A backward type mold bag sectional grouting device and a grouting method

Abstract

The application provides a retreating type mold bag sectional grouting device and a grouting method, and the device comprises a center grouting pipe for initial positioning and anchoring grouting at the end, an anchoring assembly arranged at the end of the center grouting pipe and used for initial positioning in a drill hole, a separation assembly arranged outside the center grouting pipe and used for establishing dynamic sectional isolation, and a ball-controlled sectional grouting assembly arranged inside the separation assembly and used for grouting different grouting areas. The application is aimed at the uneven distribution of weak areas in the stratum, the position of the grouting area is freely controlled by adjusting the position of the separation air bag and the flower hole pipe, controllable grouting in the specified stratum range is realized, the grouting accuracy and flexibility of each grouting area are improved, and the grouting control of special complex stratum is met. Meanwhile, the retreat sleeve is arranged, is gradually drawn out in the grouting process, recycling and secondary use are realized, and the construction cost can be reduced.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering technology, and in particular to a retractable manhole cover segmented grouting device and grouting method. Background Technology

[0002] When excavating in soft soil strata, grouting reinforcement technology is the best way to solve adverse geological problems and improve stratum stability. It is widely used in stratum reinforcement due to its strong adaptability to different strata and its economic efficiency. However, with the increasing application of grouting reinforcement in tunnel engineering, problems such as uncontrollable grout diffusion, waste and pollution, irregular morphology of the reinforced body, poor mechanical stability, and weak adaptability to soft soil strata and underwater environments are difficult to solve. These problems are typically addressed using the geotextile bag grouting method to achieve the desired reinforcement effect.

[0003] Many shortcomings have been found in the use of existing geotextile grouting: First, the effect of stopping grout and sealing holes during construction is poor, and excessive sealing pressure in soft strata may lead to hole collapse; second, there are environmental and economic defects, as the materials used cannot be recycled.

[0004] Therefore, when studying segmented grouting of receding mold bags, it is crucial to flexibly control the grouting area and achieve material reuse. Summary of the Invention

[0005] In view of this, the present invention proposes a retractable segmented grouting device and grouting method for mold bags.

[0006] Specifically, the retractable segmented grouting device for molded bags includes:

[0007] The central grouting pipe is used for initial end positioning and anchoring grouting.

[0008] An anchoring assembly for initial positioning in the borehole is provided at the end of the central grouting pipe;

[0009] A separation component for establishing dynamic segmented isolation is installed outside the central grouting pipe;

[0010] And a ball-controlled segmented grouting assembly disposed inside the partition assembly for grouting different grouting zones.

[0011] Based on the above solution, the anchoring assembly includes:

[0012] An anchoring mold bag is provided at the end of the central grouting pipe for expanding after grout injection to anchor within the borehole.

[0013] A fastening limiting ring is provided at one end of the anchoring mold bag to enhance the stability of the anchoring mold bag;

[0014] A rubber disc is provided at one end of the fastening limiting ring to limit the central grouting pipe to the center of the borehole.

[0015] Based on the above scheme, the separating component includes:

[0016] A retractable sleeve for supporting the partition air bag is fitted onto the central grouting pipe;

[0017] Several separating air bags are provided on the retracting sleeve to form an annular isolation zone after inflation;

[0018] And a vent pipe for inflating and deflating gas is provided on the partitioned air bag.

[0019] Based on the above scheme, the separating air bag is a double-layer rubber bladder structure that expands in two directions, namely towards the borehole wall and the retracting sleeve, after inflation. The double-layer rubber bladder structure includes an outer rubber bladder for pressing against the borehole wall outward after inflation and an inner rubber bladder for pressing against the outer wall of the retracting sleeve inward after inflation.

[0020] Based on the above solution, the separating air bag further includes:

[0021] A first rubber ring and a second rubber ring are provided at both ends of the outer rubber bladder and the inner rubber bladder.

[0022] Based on the above scheme, the ball-controlled segmented grouting assembly includes: multiple sets of spliced ​​segmented grouting pipes and a partition ball inside the segmented grouting pipes for blocking the grouted area.

[0023] Based on the above scheme, the segmented grouting pipe includes:

[0024] A perforated tube for slurry outflow is installed inside the retracting sleeve;

[0025] A limiting tube is provided at the distal end of the perforated tube to prevent the movement of the separating ball;

[0026] A rubber sleeve is provided on the outside of the perforated tube to initially seal the slurry outlet holes on the perforated tube;

[0027] Connecting steel pipes for splicing are provided at both ends of the limiting tube and the perforated tube.

[0028] Based on the above scheme, it also includes: a rubber jacket for the grouting pipe provided on the outside of the perforated pipe for initial sealing and protection of the grout outlet.

[0029] In addition, the present invention also provides a retractable segmented grouting method for molded bags, which employs the aforementioned retractable segmented grouting device for molded bags and includes the following steps:

[0030] S1. Initial Anchoring: After completing the drilling operation, the borehole wall is thoroughly cleaned to remove any residue. Then, the anchoring components are assembled to the front end of the central grouting pipe in sequence. After that, the anchoring components are precisely lowered to the design depth, and the grouting equipment is connected to carry out the grouting operation of the anchoring formwork. Once the grouting pressure is stable, the initial anchoring position in the borehole is completed.

[0031] S2. Establish dynamic segmented isolation: Configure several isolation air bags on the retreating sleeve and install them coaxially with the central grouting pipe. Adjust the axial position to make the first isolation air bag precisely aligned with the boundary of the first grouting area. Then, inject gas into the isolation air bags through an air pump to form an annular isolation zone.

[0032] S3. Segmented grouting and dynamic retreat: The first segment of grouting is carried out through the segmented grouting pipe. After the grouting pressure stabilizes, the separator ball is immediately put in to block the pipeline. Then the gas in the separator air bag is released, the retreat sleeve is removed, the separator air bag is re-inflated to establish a new isolation barrier, and the retreat sleeve is precisely positioned to the next grouting area.

[0033] The above operations are repeated during subsequent grouting processes until the grouting is completed.

[0034] Based on the above scheme, the S3 segmented grouting step further includes:

[0035] After grouting in the current grouting area is completed, increase the grouting pressure to rupture the rubber jacket of the grouting pipe, allowing the grout to diffuse into the next grouting area.

[0036] Compared with existing technologies, this invention addresses the problem of uneven distribution of weak areas in strata. By adjusting the positions of the separating air bags and perforated pipes, the location of the grouting area can be freely controlled, enabling controllable grouting within a specified stratum area. This improves the grouting accuracy and flexibility of each grouting area, meeting the grouting control requirements of special and complex strata. Furthermore, by incorporating a retractable sleeve device, it can be gradually withdrawn during the grouting process, ultimately allowing for recycling and reuse, thus reducing construction costs. The segmented grouting pipe is composed of a series of steel pipes of different lengths, which can be adjusted and flexibly set according to requirements. This enables precise control of weak areas, facilitates transportation and on-site installation, and is simple to manufacture, low in cost, easy to operate, and improves construction efficiency. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a retractable segmented grouting device for a molded bag, according to an exemplary embodiment.

[0038] Figure 2 This is a schematic diagram of the structure of a separator component according to an exemplary embodiment;

[0039] Figure 3This is a cross-sectional view of a separating component according to an exemplary embodiment (showing an outer rubber bladder and an inner rubber bladder).

[0040] Figure 4 This is a schematic diagram of the structure of a retractable sleeve according to an exemplary embodiment;

[0041] Figure 5 This is a schematic diagram of the structure of a ball-controlled segmented grouting assembly according to an exemplary embodiment;

[0042] Figure 6 This is a cross-sectional view of a ball-controlled segmented grouting assembly according to an exemplary embodiment. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not constitute any limitation thereof.

[0044] Example 1

[0045] This application provides a specific embodiment of a retractable segmented grouting device for molded bags, such as... Figure 1 The aforementioned retractable segmented grouting device for molded bags includes:

[0046] The central grouting pipe 11 is used for initial end positioning and anchoring grouting;

[0047] An anchoring assembly for initial positioning in the borehole is provided at the end of the central grouting pipe 11.

[0048] A separation component for establishing dynamic segmented isolation is provided outside the central grouting pipe 11;

[0049] And a ball-controlled segmented grouting assembly disposed inside the partition assembly for grouting different grouting zones.

[0050] As a specific implementation, the anchoring assembly includes an anchoring mold bag 1 at the end of the central grouting pipe 11 for expanding after grout injection to anchor within the borehole, a fastening limiting ring 2 at one end of the anchoring mold bag 1 for enhancing its stability, and a rubber disc 3 at one end of the fastening limiting ring 2 for confining the central grouting pipe 1 to the center of the borehole. After drilling the grouting hole, the central grouting pipe 11, which is bound with the anchoring mold bag 1 and fitted with the fastening limiting ring 2 and the rubber disc 3, is first inserted into the grouting hole, and grout is injected into the anchoring mold bag 1 until it expands to fill the top of the grouting hole.

[0051] The central grouting pipe 11 is made of seamless stainless steel pipe and serves as the core pressure-bearing channel of the entire grouting device. The anchoring formwork 1 installed at its front end is made of long-filament woven geotextile material and is fixed to the outer wall of the anchoring formwork 1 by steel wire binding to form an expandable anchoring structure. A rubber disc 3 and a fastening limiting ring 2 are set in sequence behind the anchoring formwork 1: the rubber disc 3 is a disc structure with a central hole, the opening size of which matches the central grouting pipe 11, and plays a positioning and centering role; the fastening limiting ring 2 is a specially designed rubber ring with a uniform outer diameter and a hollow frustum-shaped structure with a larger front and smaller rear inner diameter, which generates a wedge-shaped squeezing effect when the anchoring formwork 1 expands during grouting, effectively preventing the anchoring formwork 1 from sliding backward; these three are closely arranged along the axial direction of the central grouting pipe 11 to form a reliable anchoring component.

[0052] like Figure 2 As shown in the illustration, in a specific embodiment, the separation assembly includes a retractable sleeve 6 fitted onto the central grouting pipe 11 for supporting the separation air bags 7, a plurality of separation air bags 7 installed on the retractable sleeve 6 for forming an annular isolation zone, and vent pipes for inflation and deflation provided on the separation air bags 7. A sealing plate 5 is provided at the end of the retractable sleeve 6.

[0053] In existing technologies, the conventional grouting process uses ordinary mold bag structures where the mold bag expands unidirectionally and comes into contact with the grout during the grouting process. Once the grout solidifies, it is difficult to move. To solve this technical problem, such as... Figure 3 As shown, in a specific implementation of the separator air bag 7, the separator air bag 7 is a double-layer rubber bladder structure that expands in two directions, namely towards the borehole wall and the retracting sleeve 6, after inflation. The double-layer rubber bladder structure includes an outer rubber bladder 701 for pressing against the borehole wall outward and an inner rubber bladder 702 for pressing against the outer wall of the retracting sleeve 6 inward.

[0054] The aforementioned bidirectional sealing design forms a complete annular isolation zone within the borehole, completely isolating the grouting area from the preceding and following areas. The inner side expands and adheres tightly to the retracting sleeve 6, while the outer side expands and adheres close to the borehole wall, dividing the front end into a small grouting area and preventing grout from spreading to other areas. During use, each inflated separator 7 divides an independent grouting zone along the borehole axial direction, ensuring that the grout can only spread within the current target zone. Furthermore, after grouting is completed, the separator 7 deflates and contracts, temporarily releasing the barrier; after the retracting sleeve 6 is removed, the separator 7 can be re-inflated to form a new barrier, serving as a reusable temporary barrier. During deflation, the outer rubber bladder 701 contracts slowly due to contact with the solidified grout, while the inner rubber bladder 702 can quickly separate from the retracting sleeve 6, ensuring smooth removal of the retracting sleeve 6 without compromising the barrier's integrity.

[0055] To ensure the airtightness of the double-layer rubber bladder structure, the separator airbag 7 also includes a first rubber ring 703 and a second rubber ring 704 at both ends of the outer rubber bladder 701 and the inner rubber bladder 702. Specifically, the double-layer rubber bladder structure is suspended in the annular space between the borehole wall and the retracting sleeve 6, and does not contact any surface before inflation; a vent pipe is provided at the rear end of the separator airbag 7, passing through the rubber ring and directly into the bladder, for precise control of the inflation operation; the entire separator airbag 7 is fitted onto the outer wall of the retracting sleeve 6 and has axial sliding function, allowing for flexible adjustment of its position on the retracting sleeve 6 according to grouting requirements.

[0056] The method for manufacturing and using the above-mentioned air-splitting bag 7 is as follows:

[0057] (1) According to Figure 2 The series of separator air bags 7 shown are threaded side by side on the retracting sleeve 6. When the separator air bags 7 are not inflated, they can move freely and their positions can be adjusted.

[0058] (2) According to Figure 3 As shown, the series of partitioned air bags 7 are processed by fastening the first rubber ring 703 and the second rubber ring 704 at both ends to seal the outer rubber bladder 701 and the inner rubber bladder 702.

[0059] (3) A limiting structure 18 is welded on the retracting sleeve 6 to send the series of partition air bags 7 into the grouting hole;

[0060] (4) The vent pipe passes through the first rubber ring 703 and the second rubber ring 704 to inflate the partition air bag 7, and the other end is connected to the air pump outside the grouting hole;

[0061] During use, after the first stage of grouting is completed, in order to allow the retractable sleeve 6 to be easily extracted, the double-layer rubber bladder structure of the separating air bag 7 comes into contact with different media. The outer rubber bladder 701 comes into contact with the front cement slurry, and the inner rubber bladder 702 comes into contact with the retractable sleeve 6. After the slurry has slightly solidified, the mold bag is shrunk. The outer rubber bladder 701 is stuck to the cement slurry, and the inner rubber bladder 702 can shrink freely, so that the retractable sleeve 6 can be extracted freely.

[0062] like Figure 4 As shown, the retracting sleeve 6 is a sleeve structure with a front-end welded steel plate. Its overall diameter is three times that of the central grouting pipe 11, forming an ample annular working space. Two holes are precisely opened on the steel plate. The central hole is for the central grouting pipe 11 to pass through, and the side hole is located at 2 / 3 of the radius from the center, reserving a channel for subsequent operations.

[0063] The working principle of the above-mentioned separator air bag 7 is as follows:

[0064] The outer rubber bladder 701 and the inner rubber bladder 702 in the air-splitting bag 7 expand to both sides in the radial direction. The inner rubber bladder 702 expands and sticks tightly to the retracting sleeve, while the outer rubber bladder 701 expands and sticks close to the wall of the grouting hole, dividing the front end into a small grouting area and preventing the grout from spreading to other areas.

[0065] After the drilling of the grouting hole is completed, the central grouting pipe 11, which is tied with the anchoring mold bag 1 and fitted with the fastening limit ring 2 and the rubber disc 3, is placed into the grouting hole and grouting is performed on the anchoring mold bag 1 until it expands to fill the top of the grouting hole.

[0066] After the anchoring mold bag 1 expands and takes shape, close the valve of the central grouting pipe, and install the retracting sleeve 6, as well as a series of partition air bags 7 and segmented grouting pipes 4 on the retracting sleeve;

[0067] The outer rubber bladder 701 and the inner rubber bladder 702 expand radially respectively. After the inner side expands, it adheres tightly to the retracting sleeve 6, and after the outer side expands, it adheres tightly to the borehole wall, dividing the front end into an independent grouting area and preventing the grout from spreading to other areas.

[0068] After the first stage of grouting is completed, in order to enable the retractable sleeve 6 to be easily pulled out, the two rubber bladders of the separating air bag 7 are in contact with different media. The outer rubber bladder 701 is in contact with the front cement slurry, and the inner rubber bladder 702 is in contact with the retractable sleeve 6. After the slurry solidifies slightly, the separating air bag 7 contracts. The outer rubber bladder 701 is stuck to the cement slurry, and the inner rubber bladder 702 can contract freely, so that the retractable sleeve 6 can be pulled out freely.

[0069] After the retracting sleeve 6 is pulled out, the separating air bag 7 is immediately inflated again to stop the slurry.

[0070] like Figure 5 As shown in the illustration, in a specific implementation, the ball-controlled segmented grouting assembly includes multiple sets of spliced ​​segmented grouting pipes 4 and a partition ball 17 inside the segmented grouting pipes 4 for blocking the grouted area. The segmented grouting pipes 4 include a perforated pipe 15 for grout outflow within the retracting sleeve 6, a limiting pipe 12 at the distal end of the perforated pipe 15 for blocking the movement of the partition ball 17, a rubber jacket 14 outside the perforated pipe 15 for initially sealing the grout outlet 16 on the perforated pipe 15, and connecting steel pipes 13 at both ends of the limiting pipe 12 and the perforated pipe 15 for splicing.

[0071] Among them, the perforated tube 15 is a steel pipe with threads at both ends, and several slurry outlet holes 16 are opened on the perforated tube 15; the limiting tube 12 is a steel pipe with threads at both ends, the outer diameter of the limiting tube 12 is the same as that of the connecting steel pipe 13, and the inner diameter of the limiting tube 12 is determined by the size of the separating ball 17. The limiting tube 12 can hold the separating ball 17 in place, and together with the separating ball 17, it plays the role of blocking the slurry; the separating ball 17 is a small steel ball, which has multiple models and is used in conjunction with the limiting tube 12.

[0072] The components of the segmented grouting pipe 4 are connected by threads. Each grouting unit consists of a pipe segment required for one grouting operation. The installation method for each grouting unit involves precisely threading the perforated pipe 15 (with grout outlet 16) to the connecting steel pipe 13 to form a basic flow channel structure. Then, a limiting pipe 12 is screwed onto the distal interface of the connecting steel pipe 13 to construct a ball valve isolation mechanism. Finally, a grouting pipe rubber sleeve 14 is fitted onto the perforated pipe 15 to achieve initial sealing protection for the grout outlet 16. The grouting units are connected end-to-end via the connecting steel pipe 13, ultimately integrating into a ball-controlled segmented grouting assembly that can be flexibly expanded according to the drilling depth.

[0073] This invention utilizes a limiting tube to directly block the separating ball, thereby separating the grouting pipe; at the same time, it adopts a novel approach combining a retractable sleeve 6 and a separating air bag 7, wherein the position of the separating air bag 7 can be manually adjusted to flexibly control the grouting area; and the retractable sleeve 6 is gradually withdrawn during the segmented grouting process, which can realize the reuse of materials.

[0074] Example 2

[0075] A retractable segmented grouting method for geotextile bags, using the device described in Example 1, taking a three-segment grouting area as an example, includes the following steps:

[0076] S1. Initial Anchoring: After completing the drilling operation, the borehole wall is thoroughly cleaned to remove any residue and ensure that the borehole channel is unobstructed. Then, the anchoring components are assembled to the front end of the central grouting pipe 11 in sequence. Finally, the assembly is precisely lowered to the design depth, and the grouting equipment is connected to carry out the anchoring formwork grouting operation. Once the grouting pressure is stable, the initial anchoring position in the borehole is completed.

[0077] S2. Establish dynamic segmented isolation: Several partition air bags 7 are configured on the retracting sleeve 6 and coaxially installed with the central grouting pipe 11. The first partition air bag 7 is precisely aligned with the boundary of the first grouting area 19 by adjusting the axial position. Then, the air pump injects gas into the partition air bag 7 through the air pipe, causing its double-layer rubber bladder structure to expand towards the borehole wall and the retracting sleeve 6 respectively, forming an annular isolation zone.

[0078] S3. Segmented grouting and dynamic retraction: The first segment of grouting is carried out through the segmented grouting pipe. After the grouting pressure stabilizes, the separator ball 17 is immediately put in to block the pipeline. Then the gas in the separator air bag 7 is released, the retraction sleeve 6 is withdrawn, the separator air bag 7 is re-inflated to establish a new isolation barrier, and at the same time the retraction sleeve 6 is precisely positioned to the next grouting area.

[0079] The above operations are repeated during subsequent grouting processes until the grouting is completed.

[0080] Each of the aforementioned partitioned air bags 7 is provided with a vent pipe. In this embodiment, taking three partitioned air bags 7 as an example, the vent pipes are respectively referred to as the first vent pipe 8, the second vent pipe 9, and the third vent pipe 10.

[0081] The specific steps are as follows:

[0082] (1) After the drilling is completed, the hole wall is cleaned to ensure that there are no debris blocking the hole, so as to create unobstructed conditions for the subsequent installation of the device;

[0083] (2) Assemble the anchoring mold bag 1, the fastening limiting ring 2 and the rubber disc 3 to the front end of the central grouting pipe 11 in sequence: the anchoring mold bag 1 is fixed to the end of the central grouting pipe 11 by binding; the fastening limiting ring 2 is used to prevent displacement by squeezing the first rubber ring 703 and the second rubber ring 704 when the mold bag expands; the rubber disc 3 plays a central positioning role; slowly lower the assembled central grouting pipe 11 to the design depth to ensure that the anchoring mold bag 1 is accurately located at the preset anchoring position;

[0084] (3) Connect the external grouting equipment using a sealed joint, and start the grouting pump to inject grout into the central grouting pipe 11. After the grouting pressure stabilizes to the design value and is maintained for a certain period of time, the grouting process of the anchoring formwork 1 is completed;

[0085] (4) After the anchoring system is in place, install the partition system and the ball-controlled segmented grouting system.

[0086] For the design of the three-stage grouting area, three partition air bags 7 are configured on the retreating sleeve 6;

[0087] Install the retractable sleeve 6 with the air bag on the same axis as the central grouting pipe 11, adjust its position so that the first dividing air bag 7 is located at the rear end of the first grouting area 19, and connect the segmented grouting pipe 4 to the external grouting equipment simultaneously.

[0088] (5) The air pump inflates the first partition air bag 7 through the first air pipe 8, so that its outer wall is tightly attached to the hole wall and its inner wall is attached to the retracting sleeve 6, forming a sealed isolation barrier in the first grouting area 19; the inflation pressure needs to be precisely controlled to ensure the reliability of the seal while avoiding damage to the hole wall or air bag.

[0089] Work flow for the first grouting zone 19:

[0090] (6) Start the grouting equipment and inject grout into the first grouting area 19 through the segmented grouting pipe 4. Monitor the filling status in real time. When the grouting pressure is stable at the design value, the grouting of this segment is determined to be completed.

[0091] (7) After grouting stops, insert the No. 1 separator ball 17 into the segmented grouting pipe 4 to block the grout from spreading to the first section area during the second grouting process; release the gas in the first separator air bag 7 through the air pump, and use its double-layer rubber bladder structure to differentiate the shrinkage characteristics (the outer layer is stuck to the grout and shrinks slowly, while the inner layer quickly detaches from the sleeve) to pull the retracting sleeve 6 outward; after the first separator air bag 7 detaches from the retracting sleeve 6, it is immediately re-inflated to form a new barrier, and the retracting sleeve 6 is pulled to the front end of the next grouting area to prepare for the second grouting.

[0092] Second grouting zone 20 operation process:

[0093] (8) Gas is injected into the second frontmost air bag 7 by an air pump, so that the outer wall of the air bag is tightly attached to the hole wall and the inner wall is tightly attached to the retracting sleeve, forming an isolation barrier for the second grouting area.

[0094] (9) Before the second grouting begins, increase the grouting pressure to P2, which will break the rubber jacket 14 of the first grouting pipe and allow the grout to diffuse into the second grouting area 20.

[0095] (10) After grouting stops, insert the second separator ball 17 into the segmented grouting pipe 4; the air pump releases the gas in the separator air bag 7 through the second air pipe 9, and takes advantage of the differential shrinkage characteristics of its double-layer rubber bladder structure (the outer layer is stuck to the grout and shrinks slowly, while the inner layer quickly detaches from the sleeve) to pull the retracting sleeve 6 outward; after the separator air bag 7 detaches from the retracting sleeve 6, it is immediately re-inflated to form a new barrier, and the retracting sleeve 6 is pulled to the front end of the next grouting area to prepare for the third grouting section.

[0096] Work flow for the third grouting zone 21:

[0097] (11) Gas is injected into the third frontmost air bag 7 by an air pump, so that the outer wall of the air bag is tightly attached to the hole wall and the inner wall is tightly attached to the retracting sleeve, forming an isolation barrier in the third grouting area.

[0098] (12) Before the third grouting begins, increase the grouting pressure and adjust it to P1 (P2 < P1) to puncture the rubber jacket 14 of the second grouting pipe, so that the grout can diffuse into the third grouting area 21.

[0099] (13) After grouting stops, the No. 3 separator ball 17 is put into the segmented grouting pipe 4 to block the grout from spreading to the second grouting area 20 during the third grouting process; the air pump releases the gas in the third separator air bag 7 through the third air pipe 10, and pulls the retracting sleeve 6 and the segmented grouting pipe 4 out of the borehole to complete all grouting operations.

[0100] Example 3

[0101] Based on the retractable segmented grouting method for the mold bag in Example 2, in this example, as Figures 5-6 As shown, the grouting method of the above-mentioned segmented grouting pipe 4 includes:

[0102] 1. Fabrication of segmented grouting pipes

[0103] Based on the site requirements, the diameter, number of pipe segments, and total length of the grouting pipe 4 are determined. In this embodiment, three segments are selected as the number of grouting segments.

[0104] Material preparation: Connecting steel pipe 13 serves as the structural framework; the diameter of perforated pipe 15 must be precisely designed to be smaller than that of the connecting steel pipe to form a flow channel transition; the outer diameter of the three grout outlet rubber sleeves 14 must be consistent with the grouting pipe system to ensure smooth passage through the pre-reserved opening at the front end of the retracting sleeve 6; the limiting pipe 12 serves as a key component of the mechanical valve; and a steel sealing ball is selected as the separator ball 17, utilizing its high-density characteristics to achieve effective grout sealing. All components must meet the dimensional accuracy and pressure resistance requirements of modular assembly.

[0105] Based on their installation locations, from the outside to the inside, the separator balls are named Q1 and Q2, the limiting tubes are named G1 and G2, the diameters of the separator balls are denoted as DQ1 and DQ2, and the inner diameters of the limiting tubes are denoted as DG1 and DG2.

[0106] A perforated pipe 15 is installed at the front end of a connecting steel pipe 13. A grouting pipe rubber sleeve 14 is fitted over the perforated pipe. A limiting pipe 12 is then installed at the front end of the perforated pipe 15. The perforated pipe 15 and the limiting pipe 12 are connected by a connecting steel pipe 13, ensuring that the dividing ball 17 will not block the grouting hole when blocked. This constitutes one grouting unit. Each unit is spliced ​​together with connecting steel pipes 13 to form a complete segmented grouting pipe 4. During the grouting process, dividing balls of different sizes are placed into the grouting pipe in sequence.

[0107] 2. According to Figure 5The assembled sectional grouting pipe shown is composed of a perforated pipe 15, a connecting steel pipe 13, a limiting pipe 12, and a rubber outer sleeve 14 of the grouting pipe. The specific installation method is to install the perforated pipe 15 at the front end of a section of the connecting steel pipe 13, install the rubber outer sleeve 14 of the grouting pipe outside the perforated pipe 15, then install a section of the connecting steel pipe 13 at the front end of the perforated pipe 15, and then install the limiting pipe 12 at the front end; each unit is connected by the connecting steel pipe 13.

[0108] As Figure 6 shown, in the sectional grouting pipe 4, the dividing balls 17 are numbered Q1 and Q2 in sequence from the outside to the inside. The specific requirements for their diameters are: DG1 < DQ1 < DG2, DG2 < DQ2. With such a design, the dividing ball 17 can be stuck at the specified position (at the limiting pipe 12) to achieve slurry stoppage and section sealing, and the dividing ball 17 can smoothly pass through the next layer of the limiting pipe 12 during the grouting process to achieve layered advancement. Finally, the sectional grouting pipe 4 can inject slurry into the structure in sequence and by area, each layer can be effectively filled, and there is no slurry cross - flow between layers, achieving the engineering goal.

[0109] 3. After the construction of the anchoring system is completed, install the retracting sleeve 6 and the sectional grouting pipe 4 into the borehole and connect the grouting equipment.

[0110] 4. Inject gas into the first dividing air bag 7 at the very front end through an air pump, so that the outer wall of the dividing air bag 7 is closely fitted with the borehole wall, and the inner wall is closely fitted with the retracting sleeve 6, forming an isolation barrier for the first grouting area 19.

[0111] 5. Conduct sectional grouting. Start the grouting equipment and inject slurry into the first grouting area 19 through the sectional grouting pipe 4. During the grouting process, continuously monitor the slurry filling situation; after the grouting operation in the first grouting area 19 is completed, put the dividing ball 17 into the sectional grouting pipe 4. The dividing ball 17 is stuck on the limiting pipe 12, blocking the continuous diffusion of the slurry to the first grouting area 19.

[0112] 6. Release the air from the first dividing air bag 7. Since the contraction speeds of the inner and outer rubber capsules are different, the outer rubber capsule 701 contacts the grouting area and has a small contraction amplitude under the influence of the slurry. The inner rubber capsule 702 contacts the retracting sleeve 6 and can smoothly contract and separate from the retracting sleeve 6 when air is pumped out.

[0113] Pull the retracting sleeve 6 outwards. After the first dividing air bag 7 is separated from the retracting sleeve 6, immediately inflate the dividing air bag 7 to re - form the isolation barrier; wait until the retracting sleeve 6 is pulled to the front position of the next grouting area to prepare for the second - stage grouting.

[0114] 7. Inject gas into the second dividing air bag 7 at the very front end through an air pump, so that the outer wall of the dividing air bag 7 is closely fitted with the borehole wall, and the inner wall is closely fitted with the retracting sleeve 6, forming an isolation barrier for the second grouting area 20.

[0115] 8. Increase the grouting pressure to P2, so that the grout breaks through the rubber jacket of the grouting pipe and diffuses into the second grouting area 20.

[0116] In the above scheme, the rubber jacket 14 of the grouting pipe needs to rupture after the grouting pressure reaches a certain value. The two rubber jackets 14 of the grouting pipe are numbered T1 and T2 from the outside to the inside. T1 ruptures when the grouting pressure reaches P1, and T2 ruptures when the grouting pressure reaches P2. In order to avoid the grouting pressure causing the rubber jacket 14 to rupture prematurely during the normal grouting process, P1 and P2 need to be greater than the normal grouting pressure, and P1>P2.

[0117] 9. Repeat steps 5-8 to proceed backwards and complete the grouting of each grouting section in sequence.

[0118] This invention addresses the problem of uneven distribution of weak areas in strata. By adjusting the positions of the separating air bag 7 and the perforated pipe 15, the position of the grouting area can be freely controlled, enabling controllable grouting within a specified stratum range. This improves the grouting accuracy and flexibility of each grouting area, meeting the grouting control requirements of special and complex strata. Furthermore, by setting up a retractable sleeve 6, it can be extracted step by step during the grouting process, ultimately achieving recycling and reuse, which can reduce construction costs.

[0119] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention are within the scope of the present invention.

Claims

1. A retractable segmented grouting device for molded bags, characterized in that, include: The central grouting pipe (11) is used for initial positioning and anchoring grouting at the end. An anchoring assembly for initial positioning in the borehole is provided at the end of the central grouting pipe (11); A separation assembly for establishing dynamic segmented isolation is provided outside the central grouting pipe (11); and a ball-controlled segmented grouting assembly disposed inside the partition assembly for grouting different grouting areas; The anchoring assembly includes: An anchoring mold bag (1) is provided at the end of the central grouting pipe (11) for expanding after grout injection to anchor in the borehole. A fastening limiting ring (2) is provided at one end of the anchoring mold bag (1) to enhance the stability of the anchoring mold bag (1); A rubber disc (3) is provided at one end of the fastening limiting ring (2) to limit the central grouting pipe (11) to the center of the borehole. The separation component includes: A retractable sleeve (6) for supporting the partition air bag (7) is fitted on the central grouting pipe (11). A plurality of partition air bags (7) are provided on the retracting sleeve (6) for forming an annular isolation zone after inflation; and a vent pipe for inflation and deflation provided on the partitioned air bag (7); The separator air bag (7) is a double-layered rubber bladder structure that expands in two directions, namely towards the borehole wall and the retracting sleeve (6), after being inflated. The double-layer rubber bladder structure includes an outer rubber bladder (701) for pressing against the borehole wall outward after inflation and an inner rubber bladder (702) for pressing against the outer wall of the retracting sleeve (6) inward after inflation. The ball-controlled segmented grouting assembly includes: multiple sets of spliced ​​segmented grouting pipes (4) and a partition ball (17) inside the segmented grouting pipes (4) for blocking the grouted area. The separator air bag (7) also includes: A first rubber ring (703) and a second rubber ring (704) are provided at both ends of the outer rubber bladder (701) and the inner rubber bladder (702). The segmented grouting pipe (4) includes: A perforated tube (15) for slurry outflow is provided inside the retracting sleeve (6); A limiting tube (12) is provided at the distal end of the perforated tube (15) to prevent the movement of the separating ball (17). A rubber jacket (14) is provided on the outside of the perforated tube (15) for initially sealing the slurry outlet (16) on the perforated tube (15); Connecting steel pipes (13) for splicing are provided at both ends of the limiting tube (12) and the perforated tube (15).

2. A retractable segmented grouting method for molded bags, employing the retractable segmented grouting device for molded bags as described in claim 1, characterized in that, Includes the following steps: S1. Initial anchoring: After completing the drilling operation, the hole wall is thoroughly cleaned to remove residues. Then, the anchoring components are assembled to the front end of the central grouting pipe (11) in sequence. After that, the anchoring components are accurately lowered to the design depth and the grouting equipment is connected to carry out the grouting operation of the anchoring mold bag (1). After the grouting pressure is continuously stable, the initial anchoring position in the borehole is completed. S2. Establish dynamic segmented isolation: Configure several partition air bags (7) on the retreating sleeve (6) and install them coaxially with the central grouting pipe (11). Adjust the axial position so that the first partition air bag (7) is precisely aligned with the boundary of the first grouting area (19). Then, inject gas into the partition air bag (7) through the air pump to form an annular isolation zone. S3, Segmented grouting: The first segment of grouting is carried out through the segmented grouting pipe (4). After the grouting pressure stabilizes, the separator ball (17) is immediately put in to block the pipeline; the gas in the separator air bag (7) is released, the retracting sleeve (6) is removed, the separator air bag (7) is re-inflated to establish a new isolation barrier, and the retracting sleeve (6) is precisely positioned to the next grouting area. The above operations are repeated during subsequent grouting processes until the grouting is completed.

3. The retractable segmented grouting method for molded bags according to claim 2, characterized in that, The S3 segmented grouting step also includes: After grouting in the current grouting area is completed, increase the grouting pressure to puncture the rubber jacket (14) of the grouting pipe, so that the grout can spread to the next grouting area.

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