structure after the bottom of the empty area is leveled, and fills it in batches. After maintenance, part of the structure is removed to form a tunnel. The function and purpose is to deal with unsafe tunnels, retain the function of the original tunnels, avoid re-digging tunnels, and save investment. There are deficiencies in structural design and construction methods; CN 115013049 B “A device for filling reserved tunnels in goafs and its construction process”, its structure and material are inflatable air cushions, which are composed of an outer layer of air cushion fiber cloth and an inner layer of air cushion fiber cloth, and are divided into multiple inflatable chambers. The construction process is to install the inflatable air cushions, inflate them to form space placeholders, build filling retaining walls, pour filling slurry, and remove the retaining walls and air cushions after maintenance. Its function and purpose is to reduce the amount of retaining wall closure engineering, realize the reuse of underground engineering and space, reduce filling costs, reduce excavation engineering and mining costs, and there are deficiencies in structure and construction methods;CN 219841235 U, "A Non-Metallic Bellows Connection Reinforcement Structure for Underground Reserved Roadways", uses a non-metallic bellows in its structure and materials, connects through a joint tape, sleeved with a large-diameter bellows on the outside, and filled with a grouting layer. The construction process is to connect small-diameter bellows, sleeve large-diameter bellows, and grout to form a grouting layer for strengthening the connection of the bellows. Its function and purpose are to solve the problem of easy breakage and slurry leakage at the connection of the bellows, and improve the strength of the connection of the bellows. There are deficiencies in the structural design and construction method; for CN 208347787 U, "A Roadway Reservation Device" and CN 108612544 B, "A Roadway Reservation Device and a Method for Reserving Roadways", their structures and materials both use straight cylindrical arch forms and arch body components. The arch form is made of flexible waterproof materials with a hollow interlayer inside, and liquid or gas can be injected. The construction process for both is to transport the arch form to the construction site, install the arch body components, apply a release agent, tie and fix ropes, inject liquid or gas, fill with mortar, and remove the arch form and arch body components after curing. Their functions and purposes are to replace the traditional method of reserving roadways in the goaf, reduce labor intensity, improve construction efficiency, and reduce construction costs. There are deficiencies in the structure and construction method; for CN 112505299 A, "A Novel Similar Material Simulation Test Roadway Reservation Device with Multiple Sizes", its structure and materials use a horizontal bottom plate, a left arc plate, a right arc plate, a semi-cylindrical top plate, and umbrella-shaped support members, which are composed of steel and threaded components. The construction process is for indoor simulation tests, and a roadway model is formed by assembling the bottom plate, arc plates, and top plate. Its function and purpose are for indoor simulation tests to study the mechanical phenomena in mine exploitation and provide test data. There are deficiencies in the structural design, material use, and construction method; for CN 216617577 U, "A Roadway Reservation Device for Underground Cemented Backfilling", its structure and materials use a wire cage, a sand and gravel layer, and a permeable layer. The sand and gravel layer is filled inside the wire cage, and the permeable layer is located between the sand and gravel 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 detachable retaining wall monomers, and a reserved roadway is formed after backfilling operations. Its function and purpose are to solve the stability problem of the reserved roadway during underground cemented backfilling, prevent the leakage of filling slurry, and ensure the capping rate and the stability of the filling body. There are deficiencies in the structural design and construction method;

[0004] In summary, the above patents all have deficiencies or areas that need improvement in terms of structural design, material use, construction steps, and functional purposes.

[0005] Therefore, it is of great significance to develop a roadway forming method for an empty area filling pre-buried water filtration structure that can improve construction efficiency, reduce construction costs, and ensure operation safety. Summary of the Invention

[0006] The task of the present invention is to overcome the deficiencies of the prior art and provide a roadway forming method for an empty area filling pre-buried water filtration structure, which can not only improve construction efficiency, reduce construction costs, but also ensure operation safety.

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

[0008] For the roadway forming method of the empty area filling pre-buried water filtration structure, aiming at the problems of high cost, low construction efficiency, and poor safety conditions in the reverse excavation roadway in the filling body, as well as the buoyancy effect and impact damage of falling rocks caused by the presence of water in the conventional empty area reserved roadway, especially when most of the pre-buried structures or devices are made of lightweight materials, they are extremely prone to floating and causing the failure of the reserved roadway. First, a water filtration steel structure + double filter cloth 3 is arranged in the empty area (14), which can secrete the excess water in the filling slurry and offset most of the hydraulic pressure of the filling slurry outside the structure for high-strength cementitious filling treatment. In the empty area 14, resist and squeeze the filling slurry or filling body to form a roadway space to obtain a roadway project with the required size and pre-support combined with a steel structure + flexible net. The water filtration steel structure that can filter water and has a certain rigidity is arranged at the bottom of the empty area 14 to pre-form a roadway occupancy space, and the outer geotextile can secrete excess water. The specific process steps and conditions are as follows:

[0009] A. Level the bottom of the empty area. Use a remote-controlled load-haul-dump truck to level the residual ore, waste rock, etc. at the bottom of the empty area 14 to facilitate the transportation and fixation of the structure.

[0010] B. Weld the structure base. Use 2 longitudinal channel steels with a spacing of 3.8 m and 3 upper transverse channel steels with a spacing of 3.8 m and a spacing of 1 m to weld into a base.

[0011] C. Manufacture the water filtration steel structure. First, use steel bars to make multiple frames in the shape of a roadway from bottom to top, and then use longitudinal bars and the base to weld these frames with a vertical and horizontal spacing of 1 m into a water filtration steel structure. The two ends of the water filtration steel structure are welded with 3 horizontal and vertical steel bars each to form a steel arch 8 in the shape of a roadway. Then, use a flexible net 2 and a double-layer filter cloth 3 to wrap the top, surrounding, and two ends of the steel arch 8 respectively to form a water filtration steel structure with a length of about 3 m.

[0012] D. Shipping and layout. Use a remote-controlled load-haul-dump truck 12 to enter the empty area 14, and tow the water filtration steel structure with a steel wire rope 11 at the tail end. Then, manufacture the water filtration steel structure inside the roadway, and successively complete the manufacture, welding, and shipping of each subsequent section of the structure until all the water filtration steel structures in the empty area 14 are arranged.

[0013] E. Empty area staged filling and structural water filtration. Build a filling retaining wall near the roadway opening connected to the empty area 14, and fill the empty area 14 with filling slurry. Limited by factors such as the hydraulic pressure of the filling slurry, the bearing capacity of the filter cloth and the steel frame structure, it needs to be filled in multiple stages: when the 1st - 4th filling reaches the balance of buoyancy and hydraulic pressure, the allowable filling heights are 0.3m, 0.6m, 1.0m, and 2.0m respectively. After the 4th filling height reaches 3.9m, the filling body has basically buried the water - filtering steel structure. At this time, open the drain valve, and the outer - covered geotextile will drain the water secreted from the water - filtering steel structure into the roadway. Then, the 5th large - scale filling is carried out;

[0014] F. Demolish the filling retaining wall and roadway forming. After the filling body in the empty area is cured for about 28 days or reaches a certain strength, demolish the filling retaining wall, as well as the steel bars, flexible nets, and filter cloth at both ends of each section of the water - filtering steel structure, and obtain a roadway jointly supported by the water - filtering steel structure + flexible net.

[0015] Compared with the prior art, the present invention has the following advantages or effects:

[0016] Because the filter cloth is used to secrete the excess water of the filling slurry into the steel structure, alleviating the buoyancy and hydraulic pressure hazards of the filling slurry, the stability of the structure during the empty - area filling process is ensured; at the same time, due to the adoption of the pre - support structure of steel arch frame + flexible net, during the process of forming the roadway in the filling body, the support work of the roadway in the filling body is completed in advance, so the construction efficiency is improved and the construction cost is reduced; in addition, since personnel do not need to enter the empty area, the operation safety can be guaranteed.

[0017] In summary, the present invention realizes high - efficiency, low - cost and safe operation of roadway engineering construction during empty - area filling. It is expected that the construction cost of the roadway in the filling body can be reduced by more than 40%, and the construction efficiency of the roadway in the filling body can be increased by 40 - 100%.

[0018] The innovation points of the present invention are as follows:

[0019] (1) By pre - arranging a water - filtering steel structure in the empty area;

[0020] (2) Carry out high - strength cemented filling treatment on the empty area, use the filter cloth to secrete the excess water of the filling slurry and offset most of the hydraulic pressure of the filling slurry outside the structure;

[0021] (3) Resist and squeeze the filling slurry or filling body in the empty area to form a roadway space. Even if rock falls occur in the empty area, the steel frame structure can effectively resist the damage. After the filling body is cured, finally obtain a roadway project with the required size and jointly pre - supported by the steel frame structure + flexible net;

[0022] (4) Arrange a water - filtering steel structure that can filter water and has a certain rigidity at the bottom of the empty area, pre - forming a roadway occupancy space. The production materials of this water - filtering steel structure are relatively common and the production cost is low;

[0023] (5) The outer geotextile can secrete excess water and resist the hydraulic influence of the filling slurry;

[0024] (6) The use of a water-filtering steel structure + flexible net realizes pre-support, eliminating the need for conventional reverse excavation and support work for roadway engineering in the filling body. Description of the Drawings

[0025] Figure 1 It is a schematic cross-sectional view of the water-filtering structure of a roadway forming method for an empty area filling pre-buried water-filtering structure proposed according to the present invention.

[0026] Figure 2 is Figure 1 The schematic front view of the end of the water-filtering steel structure of the roadway forming method for the empty area filling pre-buried water-filtering structure shown.

[0027] Figure 3 is Figure 2 The schematic side view of the water-filtering steel structure of the roadway forming method for the empty area filling pre-buried water-filtering structure shown.

[0028] Figure 4 is Figure 2 The schematic transportation view of the water-filtering steel structure in the empty area of the roadway forming method for the empty area filling pre-buried water-filtering structure shown.

[0029] Figure 5 is Figure 1 The schematic cross-sectional view of the reserved roadway of the water-filtering steel structure after the empty area filling of the roadway forming method for the empty area filling pre-buried water-filtering structure shown.

[0030] Each label in the drawings respectively represents:

[0031] 1. Water-filtering steel structure 2. Flexible net 3. Double-layer filter cloth 4. Longitudinal reinforcement 5. Water-filtering pipe 6. Vertical reinforcement 7. Horizontal reinforcement 8. Steel arch 9. Universal wheel 10. Water-filtering structure 11. Steel wire rope 12. Remote-controlled load-haul-dump truck 13. Roadway 14. Empty area 15. Ore body.

[0032] The present invention will be further described in detail below with reference to the drawings. Detailed Embodiment

[0033] As shown in the appendix Figures 1 to 5As shown in the figure, a roadway forming method for a pre-buried water filtration structure in an empty area filling. Aiming at the problems of high cost, low construction efficiency, and poor safety conditions in the roadway driven reverse in the filling body, as well as the buoyancy effect and impact damage of falling rocks caused by the presence of water in the filling slurry during the conventional roadway reserved in the empty area. Especially when the pre-buried structure or device is mostly made of lightweight materials, it is very easy to float and cause the failure of the reserved roadway. First, a water filtration steel structure + double filter cloth 3 is arranged in the empty area 14, which can secrete the excess water in the filling slurry and offset most of the hydraulic pressure of the filling slurry outside the structure for high-strength cementitious filling treatment. Resist and squeeze the filling slurry or filling body in the empty area 14 to form a roadway space to obtain a roadway project with the required size and pre-support combined with a steel structure + flexible net. The water filtration steel structure that can filter water and has a certain rigidity is arranged at the bottom of the empty area 14 to form a roadway occupancy space in advance. The outer geotextile can secrete excess water. The specific process steps and conditions are as follows:

[0034] A. Level the bottom of the empty area. Use a remote-controlled load-haul-dump truck to level the residual ore, waste rock, etc. at the bottom of the empty area 14 to facilitate the transportation and fixation of the structure;

[0035] B. Weld the structure base. Weld a base with 2 longitudinal channel steels with a spacing of 3.8m and 3 upper transverse channel steels with a spacing of 3.8m and a spacing of 1m between them;

[0036] C. Manufacture the water filtration steel structure. First, use steel bars to make multiple frames in the shape of a roadway from bottom to top, and then weld these frames into a water filtration steel structure with a longitudinal and transverse spacing of 1m using longitudinal bars and the base. At both ends of the water filtration steel structure, weld 3 steel bars each for the transverse bars 7 and longitudinal bars 4 to form a steel arch 8 in the shape of a roadway. Then, wrap the top, surrounding, and both ends of the steel arch 8 with a flexible net 2 and a double-layer filter cloth 3 respectively to form a water filtration steel structure with a length of about 3m;

[0037] D. Shipping and layout. Use a remote-controlled load-haul-dump truck 12 to enter the empty area 14, and tow the water filtration steel structure with a steel wire rope 11 at the tail end. Then, manufacture the water filtration steel structure inside the roadway, and successively complete the manufacture, welding, and shipping of each subsequent section of the structure until all the water filtration steel structures in the empty area 14 are arranged;

[0038] E. Subdivided filling of the empty area and water filtration of the structure. Build a filling retaining wall near the roadway entrance connected to the empty area 14, and fill the empty area 14 with filling slurry. Limited by factors such as the hydraulic pressure of the filling slurry, the pressure-bearing capacity of the filter cloth and steel frame structure, etc., it needs to be filled in multiple times: the allowable filling heights when the buoyancy and hydraulic pressure are balanced for the 1st - 4th fillings are 0.3m, 0.6m, 1.0m, and 2.0m respectively. After the filling height of the 4th filling reaches 3.9m, the filling body has basically buried the water filtration steel structure. At this time, open the drain valve, and the outer geotextile drains the water filtered out from the water filtration steel structure into the roadway. Then, conduct a large-scale filling for the 5th time;

[0039] F. Demolish the filling retaining wall and form the roadway. After the filling body in the goaf is cured for about 28 days or reaches a certain strength, demolish the filling retaining wall, as well as the steel bars, flexible nets, and filter cloth at both ends of each section of the water-filtering steel structure framework, to obtain a roadway jointly supported by the water-filtering steel structure framework + flexible net.

[0040] The system of the present invention can further be:

[0041] Install universal wheels 9 at the bottom of the longitudinal channel steel of the water-filtering structure base in step B.

[0042] In step C, the length: width: height of the roadway-shaped framework = 3m: 3.8m: 3.8m.

[0043] In step C, the length × width of the flexible net 2 = 10 - 12m: 3m, the wire diameter of the mesh is 4mm, and the mesh size is 80mm.

[0044] In step C, the length: width: height of the water-filtering structure 10 = 3m: 3.8m: 3.8m.

[0045] In step C, the length: width: height of the water-filtering steel structure framework 8 = 3m: 3.8m: 3.8m.

[0046] 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. The roadway forming method of the pre-buried water filtration structure for gob filling. Aiming at the problems of high cost, low construction efficiency and poor safety conditions in the roadway driven reverse in the filling body, as well as the buoyancy effect and impact damage of falling rocks caused by the presence of water in the filling slurry during the conventional gob reserved roadway process, especially when the pre-buried structure or device is mostly made of lightweight materials, it is very easy to float and cause the failure of the reserved roadway, the characteristics are as follows Pre-lay a water-filtering steel structure + double filter cloth (3) in the empty area (14), which can secrete the excess water in the filling slurry and offset most of the hydraulic pressure of the filling slurry outside the structure for high-strength cemented filling treatment. Resist and squeeze the filling slurry or filling body in the empty area (14) to form a roadway space, and obtain a roadway project jointly pre-supported by a steel structure + flexible net with the required size. Lay a water-filtering steel structure that can filter water and has a certain rigidity at the bottom of the empty area (14) to pre-form a roadway occupancy space. The outer geotextile can secrete excess water. The specific process steps and conditions are as follows: A. Level the bottom of the empty area. Use a remote-controlled scraper to level the residual ore, waste rock, etc. at the bottom of the empty area (14) to facilitate the transportation and fixation of the structure. B. Weld the structure base. Use 2 longitudinal channel steels with a spacing of 3.8 m and 3 upper transverse channel steels with a spacing of 3.8 m and a spacing of 1 m to weld into a base. C. Manufacture the water-filtering steel structure. First, use steel bars to make multiple frames in the shape of a roadway from bottom to top, and then use longitudinal bars (4) and the base to weld these frames into a water-filtering steel structure with a longitudinal and transverse spacing of 1 m. At both ends of the water-filtering steel structure, use 3 steel bars each for horizontal bars (7) and vertical bars (4) to weld to form a steel arch frame (8) in the shape of a roadway. Then, use a flexible net (2) and a double-layer filter cloth (3) to wrap the top, surrounding, and both ends of the steel arch frame (8) respectively to form a water-filtering steel structure (10) with a length of about 3 m. D. Consign and arrange. Use a remote-controlled scraper (12) to enter the empty area (14), and use the steel wire rope (11) towed at the tail end to consign the water-filtering steel structure. Then, manufacture the water-filtering steel structure inside the roadway, and successively complete the manufacture, welding, and consignment of each subsequent section of the structure until all the water-filtering steel structures in the empty area (14) are arranged. E. Fill the empty area in batches and filter water through the structure. Build a filling retaining wall near the roadway entrance connected to the empty area (14), and fill the empty area (14) with filling slurry. Limited by factors such as the hydraulic pressure of the filling slurry, the pressure-bearing capacity of the filter cloth and the steel structure, it needs to be filled in batches: when the buoyancy and hydraulic pressure are balanced for the 1st - 4th filling, the allowable filling heights are 0.3 m, 0.6 m, 1.0 m, and 2.0 m respectively. After the filling height of the 4th filling reaches 3.9 m, the filling body has basically buried the water-filtering steel structure. At this time, open the valve of the drain pipe, and the outer geotextile will drain the water secreted from the water-filtering steel structure into the roadway. Then, carry out large-scale filling for the 5th time. F. Demolish the filling retaining wall and form the roadway. After the filling body in the empty area is cured for about 28 days or reaches a certain strength, demolish the filling retaining wall and the steel bars, flexible net, and filter cloth at both ends of each section of the water-filtering steel structure to obtain a roadway jointly supported by a water-filtering steel structure + flexible net.

2. The method according to claim 1, characterized in that Install universal wheels (9) at the bottom of the longitudinal channel steel of the water-filtering structure base in step B.

3. The method according to claim 1, wherein In step C, the length: width: height of the frame in the shape of a roadway is 3 m: 3.8 m: 3.8 m.

4. The method according to claim 1, characterized in that In step C, the length × width of the flexible net (2) is 10 - 12 m: 3 m, the wire diameter of the mesh is 4 mm, and the mesh size is 80 mm.

5. The method according to claim 1, characterized in that In step C, the length: width: height of the water-filtering structure (10) is 3 m: 3.8 m: 3.8 m.

6. The method according to claim 1 or 3 or 4 or 5, characterized in that The length: width: height of the step filter C water filter steel structure (8) is 3m: 3.8m: 3.8m.

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