Advanced pipe shed suspension structure construction method for replacing underground excavation temporary support

Abstract

According to the construction method of the advanced pipe shed suspension structure replacing the underground excavation temporary support, the steel pipes with the steel wire ropes are arranged in the pre-buried holes, in the subsequent sectional excavation process, the steel wire ropes are fixed to the tops and the two sides of the first grid steel frame and the second grid steel frame in a sleeving mode and are tightened and limited, and the third grid steel frame is arranged in a downward excavation mode; the three sets of grating steel frames are closed to form a ring to achieve relative limiting, traditional temporary support arrangement is replaced, potential safety hazards are avoided, meanwhile, large mechanical equipment can conveniently enter a tunnel for operation, temporary support dismantling is not needed in the later period, resources and manufacturing cost are saved, risks are reduced, unnecessary support construction is reduced, and the construction efficiency is improved. And meanwhile, the overall excavation efficiency can be improved, and the overall construction period is greatly shortened.

Description

Technical Field

[0001] The invention relates to the technical field of dark excavation support structure construction, in particular to a method for constructing an advanced pipe shed suspension structure replacing a dark excavation temporary support. Background Art

[0002] In the existing tunnel excavation construction, in order to avoid earth collapse and deformation of large-span arch frames in the tunnel, it is usually necessary to install grid steel frames inside the excavated tunnel support system and add temporary supports. The temporary supports are composed of horizontally or vertically arranged brackets (steel arch frames or grid steel frames). Although they can play a corresponding supporting role, the connection points between the temporary supports are not firm, which poses a safety hazard. At the same time, the cross-arranged temporary supports also affect the construction of large mechanical equipment, and the overall excavation efficiency is low. The temporary supports need to be dismantled in the later stage, which is not only risky and inefficient, but also wasteful and prolongs the construction period of the overall project. Summary of the invention

[0003] The purpose of the present invention is to provide a construction method for an advanced pipe-roof suspension structure that replaces temporary support for dark excavation. By arranging pre-buried steel wire ropes on steel pipes in the pipe-roof, suspension of the top of the grid steel frame and limited suspension of the arch feet on both sides are realized, thereby replacing traditional temporary support and solving the problems in the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a method for constructing an advanced pipe-roof suspension structure instead of temporary support for dark excavation, comprising the following steps: ① drilling a plurality of pre-buried holes on a tunnel section, wherein the pre-buried holes at the top and both sides are first pre-buried holes, and the pre-buried holes at the remaining positions are second pre-buried holes, and the diameter of the first pre-buried holes is greater than the diameter of the second pre-buried holes; ② after the pre-buried holes in step ① are opened, a first steel pipe is installed in the first pre-buried hole, and a second steel pipe is installed in the second pre-buried hole, the diameter of the first steel pipe is smaller than the diameter of the first pre-buried hole, and a plurality of steel wire ropes are fixedly arranged in the length direction of the first steel pipe, and each steel wire rope is evenly spaced on the first steel pipe, one end of the steel wire rope is opened and connected by a clamp, and the diameter of the second steel pipe The diameter of the first steel pipe and the second steel pipe is smaller than that of the second embedded hole, and grouting holes are provided on the outer circumference of the first steel pipe and the second steel pipe; ③ After the installation of the steel pipe in step ② is completed, cement slurry or cement mortar is injected into the first steel pipe and the second steel pipe respectively through the grouting pipe, and after curing and solidification, the embedded holes are filled to form a pipe shed with a cement-solidified steel pipe structure, wherein the clamps and part of the steel wire ropes on the first steel pipe are located on the outside of the cement slurry layer or cement mortar layer after solidification; ④ After the construction of the pipe shed with a hanging structure in step ③ is completed, the rock or soil of the tunnel range is excavated at the bottom of the pipe shed, and after the excavation reaches the set length, the excavation is stopped, and the steel wire ropes on the first steel pipe at the upper position and the side position are found; ⑤ After the excavation in step ④ is completed, a matching ⑥ After the installation of the first grid steel frame in step ⑤ is completed, continue to excavate the rock or soil within the tunnel range at the bottom of the pipe shed. After the excavation reaches the set length, stop excavating, and find the steel wire ropes on the first steel pipes at the upper and side positions. Install a matching second grid steel frame on the top of the excavated space, adjust the position of the clamp, and allow the side and top steel wire ropes to be sleeved on the end periphery of the second grid steel frame; ⑦ After the installation of the second grid steel frame is completed, tighten the clamp until it contacts the grid steel frame, let the steel wire ropes clamp the grid steel frames on both sides to limit the position, and the top steel wire ropes clamp the grid steel frames to limit the position. The frame forms a suspension and tension in the vertical direction, and the steel wire ropes on both sides form an arch foot limit in the horizontal direction for the grid steel frame; ⑧ After the steel wire ropes in step ⑦ tighten and limit the grid steel frames on both sides, continue to excavate the rock or soil downward in the excavated space. After the excavation reaches the set length, stop excavating, and install a matching third grid steel frame in the newly excavated space. The third grid steel frame is located at the bottom of the first grid steel frame and the second grid steel frame, and is closed into a ring to form a stable support; ⑨ After all the grid steel frames in step ⑧ are installed, continue to excavate inward to the position of the next group of steel wire ropes on the first steel pipe, repeat steps ④-⑧, complete the assembly and connection of each group of grid steel frames in the tunnel, and realize the support construction of the advanced pipe shed suspension structure in the tunnel.In step ③, after the installation of the steel pipe is completed and before grouting, a steel cage is installed inside the first steel pipe. The length direction of the first steel pipe is provided with spaced limit steel sheets, and the steel wire rope is located between the limit steel sheets. The steel wire rope is sleeved with a rubber hose, and the rubber hose is located on the outer periphery of the first steel pipe. The excavation length in steps ④, ⑥, and ⑧ is equal to the spacing between the first grid steel frame, the second grid steel frame, and the third grid steel frame, and each group of assembled grid steel frames is sleeved with a group of steel wire ropes at the top and both sides. The end positions where the first grid steel frame and the second grid steel frame contact are provided with matching plugs and slots, and the steel wire rope is sleeved at the middle position of the plug. In step ⑨, each time the excavation is carried out inward to the position of the next group of steel wire ropes, the assembled grid steel frame is first inspected as a whole to ensure that each connection part is firm and reliable. In step ⑧, after the installation of the third grid steel frame is completed, a waterproof layer needs to be laid at the bottom of the third grid steel frame to prevent groundwater leakage. The clamp is an adjustable clamp that can adjust the tension and position of the wire rope according to actual needs. During the entire construction process, it is also necessary to monitor the air quality, temperature, humidity and other environmental factors in the tunnel in real time to ensure construction safety and quality.

[0005] The positive effect of the present invention is that the advanced pipe-roof suspension structure construction method for replacing temporary support for dark excavation described in the present invention installs a steel pipe with a steel wire rope in the embedded hole, and in the subsequent segmented excavation process, the steel wire rope is fixed on the top and both sides of the first and second grid steel frames, and tightened and limited, and the third grid steel frame is installed by digging downward, so that the three groups of grid steel frames are closed into a ring to achieve relative limitation, which replaces the setting of traditional temporary support and avoids safety hazards. At the same time, it is also convenient for large-scale machinery and equipment to enter the tunnel for operation. There is no need to dismantle the temporary support in the later stage, which not only saves resources and construction costs, reduces risks, reduces unnecessary support construction, and facilitates the organization of mechanized operations, but also improves the overall excavation efficiency and greatly shortens the overall construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is a schematic diagram of the state after the construction step ① in the present invention is completed; Figure 2 This is a schematic diagram of the state after the construction step ② in the present invention is completed; Figure 3 This is a schematic diagram of the state after the construction step ③ in the present invention is completed; Figure 4 This is a schematic diagram of the state after the construction step ④ in the present invention is completed; Figure 5 This is a schematic diagram of the state after the construction step ⑤ of the present invention is completed; Figure 6 This is a schematic diagram of the state after the construction step ⑦ in the present invention is completed; Figure 7 It is a schematic diagram of the state after the construction step ⑧ of the present invention is completed; Figure 8 It is a side view of the state of further digging downwards in the construction step ⑨ of the present invention; Fig. 9 yes Figure 7 A partial enlarged view of middle I; Fig.10 yes Figure 7 A partial enlarged view of middle II; Fig.11 It is a schematic diagram showing the state when the first grid steel frame and the second grid steel frame are spliced ​​together; Fig.12 It is a construction diagram for lifting the steel pipe installation position to the surface; Fig.13 It is a structural diagram of a grid steel frame; Fig.14 It is a structural diagram of an arch frame; Fig.15 It is another suspension diagram of the grid steel frame; Fig.16 It is a schematic diagram of the structure of the grid steel frame suspended by steel wire rope; Fig.17 is a schematic diagram of the structure of the second steel pipe; Fig.18 It is a force diagram of the present invention during the construction process. DETAILED DESCRIPTION

[0007] The invention discloses a method for constructing an advanced pipe-roof suspension structure replacing temporary support for underground excavation, such as Figure 1-8 As shown, the following steps are included: ① Drill several embedded holes on the tunnel section, among which the embedded holes at the top and both sides are first embedded holes 1, and the embedded holes at other positions are second embedded holes 2. The diameter of the first embedded hole 1 is larger than the diameter of the second embedded hole 2; ② After the embedded holes in step ① are opened, a first steel pipe 3 is installed in the first embedded hole 1, and a second steel pipe 4 is installed in the second embedded hole 2. The diameter of the first steel pipe 3 is smaller than the diameter of the first embedded hole 1. A plurality of steel wire ropes 5 are fixedly arranged in the length direction of the first steel pipe 3. The steel wire ropes 5 are evenly spaced on the first steel pipe 3, and the spacing is equal to the spacing of the dark excavated grid steel frame. One end of the steel wire rope 5 is opened and connected by a clamp 6. The diameter of the second steel pipe 4 is smaller than the diameter of the second embedded hole 2. Grouting holes 15 are opened on the outer periphery of the first steel pipe 3 and the second steel pipe 4; ③ After the installation of the steel pipe in step ② is completed, cement slurry or cement mortar is injected into the first steel pipe 3 and the second steel pipe 4 through the grouting pipe, and after curing and solidification, the embedded hole is filled to form a pipe shed of cement solidified steel pipe structure, wherein the clamp 6 and part of the steel wire rope 5 on the first steel pipe 3 are located outside the cement slurry layer or cement mortar layer after solidification; ④ After the construction of the pipe shed with the hanging structure in step ③ is completed, the rock or soil of the tunnel range is excavated at the bottom of the pipe shed. After the excavation reaches the set length, the excavation is stopped, and the steel wire rope 5 on the first steel pipe 3 at the upper position and the side position is found; ⑤ After the excavation in step ④ is completed, a matching first grid steel frame 7 is installed on the top of the excavated space, and the position of the clamp 6 is adjusted so that the side wire rope 5 and the top wire rope 5 are both sleeved on the outer periphery of the end of the first grid steel frame 7; ⑥ After the installation of the first grid steel frame 7 in step ⑤ is completed, continue to excavate the rock or soil within the tunnel range at the bottom of the pipe shed. After the excavation reaches the set length, stop excavating, and find the steel wire rope 5 on the first steel pipe 3 at the upper position and the side position, and install the matching second grid steel frame 8 on the top of the excavated space, and adjust the position of the clamp 6 so that the side wire rope 5 and the top wire rope 5 are both sleeved on the outer periphery of the end of the second grid steel frame 8; ⑦ After the second grid steel frame 8 is installed, tighten the clamp 6 until it contacts the grid steel frame, and let the steel wire rope 5 clamp the grid steel frames on both sides to limit the position. The steel wire rope 5 on the top forms a vertical suspension tension for the grid steel frame, and the steel wire ropes 5 on both sides form an arch foot limit for the grid steel frame in the horizontal direction; ⑧ After the steel wire rope 5 in step ⑦ has tightened the grid steel frames on both sides to limit their positions, continue to dig the rock or soil downward in the excavated space. After the excavation reaches the set length, stop the excavation and install a matching third grid steel frame 9 in the newly excavated space. The third grid steel frame 9 is located at the bottom of the first grid steel frame 7 and the second grid steel frame 8, and is closed into a ring to form a stable support; ⑨ After all grid steel frames in step ⑧ are installed, continue to dig inward to the position of the next group of steel wire ropes 5 on the first steel pipe 3, repeat steps ④-⑧, complete the assembly and connection of each group of grid steel frames in the tunnel, and realize the support construction of the advanced pipe shed suspension structure in the tunnel.

[0008] The spacing between the steel wire ropes 5 on the first steel pipe 3 is equal to the longitudinal spacing of the dark excavation steel arch frame or the grid steel frame.

[0009] The production of the pipe shed, on the one hand, realizes grouting to reinforce the soil above the tunnel, forming a scaffolding to prevent tunnel collapse. On the other hand, the setting of steel pipes allows the entire tunnel boring machine to install the grid steel frame, with the soil support in the front and the closed steel frame support in the rear to form a stable simply supported beam structure. The installed steel wire ropes ensure the safety of the tunnel structure by hanging the grid steel frame, which is used to replace the horizontal and vertical supports set up inside the tunnel in traditional construction operations.

[0010] The above-mentioned first embedded hole 1 and the second embedded hole 2 can be arranged in a semicircle to adapt to the arched shape of the top of the tunnel to be excavated later and provide necessary support for the top of the tunnel. The first embedded hole 1 at the top and both sides has a larger diameter to increase the supporting strength of the internal steel pipe after concrete pouring.

[0011] The first embedded hole 1 is provided with a first steel pipe 3, and steel wire ropes 5 are evenly spaced in the length direction of the first steel pipe 3. The steel wire ropes 5 are provided with position-adjustable clamps 6, and the diameter of the ring formed at the bottom of the steel wire rope 5 is adjusted by the clamps 6 to adapt to grid steel frames of different thicknesses. The position of each steel wire rope 5 corresponds to the grid steel frame at the bottom. In the later excavation process, the pre-embedded steel wire ropes 5 can be found, and the position of the clamps 6 can be adjusted to set the steel wire ropes 5 on the periphery of the grid steel frame, which plays the role of top suspension and arch foot limit on both sides of the grid steel frame.

[0012] The diameter of the steel pipe is smaller than the diameter of the embedded hole, in order to facilitate the installation of the steel pipe in the embedded hole. The steel wire rope 5 with the clamp 6 is located between the steel pipe and the embedded hole wall. The outer periphery of the steel pipe is provided with a grouting hole 15. After the cement slurry or cement mortar is injected, a cement solidification layer can be formed between the steel pipe and the embedded hole, so that the steel pipe forms a cement solidified steel pipe structure in the embedded hole, further improving the overall strength of the tunnel top pipe shed. The clamp 6 and part of the steel wire rope 5 are located outside the cement solidification layer, so that the steel wire rope 5 with the clamp 6 can be found in the subsequent excavation process, and the diameter of the ring is adjusted to fit the outer periphery of the grid steel frame to achieve the corresponding support limit. The embedded holes inside and outside the first steel pipe 3 and the second steel pipe 4 can be filled with cement mortar or fine stone concrete to improve the strength of the overall structure. The steel wire rope 5 can also be replaced with an existing steel strand. The clamp 6 allows the steel wire rope 5 to be tightened and firmly and fixedly fitted on the grid steel frame to form a limit.

[0013] The overall excavation process adopts a step-by-step push-through repetitive operation. After the steel pipe with the steel wire rope 5 is pre-buried, the construction at each section includes three relatively independent excavation and steel frame support operations, that is, the space of one-quarter of the circumference can be excavated first, and then the corresponding first grid steel frame 7 is installed. After that, the space of one-quarter of the circumference on the other side is excavated, and then the corresponding second grid steel frame 8 is installed. The position of the clamp 6 is adjusted to tighten the steel wire rope 5 mounted on the grid steel frame to limit the position, and finally excavate downward and install the corresponding third grid steel frame 9, so that the third grid steel frame 9 and the first grid steel frame 7 and the second grid steel frame 8 are closed into a ring to form a stable support between each other.

[0014] During the above-mentioned excavation operation step by step, a set length will be excavated inward each time. During the excavation process, the rear end of the steel pipe will be supported by the un-excavated rock layer, and the front end of the steel pipe will be supported by the closed ring grid steel frame, which is equivalent to forming a simple bracket support for the steel pipe. The suspended position is only the set length space to be excavated each time. Therefore, during the overall construction process, a more stable support can be formed for the pipe shed made of steel pipes. During each excavation process, only a small section of the grid steel frame installation will exert a downward force on the embedded steel pipe, which will not cause deformation of the steel pipe and other adverse conditions. The overall construction is carried out efficiently and safely through the step-by-step installation method of excavation, installation of grid steel frame, and connection and fixation.

[0015] Furthermore, in order to enhance the strength of the first steel pipe 3 and ensure the stable suspension of the grid steel frame and the stable limit of the arch feet on both sides, after the steel pipe is installed in step ③ and before grouting, a steel cage 10 is installed inside the first steel pipe 3, so that a reinforced concrete structure will be formed inside the first steel pipe 3 after grouting, thereby improving the strength of the first steel pipe 3 in the embedded hole and increasing the strength and rigidity of the steel pipe simply supported beam. The steel cage 10 can be selected to be installed according to the stress condition of the steel pipe.

[0016] The steel wire rope 5 can be welded and fixed on the first steel pipe 3. In order to facilitate the installation of the steel wire rope 5 on the first steel pipe 3 at a set length distance, spaced limit steel sheets 11 can also be set in the length direction of the first steel pipe 3. The steel wire rope 5 is located between the limit steel sheets 11. When the first steel pipe 3 is installed in the embedded hole, the steel wire rope 5 will bend in the opposite direction of the steel pipe feeding direction under the action of friction. Due to the setting of the limit steel sheets 11, even if the steel wire rope 5 is bent, it will not separate from the two limit steel sheets 11 on the first steel pipe 3, thereby ensuring that each first steel pipe 3 on each group of grid steel frames will retain at least one group of steel wire ropes 5 to complete the subsequent suspension and arch foot limiting.

[0017] After the cement slurry or cement mortar is injected, the steel wire rope 5 may move in a circular motion relative to the steel pipe under the impact of the cement slurry or cement mortar, causing the clamp 6 to leave the initial position, thereby causing the cement slurry or cement mortar to wrap and solidify, and it is impossible to adaptively adjust the ring diameter of the steel wire rope 5 in the subsequent construction. In order to solve the above problem, the steel wire rope 5 is sheathed with a rubber hose 12, and the rubber hose 12 is located on the outer periphery of the first steel pipe 3. After the cement slurry or cement mortar is injected, most of it will be filled between the rubber hose 12 and solidify, and a small part of the slurry will not affect the steel wire rope 5 with the clamp 6. After the subsequent solidification is completed, the clamp 6 and part of the steel wire rope 5 will still remain outside the solidified concrete. When adjusting the clamp 6, the steel wire rope 5 can be moved and adjusted relative to the rubber hose 12, so as to facilitate the adjustment of the diameter of the steel wire rope 5 sheathed on the outer periphery of the grid steel frame, and realize the suspension of grid steel frames of different thickness types and the limitation of the arch feet on both sides. The provision of the rubber hose 12 can also prevent the strength reduction caused by rusting of the steel wire rope 5 .

[0018] Furthermore, the excavation length in steps ④, ⑥, and ⑧ is equal to the spacing between the first grid steel frame 7, the second grid steel frame 8, and the third grid steel frame 9. A group of steel wire ropes 5 are mounted on the top and both sides of each assembled grid steel frame. The above excavation length is adapted to the spacing between adjacent steel wire ropes 5 and the thickness of the grid steel frame, thereby realizing a step-by-step repeated operation during the excavation process.

[0019] Furthermore, in order to enable a group of steel wire ropes 5 at the top to achieve corresponding suspension of the top positions of the first grid steel frame 7 and the second grid steel frame 8 on both sides, as shown in FIG. Fig.11 As shown, the contact end positions of the first grid steel frame 7 and the second grid steel frame 8 are provided with matching plug blocks 13 and slots 14, and the steel wire rope 5 is sleeved in the middle position of the plug block 13. The first grid steel frames 7 and the second grid steel frames 8 on both sides can be plugged in and fixed, and one steel wire rope 5 can also realize the suspension support of the grid steel frames on both sides at the same time.

[0020] The width of the grid steel frame is generally about 20cm, the thickness of the sprayed concrete is 30cm, the spacing of the grid steel frame is 50cm, and the pre-buried steel wire rope is located on one side of the grid steel frame. When the tunnel is excavated and before the arch frame is installed, find the pre-buried steel wire rope, hang it on the grid steel frame and fix it firmly.

[0021] During the installation of the grid steel frame, different numbers of assembly types can be selected according to the size of the tunnel section. For example, a smaller tunnel section can use three grid steel frames to form a closed body, while a larger tunnel section can use six, eight, or nine unit grid steel frames to form a closed body. The grid steel frame's material feeding can be reasonably set according to the size of the tunnel section, which can not only ensure the support stability during the operation, but also simplify the installation process to a certain extent and improve the operation efficiency.

[0022] The overall shape of the steel pipe can be a round pipe or a square pipe, as long as it can support and suspend the steel wire rope 5 and reach a certain strength. The grid steel frame installed after the tunnel excavation is completed can also be replaced by an existing arch frame, wherein the structure of the grid steel frame can be as follows: Fig.13 or Fig.14 As shown, it can be composed of four curved steel bars and peripheral stirrups, and the arch frame can be an H-shaped steel with a bend to achieve its own stable supporting performance.

[0023] Furthermore, in order to allow the steel pipes that support the suspension to be recycled, such as Fig.12 As shown, the steel pipe can be pre-buried below the ground surface. The operation required is to dig a shallow groove for placing the steel pipe along the length direction above the ground surface at the tunnel excavation location, and drill a number of holes downward in the length direction of the shallow groove. The bottom of the hole needs to be connected to the tunnel section to be excavated subsequently. The spacing between adjacent holes is the installation spacing of the grid steel frame. Then, a steel wire rope 5 is loaded into each hole, and the steel wire rope 5 with a clamp 6 is located at the bottom of the hole. The upper end of the steel wire rope 5 is located in the shallow groove. Subsequently, a steel pipe is loaded into the shallow groove, and the steel wire rope 5 is fixed to the connected steel pipe to play a corresponding hanging support. The construction operation in the subsequent tunnel excavation process is similar. The steel wire rope 5 with the clamp 6 is found, and after the grid steel frame is installed, the steel wire rope 5 is fixedly installed to the top and the support foot position of the grid steel frame to form a stable grid steel frame structure. After the overall tunnel construction is completed, the grid steel frame in the tunnel section forms a stable support, and there is no need for the hanging support of the wire rope 5. The wire rope 5 on the steel pipe located on the surface can be removed and the steel pipe can be recycled, and finally the shallow trench can be backfilled.

[0024] During the construction process, the distance between the borehole and the excavation surface is reasonably determined according to the hydrogeological conditions and the construction accuracy of the drilling machine, that is, the distance between the borehole and the arch frame is reasonably determined to prevent the erected pipe shed or the excavated hole from invading the excavation range. The size of the borehole is selected according to the actual situation, and the choice of wire rope is selected according to the force of the grid steel frame. Fig.15 Shown is another schematic diagram of the suspension of the grid steel frame, wherein adjacent grid steel frames can be connected by bolts, and the connection position is located on one side of the steel wire rope 5, which will not interfere with the normal suspension of the steel wire rope 5.

[0025] Furthermore, in step ⑨, each time the excavation is carried out to the position of the next set of steel wire ropes 5, the assembled grid steel frame is first inspected as a whole to ensure that each connection part is firm and reliable. In step ⑧, after the third grid steel frame 9 is installed, a waterproof layer needs to be laid at the bottom of the third grid steel frame 9 to prevent groundwater leakage. The clamp 6 is an adjustable clamp that can adjust the tension and position of the steel wire rope 5 according to actual needs. During the entire construction process, it is also necessary to monitor the air quality, temperature, humidity and other environmental factors in the tunnel in real time to ensure construction safety and quality.

[0026] The technical solution of the present invention is not limited to the scope of the embodiments described in the present invention. The technical contents not described in detail in the present invention are all well-known technologies.

Claims

1. A construction method for an advanced pipe-roof suspension structure replacing temporary support for dark excavation, characterized in that: The method comprises the following steps: ① drilling a plurality of pre-buried holes on a tunnel section, wherein the pre-buried holes at the top and both sides are first pre-buried holes (1), and the pre-buried holes at other positions are second pre-buried holes (2), and the diameter of the first pre-buried hole (1) is greater than the diameter of the second pre-buried hole (2); ② After the pre-buried holes in step ① are opened, a first steel pipe (3) is installed in the first pre-buried hole (1), and a second steel pipe (4) is installed in the second pre-buried hole (2), the diameter of the first steel pipe (3) is smaller than the diameter of the first pre-buried hole (1), a plurality of steel wire ropes (5) are fixedly arranged in the length direction of the first steel pipe (3), each steel wire rope (5) is evenly spaced on the first steel pipe (3), one end of the steel wire rope (5) is open and connected by a clamp (6), the diameter of the second steel pipe (4) is smaller than the diameter of the second pre-buried hole (2), and grouting holes (15) are opened on the outer circumference of the first steel pipe (3) and the second steel pipe (4); ③ After the installation of the steel pipes in step ② is completed, cement slurry or cement mortar is injected into the first steel pipe (3) and the second steel pipe (4) through the grouting pipe, and after curing and solidification, the embedded holes are filled to form a pipe shed of a cement-solidified steel pipe structure, wherein the clamp (6) and part of the steel wire rope (5) on the first steel pipe (3) are located outside the cement slurry layer or cement mortar layer after solidification; ④ After the construction of the pipe shed with the hanging structure in step ③ is completed, rock or soil excavation of the tunnel range is carried out at the bottom of the pipe shed. After the excavation reaches the set length, the excavation is stopped, and the steel wire rope (5) on the first steel pipe (3) at the upper position and the side position is found; ⑤ After the excavation in step ④ is completed, a matching first grid steel frame (7) is installed on the top of the excavated space, and the position of the clamp (6) is adjusted so that the side wire rope (5) and the top wire rope (5) are both sleeved on the outer periphery of the end of the first grid steel frame (7); ⑥ After the installation of the first grid steel frame (7) in step ⑤ is completed, continue to excavate the rock or soil within the tunnel range at the bottom of the pipe shed. After the excavation reaches the set length, stop excavating, find the steel wire rope (5) on the first steel pipe (3) at the upper position and the side position, install a matching second grid steel frame (8) at the top of the excavated space, adjust the position of the clamp (6), and allow the side steel wire rope (5) and the top steel wire rope (5) to be sleeved on the outer periphery of the end of the second grid steel frame (8); ⑦ After the second grid steel frame (8) is installed, tighten the clamp (6) until it contacts the grid steel frame, and allow the steel wire ropes (5) to clamp the grid steel frames on both sides to limit the grid steel frames, so that the steel wire ropes (5) at the top form a vertical suspension tension for the grid steel frame, and the steel wire ropes (5) on both sides form an arch foot limit for the grid steel frame in the horizontal direction; ⑧ After the steel wire rope (5) in step ⑦ has tightened the grid steel frames on both sides to limit their positions, the rock or soil is continued to be excavated downward in the excavated space. After the excavation reaches a set length, the excavation is stopped, and a matching third grid steel frame (9) is installed in the newly excavated space. The third grid steel frame (9) is located at the bottom of the first grid steel frame (7) and the second grid steel frame (8), and is closed into a ring to form a stable support; ⑨ After all grid steel frames in step ⑧ are installed, continue to dig inward to the position of the next set of steel wire ropes (5) on the first steel pipe (3), repeat steps ④-⑧, complete the assembly and connection of each set of grid steel frames in the tunnel, and realize the support construction of the advanced pipe shed suspension structure in the tunnel.

2. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: In step ③, after the steel pipe is installed and before grouting, a steel cage (10) is placed inside the first steel pipe (3).

3. The construction method of an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: The first steel tube (3) is provided with spaced-apart limiting steel sheets (11) in the length direction, and the steel wire rope (5) is located between the limiting steel sheets (11).

4. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: A rubber hose (12) is sleeved on the steel wire rope (5), and the rubber hose (12) is located on the outer periphery of the first steel pipe (3).

5. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: The excavation length in steps ④, ⑥ and ⑧ is equal to the spacing between the first grid steel frame (7), the second grid steel frame (8) and the third grid steel frame (9), and a set of steel wire ropes (5) are mounted on the top and both sides of each set of assembled grid steel frames.

6. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: Matching plug blocks (13) and slots (14) are provided at the contacting end positions of the first grid steel frame (7) and the second grid steel frame (8), and the steel wire rope (5) is sleeved at the middle position of the plug block (13).

7. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: In step ⑨, each time the excavation is carried out inwards to the position of the next set of steel wire ropes (5), the assembled grid steel frame is first inspected as a whole to ensure that each connection part is firm and reliable.

8. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: In step ⑧, after the third grid steel frame (9) is installed, a waterproof layer needs to be laid at the bottom of the third grid steel frame (9) to prevent groundwater leakage.

9. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: The clamp (6) is an adjustable clamp, and can adjust the tension and position of the steel wire rope (5) according to actual needs.

10. The method for constructing an advanced pipe-roof suspension structure replacing temporary support for dark excavation according to claim 1 is characterized in that: During the entire construction process, it is also necessary to monitor environmental factors such as air quality, temperature, and humidity in the tunnel in real time to ensure construction safety and quality.

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