A segment block for high water pressure environment, a tunnel and a construction method thereof

Abstract

The application relates to the technical field of tunnel engineering, and particularly discloses a pipe piece block for a high-water-pressure environment, which is internally provided with a ring-shaped drainage pipe and a grouting hole, the grouting hole is located at the center position of the pipe piece block, the ring-shaped drainage pipe is in communication with the grouting hole, a grouting sleeve is arranged in the grouting hole, the grouting sleeve comprises a grouting hole threaded sleeve inner side section and a grouting hole threaded sleeve outer side section, a grouting hole plugging is arranged in the grouting hole threaded sleeve inner side section, and a radial drainage pipe is arranged in the grouting hole threaded sleeve outer side section. The application further discloses a tunnel for a high-water-pressure environment and a construction method thereof. The drainage pressure relief pipe piece block effectively improves the stress of the pipe piece block, and significantly improves the safety of the tunnel.

Description

Technical Field

[0001] This invention relates to the field of tunnel engineering technology, specifically to a segment block, a tunnel, and a construction method thereof for use in high water pressure environments. Background Technology

[0002] 1. Description of the existing technology

[0003] With the construction of intercity subways, subway lines will encounter sections that traverse mountains. The tunnel segments in these mountain sections will be subjected to extremely high water pressure, and conventional segment structures cannot withstand such high external water pressure. Existing technologies employ measures such as increasing segment thickness and enhancing segment reinforcement to address the adverse effects of high water pressure on the segment structure. Another technical solution involves suspending drainage pipes inside the tunnel or creating openings at the tunnel arch to drain external water into the tunnel, thereby reducing the water pressure outside the tunnel.

[0004] 2. Limitations and shortcomings of existing technologies and the reasons for these shortcomings.

[0005] (1) The technical measures of increasing the thickness of the pipe segments and improving the reinforcement of the pipe segments are adopted to deal with the adverse effects of high water pressure on the stress of the pipe segments. This solution improves the bearing capacity of the pipe segments, but also causes a sharp increase in engineering costs.

[0006] (2) Technical solutions to drain water from outside the tunnel into the tunnel by suspending drainage pipes inside the tunnel or by opening holes at the tunnel arch foot: The former is due to the limited space inside the tunnel, and suspending drainage pipes will occupy valuable underground space. If the tunnel clearance requirements are met, the tunnel diameter needs to be increased, which will inevitably lead to a significant increase in project cost; The latter only opens holes at the tunnel arch foot for drainage. The seepage field formed on the outer wall of the tunnel has high pressure at the tunnel arch top and low pressure at the arch foot. The reduction of external water pressure is uneven, and the stress on the tunnel segments has not been well improved. Summary of the Invention

[0007] To address the aforementioned problems with shield tunnel segments, this invention designs a segment block, a tunnel, and a construction method for use in high water pressure environments, effectively improving the stress on the segments. The specific technical solution is as follows:

[0008] This invention discloses a pipe segment for use in high water pressure environments. The pipe segment has a circumferential drainage pipe and a grouting hole inside. The grouting hole is located at the center of the pipe segment and is connected to the grouting hole. A grouting sleeve is provided inside the grouting hole. The grouting sleeve includes an inner section and an outer section. A grouting hole plug is provided in the inner section of the grouting hole threaded sleeve, and a radial drainage pipe is provided in the outer section of the grouting hole threaded sleeve.

[0009] Furthermore, the radial drainage pipe includes a radial drainage pipe fixing section, a radial drainage pipe water-stopping section, and a radial drainage pipe filter screen. The radial drainage pipe fixing section is threadedly fixed to the outer section of the threaded sleeve of the grouting hole. The radial drainage pipe water-stopping section is provided with a radial drainage pipe water-stopping rubber ring, which is embedded in the radial drainage pipe water-stopping rubber ring groove of the outer section of the threaded sleeve of the grouting hole. A radial drainage pipe filter screen is provided at one end of the radial drainage pipe near the outer arc surface of the pipe segment.

[0010] Furthermore, the grouting hole sealing includes a grouting hole cap, a grouting hole sealing fixing section, and a grouting hole sealing water-stopping section. The grouting hole cap is provided at one end of the grouting hole sealing near the inner arc surface of the segment. The grouting hole sealing fixing section is threadedly fixed to the inner section of the grouting hole threaded sleeve. The grouting hole sealing water-stopping section is provided with a grouting hole sealing water-stopping rubber ring, which is embedded in the grouting hole sealing water-stopping rubber ring groove of the inner section of the grouting hole threaded sleeve.

[0011] Furthermore, a check valve fixing component is provided on the outer section of the threaded sleeve of the grouting hole.

[0012] Furthermore, the two ends of the circumferential drain pipe are provided with end face drain horn grooves.

[0013] Furthermore, the grouting hole is divided into an inner section of the threaded sleeve and an outer section of the threaded sleeve based on the circumferential drainage pipe.

[0014] Furthermore, the center of the circumferential drainage pipe is connected to the grouting hole.

[0015] Furthermore, the ratio of the diameter d of the circumferential drainage pipe to the thickness t of the pipe segment ranges from 8% to 15%.

[0016] The present invention also discloses a drainage and pressure relief tunnel, comprising a capping block, a first adjacent block, a second adjacent block, and several standard blocks. A circumferential drainage pipe is provided inside each of the capping block, the first adjacent block, the second adjacent block, and the standard blocks. A grouting hole is provided radially at the center of each of the capping block, the first adjacent block, the second adjacent block, and the standard blocks. The circumferential drainage pipe communicates with the grouting hole. A track bed is provided at the bottom inner side of the drainage and pressure relief tunnel. A track bed drainage ditch is symmetrically provided at the top of the track bed. The track bed drainage ditch communicates with the circumferential drainage pipe through a drainage hole.

[0017] This invention also discloses a construction method for a drainage and pressure relief tunnel, comprising the following steps:

[0018] S1. During the prefabrication of the tunnel segments, grouting holes and circumferential drainage pipes are pre-embedded. The circumferential drainage pipes are connected to the grouting holes. After the tunnel segments are prefabricated, the position of the circumferential drainage pipes is marked on the inner arc surface of the tunnel segments.

[0019] S2. During the on-site segment assembly construction, grouting is carried out synchronously through the grouting holes pre-embedded in the segments; after the track bed is poured, drainage holes are drilled through the circumferential drainage pipe positions marked on the inner arc surface of the segments to connect the circumferential drainage pipes with the track bed drainage ditches.

[0020] S3. Unscrew the grouting hole cap, open the outer end face of the grouting hole and the concrete segment near the outer arc surface of the segment to form an opening in the outer wall of the segment, install the check valve and the radial drainage pipe water-stop rubber ring, and perform secondary grouting on the outer wall of the segment to form a synchronous grouting layer.

[0021] S4. After the secondary grouting is completed and the grout has solidified, a micro rotary drill gun is used to cut the check valve and the solidified grout outside the check valve to form a groundwater seepage channel. The seepage channel connects the grouting hole and the stratum.

[0022] S5. When installing the radial drainage pipe, fix the radial drainage pipe with the threaded section of the radial drainage pipe fixing section, seal the outer section of the radial drainage pipe and the threaded sleeve of the grouting hole with the water-stop section of the radial drainage pipe, and install the radial drainage pipe filter screen at the end of the radial drainage pipe near the outer arc surface of the pipe segment.

[0023] S6. After installing the radial drainage pipe, promptly seal the inner section of the threaded sleeve of the grouting hole to form a grouting hole seal, so that the entire ring segment forms a system of drainage on the outside and middle parts of the segment and water blocking on the inner wall of the segment.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] (1) The present invention adopts the technical solution of internal drainage and pressure relief of the tunnel segment, which connects the grouting hole of the tunnel segment with the circumferential drainage pipe, which can not only meet the grouting requirements during the tunnel segment construction stage, but also provide the tunnel segment drainage and pressure relief needs during tunnel operation.

[0026] (2) The grouting hole is designed in sections. The outer section is equipped with a check valve and a water-stop ring, which provides the function of preventing grout from flowing into the drainage pipe during grouting and the function of groundwater barrier during operation. The inner section of the grouting hole provides the sealing and plugging conditions of the grouting hole during operation.

[0027] (3) The circumferential drainage pipe is set inside the tunnel segment structure, which avoids the disadvantage of being suspended in the tunnel and occupying valuable underground space; by utilizing the location of the grouting hole of the tunnel segment, the weakening of the circumferential structure of the tunnel segment caused by the addition of new holes in the tunnel segment is avoided, thus ensuring the structural safety of the tunnel segment; the circumferential drainage pipe is connected to the drainage ditch of the tunnel bed through the drainage hole of the track bed, thus realizing the purpose of groundwater flowing from the outside of the tunnel into the drainage system inside the tunnel.

[0028] (4) The circumferential drainage pipe at the longitudinal joint section of the segment is equipped with a bell mouth section, which can ensure the smooth circumferential drainage of the segment even when the segment is assembled in a staggered condition; a radial drainage pipe is set in each segment block of the whole ring, which can achieve relatively uniform drainage and pressure relief around the tunnel, thereby reducing the external water pressure of the segment. Attached Figure Description

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0030] Figure 1 This refers to the pre-embedding of grouting holes and drainage pipes in the overall structure of this invention.

[0031] Figure 2 Construction of the drainage holes in the overall structure of this invention.

[0032] Figure 3 This is for opening the grouting holes and sealing the inner section of the spiral sleeve of the grouting holes in the overall structure of the present invention.

[0033] Figure 4 This refers to the pre-embedding of grouting holes and drainage pipes in a partial structure of the present invention.

[0034] Figure 5 This is for opening the grouting hole and sealing the inner section of the spiral sleeve of the grouting hole in the local structure of the present invention.

[0035] Figure 6 This describes the installation of the radial drainage pipe in a partial structure of the present invention.

[0036] Figure 7 This is for sealing the inner section of the spiral sleeve of the grouting hole in a partial structure of the present invention.

[0037] Figure 8 This refers to the location of the drainage pipe interface on the longitudinal seam end face of the pipe segment under normal operating conditions of this invention.

[0038] Figure 9 This refers to the location of the drainage pipe interface on the longitudinal seam end face of the segment under the misaligned working condition of the present invention.

[0039] In the diagram: 1. Grouting hole; 2. Circumferential drainage pipe; 3. Track bed; 4. Track bed drainage ditch; 5. Drainage hole; 6. Grouting sleeve; 7. Inner section of threaded sleeve for grouting hole; 8. Outer section of threaded sleeve for grouting hole; 9. Check valve fixing component; 10. Radial drainage pipe; 11. Fixed section of radial drainage pipe; 12. Water-stopping section of radial drainage pipe; 13. Filter screen for radial drainage pipe; 14. Water-stopping rubber ring for radial drainage pipe; 15. Groove of water-stopping rubber ring for radial drainage pipe; 16. Outer arc surface of the segment; 17. Capping block; 18. First adjacent section 19. Second adjacent block; 20. Grouting hole plug; 21. Grouting hole cover; 22. Grouting hole plug fixing section; 23. Grouting hole plug water-stopping section; 24. Inner arc surface of the segment; 25. Grouting hole plug water-stopping rubber ring; 26. Grouting hole plug water-stopping rubber ring groove; 27. First standard block; 28. Second standard block; 29. ​​Third standard block; 30. Fourth standard block; 31. Segment outer wall opening; 32. Check valve; 33. Synchronous grouting layer; 34. End face drainage funnel groove; 35. Outer end face of grouting hole. Detailed Implementation

[0040] The present invention will be further described below through specific embodiments, but this is not a limitation of the present invention. Those skilled in the art can make various modifications or improvements based on the basic idea of ​​the present invention, but as long as they do not depart from the basic idea of ​​the present invention, they are all within the protection scope of the present invention.

[0041] One embodiment provided by the present invention is as follows:

[0042] See Figures 1 to 3 This invention discloses a pipe segment for use in high water pressure environments. The pipe segment has a circumferential drainage pipe 2 and a grouting hole 1 inside. The grouting hole 1 is located at the center of the pipe segment. The center of the circumferential drainage pipe 2 is connected to the grouting hole 1. A grouting sleeve 6 is provided inside the grouting hole 1. The grouting hole 1 is divided into an inner section 7 and an outer section 8 of the threaded sleeve based on the circumferential drainage pipe 2. A grouting hole plug 20 is provided in the inner section 7 of the threaded sleeve, and a radial drainage pipe 10 is provided in the outer section 8 of the threaded sleeve, providing fixing conditions for fixing the radial drainage pipe 10 and the subsequent grouting hole plug 20.

[0043] See Figures 4 to 7The radial drainage pipe 10 includes a radial drainage pipe fixing section 11, a radial drainage pipe water-stopping section 12, and a radial drainage pipe filter screen 13. The radial drainage pipe fixing section 11 is threadedly fixed to the outer section 8 of the threaded sleeve of the grouting hole. The radial drainage pipe water-stopping section 12 is provided with a radial drainage pipe water-stopping rubber ring 14, which prevents the secondary grouting slurry and groundwater from flowing into the drainage pipe. The radial drainage pipe water-stopping rubber ring 14 is embedded and fixed in the radial drainage pipe water-stopping rubber ring groove 15 of the outer section 8 of the threaded sleeve of the grouting hole. A radial drainage pipe filter screen 14 is provided at one end of the radial drainage pipe 10 near the outer arc surface of the pipe segment to filter underground sand particles and allow only groundwater to flow in. A check valve fixing component 9 is provided on the outer section 8 of the threaded sleeve of the grouting hole.

[0044] The grouting hole sealing 20 includes a grouting hole cover 21, a grouting hole sealing fixing section 22, and a grouting hole sealing water-stopping section 23. The grouting hole cover 21 is provided at one end of the grouting hole sealing 20 near the inner arc surface 24 of the segment to prevent concrete from flowing into the grouting hole 1 when the precast concrete of the segment is used. The grouting hole sealing fixing section 22 is threadedly fixed to the inner side section 7 of the grouting hole threaded sleeve. The grouting hole sealing water-stopping section 23 is provided with a grouting hole sealing water-stopping rubber ring 25 to prevent groundwater in the drainage pipe from seeping into the inner side of the segment. The grouting hole sealing water-stopping rubber ring 25 is embedded and fixed in the grouting hole sealing water-stopping rubber ring groove 26 of the inner side section 7 of the grouting hole threaded sleeve, which plays a role in water blocking and sealing. Grouting hole 1 is designed in sections. The outer section is equipped with a check valve 32 and a water-stop ring, which provides the function of preventing grout from flowing into the drainage pipe during grouting and the function of groundwater barrier during operation. The inner section of grouting hole 1 provides sealing and plugging conditions for grouting hole 1 during operation.

[0045] See Figure 8 The two ends of the circumferential drainage pipe 2 are provided with end face drainage funnel grooves 34, that is, the drainage pipes of each segment near the end face of the longitudinal joint are designed in the shape of funnel mouth, which can ensure the smooth circumferential drainage of the segment even when the segments are assembled in a misaligned condition; each segment of the whole ring is provided with a radial drainage pipe 10, which can achieve relatively uniform drainage and pressure relief around the tunnel, thereby reducing the external water pressure of the segment.

[0046] Furthermore, if the diameter d of the circumferential drainage pipe 2 is too large, it will weaken the thickness of the pipe segment at the circumferential drainage pipe 2 to some extent, reducing the load-bearing capacity of the segment; if the diameter d of the circumferential drainage pipe 2 is too small, the water passage cross-section of the circumferential drainage pipe 2 will be too small, which will not meet the drainage capacity requirements of the segment when the groundwater volume is abundant. Therefore, considering the overall load-bearing capacity and drainage pressure relief capacity of the segment, the design value range for the ratio of the diameter d of the circumferential drainage pipe 2 to the thickness t of the segment is d / t = 8%~15%. For example, for a segment with a thickness of 400mm, a circumferential drainage pipe 2 with a diameter of 32mm~60mm is configured.

[0047] In addition, the pre-embedded circumferential drainage pipe 2 inside the segment, although reducing the segment thickness locally, significantly reduces the external water pressure due to the drainage and pressure relief function, resulting in a smaller required segment thickness in the design calculation. Furthermore, as can be seen from the stress mechanism of the segment, the segment is mainly subjected to circumferential load, and the main reinforcing bars are also arranged in rings along the longitudinal direction of the tunnel (the longitudinal spacing of each ring of reinforcing bars is usually ≥100mm, which is greater than the diameter d of the circumferential drainage pipe 2). Therefore, the pre-embedding of the circumferential drainage pipe 2 in a local section will not interfere with the arrangement of the circumferential reinforcing bars, and thus has a limited impact on weakening the circumferential bearing capacity of the segment.

[0048] This invention also discloses a drainage and pressure relief tunnel, comprising a capping block 17, a first adjacent block 18, a second adjacent block 19, and several standard blocks. A circumferential drainage pipe 2 is disposed inside each of the capping block 17, the first adjacent block 18, the second adjacent block 19, and the standard blocks. A grouting hole 1 is radially disposed at the center of each of the capping block 17, the first adjacent block 18, the second adjacent block 19, and the standard blocks. The circumferential drainage pipe 2 communicates with the grouting hole 1. A track bed 3 is disposed at the bottom inner side of the drainage and pressure relief tunnel. A track bed drainage ditch 4 is symmetrically disposed at the top of the track bed 3. The track bed drainage ditch 4 communicates with the circumferential drainage pipe 2 through a drainage hole 5. In a preferred embodiment of this invention, four standard blocks are designated: a first standard block 27, a second standard block 28, a third standard block 29, and a fourth standard block 30. The drainage holes 5 are respectively connected to the circumferential drainage pipes 2 in the second adjacent block 19 and the fourth standard block 30.

[0049] This invention patent adopts a technical solution of internal drainage and pressure relief for tunnel segments, connecting the grouting holes 1 of the tunnel segments with the circumferential drainage pipe 2. This not only meets the grouting requirements during the tunnel segment construction stage but also provides drainage and pressure relief for the tunnel segments during tunnel operation. At the same time, the circumferential drainage pipe 2 is set inside the tunnel segment structure, avoiding the disadvantage of being suspended inside the tunnel and occupying valuable underground space. By utilizing the location of the grouting holes 1, the weakening of the circumferential structure of the tunnel segments caused by the addition of new openings is avoided, ensuring the structural safety of the tunnel segments. The circumferential drainage pipe 2 connects to the drainage ditch 4 of the track bed 3 through the drainage hole 5, realizing the purpose of groundwater flowing from the outside of the tunnel into the tunnel's internal drainage system.

[0050] This invention also discloses a construction method for a drainage and pressure relief tunnel, comprising the following steps:

[0051] S1. During the prefabrication of the tunnel segments, grouting holes 1 and circumferential drainage pipes 2 are pre-embedded. The circumferential drainage pipes 2 are connected to the grouting holes 1. After the tunnel segments are prefabricated, the position of the circumferential drainage pipes 2 is marked on the inner arc surface 24 of the tunnel segments.

[0052] S2. During the on-site segment assembly construction, grouting is carried out synchronously through the grouting holes 1 pre-embedded in the segments; after the track bed 3 is poured, drainage holes 5 are drilled through the circumferential drainage pipe 2 marked on the inner arc surface 24 of the segments to connect the circumferential drainage pipe 2 with the track bed drainage ditch 4.

[0053] S3. Unscrew the grouting hole cap 21, open the outer end face of the grouting hole 1 and the concrete segment near the outer arc surface of the segment to form an opening on the outer wall of the segment. The outer section 8 of the threaded sleeve of the grouting hole is equipped with a check valve fixing part 9. Install the check valve 32 and the radial drainage pipe water-stop rubber ring 14, and perform secondary grouting on the outer wall of the segment to form a synchronous grouting layer 33. The check valve 32 is used to prevent grout from flowing into the grouting hole 1 and the drainage pipe during the secondary grouting of the segment.

[0054] S4. After the secondary grouting is completed and the grout has solidified, a micro rotary drill gun is used to cut the check valve 32 and the solidified grout outside the check valve 32 to form a groundwater seepage channel. The seepage channel connects the grouting hole 1 with the stratum.

[0055] S5. When installing the radial drainage pipe 10, the radial drainage pipe 10 is threadedly fixed by the radial drainage pipe fixing section 11, and the radial drainage pipe 10 is sealed to the outer section 8 of the threaded sleeve of the grouting hole by the radial drainage pipe water-stopping section 12. The radial drainage pipe filter screen 13 is installed at the end of the radial drainage pipe 10 near the outer arc surface of the pipe segment.

[0056] S6. After installing the radial drainage pipe 10, promptly seal the inner section 7 of the threaded sleeve of the grouting hole to form the grouting hole seal 20, so that the entire ring segment forms a system of drainage on the outside and middle parts of the segment and water blocking on the inner wall of the segment.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A segment block for use in high water pressure environments, characterized in that, The tube segment is provided with a circumferential drainage pipe (2) and a grouting hole (1) inside. The grouting hole (1) is located at the center of the tube segment. The circumferential drainage pipe (2) is connected to the grouting hole (1). A grouting sleeve (6) is provided inside the grouting hole (1). The grouting sleeve (6) includes an inner section (7) of the grouting hole threaded sleeve and an outer section (8) of the grouting hole threaded sleeve. A grouting hole plug (20) is provided inside the inner section (7) of the grouting hole threaded sleeve, and a radial drainage pipe (10) is provided inside the outer section (8) of the grouting hole threaded sleeve.

2. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The radial drainage pipe (10) includes a radial drainage pipe fixing section (11), a radial drainage pipe water-stopping section (12), and a radial drainage pipe filter screen (13). The radial drainage pipe fixing section (11) is threadedly fixed to the outer section (8) of the threaded sleeve of the grouting hole. The radial drainage pipe water-stopping section (12) is provided with a radial drainage pipe water-stopping rubber ring (14). The radial drainage pipe water-stopping rubber ring (14) is embedded and fixed in the radial drainage pipe water-stopping rubber ring groove (15) of the outer section (8) of the threaded sleeve of the grouting hole. The radial drainage pipe (10) is provided with a radial drainage pipe filter screen (13) at one end near the outer arc surface (16) of the pipe segment.

3. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The grouting hole plug (20) includes a grouting hole cover (21), a grouting hole plug fixing section (22), and a grouting hole plug water-stopping section (23). The grouting hole plug (20) is provided with a grouting hole cover (21) at one end near the inner arc surface (24) of the segment. The grouting hole plug fixing section (22) is threadedly fixed to the inner side section (7) of the grouting hole threaded sleeve. The grouting hole plug water-stopping section (23) is provided with a grouting hole plug water-stopping rubber ring (25). The grouting hole plug water-stopping rubber ring (25) is embedded and fixed in the grouting hole plug water-stopping rubber ring groove (26) of the inner side section (7) of the grouting hole threaded sleeve.

4. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The outer section (8) of the threaded sleeve of the grouting hole is provided with a check valve fixing component (9).

5. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The two ends of the circumferential drain pipe (2) are provided with end face drain horn grooves (34).

6. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The grouting hole (1) is divided into an inner section (7) of the grouting hole threaded sleeve and an outer section (8) of the grouting hole threaded sleeve based on the circumferential drainage pipe (2).

7. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The center of the circumferential drainage pipe (2) is connected to the grouting hole (1).

8. The pipe segment block for high water pressure environment according to claim 1, characterized in that, The ratio of the diameter d of the circumferential drainage pipe (2) to the thickness t of the pipe segment ranges from 8% to 15%.

9. A drainage and pressure relief tunnel, characterized in that, The drainage and pressure relief tunnel is composed of several segments of pipe for high water pressure environment as described in any one of claims 1-8, spliced ​​together in a circumferential manner; The bottom of the inner side of the drainage and pressure relief tunnel is provided with a track bed (3), and the top of the track bed (3) is symmetrically provided with track bed drainage ditches (4). The track bed drainage ditches (4) are connected to the circumferential drainage pipe (2) through the drainage hole (5).

10. A construction method for tunnels in high water pressure environments, characterized in that, Includes the following steps: S1. When prefabricating the segments, grouting holes (1) and circumferential drainage pipes (2) are pre-embedded. The circumferential drainage pipes (2) are connected to the grouting holes (1). After the segments are prefabricated, the position of the circumferential drainage pipes (2) is marked on the inner arc surface of the segments. S2. During the on-site segment assembly construction, grouting is carried out synchronously through the grouting holes (1) pre-embedded in the segments; after the track bed (3) is poured, drainage holes (5) are drilled through the circumferential drainage pipe (2) marked on the inner arc surface of the segments to connect the circumferential drainage pipe (2) with the track bed drainage ditch (4); S3. Unscrew the grouting hole cap (21), open the concrete pipe segment with the outer end face (35) of the grouting hole and the outer arc surface (16) of the pipe segment to form an opening (31) on the outer wall of the pipe segment, install a check valve (32) and a radial drainage pipe water-stop rubber ring (14), and perform secondary grouting on the outer wall of the pipe segment to form a synchronous grouting layer (33). S4. After the secondary grouting is completed and the grout solidifies, a micro rotary drill gun is used to cut the check valve (32) and the solidified grout outside the check valve (32) to form a groundwater seepage channel. The seepage channel connects the grouting hole (1) with the stratum. S5. When installing the radial drain pipe (10), the radial drain pipe (10) is fixed by the radial drain pipe fixing section (11) thread, and the radial drain pipe (10) is sealed with the outer section (8) of the threaded sleeve of the grouting hole by the radial drain pipe water-stop section (12). The radial drain pipe filter screen (13) is installed at the end of the radial drain pipe (10) near the outer arc surface (16) of the pipe segment. S6. After installing the radial drainage pipe (10), promptly seal the inner section (7) of the threaded sleeve of the grouting hole to form a grouting hole seal (20), so that the entire ring of pipe segments forms a system of drainage on the outside and middle parts of the pipe segments and water blocking on the inner wall of the pipe segments.

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