Tunnel entrance reinforcement structure

Abstract

The present invention relates to the technical field of tunnel support, and discloses a tunnel entrance section reinforcement structure, including several groups of support units and protection units tightly assembled in the tunnel, the support unit including a top plate and two side plates, the top plate is attached to the top of the tunnel inner wall, the two side plates are respectively attached to the two sides of the tunnel inner wall, and the two side plates are detachably connected to the top plate, and several through holes are provided in the side plates along the height direction; the protection unit includes several external conduits, and the several external conduits respectively penetrate through the through holes at the same height on the side plates, and one end of the external conduit is located outside the tunnel entrance, and the other end of the external conduit is located in the tunnel and is covered with an expandable and contractible air bag. The present invention can effectively improve the construction efficiency of the reinforcement structure by providing a support unit that is convenient for disassembly and assembly, and at the same time, the protection unit is provided to play a protective role when the tunnel entrance collapses.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel support, and in particular to a tunnel entrance section reinforcement structure. Background Art

[0002] Tunnel excavation destroys the initial stress balance of the stratum, which is prone to surrounding rock stress release and cavern deformation, which seriously affects the safety of the tunnel structure and the construction efficiency. In order to strictly control the release rate of surrounding rock stress and the deformation of the cavern, it is necessary to add initial support structures during tunnel excavation to support and protect the tunnel in the early stage of construction. The support at the tunnel entrance is particularly important. The existing entrance support structures are mostly shotcrete or I-beams. Although they can play a certain supporting role, they do not have an emergency protection function when a collapse occurs at the tunnel entrance. Once a collapse occurs, it is easy to completely isolate the tunnel from the outside world, causing hypoxia and water shortage in the tunnel, threatening the lives of construction workers and bringing inconvenience to rescue. Summary of the invention

[0003] In order to solve the technical problems raised in the background technology, the present invention provides a tunnel entrance section reinforcement structure.

[0004] The present invention is implemented by the following technical scheme: the tunnel entrance section reinforcement structure includes a plurality of groups of support units and protection units tightly assembled in the tunnel, the support unit includes a top plate and two side plates, the top plate is attached to the top of the tunnel inner wall, the two side plates are attached to the two sides of the tunnel inner wall respectively, and the two side plates are detachably connected to the top plate, and a plurality of through holes are opened in the side plates along the height direction;

[0005] The protection unit comprises a plurality of outer conduits, which respectively penetrate through holes at the same height on the side plates, one end of the outer conduit is located outside the tunnel opening, and the other end of the outer conduit is located in the tunnel and is covered with an expandable and contractible air bag.

[0006] This scheme can effectively improve the construction efficiency of the reinforced structure by providing support units that are easy to disassemble and assemble. At the same time, a protection unit is provided to play a protective role when the tunnel entrance collapses. Specifically, the tunnel and the external space are connected through an external duct to avoid the phenomenon of hypoxia in the tunnel due to blockage of the entrance, which can effectively improve the safety of construction and the survival rate of personnel after an accident.

[0007] As a further improvement of the above scheme, the top surface of the side plate is provided with a plurality of rotation grooves, a bottom column is rotatably installed at each rotation groove, a threaded groove is opened on the top surface of each bottom column, and a threaded rod is spirally installed at the threaded groove, a top column is fixed at the top end of the threaded rod, a connecting head is fixed at the top end of the top column, and a connecting seat that cooperates with the connecting head is connected to the bottom surface of the top plate, and the connecting seat and the connecting head are relatively fixed in the radial direction of the threaded rod.

[0008] As a further improvement of the above solution, a fixing sleeve is sleeved on the outer side of the bottom column, and the top plate and the connecting seat are connected in vertical rotation via a hinge.

[0009] Through the above scheme, when the side panels are installed on one side of the tunnel side wall, the top panel is lifted to a certain height using construction equipment, so that the connecting seat below the top panel and the connecting head above the side panel are engaged, and then the top panel can be lifted upward by rotating the fixing sleeve, and finally the top panel and the top of the inner wall of the tunnel are in contact, thereby playing a supporting and protective role.

[0010] As a further improvement of the above scheme, a protective plate is fixed to the outer side of the side plate in the supporting unit near the tunnel entrance, and a guide hole 1 is opened on the protective plate. A drill hole 1 is opened in the rock mass next to the tunnel entrance along the guide hole 1. A number of guide holes 2 are also opened on the side plate, and a number of drill holes 2 are opened in the inner wall of the tunnel along the guide hole 2. The drill holes 2 are connected to the drill hole 1, an inner guide tube is inserted in the drill hole 1, and a connecting pipe is inserted in the drill hole 2. The end of the connecting pipe is connected to the inner guide tube.

[0011] Through the above scheme, a connected borehole 1 and borehole 2 can be formed in the rock mass on one side of the tunnel, thereby forming a passage that can connect to the interior of the tunnel, and connecting pipes and inner conduits are installed in each passage, so that when the tunnel entrance collapses, water or oxygen can be transported into the tunnel through the passage formed by the connecting pipes and the inner conduits. At the same time, since the connecting pipes are connected to the side plates, the support can be further strengthened.

[0012] As a further improvement of the above scheme, several docking holes are provided on the inner conduit, and the ends of the connecting pipes are inserted into the inner conduit through the docking holes. The outer wall of the outer end of the inner conduit is axially provided with positioning ridges, and the inner wall of the guide hole is provided with guide grooves that cooperate with the positioning ridges. The outer wall of the inner conduit is provided with several elastic expansion rings to make the connection between the inner conduit and the drill hole more tightly.

[0013] Through the above scheme, the inner conduit can be accurately installed, which facilitates the subsequent connection pipe to be accurately plugged in and connected with the inner conduit, thereby improving construction efficiency.

[0014] As a further improvement of the above scheme, it also includes two support seats symmetrically laid on the tunnel floor, the bottom surfaces of the two side panels are slidably connected to the two support seats respectively, and rolling boxes are rotatably installed on the adjacent sides of the two side panels, the bottom end height of the rolling box is higher than the bottom surface of the support seat, and a height adjustment mechanism is also arranged on the outer side of the rolling box, and the height adjustment mechanism can change the bottom surface height of the side panel;

[0015] A center hole is opened at the center of the rolling box, a center tube is movably passed through the center hole, one end of the center tube is fixed to the side plate, and a limiting sleeve is installed at the other end of the center tube.

[0016] Through the above scheme, the support seat is first fixed at the designated position on the tunnel ground, which is conducive to the subsequent movement and installation of the side panels, improves the construction efficiency, and saves time and labor during construction.

[0017] As a further improvement of the above scheme, the height adjustment mechanism includes a plurality of fan-shaped plates distributed on the outside of the rolling box, an arc plate is installed at the end of each fan-shaped plate, the arc plate is arranged on the annular outer peripheral side of the rolling box, and each fan-shaped plate is slidably connected to one side end face of the rolling box, and the fan-shaped plate slides circumferentially along the central axis of the rolling box. When each fan-shaped plate slides to be evenly distributed on the outside of the rolling box, the outer side of the arc plate can contact the tunnel ground to lift the side plate.

[0018] Through the above scheme, when the side panel is moved, the arc plate in the height adjustment mechanism can be moved to the outside of the rolling box to be evenly distributed. At this time, the side panel is slightly lifted up to reduce the friction between the bottom of the side panel and the support seat. In this way, the rolling effect of the rolling box can be utilized when moving the side panel, making the construction more labor-saving and convenient.

[0019] As a further improvement of the above scheme, a slider is installed on the inner side of the fan-shaped plate, and an annular groove coaxially arranged therewith is opened on the outer surface of the rolling box. The slider is slidably connected to the annular groove. A driving motor is also fixed on the fan-shaped plate. The output shaft of the driving motor movably passes through the fan-shaped plate and is connected to a driving gear. An annular gear plate coaxial with the fan-shaped plate is connected to the outer side of the rolling box, and the annular gear plate and the driving gear are meshed.

[0020] As a further improvement of the above scheme, a convex plate is fixed on the outside of the rolling box, a through hole is opened on the convex plate, a fastening bolt spirally connected to the side plate is installed at the through hole, a groove is provided on one side of the adjacent side plate of the rolling box, a number of docking tubes are distributed in the groove, when the rolling box and the side plate are fixed, the end of the docking tube can dock with the outer port of the connecting tube on the side plate.

[0021] When the side plate is moved to a suitable position, the height adjustment mechanism is reset, so that the bottom of the side plate is stably contacted with the support seat again, and then the rolling box and the side plate are fixed by fastening bolts passing through the convex plate.

[0022] As a further improvement of the above scheme, it also includes two protection boxes respectively arranged on both sides of the hole, the outer ends of the outer conduits all pass through the protection boxes, and a number of sockets are opened on the top plate, and hollow reinforcing rods are connected to the outer ends of some of the sockets, and the other end of the reinforcing rods is connected to the outer end of the outer conduit, and the outer conduit, the protection box, the reinforcing rod and the sockets are interconnected.

[0023] Through the above scheme, when the tunnel entrance collapses, water is injected into the protection box. At this time, since the external conduit, the protection box, the reinforcing rod and the socket are connected, water can be transported into the tunnel, thereby rescuing the construction workers trapped in the tunnel.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The tunnel entrance section reinforcement structure proposed by the present invention includes several groups of support units and protection units tightly assembled in the tunnel, the support unit includes a top plate and two side plates, the top plate is attached to the top of the inner wall of the tunnel, the two side plates are respectively attached to the two sides of the inner wall of the tunnel, and the two side plates are detachably connected to the top plate, and several through holes are opened in the side plates along the height direction; the protection unit includes several external guide tubes, the several external guide tubes respectively penetrate the through holes at the same height on the side plates, and one end of the external guide tube is located outside the tunnel entrance, and the other end of the external guide tube is located in the tunnel and is covered with an expandable and contractible air bag.

[0026] The present invention can effectively improve the construction efficiency of the reinforced structure by providing a support unit that is easy to disassemble and assemble. At the same time, a protection unit is provided to play a protective role when the tunnel entrance collapses. Specifically, the tunnel and the external space are connected through an external conduit to avoid the phenomenon of hypoxia in the tunnel due to blockage of the entrance, which can effectively improve the safety of construction and the survival rate of personnel after an accident. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a three-dimensional diagram of the overall structure of the reinforcement structure proposed by the present invention;

[0028] Figure 2 A schematic diagram of the three-dimensional structure of the reinforcement structure proposed by the present invention from another perspective;

[0029] Figure 3 It is a schematic diagram of the three-dimensional structure of the side plate and the rolling box in the reinforcement structure proposed by the present invention;

[0030] Figure 4 The present invention proposes Figure 3 Schematic diagram of the three-dimensional structure from another perspective of the middle structure;

[0031] Figure 5 A schematic diagram of the three-dimensional structure of the rolling box and the height adjustment mechanism proposed by the present invention;

[0032] Figure 6 For the present invention Figure 5 A three-dimensional diagram of the structure from another perspective;

[0033] Figure 7 This is a schematic cross-sectional structure diagram of the rolling box proposed by the present invention.

[0034] Description of main symbols:

[0035] In the figure: 1, top plate; 101, jack; 2, connecting seat; 3, side plate; 4, outer conduit; 401, connecting hole; 5, inner conduit; 6, connecting pipe; 7, supporting seat; 8, protective plate; 9, protective box; 10, pressure plate; 11, reinforcing rod; 12, height adjustment mechanism; 13, connector; 14, top column; 15, threaded rod; 16, bottom column; 17, fixing sleeve; 18, fan-shaped plate; 19, driving motor; 20, annular gear plate; 21, rolling box; 22, annular groove; 23, arc plate; 24, groove; 25, center tube; 26, convex plate; 27, butt tube; 28, driving gear; 29, limit sleeve. DETAILED DESCRIPTION

[0036] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0037] Example 1: Reference Figure 1-Figure 7 The tunnel entrance section reinforcement structure proposed in this scheme includes several groups of support units and protection units tightly assembled in the tunnel. The support unit includes a top plate 1 and two side plates 3. The side plates 3 can be made of H-shaped steel as the skeleton, and are made of steel plates after welding steel pipes on the outside of the H-shaped steel. The top plate 1 is attached to the top of the inner wall of the tunnel, and the two side plates 3 are respectively attached to the two sides of the inner wall of the tunnel, and the two side plates 3 are detachably connected to the top plate 1, and a plurality of through holes are opened in the side plates 3 along the height direction.

[0038] The protection unit includes a plurality of outer conduits 4, which respectively penetrate through holes at the same height on the side plate 3, and one end of the outer conduit 4 is located outside the tunnel opening, and the other end of the outer conduit 4 is located in the tunnel and is covered with an expandable and contractible airbag (not shown). Under normal circumstances, the interior of the outer conduit 4 is connected to the airbag. When the tunnel opening collapses, the airbag can be cut open, so that the external gas can be introduced into the tunnel using the outer conduit 4.

[0039] The present invention can effectively improve the construction efficiency of the reinforced structure by providing a support unit that is easy to disassemble and assemble. At the same time, a protection unit is provided to play a protective role when the tunnel entrance collapses. Specifically, the tunnel and the external space are connected through the external conduit 4 to avoid the phenomenon of hypoxia in the tunnel due to blockage of the entrance, which can effectively improve the safety of construction and the survival rate of personnel after an accident.

[0040] Reference Figure 1-Figure 3As an optional embodiment of the present invention, the top surface of the side panel 3 is provided with a plurality of rotation grooves, and a bottom column 16 is rotatably installed at each rotation groove. A threaded groove is opened on the top surface of each bottom column 16, and a threaded rod 15 is spirally installed at the threaded groove. A top column 14 is fixed to the top of the threaded rod 15, and a connecting head 13 is fixed to the top of the top column 14. The bottom surface of the top plate 1 is connected to a connecting seat 2 that cooperates with the connecting head 13, and the connecting seat 2 and the connecting head 13 are relatively fixed in the radial direction of the threaded rod 15.

[0041] A fixing sleeve 17 is sleeved on the outer side of the bottom column 16, and the top plate 1 and the connecting seat 2 are connected in vertical rotation by a hinge. The outer surface of the fixing sleeve 17 is set in the shape of a hexagonal nut for easy twisting.

[0042] According to the present invention, after the side panel 3 is installed on one side of the tunnel side wall, the top panel 1 is lifted to a certain height by means of construction equipment, so that the connecting seat 2 below the top panel 1 and the connecting head 13 above the side panel are engaged, and then the top panel 1 can be lifted upward by rotating the fixing sleeve 17, so that the top panel 1 is finally in contact with the top of the inner wall of the tunnel, thereby playing a supporting and protective role.

[0043] It should be noted that a protective plate 8 is fixed to the outer side of the side plate 3 in the support unit near the tunnel entrance, and a guide hole 1 (not marked) is opened on the protective plate 8, and a drill hole 1 (not marked) is opened in the rock mass next to the tunnel entrance along the guide hole 1. A number of guide holes 2 (not marked) are also opened on the side plate 3, and a number of drill holes 2 (not marked) are opened on the inner wall of the tunnel along the guide hole 2. The drill holes 2 are connected to the drill hole 1, an inner guide tube 5 is inserted in the drill hole 1, and a connecting pipe 6 is inserted in the drill hole 2. The end of the connecting pipe 6 is connected to the inner guide tube 5 and connected.

[0044] Through the above scheme, the present invention can form a connected borehole 1 and a connected borehole 2 in the rock mass on one side of the tunnel, thereby forming a passage that can connect to the inside of the tunnel, and install a connecting pipe 6 and an inner conduit 5 in each passage, so that when the tunnel entrance collapses, water or oxygen can be transported into the tunnel through the passage formed by the connecting pipe 6 and the inner conduit 5. At the same time, since the connecting pipe 6 is connected to the side plate 3, the support can be further strengthened.

[0045] Reference Figure 4 A plurality of docking holes are provided on the inner conduit 5, and the ends of the connecting tubes 6 are inserted into the inner conduit 5 through the docking holes. The outer wall of the outer end of the inner conduit 5 is provided with positioning ridges along the axial direction, and the inner wall of the guide hole is provided with guide grooves that cooperate with the positioning ridges. The outer wall of the inner conduit 5 is provided with a plurality of elastic expansion rings to make the connection between the inner conduit 5 and the drill hole 1 tighter.

[0046] The present invention can accurately install the inner conduit 5 through the guide groove and the positioning convex ridge, so as to facilitate the subsequent accurate insertion and connection of the connecting pipe 6 with the inner conduit 5, thereby improving the construction efficiency.

[0047] The reinforcement structure proposed in the present invention also includes two support seats 7 symmetrically laid on the tunnel floor. The bottom surfaces of the two side panels 3 are respectively slidably connected to the two support seats 7. The adjacent sides of the two side panels 3 are rotatably installed with rolling boxes 21. The bottom end height of the rolling box 21 is higher than the bottom surface of the support seat 7, and a height adjustment mechanism 12 is also provided on the outer side of the rolling box 21. The height of the bottom surface of the side panel 3 can be changed.

[0048] In this solution, a center hole is opened at the center of the rolling box 21, and a center tube 25 is movably inserted into the center hole. One end of the center tube 25 is fixed to the side plate 3, and a limiting sleeve 29 is installed at the other end of the center tube 25. A spiral connection can be adopted between the limiting sleeve 29 and the center tube 25 so that the limiting sleeve 29 can be pressed against the outer surface of the rolling box 21.

[0049] During the specific work, the support seat 7 is first fixed at a designated position on the tunnel ground, which is conducive to the subsequent moving and installing of the side plate 3, improves the efficiency of the construction, and saves time and labor during the construction.

[0050] Reference Figure 5 and Figure 6 The height adjustment mechanism 12 proposed by the present invention includes a plurality of fan-shaped plates 18 distributed on the outside of the rolling box 21, and an arc plate 23 is installed at the end of each fan-shaped plate 18. The arc plate 23 is arranged on the annular outer peripheral side of the rolling box 21, and each fan-shaped plate 18 is slidably connected to one side end surface of the rolling box 21. The fan-shaped plate 18 slides circumferentially along the central axis of the rolling box 21. When each fan-shaped plate 18 slides to the outside of the rolling box 21 and is evenly distributed, the outer side of the arc plate 23 can contact the tunnel ground to lift the side plate 3.

[0051] Through the above scheme, the present invention can move the arc plate 23 in the height adjustment mechanism 12 to be evenly distributed outside the rolling box 21 when the side panel 3 is moved. At this time, the side panel 3 is slightly lifted up to reduce the friction between the bottom of the side panel 3 and the support seat 7. In this way, the rolling effect of the rolling box 21 can be used when moving the side panel 3, making the construction more labor-saving and convenient.

[0052] As an optional embodiment of the present invention, a slider is installed on the inner side of the sector plate 18, and an annular groove 22 coaxially arranged therewith is provided on the outer surface of the rolling box 21, and the slider is slidably connected to the annular groove 22. A driving motor 19 is also fixed on the sector plate 18, and the output shaft of the driving motor 19 movably penetrates the sector plate 18 and is connected to a driving gear 28. An annular toothed plate 20 coaxial therewith is connected to the outer side of the rolling box 21, and the annular toothed plate 20 is meshed with the driving gear 28. The driving motor 19 can be used with an external power supply.

[0053] A convex plate 26 is also fixed on the outer side of the rolling box 21, and a through hole is opened on the convex plate 26. A fastening bolt spirally connected to the side plate 3 is installed at the through hole. A groove 24 is provided on one side of the rolling box 21 adjacent to the side plate 3, and a plurality of docking tubes 27 are distributed in the groove 24. When the rolling box 21 and the side plate 3 are fixed, the end of the docking tube 27 can dock with the outer port of the connecting tube 6 on the side plate 3. Specifically, a plurality of ventilation holes connected to the interior of the rolling box 21 are also opened on the side wall, so that gas can be further introduced into the tunnel.

[0054] In the present invention, when the side plate 3 is moved to a suitable position, the height adjustment mechanism 12 is reset, so that the bottom of the side plate 3 is stably contacted with the support seat 7 again, and then the rolling box 21 and the side plate 3 are fixed by fastening bolts passing through the convex plate 26.

[0055] Reference Figure 1 and Figure 2 The reinforcement structure proposed in the present invention also includes two protection boxes 9 respectively arranged on both sides of the hole, the outer ends of the outer conduit 4 all pass through the protection boxes 9, and a plurality of plug holes 101 are provided on the top plate 1, and a hollow reinforcing rod 11 is connected to the outer end of some of the plug holes 101, and the other end of the reinforcing rod 11 is connected to the outer end of the outer conduit 4, and the outer conduit 4, the protection box 9, the reinforcing rod 11 and the plug holes 101 are connected. Specifically, a communication hole 401 is provided on the outer conduit 4 located in the protection box 9, and the communication between the above structures is realized through the communication hole 401.

[0056] Through the above scheme, when the tunnel entrance collapses, water is injected into the protection box 9. At this time, since the outer conduit 4, the protection box 9, the reinforcing rod 11 and the socket 101 are connected, water can be transported into the tunnel, thereby rescuing the construction workers trapped in the tunnel.

[0057] Furthermore, a piston plate may be provided in the protection box 9, and a pressure plate 10 may be provided outside the protection box 9. The pressure plate and the piston plate are connected by a piston rod, which makes it more convenient to pressurize the water and facilitate the water flow into the tunnel.

[0058] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. The tunnel entrance section reinforcement structure is characterized by: It comprises several groups of support units and protection units tightly assembled in the tunnel, wherein the support unit comprises a top plate and two side plates, wherein the top plate is attached to the top of the inner wall of the tunnel, and the two side plates are attached to the two sides of the inner wall of the tunnel respectively, and the two side plates are detachably connected to the top plate, and the side plates are provided with several through holes along the height direction; The protection unit includes a plurality of outer conduits, each of which penetrates through holes at the same height on the side plate, and one end of the outer conduit is located outside the tunnel opening, and the other end of the outer conduit is located inside the tunnel and is covered with an inflatable and deflated air bag; The top surface of the side plate is provided with a plurality of rotation grooves, a bottom column is rotatably mounted at each rotation groove, a threaded groove is provided on the top surface of each bottom column, and a threaded rod is spirally mounted at the threaded groove, a top column is fixed to the top end of the threaded rod, a connecting head is fixed to the top end of the top column, a connecting seat that is engaged with the connecting head is connected to the bottom surface of the top plate, and the connecting seat and the connecting head are relatively fixed in the radial direction of the threaded rod; The outer side of the bottom column is sleeved with a fixing sleeve, and the top plate and the connecting seat are rotatably connected in the vertical direction through a hinge; A protective plate is fixed on the outer side of the side plate in the support unit near the tunnel entrance, a guide hole 1 is opened on the protective plate, a drill hole 1 is opened in the rock mass near the tunnel entrance along the guide hole 1, a plurality of guide holes 2 are also opened on the side plate, a plurality of drill holes 2 are opened on the inner wall of the tunnel along the guide holes 2, the drill holes 2 are all connected with the drill hole 1, an inner guide tube is inserted in the drill hole 1, a connecting pipe is inserted in the drill hole 2, and the end of the connecting pipe is plugged and connected with the inner guide tube; The inner conduit is provided with a plurality of docking holes, and the ends of the connecting pipes are inserted into the inner conduit through the docking holes. The outer wall of the outer end of the inner conduit is provided with a positioning ridge along the axial direction. The inner wall of the guide hole 1 is provided with a guide groove that cooperates with the positioning ridge. The outer wall of the inner conduit is provided with a plurality of elastic expansion rings, so that the inner conduit and the drill hole 1 are connected more tightly. It also includes two support seats symmetrically laid on the tunnel floor, the bottom surfaces of the two side panels are slidably connected to the two support seats respectively, and rolling boxes are rotatably installed on the adjacent sides of the two side panels, the bottom end height of the rolling box is higher than the bottom surface of the support seat, and a height adjustment mechanism is also arranged on the outer side of the rolling box, and the height adjustment mechanism can change the bottom surface height of the side panel; A center hole is opened at the center of the rolling box, and a center tube is movably inserted through the center hole. One end of the center tube is fixed to the side plate, and a limiting sleeve is installed at the other end of the center tube. The height adjustment mechanism includes a plurality of fan-shaped plates distributed on the outside of the rolling box, an arc plate is installed at the end of each fan-shaped plate, the arc plate is movably arranged on the annular outer peripheral side of the rolling box, and each fan-shaped plate is slidably connected to one side end face of the rolling box, and the fan-shaped plate slides circumferentially along the central axis of the rolling box. When each fan-shaped plate slides to the outside of the rolling box and is evenly distributed, the outer side of the arc plate can contact the tunnel ground to lift the side plate.

2. The tunnel entrance section reinforcement structure according to claim 1, characterized in that: A slider is installed on the inner side of the fan-shaped plate, and an annular groove coaxially arranged therewith is opened on the outer surface of the rolling box. The slider is slidably connected to the annular groove. A driving motor is also fixed on the fan-shaped plate. The output shaft of the driving motor movably passes through the fan-shaped plate and is connected to a driving gear. An annular gear plate coaxial with the rolling box is connected to the outer side of the rolling box, and the annular gear plate is meshed with the driving gear.

3. The tunnel entrance section reinforcement structure according to claim 1, characterized in that: A convex plate is also fixed on the outside of the rolling box, and a through hole is opened on the convex plate. A fastening bolt spirally connected to the side plate is installed at the through hole. A groove is provided on one side of the rolling box adjacent to the side plate, and a plurality of docking tubes are distributed in the groove. When the rolling box and the side plate are fixed, the end of the docking tube can dock with the outer port of the connecting tube on the side plate.

4. The tunnel entrance section reinforcement structure according to claim 3, characterized in that: It also includes two protection boxes respectively arranged on both sides of the hole, the outer ends of the outer conduits all pass through the protection boxes, and a number of sockets are opened on the top plate, some of the sockets are connected to the outer ends of the hollow reinforcing rods, the other end of the reinforcing rods is connected to the outer end of the outer conduit, and the outer conduit, the protection box, the reinforcing rods and the sockets are interconnected.

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