A new protection system for super-small clear distance parallel shield tunnel construction

Abstract

The application discloses a new protection system for super-small-clearance parallel shield tunnel construction and relates to the technical field of shield construction, which comprises the following construction steps: step one, completing the construction of a preceding tunnel; step two, constructing MJS isolation piles between the two tunnels; step three, forming a radial grouting reinforcement layer in the preceding tunnel; step four, synchronously arranging supporting equipment; step five, preparing for the entry of a shield tunneling machine and its matched equipment of a following tunnel; step six, forming a clay effect grouting filling layer; and step seven, forming a radial grouting reinforcement layer in the following tunnel. The application forms a complete protection system by using the innovative method of "MJS occlusive isolation wall+double-line tunnel grouting+preceding tunnel synchronous supporting+shield-outside clay effect grouting of a following line", and the method can be expanded to adapt to super-small-clearance shield multi-angle crossing engineering.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shield construction, in particular to a new protection system for super-small clear distance parallel shield tunnel construction. BACKGROUND

[0002] With the rapid development of underground space development in China, double-line parallel tunnels are favored in engineering projects, and due to limited space, the distance between the two tunnels is getting smaller and smaller, and parallel tunnels with a distance of less than 0.5D are becoming more common. Due to the small distance between the two tunnels, the secondary disturbance problem is serious, which not only causes the superposition of stratum loss and the increase of settlement, but also causes severe impact on the structure of the first-line tunnel during the construction of the second-line tunnel, aggravating the problems of the first-line tunnel such as cracking, longitudinal uneven deformation, seepage water and other diseases, affecting the construction quality and service performance. However, the construction technology and reinforcement technology for super-small clear distance parallel tunnel shield construction are not systematic, the reinforcement range and parameters do not consider the engineering cost, and lack of scientificity; in addition, the existing technology has a large size of the support trolley, which requires a large amount of manpower to move, hoist and fix and position, which is time-consuming and labor-intensive.

[0003] Therefore, there is an urgent need to invent a new protection system for super-small clear distance parallel tunnel shield construction, which can not only ensure the safety and quality of construction and ensure the economic and reasonable construction progress, but also has scientificity and intelligence, and reduces the use of manpower. SUMMARY

[0004] The purpose of the present application is to overcome the defects of the prior art, provide a new protection system for super-small clear distance parallel tunnel shield construction, and to ensure the safety and quality of construction, and to safely and efficiently organize construction by innovating the construction method, equipment and concept of super-small clear distance parallel tunnel shield construction, and to ensure the construction progress.

[0005] To achieve the above purpose, the present application provides the following technical scheme: a new protection system for super-small clear distance parallel shield tunnel construction, comprising the following construction steps:

[0006] Step 1: first construct one side of the small clear distance parallel tunnel, the shield machine penetrates from one side of the starting well to the receiving well, and the first-line tunnel construction is completed;

[0007] Step 2: MJS isolation piles are constructed between the two tunnels, the cross section of the MJS isolation pile is a semicircular column with a diameter of 2400mm, the MJS isolation pile is arranged along the tunnel axis direction, the pile center distance of adjacent MJS isolation piles is 1.5m-2m, the adjacent two piles are arranged in close contact to form an isolation wall; the length direction of the MJS isolation pile extends from 3m above the tunnel to 3m below the tunnel and is a solid pile body, the MJS isolation pile contains P.042.5 ordinary portland cement, the cement content is not less than 40% by mass fraction, and the water-cement ratio is 1.0;

[0008] Step three: after the MJS isolation pile construction is completed, the grouting trolley enters the first tunnel, and the sleeve valve pipe deep hole grouting reinforcement is carried out on the first tunnel through the grouting hole and the hoisting hole, the grouting range is 2m in diameter, the slurry adopts cement-sodium silicate double liquid slurry, the volume ratio of cement slurry to sodium silicate is 1:1; the sodium silicate is diluted with water, the dilution ratio of sodium silicate and water is 1:3 by volume; the water-cement ratio of cement slurry is 1:1, the grouting pressure is 0.5Mpa-1Mpa, and the radial grouting reinforcement layer in the first tunnel is formed;

[0009] Step four: after the deep hole grouting reinforcement treatment of the first tunnel is completed, the construction trolley is withdrawn from the first tunnel, and the synchronous supporting equipment is put into the tunnel;

[0010] Step five: after the shield machine and its supporting equipment of the second tunnel are put into the preparation, the construction conditions are met, the second tunnel construction is carried out, and at the same time, the synchronous supporting equipment in the first tunnel and the shield machine of the second line are synchronized to ensure that the first tunnel is supported at the position of the six rings of the cutter head of the second line;

[0011] Step six: with the construction of the second tunnel, the clay injection grouting is used in the position of the second line shield to form a clay injection grouting filling layer to fill the over-excavated stratum of the cutter head in the first time;

[0012] Step seven: when the segment assembly of the second tunnel is completed and there is a working space, the grouting trolley enters the second tunnel to carry out deep hole grouting on the second tunnel to form a radial grouting reinforcement layer in the second tunnel.

[0013] As a further scheme of the application: the synchronous supporting equipment includes two or more independent supporting units, and each independent supporting unit is connected through a universal electric telescopic rod; the synchronous supporting equipment includes an upper support and a lower support, and electric rollers are installed on the outer peripheral walls of the upper support and the lower support; the synchronous supporting equipment is provided with a reinforcing mechanism, and the reinforcing mechanism is installed between the upper support and the lower support; the upper support and the lower support are connected through a connecting mechanism, the reinforcing mechanism includes a reinforcing rod and a reinforcing frame, the reinforcing rod and the reinforcing frame are located in the inner cavity of the synchronous supporting equipment, the inner wall of the synchronous supporting equipment is provided with a slot, the inner wall of the slot is provided with a positioning groove, the reinforcing rod is slidably connected to the inner wall of the reinforcing frame, a positioning block extending to the outer wall of the reinforcing rod is slidably connected to the inside of the reinforcing rod, a first threaded rod extending to the inside of the positioning block is rotatably connected to the inside of the reinforcing rod, one end of the first threaded rod is fixedly connected with a first bevel gear, a second bevel gear is rotatably connected to the outer wall of the first bevel gear in the inside of the reinforcing rod, one end of the second bevel gear is fixedly connected with a connecting shaft, and one end of the connecting shaft is fixedly connected with a rotating block.

[0014] As a further further scheme of the present application: the reinforcing mechanism further comprises a docking groove, the docking groove is opened in one end of the reinforcing rod, the rotating block is located in the docking groove, the outer wall of the reinforcing frame is provided with a mounting groove, the inner wall of the mounting groove is slidably connected with a mounting frame, the inside of the reinforcing frame is slidably connected with a docking block extending into the inner cavity of the mounting groove, the bottom end of the docking block is fixedly connected with a limiting block, and the limiting block and the reinforcing frame are connected with a spring.

[0015] As a further further scheme of the present application: the connecting mechanism comprises a connecting groove, the connecting groove is opened at the top end of the lower support, the inner wall of the connecting groove is provided with a fixed groove, the bottom end of the upper support is fixedly connected with a connecting block, the inside of the connecting block is symmetrically slidably connected with a fixed block extending to the outer wall of the connecting block, one end of the fixed block is rotatably connected with a connecting rod, one end of the connecting rod is rotatably connected with a displacement block, the displacement block is slidably connected in the inside of the connecting block, the inside of the connecting block is rotatably connected with a second threaded rod extending into the inside of the displacement block, and one end of the second threaded rod is fixedly connected with a rotating column.

[0016] As a further further scheme of the present application: the outer wall of the reinforcing rod is fitted with the inner wall of the insertion groove, and the outer wall of the positioning block is fitted with the inner wall of the positioning groove.

[0017] As a further further scheme of the present application: the first bevel gear is engaged with the second bevel gear, the outer wall of the positioning block is provided with a first threaded hole, and the first threaded hole is matched with the first threaded rod.

[0018] As a further further scheme of the present application: the inner wall of the mounting groove is fitted with the outer wall of the mounting frame, the outer wall of the docking block is fitted with the inner wall of the docking groove, one end of the docking block located in the inner cavity of the mounting groove is provided with an inclined surface, and the shape of the docking block is Y-shaped; insertion grooves are opened at the four top corners of the reinforcing frame, and the docking block extends into the insertion grooves.

[0019] As a further further scheme of the present application: the outer wall of the mounting frame is provided with a first through hole, the inner cavity of the mounting groove is provided with a second through hole, the inner walls of the first through hole and the second through hole are slidably connected with a bolt, and the outer wall of the bolt is connected with a nut.

[0020] As a further further scheme of the present application: the inner wall of the connecting groove is fitted with the outer wall of the connecting block, and the inner wall of the fixed groove is fitted with the outer wall of the fixed block.

[0021] As a further further scheme of the present application: the both ends of the connecting rod are connected with the fixed block and the displacement block through rotating shafts, the outer wall of the displacement block is provided with a second threaded hole, and the second threaded hole is matched with the second threaded rod.

[0022] Compared with the prior art, the present application has the advantages that:

[0023] 1、The present application is a set of methods of "MJS occlusion isolation wall + double-line hole grouting + leading tunnel synchronous support + trailing line shield outside clay effect grouting", which forms a complete protection system and can be expanded to adapt to super-small clearance shield multi-angle crossing engineering, considering all aspects such as reducing disturbance source, strengthening transmission medium strength, blocking deformation transmission path, increasing disturbance object ring and longitudinal stiffness, forming a complete new protection system for parallel tunnel shield construction, and can also be expanded to adapt to super-small clearance shield multi-angle crossing engineering.

[0024] 2、Shield construction is a disturbance source, soil is a transmission medium, and the leading tunnel is a disturbance object, and the present application reduces the shield construction disturbance source, strengthens the transmission medium strength, blocks the deformation transmission path, and increases the disturbance object ring and longitudinal stiffness as the principle.

[0025] The MJS isolation pile in step two has a reinforcement range of 3m above the tunnel to 3m below the tunnel, which has been demonstrated to ensure isolation of disturbance load and save engineering cost.

[0026] The deep hole grouting reinforcement depth in steps three and seven is 2m, which has been demonstrated to ensure strengthening of the transmission medium strength and saving of engineering cost.

[0027] The synchronous support equipment in steps four and five has functions such as servo precise control, automatic walking, large-angle climbing, small curve turning, etc., which can effectively enhance the ring and longitudinal stiffness of the leading tunnel, and avoid the influence of additional load of the trailing line on the structure of the leading tunnel.

[0028] The trailing line shield outside clay effect grouting technology in step six can simultaneously fill the stratum overbreak loss caused by the shield cutter head and attitude, make up for the lag problem of synchronous grouting, and in addition, the disturbance caused by parallel shield construction will be superimposed, and the clay effect grouting can timely control the stratum deformation around the shield, and reduce the second disturbance of the stratum caused by the excavation of the trailing line.

[0029] 3、The use of the synchronous support equipment in step five ensures that the leading tunnel has support at the six-ring position in front of the trailing line cutter head (including the cutter head ring), and the six-ring range is a strong influence area, and the present application can strengthen the structure stiffness in this range. The synchronous support equipment can automatically walk, and the leading tunnel structure is constrained in advance under additional load to ensure the safety of the leading tunnel structure during construction.

[0030] In addition, the synchronous support equipment is provided with multiple independent support units connected through universal electric telescopic rods, and the length of the support can be controlled by controlling the number of the independent support units connected according to the requirement; due to the universal electric telescopic rods, the flexible connection between the independent support units can be realized, so that the synchronous support equipment can adapt to different tunnel structure forms such as turning and climbing, and the adaptability is stronger; the independent support unit adopts a split structure, which is convenient for hoisting and carrying, and can realize real-time and rapid assembly operation in the tunnel, so that the labor and time consumption can be further saved, and the synchronous support equipment is more flexible and convenient to use.

[0031] In summary, the construction method of the application has a clever design concept, high construction efficiency, strong operability, good safety, friendly application environment and wide market prospect. The reinforcement range, parameters and methods of the application are scientific, systematic and intelligent, can avoid using a large amount of manpower, and can ensure construction safety, quality and progress. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The application flow chart of the novel protection system for super-small clear distance parallel tunnel shield construction of the application;

[0033] Figure 2 The longitudinal section schematic diagram of the novel protection system for super-small clear distance parallel tunnel shield construction of the application;

[0034] Figure 3 The transverse section structure schematic diagram of the novel protection system for super-small clear distance parallel tunnel shield construction of the application;

[0035] Figure 4 The structure schematic diagram of the synchronous support equipment of the application;

[0036] Figure 5 The structure schematic diagram of the independent support unit of the application;

[0037] Figure 6 The structure schematic diagram of the slot of the application;

[0038] Figure 7 The internal structure schematic diagram of the reinforcing rod of the application;

[0039] Figure 8 The installation schematic diagram of the mounting frame of the application;

[0040] Figure 9 The installation schematic diagram of the butt joint block of the application;

[0041] Figure 10 The connection schematic diagram of the upper support and the lower support of the application;

[0042] Figure 11The internal structure of the connecting block of the present application is shown in the diagram.

[0043] In the diagram: 1, preceding tunnel; 2, MJS isolation pile; 3, radial grouting reinforcement layer in preceding hole; 4, synchronous supporting equipment; 401, independent supporting unit; 402, upper support; 403, lower support; 404, universal electric telescopic rod; 5, following tunnel; 6, clay injection filling layer; 7, radial grouting reinforcement layer in following hole; 8, reinforcing mechanism; 801, reinforcing rod; 802, reinforcing frame; 803, insertion slot; 804, positioning slot; 805, positioning block; 806, first threaded rod; 807, first bevel gear; 808, second bevel gear; 809, connecting shaft; 810, rotating block; 811, butt joint slot; 812, mounting slot; 813, mounting frame; 814, butt joint block; 815, limiting block; 816, spring; 817, insertion slot; 9, connecting mechanism; 901, connecting slot; 902, fixed slot; 903, connecting block; 904, fixed block; 905, connecting rod; 906, displacement block; 907, second threaded rod; 908, rotating column; 10, first through hole; 11, second through hole; 12, bolt; 13, nut. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0045] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "setting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication between the two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. The embodiments of the present application will be described below according to the overall structure of the present application.

[0046] Referring to Figures 1 to 11 In the embodiment of the present application, a new protection system for super-small clear distance parallel shield tunnel construction comprises the following construction steps:

[0047] Step one: first construct one side tunnel of the small clear distance parallel tunnel, the shield machine penetrates from the starting well to the receiving well, and the first tunnel 1 is completed;

[0048] Step two: MJS isolation piles 2 are constructed between the two tunnels, the cross section of the MJS isolation piles 2 is a semicircular column with a diameter of 2400 mm, the MJS isolation piles 2 are arranged along the tunnel axis direction, the distance between the centers of adjacent MJS isolation piles 2 is 1.5-2 m, so that the adjacent two piles are arranged in close contact to form an isolation wall; the length direction of the MJS isolation piles 2 extends from 3 m above the tunnel to 3 m below the tunnel and is a solid pile body, the MJS isolation piles 2 contain P.042.5 grade ordinary portland cement, the cement content is not less than 40% by mass fraction, and the water-binder ratio is 1.0;

[0049] Step three: after the MJS isolation piles 2 are constructed, the grouting trolley enters the first tunnel 1, the sleeve valve pipe deep hole grouting reinforcement is carried out on the first tunnel 1 through the grouting hole and the hoisting hole, the grouting range is 2 m in the radial direction, the slurry adopts cement-sodium silicate double liquid slurry, the volume ratio of cement slurry to sodium silicate is 1:1; the sodium silicate is diluted with water, the dilution ratio of sodium silicate and water is 1:3 by volume; the water-cement ratio of the cement slurry is 1:1, the grouting pressure is 0.5-1 MPa, and the radial grouting reinforcement layer (3) in the first tunnel is formed;

[0050] Step four: after the deep hole grouting reinforcement treatment of the first tunnel 1 is completed, the construction trolley is withdrawn from the first tunnel 1, and the synchronous roof supporting equipment 4 enters the site and is located at the position needing to be supported on the first tunnel 1;

[0051] Step five: the shield machine and its supporting equipment of the following tunnel 5 enter the site for preparation, after the construction conditions are met, the following tunnel 5 is constructed and excavated, at the same time, the synchronous roof supporting equipment 4 on the first tunnel 1 and the shield machine of the following tunnel advance synchronously, so that the first tunnel 1 is supported at the position of the six rings of the cutter head of the following tunnel;

[0052] Step six: along with the construction of the following tunnel 5, the clay injection grouting is adopted at the position of the shield of the following tunnel to form the clay injection grouting filling layer 6, which fills the over-excavated stratum of the cutter head in the first time;

[0053] Step seven: when the segment assembly of the following tunnel 5 is completed and there is a working space, the grouting trolley enters the following tunnel 5 to carry out deep hole grouting on the following tunnel 5, and the radial grouting reinforcement layer 7 in the following tunnel is formed.

[0054] Please refer to Figures 4 to 11The synchronous supporting and top equipment 4 comprises two or more independent supporting unit bodies 401, each independent supporting unit body is connected through a universal electric telescopic rod 404, the synchronous supporting and top equipment 4 comprises an upper support 402 and a lower support 403, and electric rollers are mounted on the outer peripheral walls of the upper support 402 and the lower support 403; a reinforcing mechanism 8 is arranged in the synchronous supporting and top equipment 4, the reinforcing mechanism 8 is mounted between the upper support 402 and the lower support 403; and the upper support 402 and the lower support 403 are connected through a connecting mechanism 9.

[0055] The reinforcing mechanism 8 comprises a reinforcing rod 801 and a reinforcing frame 802, the reinforcing rod 801 and the reinforcing frame 802 are located in the inner cavity of the synchronous supporting and top equipment 4, a slot 803 is formed in the inner wall of the synchronous supporting and top equipment 4, a positioning slot 804 is formed in the inner wall of the slot 803, the reinforcing rod 801 is slidingly connected to the inner wall of the reinforcing frame 802, a positioning block 805 extending to the outer wall of the reinforcing rod 801 is slidingly connected to the inside of the reinforcing rod 801, a first threaded rod 806 extending to the inside of the positioning block 805 is rotationally connected to the inside of the reinforcing rod 801, one end of the first threaded rod 806 is fixedly connected with a first bevel gear 807, a second bevel gear 808 is rotationally connected to the outer wall of the first bevel gear 807 in the inside of the reinforcing rod 801, one end of the second bevel gear 808 is fixedly connected with a connecting shaft 809, one end of the connecting shaft 809 is fixedly connected with a rotating block 810, the reinforcing mechanism 8 further comprises a butt joint slot 811, the butt joint slot 811 is formed at one end of the reinforcing rod 801, the rotating block 810 is located in the butt joint slot 811, an installation slot 812 is formed in the outer wall of the reinforcing frame 802, an installation frame 813 is slidingly connected to the inner wall of the installation slot 812, a butt joint block 814 extending to the inner cavity of the installation slot 812 is slidingly connected to the inside of the reinforcing frame 802, a limiting block 815 is fixedly connected to the bottom end of the butt joint block 814, and a spring 816 is connected between the limiting block 815 and the reinforcing frame 802.

[0056] In the embodiment, when the single independent supporting unit body 401 of the synchronous supporting and top equipment 4 is assembled, the reinforcing mechanism is assembled first. The reinforcing mechanism is assembled in the following manner: the reinforcing rod 801 is inserted into the slot 803, after completion, the rotating block 810 is rotated, the rotating block 810 drives the connecting shaft 809 to rotate, the connecting shaft 809 drives the second bevel gear 808 to rotate, the second bevel gear 808 drives the first bevel gear 807 to rotate, the first bevel gear 807 drives the first threaded rod 806 to rotate, the first threaded rod 806 drives the positioning block 805 to displace, and the positioning block 805 is inserted into the positioning slot 804 to fix the reinforcing rod 801 in the slot 803.

[0057] Then the reinforcing frame 802 is placed into the inner cavity of the synchronous supporting equipment 4 (i.e. between the assembled upper support 402 and lower support 403), in contact with one end of the reinforcing rod 801, then the mounting frame 813 is mounted into the mounting slot 812, the mounting frame 813 is displaced to contact the abutting block 814, the abutting block 814 and the limiting block 815 are displaced to press the spring 816, the abutting block 814 is displaced out of the reinforcing frame 802 and inserted into the abutting slot 811, the reinforcing rod 801 and the reinforcing frame 802 are fixed, facilitating the assembly of the reinforcing mechanism in the synchronous supporting equipment 4.

[0058] Please refer to Figures 10 to 11 , the connecting mechanism 9 comprises a connecting slot 901, the connecting slot 901 is arranged at the top end of the lower support 403, the inner wall of the connecting slot 901 is provided with a fixing slot 902, the bottom end of the upper support 402 is fixedly connected with a connecting block 903, the inside of the connecting block 903 is symmetrically and slidably connected with a fixing block 904 extending to the outer wall of the connecting block 903, one end of the fixing block 904 is rotatably connected with a connecting rod 905, one end of the connecting rod 905 is rotatably connected with a displacement block 906, the displacement block 906 is slidably connected in the inside of the connecting block 903, the inside of the connecting block 903 is rotatably connected with a second threaded rod 907 extending to the inside of the displacement block 906, one end of the second threaded rod 907 is fixedly connected with a rotating column 908.

[0059] In this embodiment: when connecting the upper support 402 and the lower support 403, the connecting block 903 is inserted into the connecting slot 901, after completion, the rotating column 908 is rotated, the rotating column 908 drives the second threaded rod 907 to rotate, the second threaded rod 907 drives the displacement block 906 to displace, the displacement block 906 displaces the fixing block 904 through the connecting rod 905, the fixing block 904 is displaced and inserted into the fixing slot 902, thereby fixing and connecting the upper support 402 and the lower support 403, facilitating the installation operation of the synchronous supporting equipment 4;

[0060] It is worth noting that the electric rollers are installed on the outer peripheral wall of the synchronous supporting equipment 4, i.e. on the outer peripheral wall of the upper support 402 and the lower support 403, which are electric rollers for moving the synchronous supporting equipment 4. The electric rollers are anti-pressure electric rollers that can be remotely started, stopped and speed-adjusted.

[0061] Please refer to Figures 5 to 7 , the outer wall of the reinforcing rod 801 is fitted with the inner wall of the insertion slot 803, the outer wall of the positioning block 805 is fitted with the inner wall of the positioning slot 804, the first bevel gear 807 is engaged with the second bevel gear 808, the outer wall of the positioning block 805 is provided with a first threaded hole, and the first threaded hole is matched with the first threaded rod 806.

[0062] In the embodiment, the reinforcing rod 801 is inserted into the slot 803, after the operation, the rotating block 810 is rotated, the rotating block 810 drives the connecting shaft 809 to rotate, the connecting shaft 809 drives the second bevel gear 808 to rotate, the second bevel gear 808 drives the first bevel gear 807 to rotate, the first bevel gear 807 drives the first threaded rod 806 to rotate, the first threaded rod 806 drives the positioning block 805 to displace, the positioning block 805 is inserted into the positioning groove 804, and the reinforcing rod 801 is fixed in the slot 803.

[0063] Please refer to Figures 7 to 9 , the inner wall of the mounting groove 812 is attached to the outer wall of the mounting frame 813, the outer wall of the abutting block 814 is attached to the inner wall of the abutting groove 811, the abutting block 814 is provided with an inclined surface at one end of the inner cavity of the mounting groove 812, and the shape of the abutting block 814 is Y-shaped; the slot 817 is arranged at the four top corners of the reinforcing frame 802, and the abutting block 814 extends into the slot 817.

[0064] In the embodiment, the mounting frame 813 is mounted into the mounting groove 812, the mounting frame 813 is displaced to contact the abutting block 814, the abutting block 814 and the limiting block 815 are displaced to press the spring 816, the abutting block 814 is inserted into the abutting groove 811 after passing through the slot 817 and moving out of the reinforcing frame 802, and the reinforcing rod 801 and the reinforcing frame 802 are fixed.

[0065] Please refer to Figure 8 , the outer wall of the mounting frame 813 is provided with a first through hole 10, the inner cavity of the mounting groove 812 is provided with a second through hole 11, the inner walls of the first through hole 10 and the second through hole 11 are slidably connected with a bolt 12, and the outer wall of the bolt 12 is connected with a nut 13.

[0066] In the embodiment, after the mounting frame 813 is moved into the mounting groove 812, the bolt 12 passes through the first through hole 10 and the second through hole 11, the nut 13 is connected to the outer wall of the bolt 12, and the bolt 12 and the nut 13 fix the mounting frame 813 in the mounting groove 812.

[0067] Please refer to Figures 10 to 11 , the inner wall of the connecting groove 901 is attached to the outer wall of the connecting block 903, and the inner wall of the fixing groove 902 is attached to the outer wall of the fixing block 904.

[0068] In the embodiment, the connecting block 903 is inserted into the connecting groove 901, after the operation, the rotating column 908 is rotated, the fixing block 904 is displaced and inserted into the fixing groove 902, so that the upper support 402 and the lower support 403 are fixedly connected.

[0069] Please refer to Figures 10 to 11The two ends of the connecting rod 905 are connected with the fixed block 904 and the displacement block 906 through rotating shafts, and the outer wall of the displacement block 906 is provided with a second threaded hole matched with a second threaded rod 907.

[0070] In the embodiment, the rotating column 908 is rotated, the rotating column 908 drives the second threaded rod 907 to rotate, the second threaded rod 907 drives the displacement block 906 to displace, and the displacement block 906 drives the fixed block 904 to displace through the connecting rod 905.

[0071] The above is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A new protection system for ultra-small clear distance parallel shield tunnel construction, characterized in that, The construction steps include: Step one: firstly, one of the small-pitch parallel tunnels is constructed, a shield machine is launched from a side starting shaft and penetrates to a receiving shaft, and a first tunnel (1) is constructed; Step two: MJS isolation piles (2) are constructed between the two tunnels, the cross section of the MJS isolation piles (2) is a semicircular column with a diameter of 2400 mm, the MJS isolation piles (2) are arranged along the tunnel axis, the distance between the centers of adjacent MJS isolation piles (2) is 1.5-2 m, the adjacent two piles are arranged to be in close contact to form an isolation wall, the length direction of the MJS isolation piles (2) extends from 3 m above the tunnel to 3 m below the tunnel and is a solid pile body, the MJS isolation piles (2) contain P.042.5 ordinary portland cement, the cement content is not less than 40% by mass fraction, and the water-binder ratio is 1.0; Step three: after the MJS isolation piles (2) are constructed, a grouting trolley enters the first tunnel (1), a sleeve valve pipe deep hole grouting reinforcement is performed on the first tunnel (1) through a grouting hole and a hoisting hole, the grouting range is 2 m in the radial direction, a cement-silicate double liquid grout is used for the grout, the volume ratio of the cement grout to the silicate is 1:1, the silicate is diluted with water, the dilution ratio of the silicate to water is 1:3 by volume, the water-cement ratio of the cement grout is 1:1, the grouting pressure is 0.5-1 MPa, and a radial grouting reinforcement layer (3) in the first tunnel is formed; Step four: after the deep hole grouting reinforcement treatment of the first tunnel (1) is completed, a construction trolley is withdrawn from the first tunnel (1), a synchronous roof supporting equipment (4) enters the site, and is located at a position needing to be supported in the first tunnel (1); Step five: a shield machine and its matched equipment of a subsequent tunnel (5) enter the site for preparation, after the construction conditions are met, the subsequent tunnel (5) is constructed and excavated, at the same time, the synchronous roof supporting equipment (4) and the shield machine of the subsequent tunnel are advanced synchronously, and the first tunnel (1) is supported at positions six rings away from the cutter head of the subsequent tunnel; Step six: along with the construction of the subsequent tunnel (5), a clay injection grouting filling layer (6) is formed in the subsequent tunnel, and the clay injection grouting filling layer (6) fills the stratum excavated by the cutter head in the first time; Step seven: when the segment assembly of the subsequent tunnel (5) is completed and there is a working space, a grouting trolley enters the subsequent tunnel (5), a deep hole grouting is performed on the subsequent tunnel (5), and a radial grouting reinforcement layer (7) in the subsequent tunnel is formed; The synchronous roof supporting equipment (4) includes two or more independent supporting units (401), the independent supporting units are connected through universal electric telescopic rods (404), the synchronous roof supporting equipment (4) includes an upper support (402) and a lower support (403), electric rollers are installed on the outer peripheral walls of the upper support (402) and the lower support (403), a reinforcing mechanism (8) is arranged in the synchronous roof supporting equipment (4), the reinforcing mechanism (8) is installed between the upper support (402) and the lower support (403), and the upper support (402) and the lower support (403) are connected through a connecting mechanism (9). The reinforcing mechanism (8) comprises a reinforcing rod (801) and a reinforcing frame (802), the reinforcing rod (801) and the reinforcing frame (802) are located in the inner cavity of the synchronous supporting equipment (4), the inner wall of the synchronous supporting equipment (4) is provided with a slot (803), the inner wall of the slot (803) is provided with a positioning groove (804), the reinforcing rod (801) is slidably connected to the inner wall of the reinforcing frame (802), the inner part of the reinforcing rod (801) is slidably connected with a positioning block (805) extending to the outer wall of the reinforcing rod (801), the inner part of the reinforcing rod (801) is rotatably connected with a first threaded rod (806) extending to the inner part of the positioning block (805), one end of the first threaded rod (806) is fixedly connected with a first bevel gear (807), the inner part of the reinforcing rod (801) is rotatably connected with a second bevel gear (808) on the outer wall of the first bevel gear (807), one end of the second bevel gear (808) is fixedly connected with a connecting shaft (809), one end of the connecting shaft (809) is fixedly connected with a rotating block (810).

2. The new protection system for ultra-small clear distance parallel shield tunnel construction according to claim 1, characterized in that, The reinforcing mechanism (8) further comprises a butt joint groove (811), the butt joint groove (811) is arranged at one end of the reinforcing rod (801), the rotating block (810) is located in the butt joint groove (811), the outer wall of the reinforcing frame (802) is provided with a mounting groove (812), the inner wall of the mounting groove (812) is slidably connected with a mounting frame (813), the inner part of the reinforcing frame (802) is slidably connected with a butt joint block (814) extending to the inner cavity of the mounting groove (812), the bottom end of the butt joint block (814) is fixedly connected with a limiting block (815), the limiting block (815) and the reinforcing frame (802) are connected with a spring (816).

3. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 2, characterized in that, The connecting mechanism (9) comprises a connecting groove (901), the connecting groove (901) is arranged at the top end of the lower support (403), the inner wall of the connecting groove (901) is provided with a fixing groove (902), the bottom end of the upper support (402) is fixedly connected with a connecting block (903), the inner part of the connecting block (903) is symmetrically slidably connected with a fixing block (904) extending to the outer wall of the connecting block (903), one end of the fixing block (904) is rotatably connected with a connecting rod (905), one end of the connecting rod (905) is rotatably connected with a displacement block (906), the displacement block (906) is slidably connected to the inner part of the connecting block (903), the inner part of the connecting block (903) is rotatably connected with a second threaded rod (907) extending to the inner part of the displacement block (906), one end of the second threaded rod (907) is fixedly connected with a rotating column (908).

4. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 2, characterized in that, The outer wall of the reinforcing rod (801) is fitted with the inner wall of the slot (803), and the outer wall of the positioning block (805) is fitted with the inner wall of the positioning groove (804).

5. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 2, characterized in that, The first bevel gear (807) is engaged with the second bevel gear (808), the outer wall of the positioning block (805) is provided with a first threaded hole matched with the first threaded rod (806).

6. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 2, characterized in that, The inner wall of the mounting groove (812) is attached to the outer wall of the mounting frame (813), the outer wall of the butt joint block (814) is attached to the inner wall of the butt joint groove (811), the butt joint block (814) is provided with an inclined surface at one end of the inner cavity of the mounting groove (812), and the butt joint block (814) is Y-shaped; the reinforcing frame (802) is provided with a slot (817) at four corners, and the butt joint block (814) extends into the slot (817).

7. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 2, characterized in that, The outer wall of the mounting frame (813) is provided with a first through hole (10), the inner cavity of the mounting groove (812) is provided with a second through hole (11), the inner walls of the first through hole (10) and the second through hole (11) are slidably connected with a bolt (12), and the outer wall of the bolt (12) is connected with a nut (13).

8. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 3, characterized in that, The inner wall of the connecting groove (901) is attached to the outer wall of the connecting block (903), and the inner wall of the fixing groove (902) is attached to the outer wall of the fixing block (904).

9. The new protection system for super-small clear distance parallel shield tunnel construction according to claim 3, characterized in that, Both ends of the connecting rod (905) are connected with the fixing block (904) and the displacement block (906) through rotating shafts, and the outer wall of the displacement block (906) is provided with a second threaded hole matched with the second threaded rod (907).

Images