WO2021120991A1

WO2021120991A1 - Method for reconstructing shield tunnel for mining construction

Info

Publication number: WO2021120991A1
Application number: PCT/CN2020/130990
Authority: WO
Inventors: 罗进海; 贺卫国; 徐宏; 李凯; 王江卡; 邓有春; 许铁力; 付伟; 周鹏; 吕江龙; 田黎明
Original assignee: 中铁一局集团有限公司; 中铁一局集团城市轨道交通工程有限公司
Priority date: 2019-12-16
Filing date: 2020-11-24
Publication date: 2021-06-24
Also published as: CN110985025B; SG11202111608VA; CN110985025A

Abstract

Disclosed is a method for reconstructing a shield tunnel for mining construction. The method comprises the steps of: 1, carrying out construction preparation; 2, abandoning a shell of a shield tunneling machine and disassembling the shield tunneling machine; 3, carrying out horizontal road construction; 4, carrying out protection on a shield tunnel (12), and excavating a transitional section of a mining tunnel (11); 5, forming the transitional section of the mining tunnel (11); and 6, constructing the mining tunnel (11). After construction of the shield tunnel (12) is completed, the shield tunneling machine is subjected to shell abandonment and disassembly in the tunnel, the shield tunneling machine is dismantled and then transported out, a formed shield tunnel transportation system and pipeline arrangement are reconstructed and adjusted, protective measures for the shield tunnel (12) are added and a ring beam is constructed in the transitional section to guarantee inter-zonal safety, and necessary conditions are provided for mining construction, such that mining construction in the shield tunnel is realized, and the problem of it not being possible for a shield to be tunneled due to unforeseen circumstances and a mining method needing to be used to continue construction, or the problem of the construction difficulty of the mining tunnel (11) increasing and a new working face needing to be provided in the shield tunnel are solved, thereby guaranteeing the smooth penetration of an inter-zonal tunnel.

Description

Method for rebuilding shield tunnel for mining method

Technical field

The invention belongs to the technical field of mining method construction in a shield tunnel, and specifically relates to a method for rebuilding a shield tunnel for mining method construction.

Background technique

Tunnel construction methods include shield method, mining method, open-cut method, etc. In the construction process of a certain project or a certain section, one construction method is used alone or multiple construction methods are used in sections. For interval tunnel projects, the mining method and shield method are often used according to the stratigraphic sections of different sections. However, there are many uncertain factors in the construction process of underground engineering. The mining method may be caused by water inrush, sand influx, and stratum changes. Other accidents make the construction more difficult and affect the penetration of the entire interval. Also, due to accidents such as inaccurate stratum surveys and serious damage to equipment, it may also be difficult to continue the construction of shield tunnels. At present, it is common to carry out shield tunnel construction in mining method tunnels. Usually, the shield machine is pushed through the mining method tunnel to the interface to start the shield method construction, but the mining method construction is carried out in the shield tunnel. , There is no effective method yet.

Technical solutions

The technical problem to be solved by the present invention is to provide a method for rebuilding a shield tunnel for mining construction in view of the above-mentioned shortcomings in the prior art. After the construction of the shield tunnel is completed, the shield machine is discarded and dismantled in the tunnel. The machine is disassembled, the shield machine is disassembled and transported out, the formed shield tunnel transportation system and pipeline layout are reconstructed and adjusted, shield tunnel protection measures are added, and ring beams are installed in the transition section to ensure the safety of the section and serve the mine. Method construction provides the necessary conditions to realize the mining method construction in the shield tunnel, and solve the problem that the shield cannot be excavated due to accidents and the mining method needs to be used to continue the construction, or the mining method tunnel construction becomes more difficult, so it needs to be in the shield tunnel. The problem of the newly opened working face in the interior, so as to ensure the smooth passage of the interval tunnel, which is convenient for promotion and use.

In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for rebuilding a shield tunnel for mining method construction, characterized in that the method includes the following steps:

Step 1. Preparation for construction. After the shield tunnel is in place, the surrounding rock formations of the shield tunneling machine will be reinforced and waterproofed. The process is as follows:

Step 101: Use a shield machine to fill the shield tail with grease to protect the shield tail brush;

Step 102. After the shield tunnel construction is in place, the last 10 rings of the shield tunnel construction are sealed and grouted, and the double grout is used for the grouting construction. The grouting is carried out by the reserved secondary grouting holes of the pipe segments. Symmetric injection at the top, the grouting pressure is 0.3 bar～0.4bar; and the grouting pressure and segment are monitored during the grouting process to prevent the segment from cracking or misalignment;

Step 103. The last 10 pipe rings constructed by the shield tunnel method are tightened with tension steel plates. A total of 6 to 8 tension steel plates are set in the longitudinal direction of the last 10 pipe rings constructed by the shield method to prevent the segment from being unloaded after penetration. Force loosening

Step 104. Set the carrying steel plate and the curved steel plate on the last pipe ring constructed by the shield method, and weld and seal it with the shield tail of the shield shell, and then block the last pipe ring constructed by the shield method through the reinforcing ribs. The pre-embedded steel plate, arc steel plate and shield shell are fixed and welded in the ring, and micro-expanded cement is injected through the grouting hole of the tube piece to fill the gap between the tube piece and the shield tail of the shield shell;

Step 105. Set a sealing steel plate on the shield head of the shield shell to block the gap between the shield head of the shield shell and the surrounding rock, and inject micro-expansion cement through the radial grouting hole of the middle shield for filling to block the shield body Surrounding formation water;

Step 106: Set up a smoke exhaust fan on the front side of the tunnel excavation to form a convection with the original air supply fan in the tunnel, accelerate the air circulation on the working surface, and ensure the rapid discharge of smoke and dust in the tunnel;

Step 2: Dismantle the shell of the shield machine: follow the order of the supporting trolley, assembling machine and walking beam, H frame, motor, man cabin, propulsion cylinder, stone crusher, cutter head, and main bearing in the cave Dismantle the shell and dismantle the machine for construction. After the supporting trolley is disconnected, pull out the tunnel directly. The assembly machine and walking beam, H frame, motor, human cabin, propulsion cylinder, stone crusher, cutter head and main bearing components are disassembled, After being cut off, they are transported out of the tunnel in blocks, and the discarded shield shells are kept in place;

Step 3. Horizontal road construction: First, pave the molded concrete on the pipe ring of the shield tunnel. The maximum thickness of the molded concrete is 500mm～700mm, and the single-layer steel mesh and connecting steel bars are embedded in the molded concrete; Lay a concrete protective layer on the concrete to protect the single-layer steel mesh, and keep the connecting steel bars upright; then pour the track bed;

Step 4. The protection of shield tunnel and the excavation of the transition section of the mining method tunnel: the transition section of the mining method tunnel is excavated by blasting. Before the transition section of the mining method tunnel is excavated by blasting, at the end of the shield construction A plurality of suspension bolts for hanging the protective curtain are installed on the end surface of a pipe ring, and the suspension bolts are inserted into the side bolt holes of the last section of the pipe ring constructed by the shield tunnel method, and the suspension bolts are used as the hanging point of the curtain. Use steel wire rope net;

Then, the last 3 to 5 pipe rings of the shield construction method are covered with a pipe piece protective layer, the pipe piece protective layer includes a bottom layer of wood board and a protective layer of cotton layer laid on the bottom layer of the wood board;

During the construction of the transition section of the mining method tunnel, the transport vehicle reversed from the shield originating station into the excavation surface, and then left in the direction of the traffic. The shield originating station was used as a vehicle turnaround and temporary storage area for equipment. The muck produced in the transition section of the tunnel is exported;

The length of the transition section of the mining method tunnel is 30m～50m;

Step 5. The process of forming the transition section of the mining method tunnel is as follows:

Step 501. Set a ring beam at one end of the last pipe ring constructed by the shield method near the mining method tunnel. The ring beam is a reinforced concrete structure. The steel bars of the ring beam are prefabricated in the last pipe ring constructed by the shield method. The embedded pre-embedded steel plate is fixedly connected with the plugging reinforcing rib, one end of the ring beam extends beyond the pipe ring and is fixedly connected with the shield shell, and the other end of the ring beam extends 10 cm into the pipe ring;

Step 502, the construction joint between the ring beam and the last pipe ring constructed by the shield method is chipped and the water-expandable water-stop strip and the grouting pipe are set in the construction joint;

Step 503: Perform secondary lining construction on the transition section of the mining method tunnel, construct the secondary lining of the transition section of the mining method tunnel, and simultaneously place the ring beam concrete and the secondary lining concrete pouring, and at the same time, the ring beam is far away from the mine Extend the lining construction on one side of the transition section of the method tunnel to construct the extension lining of the transition section of the mining method tunnel. The extension lining extends into the last 3 to 5 rings of the shield method construction. In addition, the shield shell and the tube The gap between the rings is filled with shield tail grouting, so that the secondary lining, ring beam, extension lining, pipe ring and shield shell are poured into one body;

Step 6. Mining method tunnel construction: The mining method tunnel is excavated by blasting. During the mining method tunnel construction process, the transportation vehicle uses the mining method tunnel as a vehicle turning and equipment storage area to output the newly generated slag from the mining method tunnel. .

The above-mentioned method for rebuilding a shield tunnel for mining construction is characterized in that: in step 501, the embedded steel plate is set in the last pipe ring through anchoring ribs.

The above-mentioned method for rebuilding a shield tunnel for mining method construction is characterized in that: in step 3, the horizontal road construction is carried out while pipeline adjustment is performed until the requirements of the mining method construction are met. The pipeline includes a ventilation pipe, a water supply pipe, and a sewage discharge pipe. Pipes, high-voltage cables, lighting lines, communication lines, aisle board pipelines and transformer pipelines. After the transformer pipelines are removed from the shield machine, they are installed on the side walls of the tube segments through a bolt-laying platform.

The above-mentioned method for rebuilding a shield tunnel for mining construction is characterized in that the mesh diameter of the steel wire rope net in step 4 is 100 mm to 200 mm.

The above-mentioned method for rebuilding a shield tunnel for mining construction is characterized in that the number of suspension bolts in step 4 is 8-10, and 8-10 suspension bolts are evenly arranged in the last ring of the shield construction The end face of the pipe ring.

The above-mentioned method for rebuilding a shield tunnel for mining construction is characterized in that the micro-expansive cement in step 104 is AEC micro-expansive cement.

Beneficial effect

Compared with the prior art, the present invention has the following advantages:

1. The present invention strengthens the surrounding rock formations of the shield tunneling machine after the shield tunnel is constructed in place through construction preparations, and performs waterproofing treatment, and performs strict groundwater plugging of the tail section of the shield tunneling machine with micro-expansive cement, and micro-expansive cement At the same time, it can achieve the role of strengthening the shield. In addition, the smoke exhaust fan set in front of the tunnel excavation forms convection with the original air supply fan in the tunnel, which accelerates the air circulation on the working surface, and ensures the rapid discharge of smoke and dust in the tunnel to ensure good The construction environment is easy to promote and use.

2. In the present invention, the dismantling construction of the shell and dismantling machine is carried out in the cave. After the supporting trolley is disconnected, it is directly pulled out of the tunnel, assembling machine and walking beam, H frame, motor, human cabin, propulsion cylinder, stone crusher, The cutter head and main bearing parts are disassembled and cut off and transported out of the tunnel in blocks. The discarded shield shell is kept in place. After the discarded shield shell is used, a secondary lining is applied to the shield shell as a permanent support, which is reliable and stable, and has a good use effect.

3. The method of the present invention has simple steps, and necessary modification and adjustments are made to the formed shield tunnel transportation system and pipeline layout. The vertical transportation system configured for shield tunnel construction can basically meet the needs of mining method construction, and various supporting equipment are installed on the ground. The facilities can be used for mining method construction, adding shield tunnel protection measures and constructing ring beams in the transition section to ensure the safety of the interval and provide necessary conditions for the mining method construction, so as to realize the mining method construction in the shield tunnel and solve the accident Circumstances lead to the problem that the shield cannot be tunneled and the mining method must be used to continue the construction, or the mining method tunnel construction becomes more difficult, and the new working face needs to be opened in the shield tunnel to ensure the smooth passage of the interval tunnel.

4. The present invention uses the mining method and shield method to construct the interval tunnel project respectively, broadens the use range of the undercut method, and ensures the smooth passage of the interval. For complex interval tunnel engineering, new construction options are provided. The methods and ideas of the mining method make full use of the facilities and equipment of the original shield method during construction, thereby reducing investment and reducing construction costs.

In summary, after the construction of the shield tunnel of the present invention is completed, the shield machine is dismantled and dismantled in the tunnel, and the shield machine is disassembled and transported out, and the formed shield tunnel transportation system and pipeline are arranged Carry out reconstruction and adjustments, increase shield tunnel protection measures and implement ring beams in the transition section to ensure the safety of the interval, and provide necessary conditions for the mining method construction, so as to realize the mining method construction in the shield tunnel and solve the shield caused by accidents. If the tunnel cannot be tunneled, the mining method needs to be used to continue construction, or the mining method tunnel construction becomes more difficult, and the new working face needs to be opened in the shield tunnel, so as to ensure the smooth passage of the interval tunnel and facilitate the promotion and use.

The technical solutions of the present invention will be further described in detail below through the accompanying drawings and embodiments.

Description of the drawings

Fig. 1 is a schematic diagram of the reinforced structure of the shield shell of the shield machine of the present invention after the shell is abandoned and disassembled.

Figure 2 is a schematic structural diagram of the horizontal road construction of the present invention.

Fig. 3 is a schematic diagram of the positional relationship between the mining method tunnel, the shield method tunnel and the shield starting station of the present invention.

Figure 4 is a schematic diagram of the installation of the protective door curtain and the segment protection layer of the present invention on the shield tunnel.

Figure 5 is a schematic diagram of the installation relationship between the protective door curtain and the pipe ring of the present invention.

Figure 6 is a schematic diagram of the positional relationship between the shield shell, the pipe ring, the ring beam, the extension lining and the secondary lining of the present invention.

Fig. 7 is a schematic diagram of the installation relationship of the ring beam, the embedded steel plate and the pipe ring of the present invention.

Fig. 8 is a method flow block diagram of the method of the present invention.

Description of reference signs:

1—岩层；1—Rock formation;	2—盾壳；2—Shield shell;	3—封堵钢板；3—Block the steel plate;
4—管环；4—pipe ring;	5—拉紧管板；5—Tighten the tube sheet;	6—封堵加强筋；6—Blocking reinforcement ribs;
7—模筑混凝土；7—Molding concrete;	8—联系钢筋；8—Connect the steel bars;	9—混凝土保护层；9—Concrete protective layer;
10—道床；10-track bed;	11—矿山法隧道；11—Mining method tunnel;	12—盾构法隧道；12—Shield tunneling;
13—盾构始发站；13—The shield originating station;	14—防护门帘；14—Protective door curtain;	15—悬挂螺栓；15—Hanging bolts;
16—管片保护层；16—Segment protection layer;	17—圈梁；17—Ring beam;	18—延伸衬砌；18—Extension lining;
19—二次衬砌；19—Secondary lining;	20—预埋钢板；20—Pre-embedded steel plate;	21—锚固筋。21—Anchor reinforcement.

Embodiments of the present invention

As shown in Fig. 1 to Fig. 8, a method for rebuilding a shield tunnel for mining construction according to the present invention includes the following steps:

Step 1. Construction preparation. After the shield tunnel 12 is constructed in place, the surrounding rock layer 1 of the shield machine is reinforced and waterproofed. The process is as follows:

Step 102. After the construction of the shield tunnel 12 is in place, the last 10 rings of the shield tunnel 4 are sealed and grouted, and the double grout is used for the grouting construction. The grouting uses the segment to reserve secondary grouting holes Symmetrical injection from bottom to top, the grouting pressure is 0.3 bar～0.4bar; and during the grouting process, the grouting pressure and segment are monitored to prevent the segment from cracking or misalignment;

Step 103. The last 10 ring pipe rings 4 constructed by the shield tunnel method are tightened by the tension steel plate 5. The last 10 ring pipe rings 4 constructed by the shield method are set with 6 to 8 tension steel plates 5 in the longitudinal direction to prevent penetration The unloading force of the rear segment is loose;

Step 104. Set the back steel plate and the curved steel plate on the last pipe ring 4 of the shield construction method, and weld and seal it with the shield tail of the shield shell 2, and then block the reinforcing rib 6 to make the final shield construction The pre-embedded steel plate, arc-shaped steel plate and the shield shell 2 are fixed and welded in the tube ring 4, and micro-expanded cement is injected through the tube grouting hole to fill the gap between the tube sheet and the shield tail of the shield shell 2;

In this embodiment, the micro-expansion cement mentioned in step 104 is AEC micro-expansion cement, a hydraulic cementing material that compensates for the shrinkage of concrete, with good crack resistance, good impermeability, low alkali, low heat of hydration, and strength performance. High, good bonding performance, good corrosion resistance, slight expansion and compensation for shrinkage.

Step 105. Set a sealing steel plate 3 on the shield head of the shield shell 2 to seal the gap between the shield head of the shield shell 2 and the surrounding rock, and inject micro-expansion cement through the radial grouting hole of the middle shield for filling, sealing Block the formation water around the shield body;

It should be noted that after the construction of the shield tunnel is in place, the surrounding rock formations of the shield machine shall be reinforced and waterproofed, and the tail section of the shield machine shall be strictly blocked by micro-expansive cement with groundwater and slightly expanded. The cement can also achieve the role of strengthening the shield. In addition, the smoke exhaust fan set in front of the tunnel excavation forms convection with the original air supply fan in the tunnel, which accelerates the air circulation on the working surface, and ensures the rapid discharge of smoke and dust in the tunnel to ensure good quality Construction environment.

Step 2: Dismantle the shell of the shield machine: follow the order of the supporting trolley, assembling machine and walking beam, H frame, motor, man cabin, propulsion cylinder, stone crusher, cutter head, and main bearing in the cave Dismantle the shell and dismantle the machine for construction. After the supporting trolley is disconnected, pull out the tunnel directly. The assembly machine and walking beam, H frame, motor, human cabin, propulsion cylinder, stone crusher, cutter head and main bearing components are disassembled, After being cut off, they are transported out of the tunnel in blocks, and the discarded shield shell 2 is kept in place;

It should be noted that the dismantling of the shell and dismantling machine is carried out in the cave, and the supporting trolley is disconnected and pulled out of the tunnel directly, assembling the machine and walking beam, H frame, motor, man silo, propulsion cylinder, and stone crusher. , The cutter head and the main bearing components are disassembled and cut off and transported out of the tunnel in pieces. The discarded shield shell is kept in place. After the discarded shield shell, a secondary lining will be used as permanent support in the shield shell, which is reliable and stable, and has good use effect. .

Step 3. Horizontal road construction: First, pave the molded concrete 7 on the pipe ring 4 of the shield tunnel 12, the maximum thickness of the molded concrete 7 is 500mm～700mm, and the single-layer steel mesh and connection are embedded in the molded concrete 7 Rebar 8; Lay a concrete protective layer 9 on the molded concrete 7 to protect the single-layer rebar mesh, and connect the rebar 8 to keep it vertical; then pour the track bed 10;

In this embodiment, during the horizontal road construction in step 3, pipeline adjustments are carried out until the requirements of mining method construction are met. The pipelines include ventilation pipes, water supply pipes, sewage pipes, high-voltage cables, lighting lines, communication lines, and walkway board pipelines. And the transformer pipeline, after the transformer pipeline is disassembled from the shield machine, it is installed on the side wall of the tube segment through a bolt laying platform.

It should be noted that the necessary modification and adjustment of the formed shield tunnel transportation system and pipeline layout. The vertical transportation system configured for the shield tunnel construction can basically meet the needs of mining method construction, and all supporting equipment and facilities can be used on the ground. In the mining method construction, ventilation pipes, water supply pipes, sewage pipes, high-voltage cables, lighting lines, communication lines, and walkway board pipelines basically meet the requirements of the mining method construction, with small adjustments. When the pipelines are laid separately, they can be constructed by the shield method. Pipeline hook.

Step 4. Shield tunnel protection and excavation of the transition section of the mining method tunnel: The transition section of the mining method tunnel 11 is excavated by blasting, and the transition section of the mining method tunnel 11 is excavated by the shield method before the blasting excavation. A number of suspension bolts 15 for suspending the protective curtain 14 are installed on the end surface of the last pipe ring 4, and the suspension bolts 15 penetrate into the side bolt holes of the last pipe ring 4 of the shield tunnel construction, and the suspension bolts 15 are used as The curtain hanging point, the protective curtain 14 adopts steel wire rope net;

In this embodiment, the number of suspension bolts 15 in step 4 is 8-10, and 8-10 suspension bolts 15 are evenly arranged on the end surface of the last pipe ring 4 constructed by the shield method.

In this embodiment, the mesh diameter of the steel wire rope net in step 4 is 100 mm to 200 mm.

Then, the last 3 to 5 rings of the pipe ring 4 constructed by the shield method are covered with a segment protection layer 16, the segment protection layer 16 comprising a bottom layer of wood and a protective layer of cotton layer laid on the bottom of the wood;

It should be noted that the transition section of the mining method tunnel 11 is excavated by blasting, and the phenomenon of flying rocks is inevitable. The protective door curtain 14 is used to block the flying rocks to prevent the flying rocks from damaging the segments. When the muck is transported, the protective door curtain 14 is used. Untie the connection on one side and close the wire rope net to one side to facilitate the passage of people and vehicles.

During the construction of the transition section of the mining method tunnel 11, the transport vehicle reversed from the shield originating station 13 into the excavation surface, and left in the direction of the traffic, using the shield originating station 13 as a vehicle U-turn and temporary storage area for equipment , Output the muck produced in the transition section of the mining method tunnel 11;

The length of the transition section of the mining method tunnel 11 is 30m～50m;

Step 501. Set a ring beam 17 at one end of the last pipe ring 4 of the shield construction method close to the mining method tunnel 11. The ring beam 17 is a reinforced concrete structure, and the steel bars of the ring beam 17 are the same as the last one of the shield construction method. The pre-embedded steel plate 20 embedded in the ring pipe ring 4 is fixedly connected to the plugging reinforcing rib 6; one end of the ring beam 17 extends beyond the pipe ring 4 and is fixedly connected to the shield shell 2, and the other end of the ring beam 17 extends into the pipe ring 10cm within 4;

In this embodiment, in step 501, the embedded steel plate 20 is set in the last pipe ring 4 through the anchor rib 21.

Step 502, the construction joint between the ring beam 17 and the last pipe ring 4 of the shield construction method is chipped and the water-swelling water-stop strip and the grouting pipe are set;

Step 503: Perform secondary lining construction on the transition section of the mining method tunnel 11, construct the secondary lining 19 of the transition section of the mining method tunnel 11, and perform simultaneous pouring of the ring beam 17 concrete pouring and the secondary lining 19 concrete pouring, and at the same time, Perform extension lining construction on the side of the ring beam 17 away from the transition section of the mining method tunnel 11, construct the extension lining 18 of the transition section of the mining method tunnel 11, and extend the extension lining 18 into the last 3 to 5 rings of the shield construction. In the ring 4, in addition, the gap between the shield shell 2 and the tube ring 4 is filled with shield tail grouting, so that the secondary lining 19, the ring beam 17, the extension lining 18, the tube ring 4 and the shield shell 2 are poured into one body;

Step 6. Mining method tunnel construction: The mining method tunnel 11 is excavated by blasting. During the construction process of the mining method tunnel 11, the transportation vehicle uses the mining method tunnel 11 as a vehicle turnaround and equipment storage area, which is newly generated for the mining method tunnel 11. The muck is exported.

When the present invention is used, shield tunnel protection measures are added and ring beams are applied in the transition section to ensure the safety of the interval and provide necessary conditions for the mining method construction, thereby realizing the mining method construction in the shield tunnel and solving the shield caused by accidents. The problem that the tunnel cannot be excavated requires the use of the mining method to continue construction, or the difficulty of the mining method tunnel construction becomes more difficult, and the new working face needs to be opened in the shield tunnel to ensure the smooth passage of the interval tunnel. The mining method and shield are used for the sections respectively. Interval tunnel construction constructed by construction method broadens the use range of undercut method and ensures the smooth passage of the interval. For complex interval tunnel engineering, new methods and ideas are provided in construction selection, and the original shield is fully utilized in mining method construction. Various facilities and equipment during construction method construction, thereby reducing investment and reducing construction costs.

The above are only preferred embodiments of the present invention and do not impose any limitation on the present invention. Any simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still belong to the technology of the present invention. Within the scope of protection of the program.

Claims

A method for rebuilding a shield tunnel for mining construction, characterized in that the method includes the following steps: step one, construction preparation, after the shield tunnel (12) is constructed in place, the surrounding rock formation (1) of the shield machine is performed Reinforce and do waterproof treatment, the process is as follows: Step 101, use a shield machine to fill the shield tail with grease to protect the shield tail brush;

Step 102. After the construction of the shield tunnel (12) is in place, the last 10 rings (4) of the shield tunnel construction are sealed ring grouting, and the double grout is used for grouting construction, and the grouting adopts two reserved pipe segments. The secondary grouting holes are injected symmetrically from bottom to top, and the grouting pressure is 0.3bar～0.4bar; and during the grouting process, the grouting pressure and segment are monitored to prevent the segment from cracking or misalignment;

Step 103. Use the tension steel plate (5) to tighten the last 10 pipe rings (4) constructed by the shield method, and set a total of 6 to 8 pulls in the longitudinal direction of the last 10 pipe rings (4) constructed by the shield method. Tighten the steel plate (5) to prevent loosening of the unloading force of the segment after penetration;

Step 104. Set the carrying steel plate and the curved steel plate on the last pipe ring (4) of the shield construction method, and weld it with the shield tail of the shield shell (2) to seal it, and then block the reinforcement ribs (6) The steel plate, arc steel plate and shield shell (2) are fixed and welded in the last pipe ring (4) constructed by the shield method, and micro-expansion cement is injected through the grouting hole of the pipe piece to fill the pipe piece and the shield shell (2) The gap between the tails of the shield;

Step 105. Set a sealing steel plate (3) on the shield head of the shield shell (2), block the gap between the shield head of the shield shell (2) and the surrounding rock, and inject the microstructure through the radial grouting hole of the middle shield. Filling with expansive cement to block the formation water around the shield;

Step 106: Set up a smoke exhaust fan on the front side of the tunnel excavation to form a convection with the original air supply fan in the tunnel, accelerate the air circulation on the working surface, and ensure the rapid discharge of smoke and dust in the tunnel;

Step 2: Dismantle the shell of the shield machine: follow the order of the supporting trolley, assembling machine and walking beam, H frame, motor, man cabin, propulsion cylinder, stone crusher, cutter head, and main bearing in the cave Dismantle the shell and dismantle the machine for construction. After the supporting trolley is disconnected, pull out the tunnel directly. The assembly machine and walking beam, H frame, motor, human cabin, propulsion cylinder, stone crusher, cutter head and main bearing components are disassembled, After being cut off, they are transported out of the tunnel in blocks, and the discarded shield shell (2) remains in place;

Step 3. Horizontal road construction: First, pave the molded concrete (7) on the pipe ring (4) of the shield tunnel (12). The maximum thickness of the molded concrete (7) is 500mm～700mm, and the molded concrete (7) ) Pre-embedded single-layer steel mesh and connecting steel bars (8); Lay a concrete protective layer (9) to protect the single-layer steel mesh on the molded concrete (7), and keep the connection steel bars (8) vertical; then pour the track bed (10);

Step 4. Shield tunnel protection and excavation of the transition section of the mining method tunnel: the transition section of the mining method tunnel (11) is excavated by blasting. Before the transition section of the mining method tunnel (11) is excavated by blasting, A plurality of suspension bolts (15) for hanging the protective curtain (14) are installed on the end surface of the last pipe ring (4) of the shield construction method, and the suspension bolts (15) penetrate into the last pipe section of the shield construction method. In the side bolt holes of the ring (4), the suspension bolts (15) are used as the hanging point of the curtain, and the protective curtain (14) adopts a wire rope net;

Then, the last 3 to 5 pipe rings (4) constructed by the shield method are covered with a pipe piece protective layer (16). The pipe piece protective layer (16) includes a bottom layer of a wooden board and cotton laid on the bottom layer of the wooden board. Layer protection layer

During the construction process of the transition section of the mining method tunnel (11), the transport vehicle reverses from the shield originating station (13) into the excavation surface, and leaves in the direction of the traffic, using the shield originating station (13) as the vehicle U-turn and temporary storage area for equipment to output the muck generated in the transition section of the mining method tunnel (11);

The length of the transition section of the mining method tunnel (11) is 30m～50m; Step 5. Forming the transition section of the mining method tunnel. The process is as follows: Step 501. Set a ring beam at the end of the shield tunnel construction (4) near the end of the mining method tunnel (11)

(17), the ring beam (17) is a reinforced concrete structure, the steel bars of the ring beam (17) and the last pipe ring (4) constructed by the shield method

The pre-embedded steel plate (20) is fixedly connected with the sealing reinforcement rib (6), one end of the ring beam (17) extends beyond the pipe ring (4) and is fixedly connected with the shield shell (2), the ring beam (17) The other end of the tube extends 10cm into the pipe ring (4);

Step 502, in the construction joint between the ring beam (17) and the last pipe ring (4) constructed by the shield tunneling method, chipping is performed and the water-swelling water-stop strip and the grouting pipe are set;

Step 503: Perform secondary lining construction on the transition section of the mining method tunnel (11), construct the secondary lining (19) of the transition section of the mining method tunnel (11), and pour the concrete and the secondary lining of the ring beam (17). 19) Concrete pouring is carried out synchronously, and at the same time, the extension lining construction is carried out on the side of the ring beam (17) away from the transition section of the mining method tunnel (11) to construct the extension lining (18) of the transition section of the mining method tunnel (11) , The extension lining (18) extends into the last 3 to 5 pipe rings (4) of the shield construction method. In addition, the gap between the shield shell (2) and the pipe ring (4) is filled with shield tail grouting , Pouring the secondary lining (19), ring beam (17), extension lining (18), pipe ring (4) and shield shell (2) into one body;

Step 6. Mining method tunnel construction: The mining method tunnel (11) is excavated by blasting. During the construction process of the mining method tunnel (11), the transportation vehicle uses the mining method tunnel (11) as a vehicle U-turn and equipment storage area. The newly generated muck from the French tunnel (11) is output.
A method for rebuilding a shield tunnel for mining method construction according to claim 1, characterized in that:

The embedded steel plate (20) in 501 is arranged in the last pipe ring (4) through anchoring ribs (21).
According to a method for rebuilding a shield tunnel for mining method construction according to claim 1, it is characterized in that: in step 3, the horizontal road construction is carried out while pipeline adjustment is performed until it meets the requirements of mining method construction, and the pipeline includes ventilation Pipes, water supply pipes, sewage pipes, high-voltage cables, lighting lines, communication lines, aisle board pipelines and transformer pipelines. After the transformer pipelines are removed from the shield machine, they are installed on the side walls of the pipe slices through a bolt laying platform.
The method for rebuilding a shield tunnel for mining construction according to claim 1, characterized in that: in step 4, the mesh diameter of the steel wire rope net is 100mm-200mm.
The method for rebuilding a shield tunnel for mining construction according to claim 1, wherein the number of suspension bolts (15) in step 4 is 8-10, and 8-10 suspension bolts (15) It is evenly arranged on the end face of the last pipe ring (4) constructed by the shield tunneling method.
The method for rebuilding a shield tunnel for mining method construction according to claim 1, characterized in that:

The slightly expansive cement mentioned in 104 is AEC slightly expansive cement.