A construction method for preventing pipe segments from floating up in water-rich rock formations

Abstract

The present invention provides a construction method for preventing pipe segments from floating up that is suitable for water-rich rock formations. In this method, threaded sleeves are buried in the reserved grouting holes of the pipe segments. After the formed pipe segments are removed from the shield tail, screw rods are respectively inserted into the threaded sleeves. The screw rods and the threaded sleeves of the pipe segment embedded parts form a matching device, which can judge the grouting effect and facilitate secondary grouting behind the pipe segment wall. The present invention simplifies the operation process of the construction site, is simple and easy to operate, has high reliability, effectively solves the problem of groundwater scouring in hard rock formations, and can improve the forming quality of shield tunnel pipe segments in hard rock formations.

Description

Technical Field

[0001] The invention relates to the technical field of shield tunnel construction, and in particular to a construction method suitable for preventing pipe segments from floating up in water-rich rock formations. Background Art

[0002] In recent years, the shield method has become one of the main construction methods adopted for tunnel construction in the southeastern coastal areas of my country. This method adopts the mode of excavation and support to achieve mechanized construction, which has the advantages of high efficiency, low cost, and low environmental impact. During the shield construction process, the cutter head excavation diameter is usually larger than the outer diameter of the segment. Due to the incomplete synchronous grouting and the shrinkage of the slurry volume, the installed segment will form a gap with the surrounding strata after it is removed from the shield tail. Therefore, it is necessary to perform secondary grouting through the grouting holes reserved on the segment to fill the gap, reduce the problems of misalignment and local water leakage caused by the floating of the segment, and thus improve the quality of the formed segment.

[0003] During the construction process in water-rich hard rock formations, the synchronous grouting slurry is diluted by groundwater, resulting in a prolonged initial setting time of the slurry, and the segments are wrapped by external groundwater or unsolidified slurry, which can easily aggravate the problem of segment floating. In the article "Research on Segment Floating Control Technology of Full-section Hard Rock Formation Shield Tunnels" published in the journal "Tunnel Construction", Yang Yandong et al. pointed out that the maximum floating amount of the segments in the right line 259-264 ring of a shield section of Guangzhou Metro Line 7 reached 118mm after 15 days of excavation, resulting in continuous water leakage in this section of the tunnel, seriously affecting the quality of the formed tunnel.

[0004] At present, in the relevant technologies to solve the floating of shield tunnel segments, the dewatering method is widely used, that is, the water pressure outside the segments is reduced by pumping or constructing dewatering wells in the tunnel, thereby reducing the buoyancy of the segments. However, this method may cause ground subsidence. In addition, the shield machine attitude adjustment method is also widely used, that is, by adjusting the shield machine attitude so that the floating amount and the offset amount offset each other. However, this method is more dependent on construction experience, and the specific operation is closely related to geological conditions and construction environment, and is more difficult to control.

[0005] After searching the existing technical documents, it was found that the Chinese invention patent with application publication number CN112627851A disclosed a method for preventing the pipe segment from floating up. The method adopts a jacking device composed of a support rod with a spiral head fixed at one end, and fixes one end of the spiral head in the pipe segment hoisting hole, and the other end of the support rod is against the soil layer behind the pipe segment, and grouting is performed between the pipe segment and the soil layer. The slurry wraps the support rod and forms a supporting whole after solidification. The support rod can support the pipe segment and prevent it from floating up. However, although the jacking device and the slurry described in the patent can effectively support the pipe segment after solidification, the support rod is permanently left between the pipe segment and the stratum, which is easy to cause stress concentration in the pipe segment, resulting in quality problems such as cracking and broken corners of the pipe segment.

[0006] Another Chinese invention patent with application publication number CN108301842A discloses a fixing device and construction method for controlling the floating of shield tunnel segments. This method uses multiple anti-floating piles arranged in sequence along the shield tunnel route to constrain the segments by using the friction between the piles and the strata. However, this method requires large-scale pile foundation construction equipment with low cost performance, and cannot take into account the grouting effect. It is easy to cause excessive thrust of shield tunneling, resulting in segment breakage, etc. Moreover, the construction of these patents is mainly based on the experience of construction technicians, and no corresponding design methods are proposed.

[0007] In summary, the existing methods for preventing pipe segments from floating up are inefficient, the construction process is complicated and time-consuming, and there are safety hazards in the later tunnel operation, and the reliability is poor. Therefore, it is urgent to propose a simple and efficient construction method for preventing pipe segments from floating up in shield tunnels. Summary of the invention

[0008] In view of the defects in the prior art, the purpose of the present invention is to provide a construction method suitable for preventing pipe segments from floating up in water-rich rock formations. This method overcomes the shortcomings and deficiencies of the prior art, such as complicated construction process and failure to consider the scouring effect of groundwater in hard rock formations. At the same time, it can prevent the floating of tunnel segments in hard rock formations and improve the quality of slurry filling in the gaps behind the segment wall.

[0009] According to one aspect of the present invention, a construction method for preventing pipe segments from floating up in water-rich rock formations is provided, comprising:

[0010] Embed a threaded sleeve in the reserved grouting hole of the pipe segment;

[0011] Arrange the vertical heights of the grouting holes of each ring of formed segments from high to low, and determine the grouting holes No. 1, No. 2 and No. 3 respectively. After the formed segments are removed from the shield tail, insert the screw rods into the threaded sleeves of the grouting holes No. 1, No. 2 and No. 3 respectively until one end of the screw rod contacts the rock formation behind the segment wall, and fix the screw rod;

[0012] After the trolley reaches the position of the formed segment, the screw rod is taken out from the No. 2 grouting hole and the No. 3 grouting hole, and secondary grouting is performed through the No. 2 grouting hole and the No. 3 grouting hole;

[0013] Take out the screw rod in No. 1 grouting hole, and observe whether the secondary grouting quality meets the requirements through No. 1 grouting hole;

[0014] If the secondary grouting quality does not meet the requirements, insert the screw into grouting hole No. 1, return to the step of performing secondary grouting through grouting hole No. 2 and grouting hole No. 3; if the secondary grouting quality meets the requirements, seal grouting hole No. 1, grouting hole No. 2 and grouting hole No. 3 respectively, and wait for the slurry to completely solidify.

[0015] Furthermore, the threaded sleeve is a steel sleeve having a thread of fixed length on its inner wall along the radial direction of the segment;

[0016] The threaded sleeve is buried in the reserved grouting hole of the pipe segment, including: in the process of prefabricating the pipe segment, a steel sleeve is fixed to the hole mouth of the reserved grouting hole, one end of the steel sleeve is flush with the hole mouth of the grouting hole, and is formed by casting.

[0017] Furthermore, the diameter of the steel sleeve matches the diameter of the reserved grouting hole of the segment; the length of the thread of the steel sleeve along the radial direction of the segment is determined by the following formula:

[0018]

[0019] Where l is the radial length of the steel sleeve thread along the segment, d is the inner diameter of the segment, and T is the segment thickness.

[0020] Furthermore, the screw rod comprises an annular steel bar, a positioning nut and a fixing nut; the positioning nut and the fixing nut are both sleeved on the annular steel bar, and the fixing nut is arranged close to the end of the annular steel bar;

[0021] The fixing screw rod comprises: passing the annular steel bar through the grouting hole, then connecting the positioning nut and the threaded sleeve by threading, and then rotating the fixing nut in the direction of the positioning nut until the positioning nut is in close contact with the fixing nut.

[0022] Furthermore, the outer wall of the annular steel bar is a threaded structure, the diameter of the annular steel bar is smaller than the diameter of the threaded sleeve, and the length of the annular steel bar is determined by the following formula:

[0023] L=D+Td'

[0024] Where L is the length of the annular reinforcement, d' is the outer diameter of the segment, T is the segment thickness, and D is the tunnel excavation diameter.

[0025] Furthermore, the inner wall and the outer wall of the positioning nut are both threaded structures, wherein the inner wall diameter of the positioning nut is equal to the diameter of the annular steel bar, the outer wall diameter of the positioning nut is equal to the inner wall diameter of the threaded sleeve, and the outer wall of the positioning nut is connected to the inner wall of the threaded sleeve by a threaded connection.

[0026] Furthermore, the inner wall of the fixing nut is a threaded structure, and the inner wall diameter of the fixing nut is equal to the outer wall diameter of the annular steel bar.

[0027] Further, the removing the screw rod from the No. 2 grouting hole and the No. 3 grouting hole comprises: rotating the fixing nut in a direction away from the pipe segment, unscrewing the positioning nut from the threaded sleeve, and then removing the screw rod from the corresponding grouting hole;

[0028] The secondary grouting includes: connecting the grouting head with the threaded sleeve in the grouting hole, and injecting slurry into the grouting hole.

[0029] Furthermore, the grouting head includes a retaining nut and a ball valve connected to an external grouting pipe. The outer wall of the retaining nut is a threaded structure. The outer wall of the retaining nut is threadedly connected to the threaded sleeve. A valve for controlling the grouting pressure is also installed on the ball valve.

[0030] Further, observing whether the secondary grouting quality meets the requirements through the No. 1 grouting hole includes:

[0031] If the slurry can be observed through the No. 1 grouting hole and the slurry is uniform and full, the secondary grouting quality meets the requirements;

[0032] If the slurry cannot be observed through grouting hole No. 1, there are voids behind the segment wall, and air and water leakage occur, then the quality of the secondary grouting does not meet the requirements.

[0033] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0034] The present invention provides a construction method for preventing pipe segments from floating up, which is suitable for water-rich rock formations. A threaded sleeve is buried in a reserved grouting hole of the pipe segment. After the formed pipe segment is removed from the shield tail, the screw rod is inserted into the threaded sleeve respectively. The screw rod and the threaded sleeve of the pipe segment embedded part form a matching device, which can judge the grouting effect and facilitate secondary grouting behind the pipe segment wall. The present invention simplifies the operation process of the construction site, can improve the forming quality of the shield tunnel pipe segment in the hard rock formation, and makes up for the shortcomings and deficiencies of the prior art, such as cumbersome construction operation and failure to consider the influence of groundwater flushing on the grouting effect during the grouting process, and has a high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0036] Figure 1 Schematic diagram of the structure of the supporting segment in an embodiment of the present invention;

[0037] Figure 2 It is a structural schematic diagram of the screw rod in an embodiment of the present invention;

[0038] Figure 3 It is a schematic diagram of the structure of a grouting head in an embodiment of the present invention;

[0039] In the figure: 1 is a pipe segment, 2 is a rock layer, 3 is a screw rod, 4 is a grouting hole No. 1, 5 is a grouting hole No. 2, 6 is a grouting hole No. 3, 7 is a ring steel bar, 8 is a positioning nut, 9 is a fastening nut, 10 is a retaining nut, and 11 is a ball valve. DETAILED DESCRIPTION

[0040] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention. In the description of the embodiments of the present invention, it should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0041] In order to ensure the economy, practicality and safety of shield tunnel construction, an embodiment of the present invention provides a construction method for preventing pipe segments from floating up in water-rich rock formations, the method comprising:

[0042] S1. Embed a threaded sleeve in the reserved grouting hole of the pipe segment.

[0043] In some specific embodiments, the threaded sleeve is a steel sleeve having a fixed length of thread on its inner wall along the radial direction of the segment. The threaded sleeve is buried in the reserved grouting hole of the segment, specifically comprising: during the segment prefabrication process, the steel sleeve is fixed to the hole of the reserved grouting hole, one end of the steel sleeve is flush with the hole of the grouting hole, and is formed by casting.

[0044] In order to select a suitable steel sleeve, in some preferred embodiments, the diameter of the steel sleeve matches the diameter of the reserved grouting hole of the segment; the length of the thread of the steel sleeve along the radial direction of the segment is determined by the following formula:

[0045]

[0046] Where l is the radial length of the steel sleeve thread along the segment, d is the inner diameter of the segment, and T is the segment thickness.

[0047] Specifically, taking a circular shield tunnel as an example, the excavation diameter is 9.2m, the inner diameter of the segment is 8m, the outer diameter of the segment is 8.8m, the thickness of the segment is 0.4m, and the mileage interval DXK10+560-DXK10+720 is a medium-weathered granite stratum with a uniaxial compressive strength of 90MPa-120MPa, which is a hard rock stratum. During the full-section hard rock normal pressure excavation process, the groundwater is abundant, and the gap filling effect after the synchronous grouting of the segment wall is poor. The hard rock segment floats and ellipses. A large number of broken corners appear in the segment, causing the formed tunnel to exceed the limit and quality defects. The method in this embodiment is used for construction. Since the inner diameter of the segment is 8m and the thickness of the segment is 0.4m, according to calculations, the length l of the threaded sleeve thread along the radial direction of the segment is 2cm.

[0048] S2. Arrange the vertical heights of the grouting holes of each ring segment 1 from high to low, and determine the grouting holes No. 1, No. 2 and No. 3, which are the grouting holes arranged in the first three vertical heights, with reference to Figure 1 As shown, grouting hole No. 1 4, grouting hole No. 2 5, and grouting hole No. 3 6 respectively refer to the grouting holes with the first, second, and third largest vertical heights in each ring of the segment 1; after the segment 1 is removed from the shield tail, the screw rod 3 is respectively inserted into the threaded sleeves of grouting hole No. 1 4, grouting hole No. 2 5, and grouting hole No. 3 6 until one end of the screw rod 3 contacts the rock layer 2 behind the wall of the segment 1, and the screw rod 3 is fixed.

[0049] In some specific embodiments, reference Figure 2 As shown, the screw rod 3 includes an annular steel bar 7, a positioning nut 8 and a fixing nut 9; wherein the annular steel bar 7 is used to pass through the grouting hole, the positioning nut 8 and the fixing nut 9 are both sleeved on the annular steel bar 7, and the fixing nut 9 is arranged near the end of the annular steel bar 7. Fixing the screw rod 3 specifically includes: passing the annular steel bar 7 through the grouting hole, then connecting the positioning nut 8 with the threaded sleeve by threading, and then rotating the fixing nut 9 in the direction of the positioning nut 8 until the positioning nut 8 is in close contact with the fixing nut 9, so that the screw rod 3 is fixed.

[0050] In some specific embodiments, the outer wall of the annular reinforcement 7 is a threaded structure, and the diameter of the annular reinforcement 7 is smaller than the diameter of the threaded sleeve, so that the annular reinforcement 7 can pass through the grouting hole, and the length of the annular reinforcement 7 is determined by the following formula:

[0051] L=D+Td'

[0052] Where L is the length of the annular reinforcement, d' is the outer diameter of the segment, T is the segment thickness, and D is the tunnel excavation diameter.

[0053] In some specific embodiments, the inner wall and outer wall of the positioning nut 8 are both threaded structures, wherein the inner wall diameter of the positioning nut 8 is equal to the diameter of the annular steel bar 7, the outer wall diameter of the positioning nut 8 is equal to the inner wall diameter of the threaded sleeve, and the outer wall of the positioning nut 8 is connected to the inner wall of the threaded sleeve by a threaded connection.

[0054] In some specific embodiments, the inner wall of the fastening nut 9 is a threaded structure, and the inner wall diameter of the fastening nut 9 is equal to the outer wall diameter of the annular steel bar 7 .

[0055] For the circular shield tunnel mentioned above, in order to allow the annular reinforcement to pass through the grouting holes of the segments, the diameter of the outer wall thread structure of the annular reinforcement is 30mm; the outer diameter d' of the segment is 8.8m, the thickness T of the segment is 0.4m, and the tunnel excavation diameter D is 9.2m. The calculated length L of the annular reinforcement is 0.8m. The inner wall diameter of the positioning nut is equal to the diameter of the annular reinforcement, both of which are 30mm, and the outer wall thread diameter is equal to the inner wall thread diameter of the threaded sleeve, both of which are 44mm. The thread structure diameter of the inner wall of the fixing nut is 30mm, and the outer diameter of the fixing nut is 50mm. Connect the positioning nut to the inner wall of the threaded sleeve through threads, and rotate the fixing nut toward the positioning nut until it is in close contact with the positioning nut, thereby fixing the screw.

[0056] S3. After the trolley reaches the position of forming the segment, specifically, the rear supporting equipment of the shield machine is usually placed on the trolley and numbered from near to far according to the distance between the trolley and the cutterhead. After the corresponding trolley, such as trolley No. 2, reaches the position of forming the segment, the screw rod 3 is taken out from grouting hole No. 2 5 and grouting hole No. 3 6, and secondary grouting is carried out through grouting hole No. 2 5 and grouting hole No. 3 6.

[0057] In some specific embodiments, removing the screw rod 3 from grouting hole No. 2 5 and grouting hole No. 3 6 includes: rotating the fastening nut 9 away from the segment 1, unscrewing the positioning nut 8 from the threaded sleeve, and then removing the screw rod 3 from the corresponding grouting hole; the secondary grouting includes: connecting the grouting head to the threaded sleeve in the grouting hole, and injecting slurry into the grouting hole.

[0058] Reference Figure 3 As shown, the grouting head includes a locking nut 10 and a ball valve 11 connected to an external grouting pipe. The ball valve 11 can be connected to the external grouting pipe by threaded connection, so as to perform grouting operation. The outer wall of the locking nut 10 is a threaded structure, and its diameter matches the thread of the threaded sleeve. The outer wall of the locking nut 10 is connected to the threaded sleeve by threads, and a valve for controlling the grouting pressure is also installed on the ball valve 11.

[0059] S4. Take out the screw in the No. 1 grouting hole 4, and observe whether the secondary grouting quality meets the requirements through the No. 1 grouting hole 4.

[0060] This step is mainly to check the grouting effect, that is, after the screw 3 is taken out, the secondary grouting quality is observed through the No. 1 grouting hole 4. If the slurry can be observed through the No. 1 grouting hole 4, and the slurry is uniform and full, the secondary grouting quality meets the requirements. If the slurry cannot be observed through the No. 1 grouting hole 4, there are cavities behind the wall of the segment, and there are air leakage, water leakage and other phenomena, the secondary grouting quality does not meet the requirements.

[0061] It should be noted that the operation process of taking out the screw rod 3 from the No. 1 grouting hole 4 is the same as the operation process of taking out the screw rod 3 from the No. 2 grouting hole 5 and the No. 3 grouting hole 6 in step S3, and will not be repeated here.

[0062] S5. If the secondary grouting quality does not meet the requirements, insert the screw rod 3 into the No. 1 grouting hole 4, return to and perform secondary grouting through the No. 2 grouting hole 5 and the No. 3 grouting hole 6, that is, insert the screw rod 3 into the No. 1 grouting hole 4, and continue grouting through the No. 2 grouting hole 5 and the No. 3 grouting hole 6, and check the grouting effect until the secondary grouting quality meets the requirements; if the secondary grouting quality meets the requirements, seal the No. 1 grouting hole 4, the No. 2 grouting hole 5 and the No. 3 grouting hole 6 respectively, and wait for the slurry to completely solidify.

[0063] The construction method for preventing pipe segments from floating up in water-rich rock formations in the embodiment of the present invention is as follows: threaded sleeves are buried in grouting holes reserved in the pipe segments; after the formed pipe segments are removed from the shield tails, screw rods are respectively inserted into the threaded sleeves; a matching device is formed by the screw rods and the threaded sleeves of the embedded parts of the pipe segments; the grouting effect can be judged and secondary grouting behind the pipe segment wall is convenient; the method is simple and easy to operate, has high reliability, effectively solves the problem of groundwater scouring in hard rock formations, can improve the forming quality of shield tunnel pipe segments in hard rock formations, and has good social and economic benefits.

[0064] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various modifications or variations within the scope of the claims, which does not affect the essence of the present invention. The above preferred features can be used in any combination without conflicting with each other.

Claims

1. A construction method for preventing pipe segments from floating up in water-rich rock formations, characterized in that: include: Embed a threaded sleeve in the reserved grouting hole of the pipe segment; Arrange the vertical heights of the grouting holes of each ring of formed segments from high to low, and determine the grouting holes No. 1, No. 2 and No. 3 respectively. After the formed segments are removed from the shield tail, insert the screw rods into the threaded sleeves of the grouting holes No. 1, No. 2 and No. 3 respectively until one end of the screw rod contacts the rock formation behind the segment wall, and fix the screw rod; After the trolley reaches the position of the formed segment, the screw rod is taken out from the No. 2 grouting hole and the No. 3 grouting hole, and secondary grouting is performed through the No. 2 grouting hole and the No. 3 grouting hole; Take out the screw rod in No. 1 grouting hole, and observe whether the secondary grouting quality meets the requirements through No. 1 grouting hole; If the secondary grouting quality does not meet the requirements, insert the screw into the No. 1 grouting hole, return to the step of performing secondary grouting through the No. 2 grouting hole and the No. 3 grouting hole; if the secondary grouting quality meets the requirements, seal the No. 1 grouting hole, the No. 2 grouting hole and the No. 3 grouting hole respectively, and wait for the slurry to completely solidify; in: The threaded sleeve is a steel sleeve having a fixed length of thread on its inner wall along the radial direction of the segment; The threaded sleeve is buried in the reserved grouting hole of the pipe segment, including: in the process of prefabricating the pipe segment, a steel sleeve is fixed to the hole of the reserved grouting hole, one end of the steel sleeve is flush with the hole of the grouting hole, and is formed by casting; The diameter of the steel sleeve matches the diameter of the reserved grouting hole of the segment; the length of the thread of the steel sleeve along the radial direction of the segment is determined by the following formula: Where, l is the length of the steel sleeve thread along the radial direction of the segment, d is the inner diameter of the segment, and T is the thickness of the segment; The screw rod comprises an annular steel bar, a positioning nut and a fixing nut; the positioning nut and the fixing nut are both sleeved on the annular steel bar, and the fixing nut is arranged close to the end of the annular steel bar; The fixing screw rod comprises: passing the annular steel bar through the grouting hole, then connecting the positioning nut and the threaded sleeve by threading, and then rotating the fixing nut in the direction of the positioning nut until the positioning nut is in close contact with the fixing nut; The secondary grouting comprises: connecting the grouting head with the threaded sleeve in the grouting hole, and injecting slurry into the grouting hole; The grouting head comprises a retaining nut and a ball valve connected to an external grouting pipe. The outer wall of the retaining nut is a threaded structure, and the outer wall of the retaining nut is connected to the threaded sleeve through threads.

2. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 1, characterized in that: The outer wall of the annular steel bar is a threaded structure, the diameter of the annular steel bar is smaller than the diameter of the threaded sleeve, and the length of the annular steel bar is determined by the following formula: L=D+T-d ′ Where L is the length of the ring reinforcement, d ′ is the outer diameter of the segment, T is the thickness of the segment, and D is the tunnel excavation diameter.

3. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 2 is characterized in that: The inner wall and outer wall of the positioning nut are both threaded structures, wherein the inner wall diameter of the positioning nut is equal to the diameter of the annular steel bar, the outer wall diameter of the positioning nut is equal to the inner wall diameter of the threaded sleeve, and the outer wall of the positioning nut is connected to the inner wall of the threaded sleeve by a threaded connection.

4. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 3 is characterized in that: The inner wall of the fixing nut is a threaded structure, and the inner wall diameter of the fixing nut is equal to the outer wall diameter of the annular steel bar.

5. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 1, characterized in that: The method of removing the screw rod from the No. 2 grouting hole and the No. 3 grouting hole includes: rotating the fixing nut in a direction away from the pipe segment, unscrewing the positioning nut from the threaded sleeve, and then removing the screw rod from the corresponding grouting hole.

6. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 5 is characterized in that: The ball valve is also provided with a valve for controlling the grouting pressure.

7. The construction method for preventing pipe segments from floating up in water-rich rock formations according to claim 1, characterized in that: The observation of whether the secondary grouting quality meets the requirements through the No. 1 grouting hole includes: If the slurry can be observed through the No. 1 grouting hole and the slurry is uniform and full, the secondary grouting quality meets the requirements; If the slurry cannot be observed through grouting hole No. 1, there are voids behind the segment wall, and air and water leakage occur, then the quality of the secondary grouting does not meet the requirements.

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