Water-rich sand layer shield tunnel leakage water treatment method and drilling and injection integrated device

Abstract

A water-rich sand layer shield tunnel leakage water treatment method and drilling and injecting integrated device, the method forms a grouting outer ring through the drilling and injecting integrated device construction, and then adopts a micro-disturbance grouting technology to penetrate and reinforce an inner ring area, forms a second grouting reinforcement ring, and realizes the treatment of water-rich sand layer shield tunnel leakage water.The beneficial effects of the present application are that the self-excited oscillation pulse structure adopted by the drilling and injecting integrated device can greatly improve the diffusion radius of the slurry in the soil, solve the problems of uneven diffusion of the slurry in the soil and away from the shield segment lining direction, and improve the grouting reinforcement effect;the partition ring is provided with a water outlet hole, which can prevent the pore pressure from being too large during the grouting process, causing the segment to be misaligned, and even causing the segment to be cracked and damaged in severe cases;the cement-water glass double-liquid slurry and cement single-liquid slurry are alternately grouted, which can save the amount of water glass, improve the economic benefit, and ensure the strength of the reinforced body.

Description

Technical Field

[0001] This invention relates to a method for treating water leakage in shield tunnels with water-rich sand layers and an integrated drilling and injection device, belonging to the field of shield tunnel engineering technology. Background Technology

[0002] Subways, as an underground transportation mode, can effectively alleviate surface traffic congestion and are an important part of regional development, with many cities in my country having them. Shield tunnel segment lining is the main structural type of subway tunnels. However, as subway tunnels age, their structural performance begins to decline, and various defects appear under the combined effects of complex external environments, with water leakage being the most common. Grouting, as an effective means of controlling water damage, has been increasingly widely used in the treatment of water leakage in subway tunnels. However, existing grouting technologies are not yet mature enough, and are affected by external loads and geological conditions, resulting in less than ideal grouting effects. There are two main problems with grouting outside the shield tunnel lining in water-rich sandy layers: 1) uneven grout diffusion and poor reinforcement effect; 2) the grout tends to diffuse away from the shield tunnel lining, causing significant waste.

[0003] Publication No. CN109339824A discloses a method for treating water leakage in shield tunnel segments. This method determines different treatment methods based on the location and form of leakage as determined by on-site statistics: leakage from segment circumferential and longitudinal joints and bolt holes is treated by injecting epoxy resin grouting material; leakage from segment grouting holes is treated by back-wall grouting or epoxy resin grouting material. However, this method cannot fundamentally solve the problem of segment water leakage. Publication No. CN215565926U discloses a grouting device for advanced geological drilling in shield tunnels. This device includes grouting pipelines, drill rod assemblies, a controller, and a positioning seat. Although this device can achieve integrated drilling and grouting, it cannot form an effective, completely closed grouting outer ring, failing to solve the problem of grout diffusion away from the shield lining. Furthermore, it cannot achieve micro-disturbance grouting technology to penetrate and reinforce the inner ring area, ensuring the effectiveness of grouting. Summary of the Invention

[0004] The purpose of this invention is to address the problems of uneven grout diffusion and poor reinforcement effect in the treatment of water leakage in shield tunnels with water-rich sand layers, and the tendency of grout to diffuse away from the shield tunnel lining, resulting in a large amount of waste. This invention proposes a method for treating water leakage in shield tunnels with water-rich sand layers and an integrated drilling and grouting device.

[0005] The technical solution for achieving this invention is as follows: A method for treating water leakage in a shield tunnel with a water-rich sand layer, wherein the method involves constructing an outer grouting ring using an integrated drilling and grouting device, and then using micro-disturbance grouting technology to penetrate and reinforce the inner ring area, forming a second grouting reinforcement ring, thereby treating water leakage in the shield tunnel with a water-rich sand layer; after determining the location of the leakage segment, a cement grout with a certain water-cement ratio and a cement-water glass dual-liquid grout with a certain volume ratio are prepared; the integrated drilling and grouting device is used to drill in the selected grouting hole, and drilling is stopped when the drilling depth reaches a certain depth; the grouting joint and grouting pipe are then connected. Grouting was carried out sequentially on the outer and inner rings. The outer ring grouting adopted a self-excited oscillation pulse grouting process, supplemented by a rotating rod extraction method to form the grouting outer ring. The inner ring grouting adopted a micro-disturbance grouting process to penetrate and reinforce the inner ring area, supplemented by alternating grouting methods of cement-water glass double-liquid grout and cement single-liquid grout. Drainage holes were set in the partition ring to prevent excessive pore pressure during grouting, which could cause segment misalignment or even segment cracking in severe cases. At the same time as grouting, the ball valve of the drainage hole parallel to the grouting hole was opened to release water pressure, and the convergence deformation of the segment was monitored in real time with a total station until the grouting was completed.

[0006] A method for treating water leakage in shield tunnels with water-rich sand layers, the specific steps of which are as follows: (1) Determine the location of the leaking pipe segment, relocate the pipeline, and clean the surface of the entire ring grouting hole.

[0007] (2) Install check valves and ball valves at the grouting hole: First, screw 1 to 2 check valves into the grouting hole, then tighten the pre-prepared φ50mm threaded wire to the grouting hole, and finally install φ50mm ball valves at the end of the grouting hole.

[0008] (3) Prepare cement slurry with a water-cement ratio of 0.8 to 1.0 and cement-water glass double-liquid slurry with a volume ratio of 1:1; wherein, the cement is 425# ordinary Portland cement; the water glass modulus is 2.8 to 3.4 and the concentration Be' is 35 to 41; in particular, sodium dihydrogen phosphate is added during the preparation of the double-liquid slurry, and the dosage of sodium dihydrogen phosphate is 0.5% to 3% of the cement mass; control the initial setting time of the slurry to be within 30s and the final setting time to be within 10min.

[0009] (3) Use an integrated drilling and grouting device to drill in the selected grouting hole. Stop drilling when the drilling depth reaches 3.6m and connect the grouting joint and grouting pipe.

[0010] (4) Outer ring grouting: The outer ring grouting adopts the self-excited oscillation pulse grouting process and is supplemented by the method of rotating the rod to realize the formation of the grouting outer ring. After the grouting is completed, the drilling and grouting integrated device is pulled out and the ball valve is quickly closed.

[0011] (5) Inner ring grouting: (5-1) Prepare the grout as in step (3), including cement grout and cement-water glass double liquid grout; the initial setting time of the double liquid grout is controlled within 2 minutes and the final setting time is controlled within 15 minutes; the initial setting time of the cement single liquid grout is controlled within 10 minutes and the final setting time is controlled within 40 minutes.

[0012] (5-2) Clean the surface of the drainage hole and install the ball valve; drill holes on the reserved drainage hole of the segment until the entire segment and the outer layer of the tunnel formed by synchronous grouting are completely drilled through; there are a total of 6 drainage holes, separated from the grouting hole by one ring; drainage holes are set in the partition ring to prevent excessive pore pressure during grouting, which may cause segment misalignment or even segment cracking in severe cases.

[0013] (5-3) Open the ball valve of the grouting hole and connect the grouting equipment. Use the micro-disturbance grouting process to penetrate and reinforce the inner ring area. The grouting pressure is 0.2MPa~0.5MPa, and the grouting rate is: cement grout flow rate is 12-14L / min, water glass grout flow rate is 6-8L / min, and mixed grout flow rate is 20L / min.

[0014] (5-4) Grouting method with alternating cement-water glass double liquid grout and cement single liquid grout: First, cement-water glass double liquid grout is injected for 10 minutes; then, cement single liquid grout is injected for 5 minutes; then, cement-water glass double liquid grout is injected again for 5 minutes; finally, cement single liquid grout is injected until the grouting is completed.

[0015] (6) At the same time as grouting, open the ball valve of the drain hole parallel to the grouting hole to release water and use a total station to monitor the convergence deformation of the pipe segment in real time. If the convergence deformation of the pipe segment exceeds 2mm or the grouting pressure rises to 0.6MPa, grouting should be stopped to protect the pipe segment.

[0016] (7) After the construction is completed, clean up the site.

[0017] The self-excited oscillating pulse grouting process parameters are as follows: grouting pressure is 8~10MPa, grouting flow rate is 160~180L / min; rotation speed is 20r / min, and rod extraction speed is 110mm / min. When reinforcing the soil, the self-excited oscillating pulse grouting process can form an effective and completely closed grouting outer ring, which has the effect of preventing the inner ring grout from spreading away from the shield tunnel segment lining.

[0018] An integrated drilling and grouting device for treating water leakage in shield tunnels with water-rich sand layers includes a grouting joint, a grouting main cylinder, and a drill bit. The grouting main cylinder is a cylindrical structure, with one end connected to the drill bit, which is welded to the end where the outlet boundary of the grouting main cylinder is located. The other end is connected to the grouting joint, which is threaded to the end where the inlet boundary of the grouting main cylinder is located.

[0019] The grouting main cylinder consists of a self-excited oscillation pulse structure zone and a grouting chamber. The self-excited oscillation pulse structure zone comprises a chamber, an inlet, an outlet, an upper nozzle, and a lower nozzle. The inlet is connected to the grouting joint through the inlet boundary, and the outlet is connected to the drill bit through the outlet boundary. The chamber diameter is D, the upper nozzle diameter is d1, the lower nozzle diameter is d2, the chamber length is H, and the lower nozzle cone angle is a, with specific values ​​of: D / d2=6.5~8.5, d2 / d1=1.6~2.1, H / D=0.5~0.7, and a=120°. The grouting chamber is adjacent to the outlet boundary of the self-excited oscillation pulse structure zone, and has 5 layers of grouting holes evenly distributed circumferentially on its outer surface. The grouting holes have a diameter of 2mm and a total of 100 holes, which are evenly distributed circumferentially in 5 layers on the outer surface of the grouting chamber, with a spacing of 50mm between each layer.

[0020] The grouting main cylinder has a diameter of 48mm and a length of 3.6m.

[0021] The working principle of the self-excited oscillation pulse structure chamber of the integrated drilling-injection device: (e.g.) Figure 5 The diagram shows a schematic of the self-excited oscillation structure chamber of the integrated drilling-grouting device. Within this chamber, a pair of vortices with periodically varying pressure and magnitude are formed between the collision zone and the grouting cylinder wall. When these vortices collide with the outlet wall, a high-pressure zone is generated, simultaneously producing pressure pulse waves. These waves propagate upstream at the speed of sound, inducing new vorticity pulsations. If the pressure pulsations in the separation zone and the collision zone are out of phase, a cyclical process of vorticity disturbance-amplification-new vorticity pulsation is formed. This process repeats continuously, resulting in a strong self-excited oscillating pulsed grout jet.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The drilling and grouting integrated device of this invention adopts a self-excited oscillation pulse structure, which has the advantages of simple structure, small size and no additional external driving mechanism; and can greatly increase the diffusion radius of grout in the soil, thereby forming an effective and completely closed grouting outer ring. The main functions of the grouting outer ring include: (1) serving as the first grouting reinforcement water-stopping ring; (2) constraining the diffusion range of subsequent micro-disturbance grout, solving the problems of grout diffusion away from the shield tunnel segment lining and uneven diffusion in the soil, and improving the grouting reinforcement effect; the partition ring of this invention is equipped with drainage holes, which can prevent excessive pore pressure during grouting, causing segment misalignment or even segment cracking in severe cases. Damage and other phenomena ensure the service performance of the segment lining structure; at the same time, a negative pressure zone is formed with the drainage hole as the origin, inducing the grout to diffuse towards the drainage hole and increasing the grout diffusion radius; the main advantages of the alternating grouting method of cement-water glass double liquid grout and cement single liquid grout in this invention are: (1) It can save water glass usage and improve economic efficiency; (2) Since the cement-water glass grout has low gel strength, adding cement single liquid grout can effectively improve the strength of the inner ring solidified body; (3) By alternating grouting method of first double liquid grout and then cement single liquid grout, a wrapping layer can be formed, overcoming the problem of easy grout leakage caused by the high fluidity of cement single liquid grout. Attached Figure Description

[0023] Figure 1 This is a flowchart of a method for treating water leakage in a shield tunnel with a water-rich sand layer according to the present invention. Figure 2 This is a schematic diagram of the slurry diffusion cross section of the present invention; Figure 3 This is a schematic diagram of the integrated drilling-injection device of the present invention; Figure 4 This is a schematic diagram of the AA cross-section of the drilling-injection integrated device of the present invention; Figure 5 This is a schematic diagram of the self-excited oscillation structure chamber of the drilling-injection integrated device of the present invention; Figure 6 This is a schematic diagram of the micro-disturbance grouting process of the present invention; Figure 7 This is a schematic diagram of single-hole diffusion in micro-disturbance grouting according to the present invention; Figure 8 This is a diagram showing the layout of monitoring points for the water leakage control method in the shield tunnel of the present invention. Figure 9 A schematic diagram showing the locations for installing check valves and ball valves at grouting holes; Figure 10 This indicates the location of the grouting holes and drainage holes on the tunnel lining segments; In the diagram, 1 is the tunnel segment; 2 is the inner grouting ring; 2-1 is the cement-water glass grout diffusion zone; 2-2 is the cement grout diffusion zone; 3 is the outer grouting ring; 4 is the grouting hole; 5 is the drainage hole; 6 is the spray hole; 7 is the drill bit; 8 is the grouting main cylinder; 8-1 is the self-excited oscillation pulse structure; 8-2 is the grouting chamber; 9 is the grouting joint; 10 is the grouting pipe; 11 is the mixer; 12 is the grouting pump; 13 is the flow meter; 14 is the pressure gauge; 15 is the valve; 16 is the first grout storage tank; 17 is the second grout storage tank; and 18 is the monitoring point. Detailed Implementation

[0024] Specific embodiments of the present invention are as follows: Figure 1 The process is shown below.

[0025] This embodiment

[0026] A method for treating water leakage in shield tunnels with water-rich sand layers, the specific steps of which are as follows: S1: Determine the location of the leaking pipe segment, relocate the pipeline, and clean the surface of the entire ring of grouting holes.

[0027] S2: As Figure 9 As shown, install check valves and ball valves at the grouting hole: first screw 1-2 check valves into the grouting hole, then tighten the pre-prepared φ50mm threaded rods to the grouting hole, and finally install the φ50mm ball valve at the end of the grouting hole.

[0028] S3: Prepare a cement-water glass two-component grout with a water-cement ratio of 0.8~1.0 and a volume ratio of 1:1. The cement used is 425# ordinary Portland cement; the water glass modulus is 2.8~3.4, and the concentration (Be') is 35~41. Specifically, sodium dihydrogen phosphate is added during the preparation of the two-component grout, with an admixture amount of 0.5%~3% of the cement mass; the initial setting time of the grout is controlled within 30 seconds, and the final setting time within 10 minutes.

[0029] Considering the impact of groundwater dilution on the grout, the mixing ratio can be finely adjusted on-site to meet project requirements.

[0030] S4: Drilling is performed in the selected grouting hole 4 using an integrated drilling-grouting device. Drilling is stopped when the drilling depth reaches 3.6m, and the grouting joint 9 and grouting pipe 10 are connected. For example... Figure 3 and Figure 6 As shown.

[0031] S5: Outer Ring Grouting: This grouting process uses a self-excited oscillation pulse grouting technique, supplemented by a rotating rod extraction method to achieve the formation of the outer ring 3. Figure 2 As shown; after grouting is completed, pull out the drilling-grouting integrated device and quickly close the ball valve.

[0032] Specifically, the grouting pressure is 8~10MPa, the grouting flow rate is 160~180L / min, the rotation speed is 20r / min, and the rod extraction speed is 110mm / min.

[0033] Specifically, the grouting duration for each grouting hole 4 is 10 minutes, and the grouting sequence is shifted from the top grouting hole 4 to both sides, proceeding symmetrically.

[0034] S6: Inner ring grouting S6-1: Prepare the grout, including cement grout and cement-water glass two-component grout, and the preparation method is the same as S3 above. The water-cement ratio of the cement grout is 0.8~1.0; the volume ratio of the cement-water glass two-component grout is 1:1.

[0035] Specifically, the initial setting time of the two-component grout is controlled within 2 minutes, and the final setting time is controlled within 15 minutes; the initial setting time of the single-component cement grout is controlled within 10 minutes, and the final setting time is controlled within 40 minutes. In addition, due to the short tunnel window period, the grouting time of the inner ring is one day apart from that of the outer ring.

[0036] S6-2: Clean the surface of drainage hole 5 and install the ball valve. Then, use an electric impact drill to drill through the entire segment 1 and the outer layer of the tunnel formed by synchronous grouting. After drilling is completed, two people work together: one pulls out the electric impact drill, and the other quickly closes the ball valve.

[0037] Specifically, there are 6 drainage holes (5 in total), which are separated from grouting holes (4) by one ring, such as... Figure 10 As shown.

[0038] S6-3: As Figure 6 As shown, the ball valve of grouting hole 4 is opened to connect the grouting equipment, and the inner ring area is reinforced using a micro-disturbance grouting process. Specifically, the grouting pressure is set to 0.2MPa~0.5MPa, and the grouting rates are: cement grout flow rate of 12-14L / min, water glass grout flow rate of 6-8L / min, and mixed grout flow rate of 20L / min. A schematic diagram of single-hole diffusion in micro-disturbance grouting in this embodiment is shown below. Figure 7 As shown.

[0039] S6-4: An alternating grouting method using cement-water glass dual-component grout and cement single-component grout is adopted. Specifically, first, cement-water glass dual-component grout is injected for 10 minutes; second, cement single-component grout is injected for 5 minutes; then, cement-water glass dual-component grout is injected again for 5 minutes; finally, cement single-component grout is injected until the grouting is completed.

[0040] Specifically, the grouting sequence is consistent with that of the outer ring grouting, starting with the top grouting holes and then the side grouting holes, proceeding symmetrically.

[0041] S7: Simultaneously with grouting, open the ball valve of the drain hole 5 parallel to the grouting hole 4 to release pressure and allow water to flow out, and use a total station to monitor the convergence deformation of segment 1 in real time; the specific locations of monitoring points 18 are as follows: Figure 8 As shown, there are four drainage holes, located at the 2 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock positions inside segment 1. When turbid grout appears in drainage hole 5, indicating grout leakage, continue grouting for 2 minutes, then stop grouting and close the ball valves of grouting hole 4 and drainage hole 5. Specifically, if the segment's convergence deformation exceeds 2 mm or the grouting pressure rises to 0.6 MPa, grouting should be stopped to protect segment 1. Furthermore, during each grouting cycle, the interval should be greater than or equal to 5 cycles, and the interval between grouting cycles in the same hole should be at least 72 hours.

[0042] S8: Construction completed, site cleaned up.

[0043] The structure of the integrated drilling and injection device in this embodiment is as follows: Figure 3 and Figure 4 As shown. The integrated drilling and grouting device includes a grouting joint 9, a grouting main cylinder 8, and a drill bit 7.

[0044] The grouting main cylinder 8 consists of a self-excited oscillation pulse structure chamber 8-1 and a grouting chamber 8-2, such as Figure 4 and Figure 5 As shown; the self-excited oscillation pulse structure chamber 8-1 consists of an upper nozzle and a lower nozzle; the upper nozzle is a circular hole formed by the upper base of an isosceles trapezoid with a cross-section surrounding the inner wall of the grouting main cylinder, with a diameter of d1 and a length of B, B=10cm; the lower nozzle is a circular hole formed by one side of a parallelogram with a cross-section surrounding the inner wall of the grouting main cylinder, with a diameter of d2 and a length of C, C=8cm; the upper nozzle is located above the grouting main cylinder for a length of... F, F=290cm; the length of the grouting main cylinder below the lower nozzle is E, E=30cm; the cavity between the upper and lower nozzles has a diameter of D and a length of H; the upper inclined surface of the lower nozzle is the collision zone, the cone angle of the lower nozzle formed by the cone surface of the collision zone is a, and the angle between the collision zone and the inner wall of the grouting main cylinder is a / 2; where D / d2=6.5~8.5; d2 / d1=1.6~2.1; H / D=0.5~0.7; a=120°.

[0045] Grouting chamber 8-2 is adjacent to the outlet boundary of self-excited oscillation pulse structure chamber 8-1, and five layers of grouting holes 6 are evenly distributed around its outer surface. The diameter of the grouting holes 6 is 2mm, and there are a total of 100 holes, which are evenly distributed around the outer surface of grouting chamber 8-2 in five layers, with a spacing of 50mm between each layer.

[0046] The grouting joint 9 is threaded to the end of the grouting main cylinder 8 at the inlet boundary. The drill bit 7 is made of hard alloy material and is welded to the end of the grouting main cylinder 8 at the outlet boundary.

[0047] like Figure 5As shown, within the self-excited oscillating pulse structure chamber 8-1, a pair of vortices with periodically varying pressure and magnitude are formed between the collision zone and the grouting cylinder wall. When these vortices collide with the outlet wall, a high-pressure zone is generated, simultaneously producing pressure pulse waves. These waves propagate upstream at the speed of sound, inducing new vorticity pulsations. If the pressure pulsations in the separation zone and the collision zone are out of phase, a cyclic process of vorticity disturbance-amplification-new vorticity pulsation is formed. This process repeats continuously, resulting in a strong self-excited oscillating pulse grout jet, which can significantly increase the diffusion radius of the grout in the soil.

[0048] Figure 6 The diagram shows a micro-disturbance grouting process according to this embodiment. Grouting hole 4 is the grouting hole on segment 1. The first grout storage tank 16 and the second grout storage tank 17 enter the mixer 11 through the grouting pump 12, valve 15, flow meter 13, pressure gauge 14, and grouting pipe 10, respectively, and grout is injected into the grouting hole from the mixer 11. The first grout storage tank 16 and the second grout storage tank 17 are respectively filled with cement-water glass double-liquid grout and cement single-liquid grout, enabling alternating grouting.

[0049] The overall cross-section of the slurry diffusion in an embodiment of the present invention is as follows: Figure 2 As shown, 1 is the tunnel segment, 2 is the inner grouting ring, and 3 is the outer grouting ring. With the center of tunnel segment 1 as the center, the radius of tunnel segment 1 is 3m; the maximum radius of the inner grouting ring 2 is 5.4m, and the thickness of the inner grouting ring 2 is 2.4m; the maximum radius of the outer grouting ring 3 is 6.5m, and the thickness of the outer grouting ring is 1.1m.

[0050] Figure 7 The diagram shown is a schematic diagram of single-hole diffusion in micro-disturbance grouting according to this embodiment. In the diagram, 1 is the pipe segment; 2 is the inner ring of grouting; 2-1 is the cement-water glass grout diffusion zone; 2-2 is the cement grout diffusion zone; this is the effect produced by alternating grouting in the inner ring 2.

Claims

1. A method for treating water leakage in a water-rich sand layer shield tunnel, characterized by, The method involves constructing an outer grouting ring using an integrated drilling and grouting device, followed by micro-disturbance grouting technology to penetrate and reinforce the inner ring area, forming a second grouting reinforcement ring to address water leakage in shield tunnels with water-rich sand layers. The outer ring grouting employs a self-excited oscillating pulse grouting process, supplemented by a rotating rod extraction method to achieve the outer grouting ring formation. The inner ring grouting uses a micro-disturbance grouting process to penetrate and reinforce the inner ring area, supplemented by alternating grouting methods of cement-water glass dual-liquid grout and cement single-liquid grout. Simultaneously with grouting, a ball valve at a drainage hole parallel to the grouting hole is opened to release pressure and allow water to flow out. A total station is used to monitor the segment convergence and deformation in real time until the grouting is completed. The specific steps of the method are as follows: (1) Determine the location of the leaking pipe segment, relocate the pipeline, and clean the surface of the entire ring of grouting holes; (2) Install check valves and grouting hole ball valves at the grouting hole: First, screw 1 to 2 check valves into the grouting hole, then tighten the pre-prepared φ50mm threaded wire to the grouting hole, and finally install φ50mm grouting hole ball valves at the end of the grouting hole. (3) Prepare a single-liquid cement slurry with a water-cement ratio of 0.8 to 1.0 and a double-liquid cement-water glass slurry with a volume ratio of 1:1; wherein, the cement is 425# ordinary Portland cement; the water glass modulus is 2.8 to 3.4 and the concentration Be' is 35 to 41; sodium dihydrogen phosphate is added during the preparation of the double-liquid slurry, and the amount of sodium dihydrogen phosphate is 0.5% to 3% of the cement mass; control the initial setting time of the slurry to be within 30s and the final setting time to be within 10min; (3) Drilling is carried out in the selected grouting hole using an integrated drilling and grouting device. Drilling is stopped when the drilling depth reaches 3.6m, and the grouting joint and grouting pipe are connected. (4) Outer ring grouting: The outer ring grouting adopts the self-excited oscillation pulse grouting process and is supplemented by the method of rotating the rod to realize the formation of the grouting outer ring. After the grouting is completed, the drilling and grouting integrated device is pulled out and the ball valve of the grouting hole is quickly closed. (5) Inner ring grouting: (5-1) Prepare the grout as in step (3), including cement single-liquid grout and cement-water glass double-liquid grout; the initial setting time of the double-liquid grout is controlled within 2 minutes and the final setting time is controlled within 15 minutes; the initial setting time of the cement single-liquid grout is controlled within 10 minutes and the final setting time is controlled within 40 minutes. (5-2) Clean the surface of the drainage holes and install the drainage hole ball valve; drill holes on the reserved grouting holes of the tunnel segments until the entire tunnel segment and the outer layer of the tunnel formed by synchronous grouting are completely drilled through; there are a total of 6 drainage holes, separated from the grouting holes by one ring; the drainage holes are set in the spacer ring to prevent the pore pressure from being too high during the grouting process, which may cause the tunnel segments to misalign or even crack in severe cases; (5-3) Open the ball valve of the grouting hole and connect the grouting equipment. Use the micro-disturbance grouting process to penetrate and reinforce the inner ring area. The grouting pressure is 0.2MPa~0.5MPa. The grouting rate is: cement grout flow rate is 12-14L / min, water glass grout flow rate is 6-8L / min, and mixed grout flow rate is 20L / min. (5-4) The grouting method is supplemented by alternating cement-water glass double-liquid grout and cement single-liquid grout: First, cement-water glass double-liquid grout is injected for 10 minutes; then, cement single-liquid grout is injected for 5 minutes; then, cement-water glass double-liquid grout is injected again for 5 minutes; finally, cement single-liquid grout is injected until the grouting is completed. (6) At the same time as grouting, open the ball valve of the drain hole parallel to the grouting hole to release water and use a total station to monitor the convergence deformation of the pipe segment in real time; if the convergence deformation of the pipe segment exceeds 2mm or the grouting pressure rises to 0.6MPa, grouting should be stopped to protect the pipe segment. (7) After construction is completed, clean up the site.

2. The method according to claim 1, wherein, The self-excited oscillating pulse grouting process parameters are as follows: grouting pressure is 8~10MPa, grouting flow rate is 160~180L / min; rotation speed is 20r / min, and rod extraction speed is 110mm / min. When reinforcing the soil, the self-excited oscillating pulse grouting process can form an effective and completely closed grouting outer ring, which has the effect of preventing the inner ring grout from spreading away from the shield tunnel segment lining.

3. The drilling and injecting integrated device for realizing the water leakage treatment method of the water-rich sand layer shield tunnel according to any one of claims 1-2, characterized in that, The device includes a grouting joint, a grouting main cylinder, and a drill bit; the grouting main cylinder is a cylindrical structure, with one end connected to the drill bit, which is welded to the end where the outlet boundary of the grouting main cylinder is located; the other end is connected to the grouting joint, which is threaded to the end where the inlet boundary of the grouting main cylinder is located. The grouting main cylinder consists of a self-excited oscillation pulse structure zone and a grouting chamber. The self-excited oscillation pulse structure zone includes a chamber, an inlet, an outlet, an upper nozzle, and a lower nozzle. The inlet is connected to the grouting joint through the inlet boundary, and the outlet is connected to the drill bit through the outlet boundary. The chamber diameter is D, the upper nozzle diameter is d1, the lower nozzle diameter is d2, the chamber length is H, and the lower nozzle cone angle is a, with specific values ​​of: D / d2=6.5~8.5, d2 / d1=1.6~2.1, H / D=0.5~0.7, and a=120°. The grouting chamber is adjacent to the outlet boundary of the self-excited oscillation pulse structure zone, and has 5 layers of grouting holes evenly distributed circumferentially on its outer surface. The grouting holes have a diameter of 2mm and a total of 100 holes, which are evenly distributed circumferentially in 5 layers on the outer surface of the grouting chamber, with a spacing of 50mm between each layer.

4. The drill-and-injection integrated device according to claim 3, wherein The grouting main cylinder has a diameter of 48mm and a length of 3.6m.

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