Disposal method for mud burst and water burst collapse of water-rich weathered broken zone of high-altitude tunnel

Abstract

The invention belongs to a treatment method for mud bursting and water bursting collapse of a water-rich weathering fracture zone of a high-altitude tunnel, which comprises the following steps of: temporarily sealing a tunnel face, drilling collapse and water bursting to drain water and relieve pressure, radially grouting and reinforcing a constructed primary support behind a section influenced by water bursting and mud bursting, and performing water bursting and water bursting on the primary support after the section influenced by the water bursting and mud bursting to treat the water bursting and water bursting collapse of the water-rich weathering fracture zone of the tunnel. According to the treatment method, the water-rich weathered broken zone of the high-altitude tunnel is subjected to water-rich weathered broken zone mud bursting and water bursting collapse section treatment, then a probe hole is formed in the front portion to detect the front condition, concrete pumping and grouting are conducted on a collapsed cavity, and finally a temporary support is used for additionally arranging an advanced pipe shed to reinforce the collapse section, so that the high-altitude tunnel water-rich weathered broken zone mud bursting and water bursting collapse section can be effectively treated. According to the method, the tunnel construction can smoothly pass through the mud burst and water burst section of the water-rich weathering fracture zone, the tunnel can be smoothly and timely communicated, the treatment method is simple, efficient, low in economic cost and high in treatment speed, the treatment period is shortened, and meanwhile a large amount of construction cost is saved.

Description

Technical Field

[0001] The invention belongs to a method for treating sudden mud and water gushing and landslide in a water-rich weathered broken zone of a high-altitude tunnel. Background Art

[0002] When tunnel construction is carried out in high-altitude areas, the geographical environment of water-rich weathered and broken zones is often encountered. The main geological type of this geographical environment is strong and medium weathered andesitic tuff, and there are many unfavorable geological features such as water-rich broken zones. When the tunnel construction face enters the water-rich weathered and broken zone, mud and water gushing and landslides often occur. Its characteristics are that there are many water gushing outlets, large water volume and large amount of sediment in the water gushing outlets. If the water is not stopped in time, it can quickly lead to the collapse of the tunnel construction face and the gushing water accompanied by sediment will quickly flood the constructed tunnel, causing casualties and huge property losses. The traditional curtain grouting treatment method for the treatment of mud and water gushing and landslides in the water-rich weathered and broken zones of high-altitude tunnels has ended in failure. This is not only because the traditional curtain grouting treatment method is complicated, slow, has a long treatment period and high construction cost, but also because the curtain grouting cannot form a continuous water-blocking curtain in the geological section where the gushing water and sediment move rapidly, thus failing to deal with the mud and water gushing and landslides in the high-altitude water-rich weathered and broken zones tunnels.

[0003] Therefore, how to effectively and quickly deal with sudden mud and water gushing and landslides in tunnels in high-altitude water-rich weathered and broken zones is an urgent problem that needs to be solved in tunnel construction in high-altitude areas. Summary of the invention

[0004] The purpose of the present invention is to provide a method for treating sudden mud and water gushing and landslides in water-rich weathered and broken zones of high-altitude tunnels, so as to solve the problems raised in the above-mentioned background technology.

[0005] To this end, a method for treating sudden mud and water gushing and landslides in a water-rich weathered and broken zone of a high-altitude tunnel according to the present invention comprises the following steps: (1) Face closure: (a) Use sandbags to block the water outlet of the tunnel face where mud and water burst out. Pre-bury two φ160mm plastic drainage pipes at the blocking opening and use the drainage plastic pipes to drain the water from the water outlet to the sump; (b) Use C25 early-strength anchor mesh sprayed concrete with a thickness of not less than 20 cm, φ8 mm steel mesh, and a mesh of 20×20 cm to seal the tunnel face with sudden mud and water gushing; (2) Reinforce the upper step surface and the slag on the middle step: (a) Reinforce the upper step floor with 6-10cm thick C25 early strength concrete; (b) The slag body on the middle step is reinforced by grouting with a φ42×4mm small grouting pipe. After the small pipe is installed, the end is wrapped with geotextile, and the slag body on the middle step is sealed by grouting. C25 shotcrete is used on the outside of the slag body on the middle step to seal the slag body on the middle step to avoid slurry loss during grouting; (3) Drainage and pressure relief: According to the seepage and dripping conditions of the constructed primary support section, 20m long drainage holes are drilled every 1.2m from the middle of the tunnel face to the top, with a total of 6 holes. The height of the drainage holes is arranged in combination with the height of the down-the-hole drill. The external deviation angle of the holes is controlled at 35° to 40°, and the upward angle of each of the 6 holes is controlled within the range of 10° to 20°. Drainage hoses are connected to each hole to divert the pressure relief water in each hole to the temporary drainage ditch; (4) Primary reinforcement of the tunnel face section affected by mud and water inrush: 2 to 2.5 m behind the tunnel face affected by mud and water inrush is the section affected by mud and water inrush and landslides. Φ42×4 mm steel pipes with a length of 4.0 m, annular spacing of 1.5 m, and longitudinal spacing of 0.6 m are used to reinforce the tunnel wall with grouting to play a role in water blocking and consolidation in the later stage. (5) Treatment of collapsed cavity: Since the scope of collapsed cavity caused by water inrush, mud burst and landslide in the tunnel face is unknown, exploration holes are drilled into the collapsed cavity to detect the collapsed cavity above before tunnel construction, so as to take appropriate measures for targeted treatment, including: (a) Design of exploration holes: drill an exploration hole at an interval of 1m at the arch at the upper end of the mud and water surge along the tunnel face, with a total of at least 5 exploration holes. Drill an exploration hole at an interval of 1m at other locations, with a total of at least 2 exploration holes. The inclined length of the exploration hole is controlled at 10-15m, and the horizontal angle of each exploration hole is 35°-37°. After the exploration holes are completed, insert a Φ108×6mm follower pipe into each exploration hole, one of which is used as an exhaust pipe, with a flange welded at the pipe mouth and connected to the pumping or grouting pipe with a flange. The remaining pipes are used as pumping or grouting pipes; (b) After the exploration hole is drilled, if the detected object is loose body, cement grouting is carried out through each root canal into the loose body, and the cement grouting is carried out hole by hole from the low root canal to the high root canal; or at the same time, Φ42×4mm steel flower pipes with a length of 10-15mm are drilled at a circumferential interval of 1.5m on the tunnel wall of the tunnel face outside the root canal control area to carry out grouting reinforcement of the loose body in the tunnel face; (c) After the exploration holes are drilled, if the exploration holes detect that there is a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through the root canals to fill it. When pumping concrete, it is pumped from the low-position exploration holes first. If the pipe is blocked during the concrete pumping and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled; or at the same time, Φ42×4mm steel flower pipes are drilled at an annular spacing of 1.5m on the tunnel wall of the tunnel face outside the root canal control area. The length of the steel pipe is 10-15mm, and the loose body in the tunnel face is grouting reinforced; (6) Advance large pipe shed construction: 3 I20a I-beam arc-shaped guard arches are set under the initial support 2m behind the landslide face. Φ108×6mm steel pipes are arranged side by side on the guard arches to form a large pipe shed arch. After the orifice pipe is installed, positioned and calibrated correctly, the steel arch frame is tightly wrapped with colored strips of cloth and sealed with C25 shotcrete to ensure that there is no loss or leakage during grouting of the pipe shed. The support thickness is not less than the thickness of the large pipe shed arch plus 4cm.

[0006] (7) When the tunneling construction of the closed grouting reinforcement face is carried out forward to 1 to 1.5 m in front of the closed grouting reinforcement section, a probe hole is drilled forward in the middle and upper parts of the next construction face to detect the collapse cavity above before tunnel construction so as to take appropriate measures for targeted treatment. After the exploration hole is drilled, if the next construction face detected is a loose body or a collapse cavity, repeat steps (4) to (5) until the tunnel construction passes through the water-rich weathered fracture zone of the tunnel; if it is a solid rock mass, normal construction is carried out until the tunnel construction is completed.

[0007] As a further description of the above technical solution: the center step slag body is reinforced by grouting with a φ42×4mm grouting small duct. The grouting small duct is 3.5m long, arranged in a plum blossom shape, and the distance between adjacent grouting small ducts is 1.5m.

[0008] As a further description of the above technical solution: the inner diameter of the drain hole is 133 mm, and the inner diameter of the exploration hole is 133 mm.

[0009] As a further description of the above technical solution: after the exploration hole is drilled, if the detected object is a loose body, cement grouting is performed through each root canal into the loose body, and the cement grouting is performed hole by hole from the low root canal to the high root canal, and also includes, or at the same time, Φ42×4mm steel flower pipes are drilled obliquely forward at a circumferential spacing of 1.5m on the tunnel wall of the face outside the root canal control area, and the angle between each steel flower pipe and the tunnel axis is 15°~20°, and the length of the steel pipe is 10~15mm, to carry out grouting reinforcement of the loose body in the tunnel wall face.

[0010] As a further description of the above technical solution: after the exploration holes are drilled, if the exploration holes detect that there is a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through each root canal to fill it. When pumping concrete, it is pumped from the low-position exploration holes first. If the pipe is blocked during the pumping of concrete and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled. It also includes or is simultaneously provided with Φ42×4mm steel flower pipes obliquely forwardly at an annular spacing of 1.5m on the tunnel wall of the face outside the root canal control area. The angle between each steel flower pipe and the tunnel axis is 15°~20°, and the length of the steel pipe is 10~15mm, and grouting reinforcement is carried out on the collapsed cavity in the tunnel wall face.

[0011] The present invention has the following beneficial effects: 1. The present invention treats the landslide caused by sudden mud and water gushing in the water-rich weathered and broken zone of the tunnel by temporarily closing the heading face, drilling holes to drain and relieve the pressure of the landslide water gushing, radially grouting and reinforcing the constructed primary support behind the section affected by the water gushing and mud gushing, then drilling exploration holes in the front to detect the situation in the front and pumping concrete and grouting in the collapsed cavity, and finally using temporary support to add an advance pipe shed to reinforce the landslide section. This treatment method can effectively treat the landslide section caused by sudden mud and water gushing in the water-rich weathered and broken zone of the high-altitude tunnel, so that the tunnel construction can smoothly pass through the mud and water gushing section in the water-rich weathered and broken zone, and ensure that the tunnel can be smoothly and timely penetrated. The treatment method of the present invention is simple and efficient, has low economic cost, fast treatment speed, shortens the treatment period, and saves a lot of construction costs at the same time.

[0012] 2. The present invention has a wide range of applications and can be used to treat various types of tunnel collapse and water gushing. It has a fast treatment speed for landslides and sudden mud and water gushing in weathered and broken zones. The safe and civilized construction is easy to control and has obvious social benefits, thereby effectively improving the safety and reliability of the construction method.

[0013] 3. The present invention is convenient to construct, does not require large-scale construction machinery, has simple procedures, and is easy to master. The present invention has a good use effect, has the advantages of saving labor and effort during construction, simple construction, fast speed, material saving, high efficiency and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the longitudinal section structure of the present invention for the temporary sealing of the face of the tunnel and the reinforcement treatment of the slag body on the middle step; Figure 2 It is a schematic cross-sectional structure diagram of the present invention for the temporary sealing of the face of the tunnel and the reinforcement treatment of the slag body on the middle step; Figure 3 This is a schematic diagram of the distribution structure of the drainage holes for drainage and pressure relief of the present invention; Figure 4 It is a schematic diagram of the longitudinal section structure of the probe hole distribution of the present invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the probe hole distribution of the present invention; Figure 6 It is a schematic diagram of the steel flower pipe distribution structure when reinforcing the initial support of the tunnel face section affected by sudden mud and water inrush according to the present invention; Figure 7 It is a schematic diagram of the distribution structure of the follower pipes and supporting pipe racks of the present invention. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described in conjunction with specific embodiments below, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work all belong to the protection scope of the present invention. The construction methods in the following embodiments, unless otherwise specified, are all conventional methods. The materials, devices, equipment, etc. used in the following embodiments, unless otherwise specified, can all be obtained from commercial channels.

[0016] Example 1: The construction site of the present invention is TJSG-1 section of the G4218 Kunsha Airport Highway Project, with a total length of 5.8km. The Chelarezba Tunnel in the section is 2935m long, and the tunnel face construction adopts a three-step excavation method with 12 lower steps, 10 middle steps and 8 upper steps. The main geological type of the Chelarezba Tunnel in this section is strongly medium-weathered andesitic tuff, and there are many unfavorable geological conditions such as water-rich broken zones. When the construction site reached the upper step of the K20+190 face, mud and water gushing and landslides occurred. The present invention adopts the following method to efficiently complete the treatment of mud and water gushing and landslides, successfully passing through this section of unfavorable geology, and the application effect is good.

[0017] like Figures 1 to 7 As shown, a method for handling sudden mud and water gushing and landslides in a water-rich weathered and broken zone of a high-altitude tunnel comprises the following steps: (1) If Figure 1 , 2 As shown, the tunnel face is closed: During the construction of tunnel 9 to K20+190, the tunnel face of upper step 8 entered the water-rich weathered fracture zone layer 1. Mud and water gushing and landslides occurred during the construction. The mud and water gushing and landslides were located in the middle of the right side of the tunnel face of upper step 8, at the gushing point 2. At the peak, the water gushing volume was about 330m per hour. 3 , the collapse gradually expanded from the right to the left. Immediately, each water outlet position 13 of the face where mud and water burst out was sealed with 4 sandbags. Two φ160mm drainage plastic pipes 14 were pre-buried at the sealing port, that is, one end of the drainage plastic pipe 14 was located at the sealing port and the other end was located at the sump. The drainage plastic pipe was used to drain the gushing water at the water outlet position to the sump. For the entire face of the upper step 8, a C25 early-strength anchor mesh sprayed concrete with a thickness of not less than 20cm was used, in which a layer of φ8mm steel mesh with a mesh of 20×20cm was laid, and the face where mud and water burst out was sealed with 2 layers of early-strength anchor mesh sprayed concrete. The sealing of the face was carried out from the right side of the mud and water burst out and the collapse to the left side and from the bottom to the top quickly.

[0018] (2) Reinforcement of the upper step ground 3 and the middle step slag: To ensure the stability of the upper step enclosure, the pipe shed guide frame and the construction collapse cavity exploration hole have a more stable support surface, and the upper step ground 3 is reinforced with 6-10 cm thick C25 early strength concrete. The slag of the middle step 10 is reinforced with grouting using a φ42×4mm grouting small pipe 5. After the small pipe is installed, the end is wrapped with geotextile and grouting is used to seal the slag of the middle step. The grouting small pipe of φ42×4mm is used for grouting reinforcement. The grouting small pipe is 3.5m long and arranged in a plum blossom shape. The distance between adjacent grouting small pipes is 1.5m. C25 sprayed concrete is used to seal the slag of the middle step on the outside of the slag of the middle step, with a thickness of 6-10cm, to form a concrete sealing layer 11 of the slag of the middle step to prevent the loss of slurry during grouting.

[0019] (3) If Figure 3 As shown, drainage and pressure relief: according to the seepage and dripping conditions of the constructed initial support section 7, 20m long drainage holes 15 are drilled every 1.2m from the middle of the upper step face to the rear top. The inner diameter of the drainage holes is 133mm, and a total of 6 holes are drilled. The drainage holes are arranged at a height combined with the down-the-hole drilling height. The outer deviation angle of the holes is controlled at 35°~40°, and the upward angle of each of the 6 holes is controlled in the range of 10°~20°. Drainage hoses are connected to each hole to divert the pressure relief water in each hole to the temporary drainage ditch.

[0020] (4) If Figure 6 As shown in the figure, the primary support section of the tunnel face affected by mud and water gushing is reinforced: 2 to 2.5 m behind the tunnel face affected by mud and water gushing is the primary support treatment section affected by water gushing, mud and landslide. Φ42×4mm steel flower pipe 19 is used, with a length of 4.0 m, annular spacing of 1.5 m, and longitudinal spacing of 0.6 m. Grouting reinforcement is carried out on the tunnel wall to play the role of later water blocking and consolidation of the tunnel primary support. The scope of primary support reinforcement includes the primary support section of the tunnel face of the upper, middle and lower steps.

[0021] (5) Figure 4 , 5 As shown in the figure, treatment of collapsed cavity: Since the scope of collapsed cavity caused by water gushing, mud bursting and landslide in the tunnel face is unknown, exploration holes are drilled into the collapsed cavity to detect the collapsed cavity above before tunnel construction, so as to take corresponding measures for targeted treatment, including: (a) Design of exploration holes: drill an exploration hole at an interval of 1m in the horizontal direction at the arch at the upper end of the mud and water surge along the tunnel face, with an inner diameter of 133mm. A total of at least 5 exploration holes are drilled. Drill an exploration hole at an interval of 1m at other locations, with a total of at least 2 exploration holes. The inclined length of the exploration hole is controlled at 10-15m, and the horizontal angle of each exploration hole is 35°-37°. After the exploration holes are drilled, insert a Φ108×6mm pipe 16 into each exploration hole, one of which is used as an exhaust pipe, with a flange welded at the pipe mouth and connected to the pumping or grouting pipe by a flange. The remaining pipes are used as pumping or grouting pipes; (b) After the exploration hole is drilled, if the object to be explored is loose body, cement grouting is carried out through each root canal into the loose body. The cement grouting is carried out hole by hole from the lower root canal to the higher root canal, so that the loose body before the tunnel is fixed to be similar to the normal rock layer 6, thereby ensuring the normal excavation of the tunnel.

[0022] (c) After the exploration hole is drilled, if the exploration hole detects a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through various pipes to fill it. When pumping concrete, it is pumped from the low-position exploration hole first. If the pipe is blocked during the concrete pumping and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled, so as to fix the collapsed cavity in front of the tunnel to be similar to the normal rock layer 6, thereby ensuring the normal excavation construction of the tunnel.

[0023] (6) Figure 7 As shown, the construction of the advance large pipe shed 18 is as follows: 3 I20a I-beam arc-shaped guard arches 17 are set under the initial support 2m behind the collapsed heading face, and Φ108×6mm steel pipes are arranged side by side on the guard arch to form a large pipe shed arch. After the orifice pipe is installed, positioned and calibrated correctly, the steel arch frame is tightly wrapped with colored strips of cloth, and C25 shotcrete is used for overall sealing to ensure that there is no loss or leakage during grouting of the pipe shed. The sealing thickness of C25 shotcrete is not less than the thickness of the large pipe shed arch plus 4cm. Finally, the I-beam guard arch and the top large pipe shed are driven into the secondary lining of the tunnel.

[0024] (7) When the tunneling construction of the closed grouting reinforcement face is carried out forward to 1 to 1.5 m in front of the closed grouting reinforcement section, a probe hole is drilled forward in the middle and upper parts of the next construction face to detect the collapse cavity above before tunnel construction so as to take appropriate measures for targeted treatment. After the exploration hole is drilled, if the next construction face detected is a loose body or a collapse cavity, repeat steps (4) to (5) until the tunnel construction passes through the water-rich weathered fracture zone of the tunnel; if it is a solid rock mass, normal construction is carried out until the tunnel construction is completed.

[0025] Embodiment 2: The difference from Embodiment 1 is that in step (5) of Embodiment 1, after drilling the exploration holes in the tunnel face, if the detected object is loose body, cement grouting is performed through each root canal into the loose body, and the cement grouting is performed hole by hole from the low root canal to the high root canal. At the same time, Φ42×4mm steel flower tubes are drilled obliquely forward at an annular spacing of 1.5m on the tunnel wall of the tunnel face outside the root canal control area. The angle between each steel flower tube and the tunnel axis is 15° to 20°, and the length of the steel tube is 10 to 15mm. Grouting reinforcement is performed on the loose body in the tunnel face to fix the loose body in front of the tunnel to a normal rock layer 6, so as to ensure normal tunnel excavation construction. After the installation, if the exploration hole detects that there is a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through each root pipe to fill it. When pumping concrete, pump it from the low-position exploration hole first. If the pipe is blocked during the pumping of concrete and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled. At the same time, Φ42×4mm steel flower pipes are driven obliquely forward at an annular spacing of 1.5m on the tunnel wall of the heading face outside the root pipe control area. The angle between each steel flower pipe and the tunnel axis is 15°~20°, and the length of the steel pipe is 10~15mm. Grouting reinforcement is carried out on the loose body in the tunnel wall heading face to fix the normal rock layer 6 similar to the collapsed cavity in front of the tunnel to ensure normal tunnel excavation construction.

[0026] The rest is the same as that of Example 1, so it will not be described again.

[0027] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for treating sudden mud and water gushing and landslides in water-rich weathered and broken zones of high-altitude tunnels, characterized in that: The steps include: (1) Face closure: (a) Use sandbags to block the water outlet of the tunnel face where mud and water burst out. Pre-bury two φ160mm plastic drainage pipes at the blocking opening and use the drainage plastic pipes to drain the water from the water outlet to the sump; (b) Use C25 early-strength anchor mesh sprayed concrete with a thickness of not less than 20 cm, φ8 mm steel mesh, and a mesh of 20×20 cm to seal the tunnel face with sudden mud and water gushing; (2) Reinforce the upper step surface and the slag on the middle step: (a) Reinforce the upper step floor with 6-10cm thick C25 early strength concrete; (b) The slag body on the middle step is reinforced by grouting with a φ42×4mm small grouting pipe. After the small pipe is installed, the end is wrapped with geotextile, and the slag body on the middle step is sealed by grouting. C25 shotcrete is used on the outside of the slag body on the middle step to seal the slag body on the middle step to avoid slurry loss during grouting; (3) Drainage and pressure relief: According to the seepage and dripping conditions of the constructed primary support section, 20m long drainage holes are drilled every 1.2m from the middle of the tunnel face to the top, with a total of 6 holes. The height of the drainage holes is arranged in combination with the height of the down-the-hole drill. The external deviation angle of the holes is controlled at 35° to 40°, and the upward angle of each of the 6 holes is controlled within the range of 10° to 20°. Drainage hoses are connected to each hole to divert the pressure relief water in each hole to the temporary drainage ditch; (4) Primary reinforcement of the tunnel face section affected by mud and water inrush: 2 to 2.5 m behind the tunnel face affected by mud and water inrush is the section affected by mud and water inrush and landslides. Φ42×4 mm steel pipes with a length of 4.0 m, annular spacing of 1.5 m, and longitudinal spacing of 0.6 m are used to reinforce the tunnel wall with grouting to play a role in water blocking and consolidation in the later stage. (5) Treatment of collapsed cavity: Since the scope of collapsed cavity caused by water inrush, mud burst and landslide in the tunnel face is unknown, exploration holes are drilled into the collapsed cavity to detect the collapsed cavity above before tunnel construction, so as to take appropriate measures for targeted treatment, including: (a) Design of exploration holes: drill an exploration hole at an interval of 1m at the arch at the upper end of the mud and water surge along the tunnel face, with a total of at least 5 exploration holes. Drill an exploration hole at an interval of 1m at other locations, with a total of at least 2 exploration holes. The inclined length of the exploration hole is controlled at 10-15m, and the horizontal angle of each exploration hole is 35 ° ~37 ° After each exploration hole is completed, a Φ108×6mm pipe is inserted into each exploration hole. One of the pipes is used as an exhaust pipe, and a flange is welded at the pipe mouth. It is connected to the pumping or grouting pipe with a flange. The remaining pipes are used as pumping or grouting pipes; (b) After the exploration hole is drilled, if the detected object is loose body, cement grouting is carried out through each root canal into the loose body, and the cement grouting is carried out hole by hole from the low root canal to the high root canal; or at the same time, Φ42×4mm steel flower pipes with a length of 10-15mm are drilled at a circumferential interval of 1.5m on the tunnel wall of the tunnel face outside the root canal control area to carry out grouting reinforcement of the loose body in the tunnel face; (c) After the exploration holes are drilled, if the exploration holes detect that there is a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through the root canals to fill it. When pumping concrete, it is pumped from the low-position exploration holes first. If the pipe is blocked during the concrete pumping and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled; or at the same time, Φ42×4mm steel flower pipes are drilled at an annular spacing of 1.5m on the tunnel wall of the tunnel face outside the root canal control area. The length of the steel pipe is 10-15mm, and the loose body in the tunnel face is grouting reinforced; (6) Advanced large pipe shed construction: 3 I20a I-beam arc-shaped arch guards are set under the initial support 2m behind the collapsed face. Φ108×6mm steel pipes are placed side by side on the arch guards to form a large pipe shed arch. After the orifice pipe is installed, positioned and calibrated correctly, the steel arch frame is tightly wrapped with colored strips of cloth and sealed with C25 shotcrete to ensure that there is no loss or leakage during grouting of the pipe shed. The support thickness is not less than the thickness of the large pipe shed arch plus 4cm; (7) When the tunneling construction of the closed grouting reinforcement face is carried out forward to 1 to 1.5 m in front of the closed grouting reinforcement section, a probe hole is drilled forward in the middle and upper parts of the next construction face to detect the collapse cavity above before tunnel construction so as to take appropriate measures for targeted treatment. After the exploration hole is drilled, if the next construction face detected is a loose body or a collapse cavity, repeat steps (4) to (5) until the tunnel construction passes through the water-rich weathered fracture zone of the tunnel; if it is a solid rock mass, normal construction is carried out until the tunnel construction is completed.

2. The method for treating sudden mud and water gushing and landslide in water-rich weathered and broken zones of high-altitude tunnels according to claim 1 is characterized by: The centering step slag body is reinforced by grouting with a φ42×4mm small grouting tube. The small grouting tube is 3.5m long, arranged in a plum blossom shape, and the distance between adjacent small grouting tubes is 1.5m.

3. The method for handling sudden mud and water gushing and landslides in water-rich weathered and broken zones of high-altitude tunnels according to claim 1 is characterized by: The inner diameter of the drain hole is 133 mm, and the inner diameter of the exploration hole is 133 mm.

4. The method for handling sudden mud and water gushing and landslides in water-rich weathered and broken zones of high-altitude tunnels according to claim 1 is characterized by: After the exploration holes are drilled, if the detected object is a loose body, cement grouting is performed through each root canal into the loose body. The cement grouting is performed hole by hole from the low-position root canal to the high-position root canal. It also includes or simultaneously drilling Φ42×4mm steel flower pipes obliquely forward at a circumferential spacing of 1.5m on the tunnel wall of the face outside the root canal control area. The angle between each steel flower pipe and the tunnel axis is 15°~20°, and the length of the steel pipe is 10~15mm, to carry out grouting reinforcement of the loose body in the tunnel wall face.

5. The method for handling sudden mud and water gushing and landslides in water-rich weathered and broken zones of high-altitude tunnels according to claim 1 is characterized by: After the exploration holes are drilled, if the exploration holes detect that there is a collapsed cavity in front, C25 concrete is pumped into the collapsed cavity through each root pipe for filling treatment. When pumping concrete, it is first pumped from the low-position exploration holes. If the pipe is blocked during the pumping of concrete and concrete cannot be pumped, other exploration holes are used to continue pumping concrete until the collapsed cavity is filled. It also includes or is simultaneously in the tunnel wall of the face outside the root canal control area, Φ42×4mm steel flower pipes are drilled obliquely forward at an annular spacing of 1.5m. The angle between each steel flower pipe and the tunnel axis is 15°~20°, and the length of the steel pipe is 10~15mm, and grouting reinforcement is carried out on the collapsed cavity in the tunnel wall face.

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