Large-diameter shield ventilation shaft system

Abstract

The utility model provides a large-diameter shield air shaft passing system which comprises a steel-concrete prefabricated pedestal and a shield machine arranged on the upper portion of the steel-concrete prefabricated pedestal, the central axis of the steel-concrete prefabricated pedestal is consistent with the central axis of an air shaft, and the top face of the steel-concrete prefabricated pedestal is provided with a central pre-buried steel support in a full-length mode along the central axis. Side embedded steel supports are symmetrically arranged along the two sides of the center embedded steel support in a full-length mode, the first section of the steel-concrete prefabricated pedestal abuts against the enclosure wall, and the tail section of the steel-concrete prefabricated pedestal abuts against the starting support. The construction method has the construction advantages of high stability, high efficiency, high benefit and the like during implementation, and the technical benefit is remarkable.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of tunnel engineering especially relates to large diameter shield constructs over wind well system. BACKGROUND

[0002] Under the background of increasing density of urban rail transit lines, due to the limitation of planning and existing buildings, the line shape of urban rail transit is increasingly complex, in order to avoid the influence of buildings and ensure the ventilation requirement of long interval tunnel, the plane line type of the intermediate air shaft set in the long subway tunnel is usually designed as a small radius curve, which causes the existence of angle between the direction of shield entering and exiting the air shaft, and increases the construction difficulty of shield passing through the air shaft.

[0003] The current commonly used passing station mode of shield machine mainly includes air pushing jacking passing station, shield disassembly passing station and whole machine translation passing station schemes. Among them, the shield disassembly passing station mode re-connects the pipeline after completing translation and carries out debugging, causing the extension of construction period; the whole machine translation passing station must use special passing station jacking equipment for shield translation, and steel pipe support and track must be simultaneously erected in the working well, which is complicated and difficult to construct, and the safety risk is high; in addition to the above schemes, the foam concrete hole entering and exiting process can also realize the rapid passing station of shield, but its cost is high and the preparation work before passing station takes a long time. Therefore, the air pushing jacking passing station is particularly prominent in construction period and cost, but the air pushing jacking passing station technology is difficult, and the guide table structure design and negative ring segment reinforcement treatment are particularly important.

[0004] There is a Chinese utility model patent application No. 201720663590.5 which discloses a guide table structure for facilitating the passing of shield machine through the intermediate air shaft. The guide table structure effectively enhances the stability and bearing capacity of the whole structure by setting the transverse steel plate, left side fixed body and steel bar system; at the same time, the steel sheet structure is set to prevent accidental side sliding of the shield machine, and the anti-explosion nut is also set to prevent the explosion of the concrete inside the guide table due to the excessive weight of the shield machine. However, the whole guide table structure of this patent only improves its bearing performance and construction stability, and does not effectively improve the construction efficiency of the guide table in the air shaft and the guide rail installation process.

[0005] In addition, a Chinese utility model patent application No. 201911334729.1 discloses a shield machine passing air shaft device and its construction method, which simply combines the support structure, anti-sliding structure, connecting structure and pre-buried structure, optimizes the operation scheme and operation process of the traditional shield machine passing air shaft, shortens the construction period of the shield machine passing air shaft link, solves the problem of tunnel linearity, realizes the adjustment of tunnel linearity, and ensures that the shield machine passing air shaft device has sufficient bearing capacity and anti-deviation capacity. However, this patent mainly solves the problem of guide table linearity through pre-buried components and cast-in-place concrete process, and does not optimize the air pushing device and the reinforcement of negative ring segments.

[0006] Therefore, there is an urgent need for a large-diameter shield overwind shaft system construction method with fast construction speed, high construction safety and prominent economic and technical benefits. Content of the utility model

[0007] The utility model aims at providing a large-diameter shield overwind shaft system which solves the above technical problems.

[0008] To solve the above technical problems, the utility model provides a large-diameter shield overwind shaft system, which comprises a steel-concrete prefabricated pedestal and a shield machine arranged on the upper portion of the steel-concrete prefabricated pedestal.

[0009] Further, guide rails are installed on the side embedded steel supports and the center embedded steel support, and a concrete formwork is installed on the upper portion of the steel-concrete prefabricated pedestal to enable the concrete formwork to perform the cast-in-place concrete area.

[0010] Further, the shell of the shield machine is connected with a steel plate and a roller assembly, an electric control reaction support is installed on the shield tail, a reaction support seat type steel frame and a roller hydraulic pusher are installed on the guide rails, and a hydraulic push rod is arranged between the reaction support seat type steel frame and the electric control reaction support to enable the hydraulic push rod and the roller hydraulic pusher to be pushed alternately.

[0011] Further, a reaction frame is arranged in the wind shaft, and a plurality of negative ring segments are assembled and connected between the reaction frame and the shield jacks.

[0012] Further, an arc-shaped water stop steel plate is arranged on the embedded steel ring of the enclosure wall, transverse arc-shaped braces are symmetrically installed on both sides of the negative ring segment, and the outer side of the negative ring segment is tightly clamped by the steel wire rope of the prestressed tensioner.

[0013] Further, the guide rails are connected perpendicularly to the top surfaces of the center embedded steel support and the side embedded steel support.

[0014] Further, an electric control limiting device is arranged in the center of the reaction support seat type steel frame, limiting wing plates are symmetrically arranged on both sides, and the limiting wing plates are arranged on both sides of the guide rails.

[0015] Further, the center of the roller hydraulic pusher is provided with an electric control limiting device, and the electric control limiting device of the roller hydraulic pusher and the center electric control limiting device of the counterforce support seat type steel frame are connected with the electric control counterforce support through a circuit.

[0016] Further, the arc-shaped water stop steel plate includes symmetrically arranged upper and lower arc-shaped water stop steel plates, and the upper and lower arc-shaped water stop steel plates are perpendicular to the embedded steel ring.

[0017] Further, the lateral arc-shaped support plate is provided with an adjustable hydraulic support at the side, the bottom of the adjustable hydraulic support is in abutment with the side enclosure wall, at least two prestressed tensioners are symmetrically arranged on both sides of the starting support, and the steel wire rope is connected to the at least two prestressed tensioners after being wound around the outer periphery of the negative ring segment.

[0018] The beneficial effects of the utility model lie in:

[0019] (1) The utility model discloses a steel-concrete prefabricated pedestal shield air shaft passing station foundation structure. Through the steel-concrete prefabricated pedestal and the embedded steel support structure, the process of the existing guide table structure site mass concrete layering pouring is avoided, the setting precision of the steel support is improved, and the whole can be customized according to the curvature of the air shaft central axis, so that the site construction period is shortened, and the shield air shaft passing station foundation quality is effectively improved.

[0020] (2) The utility model provides a counterforce support seat integrated electric control hydraulic pushing technology. Through the electric control counterforce support in the shield tail, the counterforce support seat type steel frame on the guide rail and the roller hydraulic pusher, efficient and alternating pushing in the air shaft is realized, the shield posture dynamic adjustment is realized, installation is convenient, and the intelligent degree is high.

[0021] (3) The utility model optimizes the internal and external synchronous reinforcement technology of the negative ring segment. The internal whole is reinforced by using a steel reinforcing member, the external combination adopts a lateral arc-shaped support plate and a prestressed steel wire rope for reinforcement, the prestressed tensioner is arranged in the starting support to realize the circumferential clamping of the steel wire rope to the negative ring segment, and the overall stability and safety of the shield secondary starting are greatly improved. DRAWINGS

[0022] Figure 1 It is a longitudinal section view of the utility model shield machine empty pushing through the air shaft.

[0023] Figure 2 It is a schematic view of the utility model counterforce support seat type steel frame structure.

[0024] Figure 3 It is a transverse section view of the utility model shield machine empty pushing through the air shaft.

[0025] Figure 4 It is a schematic view of the utility model steel-concrete prefabricated pedestal structure.

[0026] Figure 5 This is a schematic diagram of the guide rail installation of the utility model;

[0027] Figure 6 This is a diagram showing the relationship between the position of the cast-in-place concrete and the guide rails of the present invention;

[0028] Figure 7 This is a schematic diagram of the negative ring segment reinforcement of the utility model;

[0029] Figure 8 This is a cross-sectional view of the installation of the arc-shaped water-stop steel plate of the utility model;

[0030] Figure 9 This is a cross-sectional view of the installation of the arc-shaped water-stop steel plate of the utility model;

[0031] Figure 10 It is a schematic diagram of the closed soil box structural system of the utility model.

[0032] In the figure: 1. Soil in the reinforcement area; 2. Retaining wall; 3. Embedded steel ring; 4. Shield machine; 5. First connecting bolt; 6. Hinge plate; 7. Rubber curtain plate; 8. Segment; 9. Electric limit device; 10. Reaction support seat steel frame; 11. Hydraulic jacking rod; 12. Steel-concrete precast pedestal; 13. Roller hydraulic jacking device; 14. Electric reaction support; 15. Roller assembly; 16. Guide rail; 17. Side embedded steel support; 18. Cast-in-place concrete; 1 9. Limiting wing plate; 20. Central embedded steel support; 21. Negative ring segment; 22. Arc support plate; 23. Second connecting bolt; 24. Steel reinforcement; 25. Adjustable hydraulic support; 26. Steel wire rope; 27. Starting support; 28. Prestressed tensioner; 29. ​​Upper arc-shaped waterstop steel plate; 30. Lower arc-shaped waterstop steel plate; 31. Plain soil backfill layer; 32. Temporary support; 33. Plastic improved soil backfill layer; 34. Gravel backfill layer; 35. Tunnel portal. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0034] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms cannot be understood as limiting the present invention.

[0035] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the elements may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0036] like Figures 1-10 As described above, the utility model provides a large-diameter shield tunneling system, and the following steps can be adopted during its construction:

[0037] S1. Measurement and layout, installation of the steel-concrete prefabricated pedestal 12: Determine the axis point and the limit points on both sides of the steel-concrete prefabricated pedestal 12 through online measurement and layout. After verification, transport the steel-concrete prefabricated pedestal 12 in batches to the ventilation shaft for installation. After installation, the central axis of the steel-concrete prefabricated pedestal 12 is consistent with the central axis of the ventilation shaft.

[0038] In the steps, Figure 4 As shown, a central embedded steel support 20 is provided on the top surface of the steel-concrete prefabricated pedestal 12 along the entire length of the central axis, and side embedded steel supports 17 are symmetrically provided along both sides of the central embedded steel support 20. The first section of the steel-concrete prefabricated pedestal 12 abuts against the retaining wall 2, and the last section abuts against the starting bracket 27.

[0039] The retaining wall 2 is arranged on the side of the soil 1 in the reinforcement area.

[0040] S2. Guide rail 16 assembly and concrete formwork construction: Install the guide rail 16 assembly on the side embedded steel support 17 and the center embedded steel support 20. After verifying the concrete formwork axis and elevation position, install the concrete formwork on the upper part of the steel-concrete prefabricated pedestal 12. The concrete formwork is all customized steel formwork.

[0041] In this step, if Figure 5 As shown, the guide rail 16 is welded perpendicular to the top surfaces of the central embedded steel support 20 and the side embedded steel support 17 .

[0042] S3. Construction of cast-in-place concrete 18: After the concrete formwork has been fully inspected and qualified, the cast-in-place concrete 18 area is poured at one time and vibrated using an attached vibrator installed on the concrete formwork. After curing, the formwork is demoulded and the portion of the guide rail 16 exposed to the cast-in-place concrete 18 is polished and cleaned.

[0043] In this step, if Figure 6 As shown, the base of the guide rail 16 is completely embedded in the cast-in-place concrete 18.

[0044] If there is a water-rich pebble layer geological condition that does not meet the air-pushing technical conditions, a crushed stone backfill layer 34 is used to replace the cast-in-place concrete 18 on the basis of the steel-concrete prefabricated pedestal 12, and after a temporary support 32 is arranged in the air shaft in an annular direction, the plastic improved soil backfill layer 33 is continued to be constructed to the top of the shield crossing area, and finally the plain soil backfill layer 31 is constructed to the groundwater level to form a closed soil box structure system. Figure 10 As shown, the shield machine 4 can tunnel normally through the ventilation shaft.

[0045] S4. A guide platform is designed on the shield machine 4 to push the shield machine 4 through the ventilation shaft: after the front body of the shield machine 4 escapes from the steel ring of the tunnel portal 35, the shell of the shield machine 4 is gradually welded with steel plates and roller assemblies 15, and an electrically controlled reaction support 14 is installed at the shield tail. The reaction support seat steel frame 10 and the roller hydraulic pusher 13 are simultaneously installed on the guide rail 16. Subsequently, a hydraulic push rod 11 is set up between the reaction support seat steel frame 10 and the electrically controlled reaction support 14. The electrically controlled limit device 9 is used to realize the alternating pushing of the hydraulic push rod 11 and the roller hydraulic pusher 13, and the shield posture is dynamically adjusted to complete the push of the shield machine 4 through the ventilation shaft.

[0046] Alternating pushing process: the electric control limit device 9 of the reaction support seat steel frame 10 is opened, the electric control limit device 9 of the roller hydraulic pusher 13 is closed, and the hydraulic push rod 11 pushes forward → the electric control limit device 9 of the reaction support seat steel frame 10 is closed, the electric control limit device 9 of the roller hydraulic pusher 13 is opened, the hydraulic push rod 11 retracts, and the roller pushes forward → repeat the operation to push to the starting support 27.

[0047] In this step, if Figure 2 As shown, an electric control limit device 9 is provided at the center of the reaction support seat steel frame 10 , and limit wing plates 19 are symmetrically provided on both sides. The limit wing plates 19 are provided on both sides of the guide rail 16 .

[0048] like Figure 1 As shown, an electric-controlled limit device 9 is provided at the center of the roller hydraulic pusher 13, and the electric-controlled limit device 9 of the roller hydraulic pusher 13 and the central electric-controlled limit device 9 of the reaction support seat steel frame 10 are both connected to the electric-controlled reaction support 14 through a circuit.

[0049] S5. Assembling the negative ring segments 21: After the shield machine 4 is pushed onto the starting support 27, a reaction frame is set up in the air shaft, and the negative ring segments 21 are manually assembled between the reaction frame and the shield jack. Steel reinforcement pieces 24 are added to the inner wall of the negative ring segments 21 through second connecting bolts 23.

[0050] In this step, if Figure 7 As shown, several steel reinforcement pieces 24 are symmetrically arranged and arranged along the entire length of the inner wall of the negative ring segment 21 , and the bottom of the steel reinforcement piece 24 is connected and fixed to each abutting negative ring segment 21 through a second connecting bolt 23 .

[0051] Among them, after the plurality of negative ring segments 21 are spliced ​​along the circumferential direction, the plurality of negative ring segments 21 are assembled to form the entire segment 8 .

[0052] S6. The shield machine 4 starts and the negative ring segment 21 is reinforced: before the shield starts, an arc-shaped water-stop steel plate is welded on the embedded steel ring 3 of the receiving end retaining wall 2. After the shield machine 4 starts, transverse arc-shaped support plates 22 are symmetrically installed on both sides of the negative ring segment 21 that has escaped from the shield tail. At the same time, the steel wire rope 26 of the prestressed tensioner 28 is used to tighten the outer side of the negative ring segment 21.

[0053] In the steps, Figure 8 、 Figure 9 As shown, the arc-shaped water-stop steel plate includes an upper arc-shaped water-stop steel plate 29 and a lower arc-shaped water-stop steel plate 30 that are symmetrically arranged, and the upper arc-shaped water-stop steel plate 29 and the lower arc-shaped water-stop steel plate 30 are both welded perpendicular to the embedded steel ring 3.

[0054] When the embedded steel ring 3 is set at the enclosure wall 2 , the hinge plate 6 is simultaneously connected to the outer side of the embedded steel ring 3 along the circumferential direction through the first connecting bolt 5 , and the rubber curtain plate 7 is connected to the hinge plate 6 .

[0055] like Figure 7 As shown, an adjustable hydraulic support seat 25 is provided on the side of the transverse arc support plate 22, and the bottom of the adjustable hydraulic support seat 25 abuts against the side retaining wall 2; at least two prestressed tensioners 28 are symmetrically arranged on both sides of the starting support 27, and the steel wire rope 26 is wrapped around the outer periphery of the negative ring segment 21 and the two ends are cross-connected in at least two prestressed tensioners 28.

[0056] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that is the same or similar to that of the present application falls within the scope of protection of the present invention.

Claims

1. A large-diameter shield tunneling system, characterized by: The invention comprises a steel-concrete prefabricated pedestal (12) and a shield machine (4) arranged on the upper part of the steel-concrete prefabricated pedestal (12). The central axis of the steel-concrete prefabricated pedestal (12) is consistent with the central axis of the ventilation shaft. The top surface of the steel-concrete prefabricated pedestal (12) is provided with a central embedded steel support (20) along the central axis. Side embedded steel supports (17) are symmetrically provided along both sides of the central embedded steel support (20). The first section of the steel-concrete prefabricated pedestal (12) is in contact with the enclosure wall (2), and the last section is in contact with the starting support (27).

2. The large-diameter shield tunneling system according to claim 1 is characterized in that: Guide rails (16) are installed on the side pre-buried steel supports (17) and the central pre-buried steel supports (20), and a concrete template is installed on the upper part of the steel-concrete prefabricated pedestal (12) so that the concrete template can be used for the cast-in-place concrete (18) area.

3. The large-diameter shield tunneling system according to claim 2 is characterized in that: The shell of the shield machine (4) is connected with a steel plate and a roller assembly (15); the shield tail is installed with an electric control reaction force support (14); a reaction force support seat type steel frame (10) and a roller hydraulic pusher (13) are installed on the guide rail (16); and a hydraulic push rod (11) is set between the reaction force support seat type steel frame (10) and the electric control reaction force support (14) so ​​that the hydraulic push rod (11) and the roller hydraulic pusher (13) push alternately.

4. The large-diameter shield tunneling system according to claim 1, characterized in that: A reaction frame is set up in the air shaft, and a plurality of negative ring segments (21) are assembled and connected between the reaction frame and the shield jack. The inner wall of the negative ring segment (21) is additionally provided with a steel reinforcement piece (24) through a second connecting bolt (23).

5. The large-diameter shield tunneling system according to claim 4 is characterized in that: The embedded steel ring (3) of the enclosure wall (2) is provided with an arc-shaped water-stopping steel plate, and the negative ring segment (21) is symmetrically installed with transverse arc-shaped support plates (22) on both sides, and the outer side of the negative ring segment (21) is tightened by a steel wire rope (26) of a prestressed tensioner (28).

6. The large-diameter shield tunneling system according to claim 2, characterized in that: The guide rail (16) is connected perpendicularly to the top surfaces of the central embedded steel support (20) and the side embedded steel support (17).

7. The large-diameter shield tunneling system according to claim 3 is characterized in that: An electric control limit device (9) is arranged at the center of the reaction support seat steel frame (10), and limit wing plates (19) are symmetrically arranged on both sides. The limit wing plates (19) are arranged on both sides of the guide rail (16).

8. The large-diameter shield tunneling system according to claim 3 is characterized in that: An electric control limit device (9) is provided at the center of the roller hydraulic pusher (13), and the electric control limit device (9) of the roller hydraulic pusher (13) and the central electric control limit device (9) of the reaction force support seat steel frame (10) are both connected to the electric control reaction force support seat (14) through a circuit.

9. The large-diameter shield tunneling system according to claim 5, characterized in that: The arc-shaped water-stop steel plate comprises an upper arc-shaped water-stop steel plate (29) and a lower arc-shaped water-stop steel plate (30) which are symmetrically arranged, and the upper arc-shaped water-stop steel plate (29) and the lower arc-shaped water-stop steel plate (30) are both perpendicular to the embedded steel ring (3).

10. The large-diameter shield tunneling system according to claim 5, characterized in that: An adjustable hydraulic support seat (25) is provided on the side of the transverse arc support plate (22), and the bottom of the adjustable hydraulic support seat (25) is in contact with the side enclosure wall (2); at least two prestressed tensioners (28) are symmetrically arranged on both sides of the starting bracket (27), and the steel wire rope (26) is wrapped around the outer periphery of the negative ring segment (21) and then the two ends are cross-connected in the at least two prestressed tensioners (28).

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