A rear-mounted segment structure and installation method for a shield tunnel

Abstract

The present invention provides a post-installed segment structure and an installation method for a shield tunnel, which are used to replace damaged segments in the tunnel, including a segment fixed end and a segment sliding end. The segment fixed end and the segment sliding end are provided with a tongue and groove along the annular direction, and a telescopic member is provided in the middle. The two ends of the telescopic member are respectively connected with the embedded member of the segment fixed end and the embedded member in the segment sliding end. The telescopic member pushes the segment sliding end to slide relative to the segment fixed end along the annular tangent direction. The overall size is the same as the size of the replaced segment structure. The post-installed segment is provided with a bent bolt embedded member and a hand hole. The post-installed segment is connected to the surrounding original segments through the bent bolts. The present invention adopts advance prefabrication, shortens the construction period, reduces the possibility of re-damage during the construction process, the segment quality is controllable, the ring ovality of the segment is guaranteed, fewer people, materials and equipment are used, less investment is made in safe production and civilized construction during the construction process, and the overall cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel engineering, and in particular relates to a rear-mounted segment structure of a shield tunnel and an installation method thereof. Background Art

[0002] During the tunnel construction process using the shield method, after the shield segments are assembled by staggered splicing, the segments are interlaced and squeezed with each other to form a unified force system. Theoretically, the assembled shield segments are irreversible. However, as the tunnel progresses from the initial trial run to long-term operation, it will inevitably be affected by external factors such as changes in geological conditions, surrounding construction, and emergencies. When the segments are severely damaged, the degree of damage or cracks exceed the requirements of the design and specifications, affecting safety in use and failing to meet the force requirements of subway operations, the existing technology often uses the method of dismantling the segments and supporting cast-in-place for repair. After the construction is completed, check whether there is leakage at each seam and inject grouting again to stop water. However, the existing technology has the following disadvantages:

[0003] 1. The quality of the segments formed by the cast-in-place structure cannot be guaranteed, the integrity is poor compared with the old prefabricated structure, and the ovality of the ring is difficult to control;

[0004] 2. The construction process is complex, the construction period is long, and the strength of the cast-in-place segment concrete is slow. Before the strength reaches the expected value, external factors may cause damage to the cast-in-place segment concrete, resulting in cracks, deformation, etc., and ultimately fail to achieve the purpose of repair;

[0005] 3. The construction process is complicated, the investment in manpower, materials and machinery is large, and the investment cost for safe production and civilized construction is high. Summary of the invention

[0006] The present invention makes improvements to the problems existing in the above-mentioned prior art, that is, the present invention provides a rear-mounted segment structure for a shield tunnel, which has high segment strength, good integrity with the original adjacent segment structure, simple construction process, short construction period, good repair effect and low cost.

[0007] In order to solve the above technical problems, the present invention provides a post-installed segment structure of a shield tunnel, which is used to replace damaged segments in the tunnel, including a segment fixed end and a first segment sliding end, wherein the segment fixed end and the first segment sliding end are both provided with a tongue and groove along the circumferential direction, and a telescopic member is provided between the segment fixed end and the first segment sliding end, wherein the two ends of the telescopic member are respectively connected to the embedded member of the segment fixed end and the embedded member in the first segment sliding end, and the telescopic member pushes the first segment sliding end to slide relative to the segment fixed end along the circumferential direction, and the overall size of the post-installed segment after installation is completed is the same as the size of the replaced segment structure.

[0008] Preferably, it also includes bent bolt embedded parts, and the number and positions of the bent bolt embedded parts correspond to the bent bolt embedded parts of the surrounding segments of the damaged segment.

[0009] Preferably, the first telescopic member is a thrust bolt or a hydraulic rod.

[0010] Preferably, there are at least two first telescopic members.

[0011] Preferably, the first telescopic members are evenly distributed along the annular tongue and groove direction.

[0012] Preferably, the maximum displacement of the fixed end of the segment and the first segment sliding end in the annular tangential direction is m, and the range of the maximum displacement m is 35 to 75 mm.

[0013] Preferably, a support rod is provided between each adjacent first telescopic member, and the support rod is composed of multiple sections of pipe fittings with different diameters connected together. The length of the support rod is changed by controlling the overlap length of adjacent pipe fittings, and the two ends of the support rod are respectively fixedly connected to the fixed end of the pipe segment and the sliding end of the first pipe segment.

[0014] Preferably, it also includes a length locking device which can lock the overlapping length of adjacent pipes.

[0015] Preferably, it also includes a second pipe segment sliding end, and the pipe segment fixed end and the second pipe segment sliding end are both provided with a tongue and groove along the annular tangential direction, and a second telescopic member is provided between the pipe segment fixed end and the second pipe segment sliding end, and the two ends of the second telescopic member are respectively connected to the embedded parts of the pipe segment fixed end and the embedded parts in the second pipe segment sliding end, and the second telescopic member pushes the second pipe segment sliding end to slide relative to the pipe segment fixed end along the annular direction.

[0016] The present invention also discloses an installation method, which comprises the following steps:

[0017] Reinforce the segments around the damaged segments;

[0018] Remove damaged segments;

[0019] The rear-mounted segment is fixed to the existing segment structure with bent bolts, and the telescopic member is adjusted so that the sliding end of the segment slides outward until it is close to the existing segment structure;

[0020] Pressure grouting and curing between the sliding end and the fixed end of the segment;

[0021] Remove formwork and reinforcement devices.

[0022] Through the above technical solution, the rear-mounted segment structure suitable for replacing the segment is prefabricated in advance, the fixed end and the sliding end of the prefabricated rear-mounted segment are connected through telescopic parts, adjusted to the minimum relative displacement, the segments around the damaged segment are fixed on site, the back of the damaged segment is reinforced by grouting, the segment is removed and replaced, all the telescopic parts are adjusted to the maximum simultaneously, the tongue and groove part is pressure grouting, grouting is performed through the grouting port of the rear-mounted segment, the fixed bracket is removed, and the repair is completed. The entire construction process requires less manpower, materials, and equipment, the construction period is short, the influence of the outside world is small, the integrity with the original adjacent segment structure is good, the segment strength is guaranteed, and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a vertical view of a rear-mounted segment structure of a shield tunnel according to an embodiment of the present invention, in which the relative displacement between the segment sliding end and the segment sliding end is the largest;

[0024] Figure 2 It is a vertical view of a rear-mounted segment structure of a shield tunnel according to an embodiment of the present invention, in which the relative displacement between the segment sliding end and the segment sliding end is minimal;

[0025] Figure 3 yes Figure 1 A partial enlarged view of area B of the embodiment;

[0026] Figure 4 yes Figure 2 AA cross-sectional view of the embodiment;

[0027] Figure 5 yes Figure 2 The schematic diagram of the structure of the embodiment in the R direction;

[0028] Figure 6 yes Figure 1 The schematic diagram of the structure of the embodiment in the R direction;

[0029] Figure 7 It is a structural schematic diagram of a support rod of a rear-mounted segment structure of a shield tunnel according to an embodiment of the invention;

[0030] Figure 8 It is a schematic diagram of a rear-mounted segment structure of a shield tunnel according to another embodiment of the present invention;

[0031] Fig. 9 yes Figure 8 BB cross-sectional view of the embodiment;

[0032] Fig.10 It is a three-dimensional schematic diagram of the installation process of a rear-mounted segment structure of a shield tunnel according to an embodiment of the present invention;

[0033] Fig.11 It is the cross-sectional view and top view of the pre-dismantled damaged segments of the tunnel segment ring;

[0034] Fig.12 It is the cross-sectional view and top view of the tunnel segment ring after the damaged segment is removed;

[0035] Fig.13 It is the cross-sectional view and top view of the pre-installed post-installed segment of the tunnel segment ring;

[0036] Fig.14 It is the cross-section and top view of the in-place segment after the tunnel segment ring is installed;

[0037] In the figure:

[0038] 1. Segment fixed end 2. First segment sliding end 3. Bent bolt

[0039] 4. Push bolt 5. Support rod 6. Grouting hole.

[0040] 7. Sliding end of the second pipe segment 8. Fixed bracket 9. Pipe segment to be removed and replaced

[0041] 10. Post-installed pipe segment 11. Grouting joint DETAILED DESCRIPTION

[0042] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They 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 direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0044] The post-installed segments can be prefabricated in advance. For example, during tunnel construction, a certain number of post-installed segments can be prefabricated according to the segment size used in the tunnel, that is, the post-installed segments used for later replacement of the segments. The production method of the post-installed segments is as follows:

[0045] ① Tie the steel bars at the fixed ends of the segments according to the construction drawings, install the embedded parts of bent bolts, embedded parts of expansion parts, embedded parts of support rods and reserved modules for hand holes, and seal them well. Then install and fix the molds, pour concrete, and maintain the molds;

[0046] ② Tie the steel bars at the sliding end of the pipe segment according to the construction drawings, install the embedded parts of bent bolts, embedded parts of telescopic parts, embedded parts of support rods and reserved modules for hand holes, then install and fix the mold, pour concrete, and maintain the mold;

[0047] ③ The width of the tongue is more suitable to be 35-75mm. The relative displacement between the sliding end and the fixed end of the manufactured segment is 35-75mm, that is, the width of the tongue is more suitable to be 35-75mm, so as to ensure that the rear-mounted segment structure can be installed to the repair position when the tongue of the sliding end and the fixed end of the segment is dense, and the distance between the edge and the installation space is minimized. After the segment structure is adjusted and installed, the overall size is the same as the size of the replaced segment structure;

[0048] ④ Place the segment sliding end and segment fixed end on a special assembly stand, install sealing and waterproof materials at the tongue and groove, install the push bolts and support rods in the bolt slots at the segment fixed end, and use the hand holes to rotate the bolts at the same time to complete the tight connection between the segment sliding end and the segment fixed end;

[0049] ⑤ After taking measures to protect and fix the finished product, complete the production of the rear-mounted pipe segments and store them for future use.

[0050] For example, Figure 1 This is an elevation view of the rear-mounted segment structure of a shield tunnel in an embodiment of the present invention, where the relative displacement between the segment sliding end and the segment sliding end is the largest, including a segment fixed end 1 and a first segment sliding end 2, wherein the upper end of the segment fixed end 1 and the lower end of the first segment sliding end 2 are connected via a tongue-and-groove connection, a sealing strip is arranged in the tongue-and-groove to play a sealing and waterproofing role, and also includes a first telescopic member, and embedded members of the first telescopic member are arranged on the segment fixed end 1 and the first segment sliding end 2, preferably, the first telescopic member can be a jacking bolt 5 or a hydraulic rod. It should be noted that this embodiment does not limit the number and position of the first telescopic member and the corresponding embedded members, for example, preferably two or four are evenly distributed along the tongue-and-groove direction. The first telescopic member pushes the first segment sliding end 2 to slide relative to the segment fixed end 1 along the annular tangent direction. The tongue and groove of the rear-mounted segment structure in the normal state is dense, that is, the relative displacement between the segment fixed end 1 and the first segment sliding end 2 is zero, which is convenient for later replacement and installation. After installation, the size of the rear-mounted segment is the same as the size of the damaged segment structure to be replaced.

[0051] Among them, the post-mounted pipe segment is provided with bent bolt 3 embedded parts, and the number, position and opening direction of the bent bolt 3 embedded parts are compatible with the bent bolt embedded parts of the pipe segments around the original damaged pipe segment.

[0052] Among them, the rear-mounted pipe segment is provided with a grouting hole 6. After the rear-mounted pipe segment is installed and fixed, pressure grouting is performed on the back of the rear-mounted pipe segment through the grouting hole 6 to ensure that there is no gap behind the rear-mounted pipe segment structure, thereby ensuring the integrity and strength of the structure.

[0053] Among them, after the installation and fixation of the post-mounted segment is completed, a template is set up above the tongue and groove, and pressure grouting is performed to cast and connect the fixed end 1 and the sliding end 2 of the segment together to improve the integrity and strength of the structure. The first telescopic member bears the circumferential shear force between the first segment sliding end 2 and the segment fixed end 1 during construction and operation.

[0054] For example, Figure 2 It is a vertical view of a rear-mounted segment structure of a shield tunnel in an embodiment of the present invention, in which the relative displacement between the sliding end and the sliding end of the segment is minimal. The rear-mounted segment is in a normal state, and the tongue and groove between the fixed end 1 of the segment and the first sliding end 2 of the segment are tightly combined, that is, the relative displacement between the fixed end 1 of the segment and the first sliding end 2 of the segment is zero, which is suitable for storage and later installation.

[0055] For example, Figure 3 yes Figure 2 A partial enlarged view of area B of the embodiment, specifically, the embedded part near the bolt head of the push bolt 4 is provided with a thread, and the embedded part near the screw end is provided with a pivot hole, the screw end of the push bolt 4 is installed in the pivot hole, and the push bolt 4 can rotate around the screw axis in the above-mentioned pivot hole.

[0056] For example, Figure 4 yes Figure 2 In the AA cross-sectional view of the embodiment, the rear-mounted segment is connected to the adjacent original segment through the bent bolt 3.

[0057] For example, Figure 5 , Figure 6 This is a schematic diagram of the R-direction structure of an embodiment of the present invention. The fixed end 1 of the segment and the sliding end 2 of the segment are connected by a tongue-and-groove connection. The sliding end of the segment and the fixed end of the segment move relative to each other through the rotation of the push bolt, so that the post-mounted segment fits tightly with the original segment.

[0058] In a preferred embodiment, a support rod 5 is provided between each adjacent telescopic member, and the support rod 5 can be extended or shortened, and the support rod 5 also includes a locking structure to lock the current length. Figure 7 As shown, the support rod includes multiple sections of pipes with different diameters that can be sleeved together. The pipes are sleeved together in sequence, and a retaining spring is arranged inside to limit the position where each section of the pipe extends. In a further preferred embodiment, the outer wall of the pipe is provided with anti-slip grooves, and the auxiliary telescopic parts bear the annular tangential shear force, thereby increasing the integrity and strength of the structure.

[0059] A preferred solution is Figure 8 As shown, it also includes a second segment sliding end 7, the segment fixed end 1 and the second segment sliding end 7 are both provided with a tongue and groove along the annular tangential direction, a second telescopic member is provided between the segment fixed end 1 and the second segment sliding end 7, and the two ends of the second telescopic member are respectively connected to the embedded parts of the segment fixed end 1 and the embedded parts of the second segment sliding end 7, and the second telescopic member pushes the second segment sliding end 7 to slide relative to the segment fixed end 1 along the annular direction.

[0060] For example, Fig. 9 yes Figure 8 BB cross-sectional view of the embodiment.

[0061] For example, Figures 10 to 14 As shown, the present invention also discloses an installation method, the steps are:

[0062] Reinforce the pipe segments around the damaged pipe segment 9 to be removed and replaced;

[0063] Remove the damaged pipe segment to be removed and replaced 9;

[0064] The post-installed segment 10 is fixed to the existing segment structure by using bent bolts 3, and the telescopic member is adjusted so that the sliding end of the segment slides outward until it is close to the existing segment structure;

[0065] Pressure grouting and curing between the sliding end and the fixed end of the segment;

[0066] Remove formwork and reinforcement devices.

[0067] Among them, during the adjustment process of the telescopic parts, the preferred scheme is synchronous adjustment, such as synchronously adjusting all the first telescopic parts at the same time to ensure that the rear-mounted segment moves smoothly in the annular tangential direction, so that the sliding end 2 of the first segment slides outward until it is close to the existing segment structure, and synchronously adjusting all the second telescopic parts at the same time to ensure that the rear-mounted segment moves smoothly in the annular direction, so that the sliding end 7 of the second segment slides outward until it is close to the existing segment structure.

[0068] Among them, use the prefabricated post-installed segments, check the tightness of the joints, whether the ring surfaces are consistent, there is no misalignment, the bolt holes and lifting holes are accurately located, and the strength and various indicators meet the requirements; if the size is not suitable, it can be prefabricated on site according to the actual required size

[0069] Among them, before using the post-mounted pipe segments, the tightness of the joint tongue and groove should be checked, whether the ring surfaces are consistent, there should be no misalignment, the bolt holes and lifting holes should be accurately positioned, and the strength and various indicators should meet the requirements.

[0070] Before removing the damaged segments, grouting is performed on the pre-removed segments and adjacent segments to fill the gaps behind the segments and reinforce the surrounding soil. After the grouting is completed, drilling and sampling are performed to check the grouting conditions. Grouting is stopped when there is no obvious water leakage. When conditions permit, three-dimensional finite element software should be used to simulate the installation in advance, and key control should be performed on dangerous processes and stages.

[0071] Among them, fixed brackets are used to support and reinforce the adjacent segments of the pre-removed segments to ensure the structural stability of the subway tunnel during the segment removal and installation process.

[0072] Among them, to remove the damaged pipe segments, a cutting machine can be used to cut the pipe segments into small pieces, and each small piece can be removed step by step. After the removal is completed, the rings and longitudinal seams of the adjacent pipe segments should be cleaned in time, and the elastic rubber pads, water retaining strips and positioning rods should be replaced according to the situation.

[0073] Among them, a mobile segment installation machine can be used for transportation and installation, and the segment can be lifted to the predetermined position. Preferably, the four jacking bolts are adjusted synchronously to make the sliding end of the segment slide smoothly outward until it is close to the existing segment structure, and the position, elevation, flatness and ovality of the annular surface of the rear-mounted segment can be remeasured again to meet the requirements.

[0074] Among them, after the pressure grouting concrete between the sliding end and the fixed end of the segment reaches the predetermined strength, grouting is performed again through the grouting hole in the middle of the segment to ensure that there is no gap behind the rear-mounted segment structure.

[0075] Among them, it is possible to choose to install a deformation monitoring device after the structure is fixed to monitor the deformation of the post-mounted segment structure.

[0076] Among them, when removing the fixed supports, some of the fixed supports can be removed first, and the deformation of the original pipe segments and the post-installed pipe segments can be observed. After the deformation meets the requirements, the remaining supports can be removed.

[0077] Through the above-mentioned technical means and methods, compared with the commonly used technology of cast-in-place segment construction at this stage, the use of prefabrication technology shortens the construction period, reduces the possibility of re-damage during the repair process, can effectively control the quality of the replacement segments, can ensure the ring ovality and project quality of the tunnel segments, uses fewer people, materials and equipment, has low cost, and requires less investment in safe production and civilized construction during the construction process, effectively reducing construction costs.

[0078] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A rear-mounted segment structure of a shield tunnel, used to replace damaged segments of the tunnel, characterized in that: It includes a pipe segment fixed end and a first pipe segment sliding end, and the pipe segment fixed end and the first pipe segment sliding end are both provided with a tongue and groove along the annular direction. A first telescopic member is provided between the pipe segment fixed end and the first pipe segment sliding end, and the two ends of the first telescopic member are respectively connected to the embedded parts of the pipe segment fixed end and the embedded parts of the first pipe segment sliding end. The first telescopic member pushes the first pipe segment sliding end to slide relative to the pipe segment fixed end along the annular tangent direction. After the installation of the post-mounted pipe segment is completed, the overall size is the same as the structural size of the replaced pipe segment.

2. The rear-mounted segment structure of a shield tunnel according to claim 1, characterized in that: It also includes bent bolt embedded parts, the number and positions of the bent bolt embedded parts correspond to the bent bolt embedded parts of the pipe segments surrounding the damaged pipe segment.

3. The rear-mounted segment structure of a shield tunnel according to claim 2, characterized in that: The first telescopic member is a thrust bolt or a hydraulic rod.

4. The rear-mounted segment structure of a shield tunnel according to claim 3, characterized in that: The number of the first telescopic members is at least two.

5. The rear-mounted segment structure of a shield tunnel according to claim 4, characterized in that: The first telescopic members are evenly distributed along the annular tongue and groove direction.

6. The rear-mounted segment structure of a shield tunnel according to claim 5, characterized in that: The maximum displacement of the fixed end of the segment and the first sliding end of the segment in the annular tangential direction is m, and the range of the maximum displacement m is 35 to 75 mm.

7. The rear-mounted segment structure of a shield tunnel according to claim 6, characterized in that: A support rod is provided between each adjacent first telescopic member. The support rod is composed of multiple sections of pipe fittings with different diameters connected together. The length of the support rod is changed by controlling the overlap length of adjacent pipe fittings. The pipe fittings at both ends of the support rod are fixedly connected to the fixed end of the pipe segment and the sliding end of the first pipe segment respectively.

8. The rear-mounted segment structure of a shield tunnel according to claim 7, characterized in that: It also includes a length locking device which can lock the overlapping length of adjacent pipes.

9. A rear-mounted segment structure for a shield tunnel according to any one of claims 1 to 8, characterized in that: It also includes a second pipe segment sliding end, and the pipe segment fixed end and the second pipe segment sliding end are both provided with a tongue and groove along the annular tangential direction. A second telescopic member is provided between the pipe segment fixed end and the second pipe segment sliding end, and the two ends of the second telescopic member are respectively connected to the embedded parts of the pipe segment fixed end and the embedded parts in the first pipe segment sliding end, and the second telescopic member pushes the second pipe segment sliding end to slide relative to the pipe segment fixed end along the annular direction.

10. A method for installing a rear-mounted segment structure of a shield tunnel using any one of claims 1 to 9, characterized in that: The steps are: Reinforce the segments around the damaged segments to be removed and replaced; Remove the damaged segments to be removed and replaced; The rear-mounted segment is fixed to the existing segment structure with bent bolts, and the telescopic member is adjusted so that the sliding end of the segment slides outward until it is close to the existing segment structure; Pressure grouting and curing between the sliding end and the fixed end of the segment; Remove formwork and reinforcement devices.

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