Double-liquid-bag grouting anchor pipe device capable of expanding shell and temporarily plugging and construction method

Abstract

The invention relates to the technical field of grouting anchoring, and particularly discloses a double-liquid-bag grouting anchor pipe device capable of expanding and temporarily plugging and a construction method. The construction method comprises the steps that S1, a hole is formed, and a double-liquid-bag grouting anchor pipe is placed in the hole; s2, filling fluid to enable the first capsule body and the second capsule body to expand; s3, high-pressure grouting is conducted; and S4, solidifying the slurry and fixing the tail tray. The double-liquid-bag grouting anchor pipe device comprises a double-liquid-bag hollow grouting anchor pipe, a first bag body, a second bag body, a metal shell protection strip, a slurry outlet, a front end side bag body liquid filling channel, a tail end side bag body liquid filling channel, a pressure-resistant ball valve and the like. The scheme can be suitable for different geological environments, operation is easy and convenient, the construction efficiency and the engineering quality are high, the grouting pressure can be effectively improved through the high-pressure grouting technology, durability and stability are enhanced, stress balance in the grouting process can be ensured through the double-bag-body structure, displacement of the anchor pipe is avoided, the overall anchoring effect is optimized, and the construction period is shortened. And the method can be suitable for multiple scenes including tunnel surrounding rock reinforcement and water-rich soft foundation treatment, and is high in adaptability.

Description

Technical Field

[0001] The present invention relates to the technical field of grouting and anchoring, and specifically provides a double-fluid-bag grouting anchor pipe device with expandable shell and temporary plugging and a construction method therefor. Background Art

[0002] The grouting anchor pipe device is a device used for geotechnical engineering reinforcement and waterproofing. Its main function is to inject slurry into the anchor pipe through the grouting pipe, thereby enhancing the stability of the foundation or structure. The grouting anchor pipe device is widely used in tunnel engineering, slope support, foundation pit support and other fields. For example, in tunnel engineering, the grouting anchor pipe can be used for advanced support and permanent system support to ensure the safety and stability of tunnel construction. The working principle of the grouting anchor pipe device is as follows: The cement slurry is transported to the locking foot anchor pipe through the conveying pipe by the grouting machine. The block in the sealing mechanism cooperates with the movable pipe, and the gap between the grouting device and the locking foot anchor pipe is sealed by squeezing the rubber ring. The slurry is ejected through the grouting holes of the grouting pipe under the action of pressure, filling the gap between the anchor pipe and the surrounding rock and soil, and forming a solid support structure after coagulation.

[0003] The main limitations of the hollow grouting anchor pipe of the traditional grouting anchor pipe device lie in poor grouting and anchoring effect and insufficient bearing capacity, specifically manifested as follows: 1) Lower grouting pressure will cause the slurry to not fully penetrate into the surrounding rock or foundation, resulting in uneven grouting, inability to form an effective anchoring network, insufficient anchoring strength, and poor performance in resisting external loads; 2) In terms of bearing capacity, the design of the traditional hollow grouting anchor pipe cannot meet the implementation conditions of high-pressure grouting, fails to improve the diffusion range and anchoring effect of the slurry, resulting in lower overall bearing capacity and inability to meet the requirements in complex geological environments; 3) Lack of balanced distribution of forces during the grouting process, which easily causes the anchor pipe to shift or fall off during high-pressure grouting, further affecting the overall stability and long-term bearing capacity.

[0004] Therefore, it is an urgent problem to be solved at present to propose a grouting anchor pipe device and a construction method with high anchoring strength and bearing performance, and strong stability and adaptability under complex stratum conditions. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a double-fluid-bag grouting anchor pipe device with expandable shell and temporary plugging and a construction method therefor. Through the expansion of the bladder structure and high-pressure grouting technology, combined with the metal shell protection strip structure, the anchoring ability, force balance and engineering applicability of the anchor rod can be comprehensively improved, and the mechanical properties of the surrounding rock or soft foundation can be effectively improved.

[0006] A double-fluid-bag grouting construction method provided by the present invention includes the following steps:

[0007] S1. Open a hole and place the double-fluid-bag grouting anchor pipe;

[0008] S11. Conduct drilling layout, and control the position and specifications of the drill holes according to the working conditions;

[0009] S12. Install the double-fluid bag grouting anchor pipe;

[0010] S2. Fill the fluid to expand the first and second bags;

[0011] S21. Select the fluid and inject it;

[0012] S22. The first and second bags expand;

[0013] S23. The metal shell protection strip unfolds;

[0014] S3. High-pressure grouting;

[0015] S31. Conduct plugging control and adjust the grouting pressure;

[0016] S32. Inject and diffuse the grout;

[0017] S33. Conduct splitting-compaction reinforcement;

[0018] S4. The grout solidifies and the tail tray is fixed;

[0019] S41. Conduct solidification monitoring and strength evaluation;

[0020] S42. Fix the tail tray and conduct long-term anchoring;

[0021] S43. Conduct quality inspection and bearing capacity evaluation.

[0022] Furthermore, when anchoring the tunnel surrounding rock,

[0023] In step S11, the position needs to be determined according to the characteristics of the surrounding rock and the reinforcement requirements, and the drill holes are arranged along the side wall or the arch; the drill hole angle is adjusted according to the stability of the surrounding rock, and the drilling is carried out in the direction of obliquely downward, horizontally or obliquely upward; the drill hole diameter is 1.2 to 1.5 times the diameter of the double-fluid bag grouting anchor pipe, and after the drill hole is completed, the debris, loose rock and accumulated water in the drill hole are cleaned;

[0024] In step S12, the double-fluid bag grouting anchor pipe is inserted into the drill hole so that the first and second bags are located in the target anchoring area; during the insertion process, ensure that the double-fluid bag grouting anchor pipe is inserted axially in the center position and the tail tray is closely attached to the hole mouth.

[0025] Furthermore, in step S21, inert gas, water or cement slurry is injected into the bag through the infusion pipe; if the tunnel surrounding rock is water-rich surrounding rock, cement slurry is selected; in step S22, after the fluid enters the first and second bags, the first and second bags gradually expand and closely fit the hole wall; in step S23, when the first and second bags expand, the metal shell protection strip opens synchronously to form an umbrella-shaped barbed structure.

[0026] Further, in step S31, a hierarchical pressure boosting mode is adopted to gradually increase the grouting pressure; in step S32, during the high-pressure grouting process, the grouting pressure is above 3 MPa; if the tunnel surrounding rock is water-rich fine sand surrounding rock or Yunnan central red bed surrounding rock, the rheological properties of the grout need to be adjusted; in step S33, the high-pressure grout is released along the grouting holes to make the grout diffuse along the surrounding rock fissures to increase the anchoring range.

[0027] Further, when dealing with soft foundations,

[0028] In step S11, a vertical downward drilling method is adopted to drill holes for the overall reinforcement of the foundation; an inclined downward drilling method is adopted for the slope stability reinforcement; the drilling diameter is 1.2 to 1.3 times the diameter of the double-fluid bag grouting anchor pipe;

[0029] In step S12, after the drilling is completed, loose sediments are removed, and the double-fluid bag grouting anchor pipe is inserted so that the first bag and the second bag are in the target reinforcement area; during the installation of the double-fluid bag grouting anchor pipe, ensure that the double-fluid bag grouting anchor pipe is inserted vertically or at the designed angle, and make the tail tray close to the ground surface.

[0030] Further, in step S21, gas, water or cement slurry is injected into the bags through the infusion pipe to make the first bag and the second bag expand evenly and closely fit the hole wall; if the soft foundation is sandy soil, cement slurry is used; in step S22, after the first bag and the second bag expand, the pores are filled to form a local dense area; for flowing plastic clay or soft foundation with high water content, the expansion pressure needs to be adjusted to prevent soil disturbance; in step S23, after the first bag and the second bag expand, the metal shell protection strips open synchronously to form an umbrella-shaped barbed structure.

[0031] Further, in step S31, after the first bag and the second bag are fully expanded to form a seal, the grouting pressure is 1.5 - 2.5 MPa.

[0032] Further, in step S41, the curing process is monitored after the slurry is injected to ensure that the grouting material reaches the design strength within the specified time; if the slurry is a single-fluid slurry of sulfoaluminate cement, the initial setting time is 35 min to 45 min; if the slurry is a cement-sodium silicate material, the initial setting time is 40 s; in step S42, after the slurry is completely solidified, the tail tray is used to fix the anchor pipe.

[0033] A double - liquid - sac grouting anchor pipe device with expandable shells and temporary plugging, which performs grouting operations using the above - mentioned grouting construction method, includes a double - liquid - sac hollow grouting anchor pipe and sac one and sac two arranged on the double - liquid - sac hollow grouting anchor pipe. Sac one is arranged near the front end of the anchor pipe, and sac two is arranged near the tail end of the anchor pipe; both sac one and sac two are provided with metal shell protection strips, and the tail ends of the metal shell protection strips include piercing strips; a plurality of slurry outlets located on the double - liquid - sac hollow grouting anchor pipe are evenly opened between sac one and sac two; on the outer wall of the double - liquid - sac hollow grouting anchor pipe, there are a front - end side sac liquid - filling channel communicating with sac one and a tail - end side sac liquid - filling channel communicating with sac two.

[0034] Furthermore, the front ends of sac one, sac two, the slurry outlets, and the double - liquid - sac hollow grouting anchor pipe are all located within the pre - drilled hole boundary of the anchoring medium. The tail - end boundary of the pre - drilled hole boundary is close to the tail end of the anchor pipe; both the front - end side sac liquid - filling channel and the tail - end side sac liquid - filling channel extend to the outside of the tail - end boundary of the pre - drilled hole boundary; a pressure - resistant ball valve for controlling the on - off of the fluid in the front - end side sac liquid - filling channel and the tail - end side sac liquid - filling channel is provided at the tail end of the anchor pipe.

[0035] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0036] 1. In the double - liquid - sac grouting anchor pipe device of the present invention, an expansion sac structure and a metal shell protection strip structure are arranged before and after the grouting hole of the hollow grouting anchor. By filling with fluid, the sac expands, and the metal shell protection strip expands in an umbrella - like shape to form a barbed structure. Through the mechanical structure and high - pressure grouting anchoring, the anchoring and bearing performance of the hollow grouting anchor is optimized, which can improve its stability and adaptability under complex stratum conditions, and can be widely used for the reinforcement of tunnel soft - rock surrounding rock and the treatment of water - rich soft foundation to meet different engineering requirements.

[0037] 2. The present invention can achieve high - pressure split grouting, improve the slurry diffusion range and anchoring strength. The design of the double - sac structure ensures that the acting forces of the high - pressure slurry cancel each other out, avoiding the displacement or falling off of the anchor pipe due to unbalanced thrust during high - pressure grouting, thereby optimizing the stress structure and improving the overall anchoring stability.

[0038] 3. In the present invention, the metal shell protection strip is located outside the sac, similar to an umbrella - like structure, with the opening facing the tail of the anchor pipe. When the sac expands, it opens to form a barbed structure, effectively improving the anti - pull - out ability of the anchor. This protection strip can not only enhance the anchoring effect but also prevent the sac from being scratched by rocks or damaged by external forces during construction, improving the durability of the system.

[0039] 4. Compared with the traditional low-pressure or non-pressure filling grouting method, the present invention can greatly increase the grouting pressure, achieve a deeper splitting grouting effect, effectively improve the mechanical properties of surrounding rocks or soft foundations. This device has a wide adaptability, can be applied to different geological environments, and is easy to operate. During the construction process, only an appropriate fluid needs to be filled to achieve the expansion of the capsule and complete the anchoring, greatly improving the construction efficiency and engineering quality, and providing an efficient and reliable solution for tunnel surrounding rock reinforcement and treatment of water-rich soft foundations. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic structural diagram of the double-fluid capsule grouting anchor pipe device provided by an embodiment of the present invention (capsule one and capsule two are in a contracted state);

[0041] Figure 2 is a schematic structural diagram of the double-fluid capsule grouting anchor pipe device provided by an embodiment of the present invention (capsule one and capsule two are in an expanded state);

[0042] Figure 3 is a schematic diagram of the effect after high-pressure splitting grouting provided by an embodiment of the present invention;

[0043] Figure 4 is a schematic structural diagram of the tail end of the double-fluid capsule grouting anchor pipe device provided by an embodiment of the present invention.

[0044] The reference numerals therein include: front end of the anchor pipe 1, capsule one 2, capsule two 3, metal shell protection strip 4, piercing strip 5, double-fluid capsule hollow grouting anchor pipe 6, slurry outlet 7, boundary of the pre-drilled hole 8, boundary of the tail end 9, tail end of the anchor pipe 10, liquid filling channel for the tail end side capsule 11, liquid filling channel for the front end side capsule 12, pressure-resistant ball valve 13, splitting slurry vein 14, anchoring slurry 15. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following further describes the present invention in detail with reference to the accompanying Figures 1-4 drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention.

[0046] Embodiment 1

[0047] A double-fluid capsule grouting construction method with expandable shell and temporary plugging. When anchoring the tunnel surrounding rock, it includes the following steps:

[0048] S1. Open a hole and place the double-fluid capsule grouting anchor pipe.

[0049] S11. Drilling layout is carried out, and the position and specifications of the drilling are controlled according to the working conditions. In step S11 for tunnel surrounding rock reinforcement, the position needs to be determined based on the characteristics of the surrounding rock and the reinforcement requirements. The drilling is arranged along the side wall or the arch; the drilling angle is adjusted according to the stability of the surrounding rock, and the drilling is carried out in the direction of obliquely downward, horizontal or obliquely upward to optimize the anchoring effect.

[0050] The diameter of the drilling hole should be slightly larger than the diameter of the double-fluid bag grouting anchor pipe. Specifically, the diameter of the drilling hole is 1.2 to 1.5 times the diameter of the double-fluid bag grouting anchor pipe for subsequent grouting operations. After the drilling is completed, the debris, loose rock and accumulated water in the drilling hole need to be thoroughly cleaned to ensure the integrity of the hole wall and reduce the risk of slurry leakage.

[0051] S12. Install the double-fluid bag grouting anchor pipe. In step S12, slowly insert the double-fluid bag grouting anchor pipe into the drilling hole so that the capsule one 2 and the capsule two 3 are located in the target anchoring area. During the insertion process, ensure that the double-fluid bag grouting anchor pipe is inserted in the axial center position and the tail tray is closely attached to the hole mouth to provide a stable support for subsequent fixation.

[0052] S2. Inject fluid to expand the capsule one 2 and the capsule two 3. Figure 1 Figure showing the capsule one 2 and the capsule two 3 in the contracted state. Figure 2 Figure showing the capsule one 2 and the capsule two 3 in the expanded state.

[0053] S21. Select the fluid and inject the fluid. In step S21, inject inert gas, water or cement slurry into the capsule through the infusion tube to ensure that the capsule can be fully expanded; the selection of the fluid needs to be combined with the surrounding rock environment. If the tunnel surrounding rock is water-rich surrounding rock, then select cement slurry to improve the anchoring effect.

[0054] S22. The capsule one 2 and the capsule two 3 expand. In step S22, after the fluid enters the capsule one 2 and the capsule two 3, the capsule one 2 and the capsule two 3 gradually expand and closely fit the hole wall, forming a stable support in the complex surrounding rock environment to prevent the anchor pipe from shifting or loosening.

[0055] S23. The metal shell protection strip 4 unfolds. In step S23, when the capsule expands, the metal shell protection strip 4 opens synchronously to form an umbrella-shaped barbed structure to enhance the anchoring force. At the same time, this structure can effectively prevent the anchor pipe from shifting due to the fragmentation of the surrounding rock and improve the overall stability.

[0056] S3. High-pressure grouting.

[0057] S31. Carry out plugging control and adjust the grouting pressure. In step S31, it is necessary to ensure that the capsule structure is fully expanded to form an effective plug to prevent the slurry from flowing back along the hole mouth during the injection process. At the same time, a step-by-step pressurization mode is adopted to gradually increase the grouting pressure.

[0058] S32. Slurry injection and diffusion. During the high-pressure grouting process in step S32, the grouting pressure is above 3 MPa to allow the slurry to penetrate into the surrounding rock fissures and form a stable grout vein. If the tunnel surrounding rock is water-rich fine sand or red bed in central Yunnan, the rheological properties of the slurry need to be appropriately adjusted to optimize the consolidation effect.

[0059] S33. Carry out splitting-compaction reinforcement. In step S33, release the high-pressure slurry along the grouting holes to form a splitting-compaction effect, allowing the slurry to spread along the surrounding rock fissures to increase the anchorage range and improve the overall stability of the surrounding rock. The splitting grout vein 14 is as Figure 3 shown in the figure.

[0060] S4. Slurry solidification and fixing of the tail tray. After the slurry is injected, continuously monitor the solidification state to ensure that the slurry fully fills the surrounding rock fissures and remains stable during the solidification process.

[0061] S41. Carry out solidification monitoring and strength evaluation. After the slurry solidifies, use the tail tray structure to further fix the anchor pipe to prevent loosening or failure under the action of construction loads and ensure long-term stability.

[0062] S42. Carry out fixing of the tail tray and long-term anchorage. After completion of solidification and fixing, conduct quality inspection on the anchorage area to ensure that the anchor bolt has sufficient bearing capacity and pullout resistance, thus forming a high-strength and durable surrounding rock reinforcement system.

[0063] S43. Determine the grouting reinforcement range based on the borehole exploration data, and conduct quality inspection and bearing capacity evaluation.

[0064] In actual use, the tail tray structure is installed at the tail end 10 of the anchor pipe, which can restrain the expanded shapes of the first capsule 2 and the second capsule 3, prevent abnormal deformation of the first capsule 2 and the second capsule 3, and at the same time further enhance the anchorage effect to ensure that the anchor bolt still has a stable bearing capacity under long-term loads.

[0065] A double-fluid capsule grouting anchor pipe device with expandable shell and temporary plugging uses the above grouting construction method for grouting operation, as Figures 1 to 4 shown in the figure, including a double-fluid capsule hollow grouting anchor pipe 6. The double-fluid capsule hollow grouting anchor pipe 6 is provided with a first capsule 2 and a second capsule 3. The first capsule 2 is arranged near the front end 1 of the anchor pipe, and the second capsule 3 is arranged near the tail end 10 of the anchor pipe. Both the first capsule 2 and the second capsule 3 are provided with metal shell protection strips 4. The tail end of the metal shell protection strip 4 includes a piercing strip 5. A plurality of slurry outlets 7 located on the double-fluid capsule hollow grouting anchor pipe 6 are evenly arranged between the first capsule 2 and the second capsule 3. On the outer wall of the double-fluid capsule hollow grouting anchor pipe 6, there are provided a front-end side capsule liquid filling channel 12 communicating with the first capsule 2 and a tail-end side capsule liquid filling channel 11 communicating with the second capsule 3.

[0066] The front ends of the first bladder 2, the second bladder 3, the slurry outlet 7, and the double-fluid bladder hollow grouting anchor pipe 6 are all located within the boundary 8 of the pre-drilled hole in the anchoring medium. The tail end boundary 9 of the pre-drilled hole boundary 8 is close to the tail end 10 of the anchor pipe. When the first bladder 2 and the second bladder 3 are in Figure 1 the contracted state shown in, the metal shell protection strip 4 contracts within the pre-drilled hole boundary 8. When the first bladder 2 and the second bladder 3 are in Figure 2 the expanded state shown in, the first bladder 2 and the second bladder 3 expand. At this time, the metal shell protection strip 4 opens synchronously. The tail of the metal shell protection strip 4 opens to the outside of the pre-drilled hole boundary 8. The metal shell protection strip 4 forms an umbrella-like structure. After the metal shell protection strip 4 is opened, the opening faces the tail end 10 of the anchor pipe. The piercing strips 5 at the tail of the metal shell protection strip 4 form barbed structures and pierce into the part of the anchoring medium, that is, within the pre-drilled hole boundary 8, and penetrate deep into the surrounding rock, which can improve the pull-out resistance of the bolt and the overall anchoring effect.

[0067] The front-end side bladder liquid filling channel 12 and the tail-end side bladder liquid filling channel 11 both extend to the outside of the tail end boundary 9 of the pre-drilled hole boundary 8; a pressure-resistant ball valve 13 for controlling the on-off of the fluid in the front-end side bladder liquid filling channel 12 and the tail-end side bladder liquid filling channel 11 is provided at the tail end 10 of the anchor pipe.

[0068] Embodiment 2

[0069] The difference between this embodiment and Embodiment 1 is that this embodiment is used for the working condition of soft foundation treatment. When performing soft foundation treatment:

[0070] S1. Open a hole and place the double-fluid bladder grouting anchor pipe.

[0071] S11. Conduct drilling layout and control the position and specifications of the drilling according to the working conditions. In step S11, the vertical downward drilling method is used for the overall reinforcement of the foundation; the inclined downward drilling method is used for the slope stability reinforcement; the drilling depth is set according to the foundation bearing requirements, usually shallower than the embedding depth of the tunnel surrounding rock reinforcement to improve the construction efficiency. The drilling diameter is 1.2 to 1.3 times the diameter of the double-fluid bladder grouting anchor pipe to reduce pores and improve the grouting density. For loose sandy soil or silt foundation, special control of the drilling diameter is required to avoid hole wall collapse or slurry leakage.

[0072] S12. Install the double-fluid bladder grouting anchor pipe. In step S12, after the drilling is completed, remove the loose sediment and slowly insert the double-fluid bladder grouting anchor pipe so that the first bladder 2 and the second bladder 3 are in the target reinforcement area; during the installation of the double-fluid bladder grouting anchor pipe, ensure that the double-fluid bladder grouting anchor pipe is inserted vertically or at the designed angle, and make the tail tray close to the ground surface to ensure the anchoring stability.

[0073] S2. Fill the fluid to expand the first bladder 2 and the second bladder 3.

[0074] S21. Select a fluid and inject it. In step S21, gas, water, or cement slurry is injected into the capsule through an infusion tube to uniformly expand capsule 2 and capsule 3, making them closely fit the hole wall. If the soft foundation flow is sandy soil, cement slurry is used to reduce leakage.

[0075] S22. Capsule 2 and capsule 3 expand. In step S22, after capsule 2 and capsule 3 expand, the pores are filled to form a locally dense area. For plastic clay or soft foundation with high water content, the expansion pressure needs to be appropriately adjusted to prevent soil disturbance.

[0076] S23. The metal shell protection strip 4 unfolds. In step S23, after capsule 2 and capsule 3 expand, the metal shell protection strip 4 synchronously opens to form an umbrella-shaped barbed structure, increasing the uplift resistance of the anchor pipe and providing additional protection for the capsule to prevent damage during construction.

[0077] S3. High-pressure grouting.

[0078] S31. Conduct plugging control and adjust the grouting pressure. In step S31, after capsule 2 and capsule 3 are fully expanded, an effective plugging is formed to prevent the slurry from diffusing or overflowing along the pores. Compared with the tunnel surrounding rock reinforcement in Embodiment 1, the grouting pressure for the soft foundation is appropriately reduced, and the grouting pressure is 1.5 - 2.5 MPa to prevent foundation instability.

[0079] S32. Slurry injection and diffusion.

[0080] S33. Carry out splitting-compaction reinforcement. After the slurry is injected along the grouting hole, it diffuses inside the soil and forms a splitting-compaction effect under appropriate pressure. This process can effectively fill the foundation pores, reduce soil compressibility, and improve bearing capacity. For sandy soil, a slurry with higher viscosity can be used to reduce leakage; for cohesive soil, chemical grouting materials can be combined to improve the consolidation effect and ensure the uniform stability of the foundation after reinforcement.

[0081] S4. Slurry solidification and fixing of the tail tray.

[0082] S41. Conduct curing monitoring and strength evaluation. In step S41, the curing process is monitored after the slurry is injected to ensure that the grouting material reaches the design strength within the specified time. For different foundation types, the curing time may vary. If the slurry is a single-component sulfoaluminate cement slurry, the initial setting time is 35 min to 45 min; if the slurry is a cement-sodium silicate material (water-cement ratio 1:1, volume ratio 3:1), the initial setting time is 40 s.

[0083] S42. Fix the tail tray and achieve long-term anchoring. In step S42, after the slurry is completely solidified, the tail tray is used to fix the anchor pipe, enhancing the overall anchoring force and preventing displacement or loosening caused by the influence of long-term loads.

[0084] S43. Conduct quality inspection and bearing capacity assessment. Finally, conduct reinforcement effect detection to ensure that the foundation reaches the expected bearing capacity and check the fixing status of the anchor pipes to ensure the long-term project stability.

[0085] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A double-liquid sac grouting construction method capable of shell expansion and temporary plugging, characterized in that: The steps include: S1, opening a hole and inserting a double-bladder grouting anchor pipe; S11, arrange drilling holes and control the positions and specifications of drilling holes according to working conditions; S12, installing the double liquid bag grouting anchor pipe; S2, filling the fluid to expand the bladder 1 and the bladder 2; S21, selecting a fluid and injecting the fluid; S22, balloon 1 and balloon 2 expand; S23, metal shell protection strip unfolds; S3, high pressure grouting; S31, performing plugging control and adjusting grouting pressure; S32, slurry injection and diffusion; S33, splitting-compacting reinforcement; S4, slurry solidification and tail tray fixation; S41, perform curing monitoring and strength assessment; S42, fix the tail tray and anchor it permanently; S43. Conduct quality inspection and load-bearing capacity assessment.

2. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 1 is characterized in that: When anchoring the tunnel surrounding rock, Step S11 needs to determine the position according to the surrounding rock characteristics and reinforcement requirements, and the boreholes are arranged along the side wall or arch; the drilling angle is adjusted according to the stability of the surrounding rock, and the drilling is carried out in an oblique downward, horizontal or oblique upward direction; the borehole diameter is 1.2 to 1.5 times the diameter of the double liquid bag grouting anchor pipe, and after the drilling is completed, the debris, loose rock and accumulated water in the borehole are cleaned; In step S12, the double liquid bladder grouting anchor pipe is inserted into the borehole so that bladder body 1 and bladder body 2 are located in the target anchoring area; during the insertion process, the double liquid bladder grouting anchor pipe is ensured to be inserted in the axial center position and the tail tray is close to the hole opening.

3. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 2 is characterized in that: In step S21, inert gas, water or cement slurry is injected into the bladder through the infusion tube; if the tunnel surrounding rock is water-rich surrounding rock, cement slurry is selected; in step S22, after the fluid enters bladder one and bladder two, bladder one and bladder two gradually expand and fit tightly to the hole wall; in step S23, after bladder one and bladder two expand, the metal shell protection strip opens synchronously to form an umbrella-shaped barb structure.

4. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 3 is characterized in that: In step S31, a graded pressurization mode is adopted to gradually increase the grouting pressure; in step S32, during the high-pressure grouting process, the grouting pressure is above 3 MPa; if the tunnel surrounding rock is water-rich fine sand surrounding rock or red layer surrounding rock in central Yunnan, the rheological properties of the slurry need to be adjusted; in step S33, the high-pressure slurry is released along the grouting holes to allow the slurry to diffuse along the cracks in the surrounding rock to increase the anchoring range.

5. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 1 is characterized in that: When treating soft soil, In step S11, vertical downward drilling is used to drill holes for overall reinforcement of the foundation; inclined downward drilling is used to stabilize and reinforce the slope; the drilling diameter is 1.2 to 1.3 times the diameter of the double-bladder grouting anchor pipe; In step S12, after the drilling is completed, loose sediments are removed and the double liquid bag grouting anchor pipe is inserted so that the bag one and the bag two are in the target reinforcement area; during the installation process of the double liquid bag grouting anchor pipe, ensure that the double liquid bag grouting anchor pipe is inserted vertically or at the designed angle so that the tail tray is close to the ground surface.

6. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 5 is characterized in that: In step S21, gas, water or cement slurry is injected into the bladder through the infusion tube, so that the bladders 1 and 2 expand evenly and fit tightly to the hole wall; if the soft foundation flow is sandy soil, cement slurry is used; in step S22, after the bladders 1 and 2 expand, the pores are filled to form a local dense area; for soft foundations with plastic clay or high water content, the expansion pressure needs to be adjusted to prevent soil disturbance; in step S23, after the bladders 1 and 2 expand, the metal shell protection strips are opened synchronously to form an umbrella-shaped barbed structure.

7. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 6 is characterized in that: In step S31, after the bladders 1 and 2 are fully expanded, a plug is formed, and the grouting pressure is 1.5-2.5 MPa.

8. The double-liquid-bag grouting construction method capable of shell expansion and temporary plugging according to claim 7 is characterized in that: In step S41, the curing process is monitored after the slurry is injected to ensure that the grouting material reaches the designed strength within the specified time; if the slurry is a single-liquid slurry of sulphoaluminate cement, the initial setting time is 35 minutes to 45 minutes; if the slurry is a cement water glass material, the initial setting time is 40 seconds; in step S42, after the slurry is completely solidified, the tail tray is used to fix the anchor pipe.

9. A double-liquid-bag grouting anchor pipe device capable of shell expansion and temporary plugging, which adopts the grouting construction method of claim 4 or claim 8 for grouting operation, characterized in that: It comprises a double-liquid-bag hollow grouting anchor pipe and a bladder body 1 and a bladder body 2 arranged on the double-liquid-bag hollow grouting anchor pipe, wherein the bladder body 1 is arranged close to the front end of the anchor pipe, and the bladder body 2 is arranged close to the rear end of the anchor pipe; both the bladder body 1 and the bladder body 2 are provided with metal shell protection strips, and the rear ends of the metal shell protection strips include piercing strips; a plurality of slurry outlets located on the double-liquid-bag hollow grouting anchor pipe are evenly opened between the bladder body 1 and the bladder body 2; a front end side bladder body filling channel connected with the bladder body 1 and a rear end side bladder body filling channel connected with the bladder body 2 are provided on the outer wall of the double-liquid-bag hollow grouting anchor pipe.

10. The double-liquid-bag grouting anchor pipe device capable of expanding the shell and temporarily plugging according to claim 9 is characterized in that: The front ends of the bladder body 1, bladder body 2, slurry outlet, and double liquid bladder hollow grouting anchor pipe are all located within the pre-drilled hole boundary of the anchoring medium, and the tail end boundary of the pre-drilled hole boundary is close to the tail end of the anchor pipe; the front end side bladder body filling channel and the tail end side bladder body filling channel both extend to the outside of the tail end boundary of the pre-drilled hole boundary; the tail end of the anchor pipe is provided with a pressure-resistant ball valve for controlling the flow of fluid in the front end side bladder body filling channel and the tail end side bladder body filling channel.

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