Multiple grouting treatment method under high water pressure and geological condition of ground fissure

Abstract

This invention discloses a method for multiple grouting treatment under high water pressure ground fissure geological conditions, relating to the field of tunnel engineering construction technology. The method includes the following steps: conducting geological surveys of the ground fissures and determining construction parameters; designing segmented and jointed tunnel structures; pre-embedding a double-layer waterstop waterproof structure at the deformation joints; performing initial grouting reinforcement using a grouting device; conducting shield tunneling and real-time deformation monitoring; and performing secondary and multiple supplementary grouting when the monitored structural deformation exceeds the warning value or micro-leakage occurs in the waterproof system; and conducting grouting effect testing and acceptance. This invention employs the above-mentioned multiple grouting treatment method under high water pressure ground fissure geological conditions, combined with segmented and jointed structures, double-layer waterstops, and inclined pipe laying, forming an integrated system of reinforcement, waterproofing, and protection, significantly improving safety and durability.

Description

Technical Field

[0001] This invention relates to the field of tunnel engineering construction technology, and in particular to a method for multiple grouting treatment under geological conditions of high water pressure and ground fissures. Background Technology

[0002] When shield tunnels pass through areas with well-developed ground fissures, the strata generally have characteristics such as broken rock mass, developed fissures, and poor integrity. Under the action of high groundwater pressure, uneven settlement of strata, cracking of tunnel structure, opening of deformation joints, leakage, and even water and sand inrush are very likely to occur.

[0003] Traditional methods for treating ground fissures often involve one-time grouting reinforcement, which has the following drawbacks: Ground fissures have the characteristics of long-term slow activity. A single grouting is difficult to meet the requirements of continuous deformation control in the later stage. After leakage occurs, it is necessary to re-drill holes and re-bury pipes, which is complex, costly and causes great secondary disturbance to the structure. The lack of a systematic treatment plan that matches the tunnel expansion joints and double-layer waterproofing system makes it difficult to guarantee the overall waterproofing and reinforcement effect; Unclear grouting procedures and unclear grouting sequence can easily lead to uneven formation reinforcement and incomplete filling of deep fissures.

[0004] Therefore, there is an urgent need to design a grouting treatment method that can be pre-embedded once, replenished multiple times, reliably connected, stably sealed, with clear procedures, and suitable for high water pressure ground fissure conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a method for multiple grouting treatment under high water pressure ground fissure geological conditions, thereby solving the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides a method for multiple grouting treatment under geological conditions of high water pressure ground fissures, comprising the following steps: S1. Conduct geological investigation of ground fissures and determine construction parameters; S2. Design the tunnel structure by segmentation and jointing; S3. Pre-embed a double-layer waterstop waterproof structure at the expansion joint; S4. Initial grouting reinforcement is carried out using a grouting device; S5. Conduct shield tunneling and real-time deformation monitoring; S6. When the structural deformation exceeds the warning value or the waterproofing system shows micro-leakage, secondary and multiple grouting injections shall be carried out. S7. Conduct grouting effect testing and acceptance.

[0007] Preferably, S1 includes: determining the direction, depth, vertical displacement, horizontal tension, and surrounding water pressure distribution of the ground fissure by combining micro-motion method and elastic wave CT, and determining the construction range and stratum reinforcement parameters of the affected section of the ground fissure.

[0008] Preferably, S2 includes: a segmented structural design with enlarged cross-section and reserved clearance for the affected section of the ground fissure, the segment length matching the deformation characteristics of the ground fissure, deformation joints set between the segments, and the width of the deformation joints set to 20-50cm according to the displacement amount of the geological survey.

[0009] Preferably, S3 includes: S31. Lay a reinforced waterproof layer on the outside of the expansion joint and install the first waterstop to form an outer closed waterproof line; S32. A U-shaped waterstop is installed inside the expansion joint, with the groove of the U-shaped waterstop facing the expansion joint side to form an inner closed waterproof line. S33. Two grouting pipes are pre-embedded on each side of the deformation joint. The grouting pipes are arranged symmetrically and inclined, with the angle between them and the horizontal direction set at 30-45°. The bottom end of the grouting pipe extends to the core layer of the ground fissure influence zone, and the top end is reserved for maintenance grouting interface and sealed.

[0010] Preferably, the grouting pipe in S32 is a corrugated grouting pipe, and the outer side of the grouting pipe is wrapped with a geotextile filter layer. The grouting pipe is equipped with a one-way grout outlet valve, and the opening pressure of the one-way grout outlet valve is 0.3-0.5MPa.

[0011] Preferably, the grouting device includes a grouting host, which is connected to one end of the grouting main pipe via a connecting pipe. The other end of the grouting main pipe is connected to the grouting pipe. A positioning bracket is provided at the connection between the grouting pipe and the grouting main pipe. A locking component is provided on the positioning bracket. The locking component is used to fix the grouting main pipe and the grouting pipe. The positioning bracket includes a lower foundation and an upper foundation. A first receiving sleeve and a second receiving sleeve are provided between the upper foundation and the lower foundation. Two connecting seats are provided between the second receiving sleeve and the first receiving sleeve, and each connecting seat is provided with a locking element. The locking component includes a lower ring and an upper ring. One end of the upper ring and the lower ring are hinged to the connecting plate. The other end of the lower ring is rotatably connected to one end of the hanging ring. The other end of the hanging ring is rotatably connected to one end of the rotating plate. The other end of the rotating plate is rotatably connected to the other end of the upper ring. A lever plate is also fixedly connected to the end of the rotating plate.

[0012] Preferably, the end of the grouting main pipe connected to the grouting pipe is provided with a conical sealing head, and the outer surface of the conical sealing head is provided with a soft sealing layer.

[0013] Preferably, S4 includes: performing layered grouting on the strata on both sides of the deformation joint and around the grouting pipe using a grouting device. The first grouting uses cement-water glass double-liquid grout, and the grouting pressure is dynamically adjusted to 0.8-1.5MPa according to the water pressure until the grout fills the ground fissures densely and the pressure is stable. The initial grouting sequence is from bottom to top. First, grout the core area of ​​the deep ground fissures, then fill the shallow ground. After each layer of grouting is completed, stabilize the pressure for 3-5 minutes, and then open the control valve of the next layer for grouting.

[0014] Preferably, S6 includes: when the vertical deformation is ≥5mm, the horizontal deformation is ≥3mm, and the monitoring data reaches the warning value, the shield tunneling is stopped immediately, and grouting is performed by using a grouting device through the reserved grouting interface. The grouting is performed by selecting ultrafine cement grout or modified epoxy resin grout according to the stratum conditions. The grouting pressure is increased by 0.2-0.5MPa compared with the first grouting until the deformation is stable and the leakage is eliminated. The modified epoxy resin slurry has a solid content of 60-70%, with added toughening agents and waterproofing agents, and the initial setting time of the slurry is controlled at 10-30 minutes.

[0015] Preferably, S7 includes: S71. Randomly drill and core samples in the treated section to test the density and compressive strength of the grout. The density is required to be ≥90% and the 28-day compressive strength of the grout is required to be ≥10MPa. S72. The overall distribution of the grouting body was detected by elastic wave CT, confirming that there were no obvious voids or cracks, and that the grouting body in the ground fissure affected area was continuous and intact. S73. Conduct a waterproofing system sealing test. Verify that there is no leakage at the deformation joint through a water pressure test. After passing the test, complete multiple grouting treatments for the high water pressure ground fissure geological conditions and proceed to the subsequent tunnel construction procedures.

[0016] Therefore, the present invention employs the above-mentioned method of multiple grouting treatment under high water pressure ground fissure geological conditions, which has the following beneficial effects: (1) In this method, a repeatable grouting pipe can be pre-embedded once and can be repeatedly grouted later, which is suitable for the long-term slow deformation characteristics of ground fissures and greatly reduces the later maintenance cost.

[0017] (2) The grouting device in this method has a positioning bracket and a locking component that can quickly fix the grouting main pipe and the pre-embedded pipe, ensuring coaxiality and stability, and preventing shaking and leakage under high water pressure.

[0018] (3) The conical structure of the grouting main pipe in this method, combined with the soft sealing layer, seals immediately upon insertion. Combined with the one-way valve, it can effectively prevent groundwater backflow and grout backflow.

[0019] (4) This method adopts layered grouting from bottom to top and segmented pressure stabilization, which can fill both deep and shallow strata densely, and the reinforcement effect is uniform and reliable.

[0020] (5) This method combines segmented joints, double-layer waterstops, and inclined pipe laying to form an integrated system of reinforcement, waterproofing, and protection, which significantly improves safety and durability.

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a flowchart of the method for multiple grouting treatment under high water pressure ground fissure geological conditions according to the present invention; Figure 2 This is a schematic diagram of the construction layout for the multiple grouting treatment method under high water pressure ground fissure geological conditions according to the present invention; Figure 3 This is a schematic diagram of the waterstop structure in the multiple grouting treatment method for high water pressure ground fissure geological conditions according to the present invention. Figure 4 This is a schematic diagram of the positioning bracket in the grouting device of the present invention; Figure 5 This is a schematic diagram of the locking element in the grouting device of the present invention; Figure 6 This is a schematic diagram of the grouting main pipe in the grouting device of the present invention; Reference numerals in the attached drawings: 1. First waterstop; 2. U-shaped waterstop; 3. Grouting pipe; 41. Lower foundation; 42. Upper foundation; 43. First receiving sleeve; 44. Second receiving sleeve; 45. Connecting seat; 5. Locking element; 51. Lower ring; 52. Upper ring; 53. Connecting plate; 54. Hanging ring; 55. Rotating plate; 56. Actuating plate; 6. Main grouting pipe; 61. Conical sealing head; 62. Soft sealing layer. Detailed Implementation

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0025] Example Please see Figures 1-6 This invention provides a method for multiple grouting treatment under high water pressure ground fissure geological conditions, including the following steps: S1. Conduct geological surveys of ground fissures and determine construction parameters. Using a combination of micro-motion method and elastic wave CT, determine the direction, depth, vertical displacement, horizontal tension, and surrounding water pressure distribution of the ground fissures, and determine the construction range and stratum reinforcement parameters of the affected area.

[0026] S2. Implement segmented and jointed tunnel structure design. For sections affected by ground fissures, adopt a segmented structure design with enlarged cross-sections and reserved clearance. The segment length matches the deformation characteristics of ground fissures, and deformation joints are set between segments. The width of the deformation joints is set to 20-50cm based on the displacement amount determined by geological survey, in order to accommodate later deformation of the strata and avoid tensile cracking and shearing damage to the tunnel structure.

[0027] S3. A double-layer waterproof structure with waterstop strips is pre-embedded at the expansion joint. This includes: S31. Lay a reinforced waterproof layer on the outside of the expansion joint and install the first waterstop 1 to form an outer closed waterproof line.

[0028] S32. A U-shaped waterstop 2 is installed inside the expansion joint, with the groove of the U-shaped waterstop 2 facing the expansion joint side, forming an inner closed waterproof line. Figure 2 and Figure 3 As shown.

[0029] S33. Two grouting pipes 3 are pre-embedded on each side of the deformation joint. The grouting pipes 3 are arranged symmetrically and inclined, with an angle of 30-45° to the horizontal direction. The bottom end of the grouting pipe 3 extends to the core layer of the ground fissure influence zone, and the top end is reserved for maintenance grouting interface and sealed. The grouting pipe 3 is a corrugated grouting pipe 3, and the outside of the grouting pipe 3 is wrapped with a geotextile filter layer. The grouting pipe 3 is equipped with a one-way grout outlet valve. The opening pressure of the one-way grout outlet valve is 0.3-0.5MPa to prevent grout backflow and groundwater backflow after grouting.

[0030] S4. Initial grouting reinforcement is carried out using a grouting device. The grouting device includes a grouting main unit, which is connected to one end of the grouting main pipe 6 via a connecting pipe. The other end of the grouting main pipe 6 is connected to the grouting pipe 3. A positioning bracket is provided at the connection between the grouting pipe 3 and the grouting main pipe 6. A locking element 5 is provided on the positioning bracket. The locking element 5 is used to fix the grouting main pipe 6 and the grouting pipe 3.

[0031] like Figure 4 As shown, the positioning bracket includes a lower base 41 and an upper base 42. A first receiving sleeve 43 and a second receiving sleeve 44 are provided between the upper base 42 and the lower base 41. Two connecting seats 45 are provided between the second receiving sleeve 44 and the first receiving sleeve 43. Each connecting seat 45 is provided with a locking element 5.

[0032] like Figure 5 As shown, the locking component 5 includes a lower ring 51 and an upper ring 52. One end of both the upper ring 51 and the lower ring 52 is hinged to the connecting plate 53. The other end of the lower ring 51 is rotatably connected to one end of the hanging ring 54. The other end of the hanging ring 54 is rotatably connected to one end of the rotating plate 55, and the other end of the rotating plate 55 is rotatably connected to the other end of the upper ring 52. A lever plate 56 is also fixedly connected to the end of the rotating plate 55, which allows for quick locking and unlocking.

[0033] like Figure 6 As shown, a conical sealing head 61 is provided at the end where the grouting main pipe 6 connects to the grouting pipe 3. A soft sealing layer 62 is provided on the outer surface of the conical sealing head 61. After the conical sealing head 61 is inserted, it fits tightly against the inner wall of the grouting pipe 3 to achieve high water pressure sealing.

[0034] The steps for using the grouting device are as follows: Remove the sealing cap at the top of the pre-embedded grouting pipe 3, clean the debris from the inner wall of the pipe opening, and ensure that the mating surface is clean.

[0035] Align the conical sealing head 61 at the end of the grouting main pipe 6 with the opening of the pre-embedded grouting pipe 3, and slowly insert it along the axial direction until the conical sealing head 61 is fully inserted into the pre-embedded pipe and forms a preliminary seal.

[0036] The positioning bracket is placed between the pre-embedded grouting pipe 3 and the main grouting pipe 6, so that the first receiving sleeve 43 wraps around the outer wall of the pre-embedded grouting pipe 3 and the second receiving sleeve 44 wraps around the outer wall of the main grouting pipe 6.

[0037] The lower ring 51 and the upper ring 52 are respectively fastened to the outer walls of the pre-embedded grouting pipe 3 and the grouting main pipe 6. The hanging ring 54 is rotated to fasten the rotating plate 55. The lever plate 56 is pulled down to make the locking part 5 hold the pipe body tightly, so as to achieve the same angle, coaxiality and no shaking fixation of the pre-embedded grouting pipe 3 and the grouting main pipe 6.

[0038] For the sealing check, start the grouting host for a small pressure test run, observe that there is no leakage or backflow at the joints, and after confirming that the seal is reliable, proceed with the formal grouting.

[0039] After grouting is completed and the grouting is finished and the pressure is released, pull up the lever plate 56 to loosen the hanging ring 54, open the upper ring body 52, remove the positioning bracket, and smoothly pull out the grouting main pipe 6 along the axial direction. Reseal the interface of the pre-embedded grouting pipe 3.

[0040] The aforementioned grouting device was used to perform layered grouting on the strata on both sides of the deformation joint and around the grouting pipe 3. The first grouting used cement-water glass dual-liquid grout, and the grouting pressure was dynamically adjusted to 0.8-1.5 MPa according to the water pressure until the grout filled the ground fissures densely and the pressure stabilized. The layered grouting sequence for the first grouting was from bottom to top, first grouting the core area of ​​the ground fissures in the deep strata, and then filling the shallow strata. After each layer of grouting was completed, the pressure was stabilized for 3-5 minutes before the control valve of the next layer was opened for grouting.

[0041] S5. Conduct shield tunneling and real-time deformation monitoring. Displacement sensors and water pressure sensors are installed inside the tunnel structure to continuously monitor the tunnel structure settlement, horizontal displacement, expansion joint opening and closing, and surrounding water pressure 24 hours a day, record data in real time, and make early warning judgments.

[0042] S6. When the monitored structural deformation exceeds the warning value or micro-leakage occurs in the waterproofing system, secondary and multiple grouting injections shall be performed. When the vertical deformation is ≥5mm, the horizontal deformation is ≥3mm, and the monitoring data reaches the warning value, the tunnel boring machine shall be stopped immediately, and grouting shall be performed using a grouting device through the reserved grouting interface. The grouting for the supplementary injection shall be based on the stratum conditions, using ultrafine cement grout or modified epoxy resin grout. The grouting pressure shall be increased by 0.2-0.5MPa compared to the first grouting, until the deformation stabilizes and the leakage is eliminated. Ultrafine cement grout shall be used when the stratum porosity is large; modified epoxy resin grout shall be used when there are micro-cracks and high seepage prevention requirements. Its solid content shall be 60-70%, with the addition of toughening agent and waterproofing agent, and the initial setting time shall be controlled at 10-30min. The grouting pressure for the supplementary injection shall be increased by 0.2-0.5MPa compared to the first grouting, and grouting shall be completed after the structural deformation has subsided, the leakage has been eliminated, and the pressure has stabilized.

[0043] S7. Conduct grouting effect testing and acceptance. This includes: S71. Randomly drill and core samples in the treated section to test the density and compressive strength of the grout. The density is required to be ≥90% and the 28-day compressive strength of the grout is required to be ≥10MPa. S72. The overall distribution of the grouting body was detected by elastic wave CT, confirming that there were no obvious voids or cracks, and that the grouting body in the ground fissure affected area was continuous and intact. S73. Conduct a waterproofing system sealing test. Verify that there is no leakage at the deformation joint through a water pressure test. After passing the test, complete multiple grouting treatments for the high water pressure ground fissure geological conditions and proceed to the subsequent tunnel construction procedures.

[0044] Example 1 A shield tunnel for urban rail transit passes under an active ground fissure section. The strata are mainly composed of silty clay and silt, with fractured rock mass. The vertical displacement of the ground fissure is about 0.7m, the horizontal tension is about 0.4m, and the groundwater pressure is 0.4–0.6MPa, which is a typical high water pressure ground fissure working condition.

[0045] The process is performed using the method described in this invention: Through micro-motion method and elastic wave CT investigation, the length of the ground fissure affected area was determined to be 20m, and one deformation joint with a width of 30cm was designed.

[0046] The expansion joint is waterproofed with a double-layer waterstop: an outer reinforced waterproof layer and a first waterstop 1 are installed, and an inner U-shaped waterstop 2 is installed.

[0047] Two corrugated reusable grouting pipes are pre-embedded on each side of the expansion joint, for a total of four pipes, with a diameter of [missing information]. 48mm, with an angle of 35° to the horizontal direction, buried 8m into the core layer of the ground fissure, with the pipe opening extending 15cm out of the inner wall of the structure and sealed.

[0048] Grouting pipe 3 is equipped with a one-way grout outlet valve with an opening pressure of 0.4MPa, and the outer wall is wrapped with a geotextile filter layer.

[0049] The initial grouting used a cement-water glass two-component grout with a water-cement ratio of 1:1, a cement to water glass volume ratio of 2:1, and a grouting pressure of 1.0 MPa.

[0050] The grouting sequence is carried out in layers from bottom to top. The deep 6-8m section is grouted first, and the pressure is stabilized for 4 minutes. Then the 3-6m section is grouted, and finally the 0-3m section is grouted.

[0051] During the tunnel boring machine's excavation, a vertical deformation of 6mm was detected in the structure, triggering an early warning.

[0052] The same pre-embedded grouting pipe 3 was used for supplementary grouting. Modified epoxy resin grout with a solid content of 65% was selected, with an initial setting time of 20 minutes and a grouting pressure of 1.3 MPa.

[0053] After the injection, the deformation returned to 2.5mm, and the leakage was completely eliminated.

[0054] Test results: Grout density 93%; 28-day compressive strength 12.3 MPa; Elastic wave CT showed that the strata were intact and without voids; No leakage was observed during the expansion joint water pressure test at 0.8 MPa for 30 minutes.

[0055] The project implementation shows that this method is convenient to construct, has reliable connection, and good sealing effect. It can achieve one-time pre-embedding and multiple injections, and can control the deformation and leakage of ground fissures in the long term, demonstrating significant engineering practicality.

[0056] Therefore, the present invention adopts the above-mentioned method of multiple grouting treatment under the geological conditions of high water pressure ground fissures. It adopts layered grouting from bottom to top and segmented pressure stabilization, which can fill both deep and shallow strata densely and achieve uniform and reliable reinforcement effect. Combined with segmented joints, double-layer waterstops and inclined pipe laying, it forms an integrated system of reinforcement, waterproofing and protection, which significantly improves safety and durability.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for multiple grouting treatment under high water pressure ground fissure geological conditions, characterized in that, Includes the following steps: S1. Conduct geological investigation of ground fissures and determine construction parameters; S2. Design the tunnel structure by segmentation and jointing; S3. Pre-embed a double-layer waterstop waterproof structure at the expansion joint; S4. Initial grouting reinforcement is carried out using a grouting device; S5. Conduct shield tunneling and real-time deformation monitoring; S6. When the structural deformation exceeds the warning value or the waterproofing system shows micro-leakage, secondary and multiple grouting injections shall be carried out. S7. Conduct grouting effect testing and acceptance.

2. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 1, characterized in that, The S1 includes: using a combination of micro-motion method and elastic wave CT to detect the direction, burial depth, vertical displacement, horizontal tension and surrounding water pressure distribution of the ground fissure, and to determine the construction range and stratum reinforcement parameters of the affected section of the ground fissure.

3. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 2, characterized in that, The S2 includes: a segmented structural design with enlarged cross-section and reserved clearance for the affected section of the ground fissure, the segment length matching the deformation characteristics of the ground fissure, deformation joints set between the segments, and the width of the deformation joints set to 20-50cm according to the displacement amount of the geological survey.

4. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 3, characterized in that, S3 includes: S31. Lay a reinforced waterproof layer on the outside of the expansion joint and install the first waterstop to form an outer closed waterproof line; S32. A U-shaped waterstop is installed inside the expansion joint, with the groove of the U-shaped waterstop facing the expansion joint side to form an inner closed waterproof line. S33. Two grouting pipes are pre-embedded on each side of the deformation joint. The grouting pipes are arranged symmetrically and inclined, with the angle between them and the horizontal direction set at 30-45°. The bottom end of the grouting pipe extends to the core layer of the ground fissure influence zone, and the top end is reserved for maintenance grouting interface and sealed.

5. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 4, characterized in that: The grouting pipe in S32 is a corrugated grouting pipe, and the outer side of the grouting pipe is wrapped with a geotextile filter layer. The grouting pipe is equipped with a one-way grout outlet valve, and the opening pressure of the one-way grout outlet valve is 0.3-0.5MPa.

6. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 5, characterized in that: The grouting device includes a grouting host, which is connected to one end of the grouting main pipe via a connecting pipe. The other end of the grouting main pipe is connected to the grouting pipe. A positioning bracket is provided at the connection between the grouting pipe and the grouting main pipe. A locking component is provided on the positioning bracket. The locking component is used to fix the grouting main pipe and the grouting pipe. The positioning bracket includes a lower foundation and an upper foundation. A first receiving sleeve and a second receiving sleeve are provided between the upper foundation and the lower foundation. Two connecting seats are provided between the second receiving sleeve and the first receiving sleeve, and each connecting seat is provided with a locking element. The locking component includes a lower ring and an upper ring. One end of the upper ring and the lower ring are hinged to the connecting plate. The other end of the lower ring is rotatably connected to one end of the hanging ring. The other end of the hanging ring is rotatably connected to one end of the rotating plate. The other end of the rotating plate is rotatably connected to the other end of the upper ring. A lever plate is also fixedly connected to the end of the rotating plate.

7. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 6, characterized in that, The end of the grouting main pipe connected to the grouting pipe is provided with a conical sealing head, and the outer surface of the conical sealing head is provided with a soft sealing layer.

8. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 7, characterized in that, The S4 includes: layered grouting of the strata on both sides of the deformation joint and around the grouting pipe through a grouting device. The first grouting uses cement-water glass double liquid grout, and the grouting pressure is dynamically adjusted to 0.8-1.5MPa according to the water pressure until the grout fills the ground fissures densely and the pressure is stable. The initial grouting sequence is from bottom to top. First, grout the core area of ​​the deep ground fissures, then fill the shallow ground. After each layer of grouting is completed, stabilize the pressure for 3-5 minutes, and then open the control valve of the next layer for grouting.

9. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 8, characterized in that, S6 includes: when the vertical deformation is ≥5mm, the horizontal deformation is ≥3mm, and the monitoring data reaches the warning value, the shield tunneling is stopped immediately, and grouting is carried out by using a grouting device through the reserved grouting interface. The grouting is selected according to the stratum conditions, using ultrafine cement grout or modified epoxy resin grout. The grouting pressure is increased by 0.2-0.5MPa compared with the first grouting until the deformation is stable and the leakage is eliminated. The modified epoxy resin slurry has a solid content of 60-70%, with added toughening agents and waterproofing agents, and the initial setting time of the slurry is controlled at 10-30 minutes.

10. The method for multiple grouting treatment under high water pressure ground fissure geological conditions according to claim 9, characterized in that, S7 includes: S71. Randomly drill and core samples in the treated section to test the density and compressive strength of the grout. The density is required to be ≥90% and the 28-day compressive strength of the grout is required to be ≥10MPa. S72. The overall distribution of the grouting body was detected by elastic wave CT, confirming that there were no obvious voids or cracks, and that the grouting body in the ground fissure affected area was continuous and intact. S73. Conduct a waterproofing system sealing test. Verify that there is no leakage at the deformation joint through a water pressure test. After passing the test, complete multiple grouting treatments for the high water pressure ground fissure geological conditions and proceed to the subsequent tunnel construction procedures.

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