Inflation expansion type pile side karst cave blocking structure and method for karst pile foundation

Abstract

The invention relates to the technical field of geotechnical engineering in civil engineering, and discloses an inflatable expansion type pile side karst cave blocking structure and method.The structure comprises a flexible cloth bag, a top air bag, a bottom air bag, an air bag support, an air guide pipe, an air pump and an inflation pipe; welding is conducted on the outer portion of the reinforcement cage, the welded air bag support is sleeved with the annular air bag, the reinforcement cage is sleeved with the flexible cloth bag, and the supporting plate and the connecting belt are matched with each other, so that the supporting plate makes contact with the ground, and the reinforcing sleeve and the abutting plate are matched with each other. The problem of leakage in the concrete pouring process is avoided, fixed-point arrangement can be conducted according to the position of a karst cave, material consumption is reduced, and due to the fact that the flexible structure is suitable for drilling holes of different diameters, applicability is wide; manpower and material resources are saved, and the success rate of cloth bag pile construction is greatly increased.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical engineering in civil engineering, and in particular to an air-expandable pile-side karst cave blocking structure and method for a karst pile foundation. Background Art

[0002] Infrastructure construction in karst areas faces complex geological challenges. According to statistics, about 12% of the world's land area is karst, of which the karst coverage rate in southwest China is as high as over 30%. In pile foundation construction in such areas, caves, cracks and groundwater flows cause the over-injection rate of concrete to generally reach 15%-40%, and the cost of a single pile increases by 25%-60%. Although existing sealing technologies can form sealed cavities, they are limited by the randomness of the cave morphology (such as beaded caves accounting for 38%), and the positioning error of the support parts often exceeds 20cm, resulting in a sealing failure rate of up to 35%. Although the traditional steel casing follow-up process can cope with multi-layer caves, the cost per linear meter increases by 800-1200 yuan, and the construction period is extended by more than 40%. With the promotion of the green construction concept, the high energy consumption of existing technologies (single pile consumes more than 1.5 tons of steel) and ecological damage problems (mud discharge reaches 3-5m 3 / piles) have become a pain point in the industry's transformation.

[0003] In order to solve the above problems, patent document CN202210262217.4 discloses a bored pile forming device and method suitable for karst areas, which uses support members and concrete canvas as isolation materials to form a sealed cavity to seal the cave. The support members are difficult to accurately position and install. In the above-mentioned device and method, over-pouring concrete to fill the cave or steel casing to follow up to seal the cave will incur a lot of additional expenses, and it is time-consuming and labor-intensive, resulting in low construction efficiency. Among the new cave sealing technologies, bag pile technology has many advantages such as high construction efficiency and low price.

[0004] However, the full bagging method used in the existing technology not only consumes materials, but also cannot guarantee the complete blocking of the concrete flow channel outside the bag, resulting in serious over-filling of concrete during the construction process of the pile. The following problems still exist: (1) Geological adaptability defects: Cave identification error: When the traditional drilling sampling interval is greater than 5m, the cave miss rate reaches 22%, resulting in a design redundancy of more than 30% in the length of the steel casing. Dynamic water flow impact: When the groundwater flow rate is greater than 0.5m / s, the amount of concrete loss outside the bag pile increases by 3 times, and the strength of the grouting body decreases by 40% after 28 days. (2) Economic and sustainability shortcomings: Excessive material consumption: Fully wrapped bag piles consume 4.2-6.5kg of geotextile per meter, which is three times that of the segmented solution; the steel casing recovery rate is only 65%, and the cost of scrap steel processing is 800 yuan / ton. Carbon emissions exceeded the standard: the over-concrete process produces 380kg of CO2 per cubic meter, exceeding the green construction standard limit by 42%; (3) Process reliability issues Interface sealing failure: The permeability coefficient at the concrete canvas joint reached 1×10 -6 cm / s, and the probability of leakage exceeds 50% when the pressure head is greater than 10m. Limitations of intelligent technology: The existing monitoring system has a false alarm rate of 18% in multi-layer cave scenarios and cannot identify micro-cracks less than 5cm. Summary of the Invention

[0005] The purpose of the present invention is to provide an inflatable expandable pile side cave sealing structure and method for karst pile foundation, which solves the problem that the full bag method used in the background technology not only consumes materials but also cannot ensure complete sealing of the concrete flow channel outside the bag.

[0006] In order to solve the above technical problems, according to a first aspect of the present invention, there is provided an inflatable expandable pile-side cave plugging structure for karst pile foundation, comprising a flexible cloth bag, a top airbag, a bottom airbag, an airbag bracket, an air guide tube, an air pump and an inflation tube;

[0007] The flexible bag includes a high-strength geotextile, which is used to form a sealed space at the location of the cave. The top airbag and the bottom airbag are composed of an annular airbag and an air nozzle. The annular airbag is made of rubber material, and metal air nozzles are fixed on the upper and lower sides. There are small holes on the side for fixing the position of the bag. The bag is fixed by a thin wire. The annular airbag is used to expand the volume to support the bag. The air nozzle is used to connect the air guide tube to complete inflation and deflation. The air nozzle is connected to the air guide tube to achieve inflation and deflation, which can effectively expand the volume and support the bag.

[0008] The airbag bracket is made of steel, including a bottom plate and two side guard plates. When in use, the position is determined and then welded to the steel cage. The position of the airbag is limited in the airbag bracket. The upper and lower guard plates prevent the position of the airbag from changing during the lowering of the steel cage. The air guide tube is made of rubber material and is used to inflate and deflate the airbag. At the same time, the flexible cloth bag is made of high-strength geotextile, which can form a reliable sealed space at the cave location.

[0009] Preferably, the interior of the flexible cloth bag is provided with a plurality of evenly distributed steel bar bodies, and the outer walls of the steel bar bodies are wrapped with steel bar clamps. The steel bar bodies can enhance the overall structural strength of the cloth bag, enabling it to withstand greater external forces and pressures. The steel bar clamps further fix the steel bar bodies to prevent them from displacement or deformation during use, thereby improving the stability and reliability of the flexible cloth bag when forming a sealed space.

[0010] Preferably, a reinforcement sleeve is fixed to the outer wall of the air pump and the inflation tube, reinforcement rods are installed on both sides of the reinforcement sleeve, a support rod is fixed to one side of the reinforcement rod, a rotating rod is hinged to one side of the support rod, and a resistance plate is installed at the bottom of the rotating rod. When the air pump is working, the resistance plate is brought into contact with the ground or other supporting objects by rotating the rotating rod, thereby increasing the stability of the air pump and the inflation tube, preventing them from shaking or displacing during the inflation process, and ensuring the smooth progress of the inflation operation.

[0011] Preferably, a rotating mechanism is provided between the rotating rod and the support rod to facilitate the rotation of the rotating rod, the rotating mechanism includes a rotating groove opened on one side of the inner part of the support rod, a rotating seat is provided inside the rotating groove, and the rotating seat is fixed to the rotating rod, so that the rotating rod can flexibly rotate around the rotating seat in the rotating groove, and the angle of the rotating rod is conveniently adjusted to adapt to different support requirements, ensuring that the contact plate can accurately contact the support object, and enhancing the stability of the air pump and the inflation tube.

[0012] Preferably, linkage rods are installed on both sides of the rotating seat, and the two linkage rods extend to both sides of the support rod and are fixed with linkage sleeves. The top of the support rod is provided with a limiting assembly for limiting the rotating seat. The setting of the linkage sleeve and the linkage rod can make the rotation of the rotating rod more stable, and cooperate with the limiting assembly to fix the rotating rod after it is adjusted to a suitable position to prevent it from accidentally rotating during use, thereby ensuring the reinforcement effect of the air pump and the inflation tube.

[0013] Preferably, the limit assembly includes a limit plate arranged at the top of the support rod, and extension blocks are fixed on both sides of the limit plate. Bolts are threaded between the two extension blocks and the support rod. By tightening the bolts, the limit plate can be firmly fixed to the top of the support rod, thereby effectively limiting the rotating seat. This detachable connection method is convenient for operation when the angle of the rotating rod needs to be adjusted, thereby improving the flexibility of use of the device.

[0014] Preferably, two limit rods are fixed to the bottom of the support rod, and plug plates are fixed on both sides of the bottom of the support rod, and the two plug plates are plugged into the linkage sleeve. The limit rods extend to the interior of the rotating groove and are plugged into the rotating seat. The position of the rotating seat in the rotating groove is more stable, preventing it from shaking or shifting during rotation. At the same time, the plug-in cooperation with the plug plate and the linkage sleeve further enhances the connection strength between the rotating rod and the support rod, ensuring the stability of the air pump and the inflation tube in the reinforced state.

[0015] Preferably, a plurality of connecting belts are installed on the outer wall of the top of the flexible cloth bag, and a support plate is installed at the bottom of one end of the plurality of connecting belts. A plurality of evenly distributed mounting holes are opened around the bottom of the support plate. The connecting belts can connect the support plate to the flexible cloth bag, and the mounting holes on the support plate can be used to install other components or connect with other structures, thereby increasing the connectivity and stability of the sealing structure with the surrounding environment, and also providing convenience for subsequent construction operations.

[0016] Preferably, two extension seats are fixed at the bottom of the connecting belt, and linkage blocks are provided inside the two extension seats, and a rotating shaft is fixed inside the linkage block, and both sides of the rotating shaft are plugged into the two extension seats. Two reinforcement plates are fixed between the linkage block and the support plate, and two extension seats are fixed at the bottom of the connecting belt, and linkage blocks are provided inside the extension seats, and the rotating shaft is fixed inside the linkage block, and both sides of the rotating shaft are plugged into the extension seats. Two reinforcement plates are fixed between the linkage block and the support plate, so that the connection between the connecting belt and the support plate is more flexible. At the same time, the reinforcement plate can enhance the connection strength between the linkage block and the support plate, thereby improving the stability and reliability of the entire sealing structure.

[0017] According to a second aspect of the present invention, a method for sealing a karst pile side cave with air expansion is provided, comprising the following steps:

[0018] S1: After drilling, clean the hole, determine the location of the cave, make the airbag bracket according to the size of the steel cage, and weld it outside the steel cage;

[0019] S2: Place the annular airbag on the welded airbag bracket, connect the air guide tube, air pump and inflation tube of corresponding length, and check the air tightness;

[0020] S3: Put the flexible bag on the outside of the steel cage and connect the tying wires on the inner surface of the bag at both ends to the airbag. Then, use the support plate and the connecting belt to make the support plate contact the ground. Then install the support plate through the mounting hole to make the flexible bag more secure.

[0021] S4: Lower the steel cage to the bottom of the hole. After the position is determined, the reinforcement sleeve and the contact plate cooperate with each other to make the air pump and the inflation tube more stable. The air bag is inflated through the air pump and the inflation tube. When the pressure change suddenly increases, it means that the air bag has been pressed against the hole wall. Stop inflation and maintain pressure.

[0022] S5: Start pouring concrete and monitor the concrete liquid level at all times;

[0023] S6: When the concrete liquid level reaches the elevation, stop pouring and use an air pump to completely extract the gas in the airbag to make the airbag in a negative pressure state, tightly attached to the inside of the airbag bracket;

[0024] S7: Refill the concrete left after the air bag shrinks, and turn off the air pump and pull out the inflation tube after the concrete liquid level stabilizes.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention seals karst caves by means of inflation and expansion, thus avoiding leakage during concrete pouring. It can be arranged at fixed points according to the location of the karst cave, reducing material consumption. Furthermore, its flexible structure is suitable for drilling holes of different diameters and has wide applicability. This saves manpower and material resources, greatly improving the success rate of bag pile construction. Furthermore, the flexible bag is made of high-strength geotextile, which can form a reliable sealed space at the location of the karst cave. The top and bottom airbags are composed of annular rubber airbags and metal air nozzles, which are connected to air guide tubes through the air nozzles to achieve inflation and deflation, effectively expanding the volume and supporting the bag.

[0027] 2. The reinforcement structure composed of the reinforcement sleeve, reinforcement rod, support rod, rotating rod and resistance plate on the outer wall of the air pump and the inflation tube of the present invention can stably support the air pump and the inflation tube during use through the cooperation of the rotating mechanism and the limit assembly to prevent them from shaking or shifting, thereby ensuring the smooth progress of the inflation process. At the same time, the top of the flexible cloth bag cooperates with each other through structures such as the connecting belt, support plate, extension seat, linkage block, rotating shaft and reinforcement plate, so that the connection between the cloth bag and the external support is more firmly. At the same time, the rotatable design of the linkage block can adapt to certain deformations and position changes, further enhancing the stability and adaptability of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic structural diagram of the present invention as a whole;

[0029] Figure 2 A cross-sectional view of the present invention as a whole;

[0030] Figure 3 A side view of the present invention as a whole;

[0031] Figure 4 Schematic diagram of the structure of the connecting belt of this method;

[0032] Figure 5 This is a schematic diagram of the structure between the connecting belt and the support plate of the present invention;

[0033] Figure 6 It is a structural schematic diagram of the reinforcement mechanism of the present invention;

[0034] Figure 7 It is a schematic diagram of the structure between the support rod and the rotating rod of the present invention;

[0035] Figure 8 This is a schematic diagram of the structure of the support rod and the rotating rod when they are disassembled;

[0036] Figure 9 It is a structural schematic diagram of the rotating seat of the present invention;

[0037] Figure 10 Flowchart of the method of the present invention.

[0038] Among them: 1. Flexible cloth bag; 2. Top airbag; 3. Bottom airbag; 4. Airbag bracket; 5. Air guide tube; 6. Air pump and inflation tube; 7. Airbag and air nozzle; 8. Connecting belt; 9. Support plate; 10. Steel bar body; 11. Linkage block; 12. Extension seat; 13. Rotating shaft; 14. Reinforcement rod; 15. Support rod; 16. Rotating rod; 17. Resistance plate; 18. Linkage sleeve; 19. Limiting plate; 20. Rotating seat; 21. Insert plate; 22. Limiting rod. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] In the present invention, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0041] See also Figure 1 、 Figure 2 and Figure 3An inflatable expandable pile-side cave sealing structure for karst pile foundations includes a flexible cloth bag 1, a top airbag 2, a bottom airbag 3, an airbag bracket 4, an air guide tube 5, an air pump, and an inflation tube 6. The flexible cloth bag 1 is made of high-strength geotextile and is used to form a sealed space at the cave location. The top airbag 2 and the bottom airbag 3 are composed of an annular airbag and an air nozzle 7. The annular airbag is made of rubber material and is fixed with a metal air nozzle on the upper and lower sides. There are small holes on the side for fixing the cloth bag position. The cloth bag is fixed by a thin wire. The shaped airbag is used to expand the volume and support the bag, the air nozzle is used to connect the air guide tube 5 to complete inflation and deflation, the airbag bracket 4 is made of steel, and consists of a bottom plate and two side guard plates. When in use, it is welded to the steel cage after the position is determined. The position of the airbag is limited in the airbag bracket 4, and the upper and lower guard plates prevent the position of the airbag from changing during the lowering of the steel cage. The air guide tube 5 is made of rubber material and is used to inflate and deflate the airbag. A plurality of evenly distributed steel main bodies 10 are provided inside the flexible bag 1, and the outer walls of the steel main bodies 10 are all wrapped with steel clamps;

[0042] After the air bag 2 and the bottom air bag 3 are inflated, the air bag 2 and the bottom air bag 3 are inflated.

[0043] Please refer to Figure 6 - Figure 9, the outer wall of the air pump and the inflation tube 6 is fixed with a reinforcement sleeve, and reinforcement rods 14 are installed on both sides of the reinforcement sleeve, and a support rod 15 is fixed to one side of the reinforcement rod 14. A rotating rod 16 is hinged on one side of the support rod 15, and a contact plate 17 is installed at the bottom of the rotating rod 16. A rotating mechanism for facilitating the rotation of the rotating rod 16 is provided between the rotating rod 16 and the support rod 15. The rotating mechanism includes a rotating groove opened on one side of the inner side of the support rod 15, and a rotating seat 20 is provided inside the rotating groove. The rotating seat 20 is fixed to the rotating rod 16, and linkage rods are installed on both sides of the rotating seat 20. The two linkage rods The movable rods extend to both sides of the support rod 15 and are fixed with linkage sleeves 18. A limiting assembly for limiting the rotating seat 20 is provided on the top of the support rod 15. The limiting assembly includes a limiting plate 19 provided on the top of the support rod 15. Extension blocks are fixed on both sides of the limiting plate 19. Bolts are screwed between the two extension blocks and the support rod 15. Two limiting rods 22 are fixed to the bottom of the support rod 15, and plug-ins 21 are fixed on both sides of the bottom of the support rod 15. The two plug-ins 21 are plugged into the linkage sleeve 18. The limiting rod 22 extends to the inside of the rotating groove and is plugged into the rotating seat 20.

[0044] When in use, by rotating the rotating rod 16, the contact plate 17 contacts the surrounding objects, which plays a reinforcing and supporting role for the air pump and the inflation tube 6. At the same time, the limit assembly includes a limit plate 19, an extension block and a bolt to limit the rotating seat 20 to prevent the rotating rod 16 from rotating at will. The plug plate 21 at the bottom of the support rod 15 is plugged into the linkage sleeve 18, and the limit rod 22 extends into the interior of the rotating groove and plugs into the rotating seat 20, further enhancing the stability of the structure.

[0045] During specific use, in the initial state, the air pump and the inflation tube 6 are in a state to be used. The reinforcement sleeve is fixed to the outer wall of the air pump and the inflation tube 6, and the reinforcement rods 14 installed on both sides of the reinforcement sleeve play a preliminary supporting and connecting role, connecting the reinforcement sleeve with the subsequent support rod 15 and other structures. At this time, the rotating rod 16 may be in a retracted or unfolded state, and the limit plate 19 of the limit assembly is in an incompletely fixed position. When it is necessary to reinforce and support the air pump and the inflation tube 6, the operator can apply external force to the rotating rod 16 to rotate it around the hinge point with the support rod 15. The rotating seat 20 is installed in the rotating groove on one side of the inner side of the support rod 15. The rotating seat 20 is fixed to the rotating rod 16. When the rotating rod 16 rotates, it drives the rotating seat 20 to rotate in the rotating groove. At the same time, the two sides of the rotating seat 20 The linkage rod moves with the rotation of the rotating seat 20, and the linkage rod extends to both sides of the support rod 15 and is fixed with a linkage sleeve 18. The linkage sleeve 18 will also change its position with the movement of the linkage rod. After the rotating rod 16 rotates to a suitable position, the contact plate 17 installed at its bottom contacts the surrounding support surface. The contact plate 17 increases the contact area with the support surface, thereby dispersing part of the weight of the air pump and the inflation tube 6 and the possible shaking force to the support surface, thereby stabilizing the air pump and the inflation tube 6.

[0046] Furthermore, in order to prevent the rotating rod 16 from rotating at will during the support process, a limit assembly is needed to limit the rotating seat 20. The operator places the limit plate 19 on the top of the support rod 15, and aligns the extension blocks on both sides of the limit plate 19 with the support rod 15. Then, the extension blocks are screwed to the support rod 15 by bolts. Therefore, the limit plate 19 limits the further rotation of the rotating seat 20 in the rotating groove, ensuring that the rotating rod 16 remains in a suitable supporting position. The plug plate 21 fixed at the bottom of the support rod 15 is plugged into the linkage sleeve 18, and at the same time, the limit rod 22 extends into the inside of the rotating groove and is plugged into the rotating seat 20, constraining the position of the rotating seat 20 and the linkage sleeve 18, thereby enhancing the stability of the entire reinforced structure and preventing the rotating seat 20 from shaking or displacing when subjected to force, thereby ensuring that the contact plate 17 can continuously and stably support the air pump and the inflation tube 6.

[0047] Please also refer to Figure 4 and Figure 5 , the outer wall of the top of the flexible cloth bag 1 is equipped with multiple connecting belts 8, and a support plate 9 is installed at the bottom of one end of the multiple connecting belts 8. A plurality of evenly distributed mounting holes are opened around the bottom of the support plate 9. Two extension seats 12 are fixed to the bottom of the connecting belt 8. A linkage block 11 is provided inside the two extension seats 12. A rotating shaft 13 is fixed inside the linkage block 11. Both sides of the rotating shaft 13 are plugged into the two extension seats 12. Two reinforcement plates are fixed between the linkage block 11 and the support plate 9;

[0048] The top of the flexible bag 1 is fixed with the support plate 9, and the top of the flexible bag 1 is fixed with the support plate 9, so that the top of the flexible bag 1 can be stably fixed.

[0049] The overall working principle of the present invention is:

[0050] The construction workers first need to conduct a detailed survey of the karst cave conditions in the karst area to determine the location, size, shape and other parameters of the caves, so as to provide an accurate basis for the subsequent plugging work. Then, according to the data obtained from the survey, the various components are assembled, and a plurality of evenly distributed steel bars 10 with steel clamps wrapped around the outer wall are installed inside the flexible cloth bag 1 made of high-strength geotextile to enhance the structural strength and stability of the cloth bag. The flexible cloth bag 1 is fixed to the two annular rubber air bags by passing a thin wire through the small holes on the sides of the top air bag 2 and the bottom air bag 3. At the same time, the air bag bracket 4 made of steel is welded to the steel cage according to the predetermined position, and the top air bag 2 and the bottom air bag 3 are placed in the air bag bracket 4. The upper and lower guard plates of the air bag bracket 4 are used to limit the position of the air bag to prevent the position of the air bag from changing during subsequent operations. In addition, a plurality of connecting belts 8 are installed on the top outer wall of the flexible cloth bag 1, and a support plate 9 with a plurality of evenly distributed mounting holes is installed at the bottom of one end of the connecting belt 8. A linkage block 11 is set in the two extension seats 12 at the bottom of the connecting belt 8. The rotating shaft 13 connects it with the extension seat 12, and then fixes the linkage block 11 to the support plate 9 with a reinforcement plate, fixes the reinforcement sleeve on the outer wall of the air pump and the inflation tube 6, installs reinforcement rods 14 on both sides of the reinforcement sleeve, and fixes the support rod 15 on one side of the reinforcement rod 14, hinges the rotating rod 16 on one side of the support rod 15, and installs the contact plate 17 at the bottom of the rotating rod 16. The assembled steel cage with the blocking structure is slowly lowered into the pile hole until it reaches the location of the cave. In this process, the airbag bracket 4 plays a key role, and its upper and lower guard plates can This effectively prevents the top and bottom airbags 2 and 3 from shifting position due to factors such as shaking and collision during the lowering of the steel cage, ensuring that the airbags accurately reach the predetermined blocking position. Once the steel cage and blocking structure have accurately reached the cave, the construction workers use a rubber air guide 5 to connect the metal air nozzles 7 on the top and bottom airbags 2 and 3 to the air pump and inflation tube 6. The air pump is then activated, and the gas generated by the air pump is transported through the inflation tube 6 and air guide 5 to the interior of the annular airbags of the top and bottom airbags 2 and 3. As gas is continuously injected, the volume of the annular airbags gradually expands.Since the flexible cloth bag 1 has been fixed to the airbag by a thin wire, the expansion of the airbag will drive the flexible cloth bag 1 to expand outward. During this process, the steel body 10 and the steel clamp inside the flexible cloth bag 1 further enhance the structural strength of the cloth bag, so that it can better withstand the tension and pressure during the expansion process, ensuring that the cloth bag will not break or deform during the expansion process. As the airbag continues to expand, the flexible cloth bag 1 gradually forms a complete sealed space at the cave position, isolating the cave from the surrounding environment. During the inflation process of the airbag, in order to ensure the stability of the air pump and the inflation tube 6, it is necessary to reinforce them. By rotating the rotating rod 16 and utilizing the rotating mechanism between the rotating rod 16 and the support rod 15, namely the rotating groove and the rotating seat 20, the contact plate 17 at the bottom of the rotating rod 16 is in close contact with the ground or other supporting objects. The linkage rods on both sides of the rotating seat 20 extend to both sides of the support rod 15 and are fixed with linkage sleeves 18. When the rotating rod 16 is rotated, the linkage sleeve 18 will move accordingly. At the same time, the plug plates 21 on both sides of the bottom of the support rod 15 are inserted into the linkage sleeve 18. The limiting rod 22 at the bottom of the support rod 15 extends into the interior of the rotating groove and is plugged into the rotating seat 20 to further enhance the stability of the structure. Then, the limiting assembly is used to limit the rotating seat 20, and the limiting plate 19 is placed on the top of the support rod 15. The extension blocks on both sides of the limiting plate 19 are screwed and fixed to the support rod 15 by bolts to prevent the rotating rod 16 from rotating accidentally during the inflation process, ensuring that the air pump and the inflation tube 6 remain stable throughout the inflation process. When the top air bag 2 and the bottom air bag 3 are fully expanded and the flexible cloth bag 1 forms a reliable sealed space at the cave position, the air pump is stopped to complete the blocking of the cave. At this time, the blocking structure can effectively prevent groundwater, mud and other materials in the cave from entering the pile hole, providing a stable environment for subsequent pile foundation construction. If the blocking structure needs to be dismantled or adjusted during the subsequent construction process, the air pump and the inflation tube 6 can be connected again, the air nozzle 7 can be opened, and the gas in the top air bag 2 and the bottom air bag 3 can be released to shrink the air bag, and the flexible cloth bag 1 will return to its original state, making it convenient for the next step of operation.

[0051] A method for sealing a karst pile foundation's side caverns by inflating and expanding the pile, comprising the following steps:

[0052] S1: After drilling, clean the hole, determine the location of the cave, make the airbag bracket 4 according to the size of the steel cage, and weld it outside the steel cage;

[0053] S2: Put the annular airbag on the welded airbag bracket 4, connect the air guide tube 5 of corresponding length and the air pump and inflation tube 6, and check the air tightness;

[0054] S3: Put the flexible bag 1 on the outside of the steel cage, and connect the tying wires on the inner surface of both ends of the bag to the airbag. Then, use the support plate 9 and the connecting belt 8 to cooperate with each other to make the support plate 9 contact with the ground. Then install the support plate 9 through the mounting hole to make the flexible bag 1 more secure.

[0055] S4: Lower the steel cage to the bottom of the hole. After the position is determined, the reinforcement sleeve and the contact plate 17 cooperate with each other to make the air pump and the inflation tube 6 more stable. The air bag is inflated through the air pump and the inflation tube 6. When the pressure change suddenly increases, it means that the air bag has been pressed against the hole wall. Stop inflation and maintain pressure.

[0056] S5: Start pouring concrete and monitor the concrete liquid level at all times;

[0057] S6: When the concrete liquid level reaches the elevation, the pouring is stopped, and the air in the airbag is completely extracted using an air pump to make the airbag in a negative pressure state, so that the airbag is tightly attached to the inside of the airbag bracket 4;

[0058] S7: Refill the concrete left after the air bag shrinks, and turn off the air pump and pull out the inflation tube after the concrete liquid level stabilizes.

[0059] Anything not described in the present invention can be achieved by adopting or drawing on existing technologies.

[0060] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0061] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An inflatable expandable pile-side cave plugging structure for a karst pile foundation, comprising a flexible cloth bag (1), a top airbag (2), a bottom airbag (3), an airbag bracket (4), an air guide tube (5), an air pump and an inflation tube (6), characterized in that: The flexible bag (1) includes a high-strength geotextile and is used to form a sealed space at the location of the cave. The top airbag (2) and the bottom airbag (3) are composed of an annular airbag and an air nozzle (7). The annular airbag is made of rubber material, and metal air nozzles are fixed on the upper and lower sides. There are small holes on the side for fixing the position of the bag. The bag is fixed by a thin wire. The annular airbag is used to expand the volume to support the bag. The air nozzle is used to connect the air guide tube (5) to complete inflation and deflation. Inflation and deflation are achieved by connecting the air guide tube through the air nozzle, which can effectively expand the volume to support the bag. The airbag bracket (4) is made of steel and includes a bottom plate and two side guard plates. When in use, the position is determined and then welded to the steel cage. The position of the airbag is limited in the airbag bracket (4). The upper and lower guard plates prevent the position of the airbag from changing during the lowering of the steel cage. The air guide tube (5) is made of rubber material and is used for inflating and deflating the airbag. At the same time, the flexible bag is made of high-strength geotextile and can form a reliable sealed space at the cave location.

2. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 1, characterized in that: A plurality of evenly distributed steel bar bodies (10) are arranged inside the flexible cloth bag (1), and the outer walls of the steel bar bodies (10) are each wrapped with a steel bar clamp.

3. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 1, characterized in that: A reinforcement sleeve is fixed to the outer wall of the air pump and the inflation tube (6), and reinforcement rods (14) are installed on both sides of the reinforcement sleeve. A support rod (15) is fixed to one side of the reinforcement rod (14), and a rotating rod (16) is hinged to one side of the support rod (15). A contact plate (17) is installed at the bottom of the rotating rod (16).

4. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 3, characterized in that: A rotating mechanism is provided between the rotating rod (16) and the supporting rod (15) to facilitate the rotation of the rotating rod (16). The rotating mechanism comprises a rotating groove provided on one side of the interior of the supporting rod (15). A rotating seat (20) is provided inside the rotating groove. The rotating seat (20) is fixed to the rotating rod (16).

5. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 4, characterized in that: Linkage rods are installed on both sides of the rotating seat (20), and the two linkage rods extend to both sides of the support rod (15) and are fixed with linkage sleeves (18). A limiting component for limiting the rotating seat (20) is provided on the top of the support rod (15).

6. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 5, characterized in that: The limiting assembly comprises a limiting plate (19) arranged on the top of the support rod (15), and extension blocks are fixed on both sides of the limiting plate (19), and bolts are screwed between the two extension blocks and the support rod (15).

7. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 6, characterized in that: Two limiting rods (22) are fixed to the bottom of the support rod (15), and plug plates (21) are fixed to both sides of the bottom of the support rod (15), and the two plug plates (21) are plugged into the linkage sleeve (18). The limiting rod (22) extends to the inside of the rotating groove and is plugged into the rotating seat (20).

8. An inflatable expandable pile-side cave plugging structure for karst pile foundation according to any one of claims 1 to 7, characterized in that: A plurality of connecting belts (8) are installed on the outer wall of the top of the flexible cloth bag (1), a support plate (9) is installed at the bottom of one end of the plurality of connecting belts (8), and a plurality of evenly distributed mounting holes are opened around the bottom of the support plate (9).

9. The pneumatic expandable pile-side cave plugging structure for karst pile foundation according to claim 8, characterized in that: Two extension seats (12) are fixed at the bottom of the connecting belt (8), and linkage blocks (11) are provided inside the two extension seats (12). A rotating shaft (13) is fixed inside the linkage block (11), and both sides of the rotating shaft (13) are plugged into the two extension seats (12). Two reinforcement plates are fixed between the linkage block (11) and the support plate (9).

10. A method for sealing a karst pile foundation cave by pneumatic expansion according to claims 1-9, characterized in that: The following steps are involved: S1: After the hole is formed, clean the hole, determine the location of the cave, make the airbag bracket (4) according to the size of the steel cage, and weld it outside the steel cage; S2: Place the annular airbag on the welded airbag bracket (4), connect the air guide tube (5) of corresponding length and the air pump and inflation tube (6), and check the air tightness; S3: The flexible cloth bag (1) is placed outside the steel cage, and the tying wires on the inner surfaces of both ends of the cloth bag are connected to the airbags. Subsequently, the support plate (9) and the connecting belt (8) are used to cooperate with each other so that the support plate (9) contacts the ground, and the support plate (9) is then installed through the installation hole to make the flexible cloth bag (1) more secure. S4: Lower the steel cage to the bottom of the hole. After the position is determined, the reinforcement sleeve and the contact plate (17) cooperate with each other to make the air pump and the inflation tube (6) more stable. The air bag is inflated through the air pump and the inflation tube (6). When the pressure change suddenly increases, it means that the air bag has been pressed against the hole wall. Stop inflation and maintain pressure. S5: Start pouring concrete and monitor the concrete liquid level at all times; S6: When the concrete liquid level reaches the elevation, the pouring is stopped, and the air in the airbag is completely extracted using an air pump to make the airbag in a negative pressure state, so that the airbag is closely attached to the inside of the airbag bracket (4); S7: Refill the concrete left after the air bag shrinks, and turn off the air pump and pull out the inflation tube after the concrete liquid level stabilizes.

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