Bunching assembly type open caisson structure, device for sinking open caisson and construction method

Abstract

The invention discloses a bunched assembly type open caisson structure, a device for sinking an open caisson and a construction method. The bunched assembly type open caisson structure comprises a plurality of quadrilateral hollow pipes. The side wall, connected with another adjacent quadrilateral hollow pipe, of each quadrilateral hollow pipe is provided with a plurality of steel strand penetrating holes in the length direction, and the steel strand penetrating holes are perpendicular to the length direction. The device for sinking the open caisson comprises a drill rod and a power device, a drill rod head is arranged at the lower end of the drill rod, and a shear fork type telescopic structure and an electromagnetic connection driving device are arranged between the drill rod and the drill rod head, so that the drill rod head can be driven by the electromagnetic connection driving device to reciprocate along the axis of the drill rod. During sinking, water sprayed from the drill rod head is stirred with the soil body cut by the telescopic spiral blade to form slurry while the telescopic spiral blade forming the scissor-type telescopic structure rotationally cuts the soil body, and then the slurry is discharged to the ground through the slurry discharging pipe. The occupied space of the ground during the construction period is reduced, and the open caisson structure in any plane shape is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of caisson construction, and particularly to a bundled prefabricated caisson structure, a device for caisson sinking, and a construction method. Background Art

[0002] Caisson is a common deep foundation construction method, which is widely used in projects such as bridge piers and underground structures. The traditional caisson construction method usually requires fabricating the caisson structure on the ground and then sinking it to the design elevation by its own weight or auxiliary equipment. The current caisson construction methods have the following problems:

[0003] 1. During the caisson construction period, the entire plane projection area needs to be occupied, with a large occupied space and a long time.

[0004] 2. The plane shape of the caisson structure is usually a symmetric shape (such as circular or rectangular), which is difficult to meet the requirements of complex plane shapes.

[0005] 3. From a planar perspective, the caisson sinks as a whole, with a large single excavation volume and a great impact on the surrounding environment.

[0006] 4. The caisson sinks as a whole, with poor adaptability to complex geological conditions. The caisson structure may encounter multiple different types of soil layers simultaneously, which is likely to cause inclination.

[0007] Therefore, how to occupy a small site during the sinking construction, have a small impact on the surrounding environment, have strong adaptability to complex geological conditions, and can also realize the combination of multiple vertical hollow structures to form any shape without additionally increasing the difficulty of caisson construction and environmental impact has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0008] In view of the above-mentioned defects of the prior art, the present invention provides a bundled prefabricated caisson structure, a device for caisson sinking, and a construction method, and the achieved purpose is to decompose the caisson structure into multiple vertical hollow components and bundle them into a whole, which can reduce the ground occupation space during the construction period, realize the caisson structure with any plane shape, and meet the complex geological conditions and diverse underground space requirements.

[0009] To achieve the above purpose, the present invention discloses a bundled prefabricated caisson structure, including a plurality of quadrilateral hollow tubes, and among the plurality of quadrilateral hollow tubes, there are a plurality of quadrilateral hollow standard tubes and a plurality of quadrilateral hollow operation tubes;

[0010] Each of the quadrilateral hollow operation tubes is a quadrilateral hollow tube with a plane size larger than that of the quadrilateral hollow standard tube;

[0011] A plurality of quadrilateral hollow standard tubes are sequentially spliced horizontally to form a caisson side wall unit;

[0012] Each of the quadrilateral hollow operating pipes is simultaneously connected to two, three or four of the caisson side wall units to form a ninety-degree bend, a T-shaped node or a cross-shaped node;

[0013] Every two adjacent quadrilateral hollow tubes are connected by pre-buried T-shaped rails and pre-buried C-shaped grooves arranged on both sides of the connecting surface and matching each other to form a movable pair, so that they can move back and forth relative to each other in the vertical direction;

[0014] The side wall of each of the quadrilateral hollow tubes connected to another adjacent quadrilateral hollow tube is provided with a plurality of steel strand through holes perpendicular to the length direction along the length direction;

[0015] All the quadrilateral hollow operating tubes of each caisson side wall unit and all the steel strand through holes on the corresponding two quadrilateral hollow standard tubes form a plurality of mutually parallel steel strand through passages along the length direction;

[0016] Each of the steel strand threading channels extends from a corresponding one of the quadrilateral hollow operating tubes to another of the quadrilateral hollow operating tubes;

[0017] Both ends of each steel strand passed through the steel strand passing channel are anchored in the corresponding two quadrilateral hollow operating tubes.

[0018] Preferably, during construction, each of the steel strand penetration holes is provided with a rubber plug for waterproof sealing.

[0019] More preferably, all the rubber plugs located on the same side wall of the same quadrilateral hollow tube are connected by a same rope, and before inserting the steel strands, all the rubber plugs are taken out by dragging the corresponding ropes.

[0020] Preferably, the cross section of each of the quadrilateral hollow tubes is trapezoidal or fan-shaped.

[0021] The present invention also provides a device for sinking a caisson, comprising a hollow drill rod and a power device for driving the hollow drill rod to rotate;

[0022] The upper end of the drill rod is provided with a guide device, the lower end is provided with a drill rod head, and a scissor-type telescopic structure and an electromagnetic connection driving device are provided between the drill rod head, so that the drill rod head can be driven by the electromagnetic connection driving device to reciprocate along the axis of the drill rod;

[0023] The scissor-type telescopic structure comprises four telescopic spiral blades which are hinged in pairs;

[0024] The electromagnetic connection driving device comprises two parts, which are respectively arranged on the drill rod and the drill rod head, and are attracted or separated by electromagnetic force;

[0025] The drill pipe, the drill pipe head, and the electromagnetic connection driving device are all of hollow structures, and a grouting pipe and a slurry discharge pipe are arranged inside.

[0026] Preferably, the drill pipe comprises a plurality of segments connected end to end.

[0027] Preferably, the articulated positions of four retractable spiral blades that are articulated pairwise can be adjusted.

[0028] Preferably, inside each of the quadrilateral hollow pipes, a plurality of convex structures are arranged in the depth range of 1 to 2 times the side length of the quadrilateral hollow pipe near the bottom.

[0029] The present invention also provides a construction method for a bundled and assembled open caisson structure, comprising the following steps:

[0030] Step 1: Place the device for the sinking of the open caisson on the ground. The electromagnetic connection driving device keeps the drill pipe and the drill pipe head in a suction state, so that the size of the corresponding horizontal plane of the retractable spiral blade extends to the maximum unfolded state;

[0031] Step 2: Sleeve the quadrilateral hollow pipe to be sunk outside the drill pipe, and fix it to the device for the sinking of the open caisson through a fixing device;

[0032] Step 3: Start the power device to drive the drill pipe to rotate, driving the retractable spiral blade to rotate and cut the soil;

[0033] Step 4: While the retractable spiral blade rotates to cut the soil, inject clear water into the drill pipe through the grouting pipe, and make the clear water spray out from the drill pipe head to stir with the soil cut by the retractable spiral blade to form slurry, and then discharge the slurry to the ground through the slurry discharge pipe until the excavation and tunneling are completed;

[0034] While carrying out the excavation and tunneling, sink the quadrilateral hollow pipe until the designed elevation;

[0035] Step 5: After the quadrilateral hollow pipe reaches the designed elevation, inject concrete or cement slurry into the bottom of the quadrilateral hollow pipe through the grouting pipe to displace the slurry within the depth range of 1 to 2 times the side length of the quadrilateral hollow pipe at the bottom,

[0036] At the same time, switch the electromagnetic connection driving device to a state where the drill pipe and the drill pipe head are separated, so that the retractable spiral blade shrinks to the minimum contracted state in the horizontal dimension;

[0037] Finally, lift the device for the sinking of the open caisson out of the quadrilateral hollow pipe;

[0038] Step 6: After the concrete or cement slurry at the bottom of the quadrilateral hollow pipe solidifies, suck out the residual slurry inside the quadrilateral hollow pipe and clean the inside of the quadrilateral hollow pipe;

[0039] Repeat Steps 1 to 6 to complete the sinking of all the quadrilateral hollow pipes;

[0040] Step 7: Inside each quadrilateral hollow operation pipe, pass the steel strand through the steel strand threading channel formed by the steel strand perforations at multiple same elevations to another quadrilateral hollow operation pipe, and fix the steel strand through the anchor. After all the steel strands are threaded and prestressed construction is carried out, all the quadrilateral hollow pipes are combined into an integral structure by the prestressed steel strand bundles;

[0041] Step 8: Pour concrete into all the quadrilateral hollow pipes to the top surface to form an integral open caisson structure;

[0042] Step 9: Excavate soil inside the integral open caisson structure. After excavating to the design elevation, pour blinding concrete to form the required underground space.

[0043] Preferably, in Step 9, during the soil excavation process, the deformation and stability of the integral open caisson structure are monitored in real time to ensure construction safety.

[0044] Advantages of the present invention:

[0045] By decomposing the open caisson structure into multiple vertical hollow components and combining them into an integral whole, the present invention can reduce the ground occupation space during the construction period and realize open caisson structures with any planar shape, meeting the requirements of complex geological conditions and diverse underground space.

[0046] The following will further illustrate the concept, specific structure and technical effects of the present invention with reference to the drawings to fully understand the purpose, features and effects of the present invention. Brief Description of the Drawings

[0047] Figure 1 Shows a cross-sectional structural schematic diagram of the bundled prefabricated open caisson structure in an embodiment of the present invention.

[0048] Figure 2 Shows a cross-sectional structural schematic diagram of the quadrilateral hollow standard pipe in an embodiment of the present invention.

[0049] Figure 3 Shows a structural schematic diagram of the maximum separation distance between the lower drill pipe and the drill bit of the device for open caisson sinking in an embodiment of the present invention.

[0050] Figure 4 Shows a structural schematic diagram of the separation or suction process between the lower drill pipe and the drill bit of the device for open caisson sinking in an embodiment of the present invention.

[0051] Figure 5 Schematic structural diagram showing the lower drill pipe of the device for caisson sinking in an embodiment of the present invention being sucked and adhered tightly to the drill pipe head.

[0052] Figure 6 Schematic cross-sectional structural diagram of the drill pipe in an embodiment of the present invention.

[0053] Figure 7 Schematic structural diagram of one end of the drill pipe provided with an electromagnetic connection driving device in an embodiment of the present invention.

[0054] Figure 8 Schematic state diagram of a quadrilateral hollow pipe during sinking in an embodiment of the present invention. Detailed implementation manners

[0055] Embodiment

[0056] As Figure 1 and Figure 2 As shown, the bundled and assembled caisson structure includes a plurality of quadrilateral hollow pipes 1, and the plurality of quadrilateral hollow pipes 1 include a plurality of quadrilateral hollow standard pipes 11 and a plurality of quadrilateral hollow operation pipes 12;

[0057] Each quadrilateral hollow operation pipe 12 is a quadrilateral hollow pipe 1 with a planar size larger than that of the quadrilateral hollow standard pipe 11;

[0058] A plurality of quadrilateral hollow standard pipes 11 are sequentially spliced horizontally to form a caisson side wall unit;

[0059] Each quadrilateral hollow operation pipe 12 is simultaneously connected to two, three or four caisson side wall units to form a 90-degree bend angle, a T-shaped node or a cross-shaped node;

[0060] Between every two adjacent quadrilateral hollow pipes 1, including between every two adjacent quadrilateral hollow operation pipes 12, between every two adjacent quadrilateral hollow standard pipes 11, and between an adjacent quadrilateral hollow operation pipe 12 and quadrilateral hollow standard pipe 11, they are connected by pre-embedded T-shaped rails 21 and pre-embedded C-shaped grooves 22 arranged on both sides of the joint surface and matching with each other to form a moving pair connection, and can move relatively reciprocally in the vertical direction;

[0061] On the side wall of each quadrilateral hollow pipe 1 connected to an adjacent quadrilateral hollow pipe 1, a plurality of steel strand perforations 23 perpendicular to the length direction are provided along the length direction;

[0062] All the steel strand perforations 23 on all the quadrilateral hollow operation pipes 12 of each caisson side wall unit and the corresponding two quadrilateral hollow standard pipes 11 form a plurality of mutually parallel steel strand threading channels along the length direction;

[0063] Each strand threading channel extends from one corresponding quadrilateral hollow operation pipe 12 to another quadrilateral hollow operation pipe 12.

[0064] Both ends of each strand threaded in the strand threading channel are anchored in the corresponding two quadrilateral hollow operation pipes 12.

[0065] In the present invention, the caisson structure is decomposed into multiple quadrilateral hollow pipes 1. The quadrilateral hollow pipes 1 are divided into quadrilateral hollow standard pipes 11 and quadrilateral hollow operation pipes 12. The width of the quadrilateral hollow standard pipe 11 is the same as the wall thickness of the bundled and assembled caisson structure. The size of the quadrilateral hollow operation pipe 12 is larger than that of the quadrilateral hollow standard pipe 11 enough for the operator to enter and operate inside.

[0066] In some embodiments, during construction, each strand perforation 23 is provided with a rubber plug 24 for waterproof plugging.

[0067] In some embodiments, all the rubber plugs 24 located on the same side wall of the same quadrilateral hollow pipe 1 are connected by the same rope 25. Before threading the strand, all the rubber plugs 24 are taken out by dragging and pulling the corresponding rope 25.

[0068] In some embodiments, the cross-section of each quadrilateral hollow pipe 1 is trapezoidal or fan-shaped.

[0069] In practical applications, the quadrilateral hollow pipe 1 with a trapezoidal or fan-shaped cross-section can realize a bundled and assembled caisson structure with an arc-shaped profile.

[0070] As Figures 3 to 7 shown, the present invention also provides a device for caisson sinking, including a hollow drill rod 33 and a power device 36 for driving the hollow drill rod 33 to rotate;

[0071] A guiding device 37 is provided at the upper end of the drill rod 33, and a drill bit head 31 is provided at the lower end. A scissor-type telescopic structure and an electromagnetic connection driving device 34 are provided between them, so that the drill bit head 31 can be driven by the electromagnetic connection driving device 34 to reciprocate along the axis of the drill rod 33;

[0072] The scissor-type telescopic structure includes four retractable spiral blades 32 that are hinged to each other in pairs;

[0073] The electromagnetic connection driving device 34 includes parts respectively arranged on the drill rod 33 and the drill bit head 31, and is attracted or separated by electromagnetic force;

[0074] The drill rod 33, the drill bit head 31 and the electromagnetic connection driving device 34 are all hollow structures, and a grouting pipe 38 and a slurry discharge pipe 39 are arranged inside.

[0075] In some embodiments, the drill rod 33 includes a plurality of segments connected end to end.

[0076] In practical applications, the drill pipe 33 including multiple segments connected end to end not only makes the structure and equipment lighter, but also can meet the requirements of low headroom.

[0077] Preferably, the hinged positions of the four retractable spiral blades 32 hinged to each other can be adjusted.

[0078] In practical applications, the ability to adjust the hinged positions can achieve a change in the external expansion size when the retractable spiral blades 32 are in the unfolded state, and can meet the requirements of precast components of different sizes.

[0079] In some embodiments, inside each quadrilateral hollow tube 1, a number of convex structures are provided in the depth range close to the bottom, which is 1 to 2 times the side length of the quadrilateral hollow tube 1.

[0080] In practical applications, providing a number of convex structures inside each quadrilateral hollow tube 1 in the depth range close to the bottom, which is 1 to 2 times the side length of the quadrilateral hollow tube 1, can increase the bonding performance between the quadrilateral hollow tube 1 and the poured concrete or cement slurry.

[0081] As Figure 8 shown, the present invention also provides a construction method for a bundled assembled caisson structure, including the following steps:

[0082] Step 1: Place the device 3 for caisson sinking on the ground, and keep the drill pipe 33 and the drill bit 31 in an attracted state by the electromagnetic connection driving device 34, so that the size of the retractable spiral blade 32 in the corresponding horizontal plane extends to the maximum unfolded state;

[0083] Step 2: Sleeve the quadrilateral hollow tube 1 to be sunk outside the drill pipe 33, and fix it to the device 3 for caisson sinking through the fixing device 35;

[0084] Step 3: Start the power device 36 to drive the drill pipe 33 to rotate, driving the retractable spiral blade 32 to rotate and cut the soil;

[0085] Step 4: While the retractable spiral blade 32 rotates to cut the soil, inject clear water into the drill pipe 33 through the grouting pipe 38, and make the clear water spray out from the drill bit 31 to stir with the soil cut by the retractable spiral blade 32 to form slurry, and then discharge the slurry to the ground through the slurry discharge pipe 39 until the excavation is completed;

[0086] While excavating, sink the quadrilateral hollow tube 1 until the design elevation;

[0087] Step 5. After the quadrilateral hollow pipe 1 reaches the designed elevation, inject concrete or cement slurry into the bottom of the quadrilateral hollow pipe 1 through the grouting pipe 38 to displace the slurry within the range of a depth of 1 to 2 times the side length of the quadrilateral hollow pipe 1 at the bottom,

[0088] Meanwhile, switch the electromagnetic connection driving device 34 to the state where the drill pipe 33 and the drill bit 31 are separated, and retract the retractable spiral blade 32 to the retracted state with the minimum horizontal dimension;

[0089] Finally, lift the device 3 for the sinking of the open caisson from inside the quadrilateral hollow pipe 1;

[0090] Step 6. After the concrete or cement slurry at the bottom of the quadrilateral hollow pipe 1 solidifies, suck out the residual slurry inside the quadrilateral hollow pipe 1 and clean the inside of the quadrilateral hollow pipe 1;

[0091] Repeat Steps 1 to 6 to complete the sinking of all the quadrilateral hollow pipes 1;

[0092] Step 7. Inside each quadrilateral hollow operation pipe 12, thread the steel strands through the steel strand threading channels formed by a plurality of steel strand perforations 23 at the same elevation to another quadrilateral hollow operation pipe 12, and fix the steel strands through the anchor fittings. After all the steel strands are threaded and tensioned, all the quadrilateral hollow pipes 1 are combined into an integral structure by the prestressed steel strand bundles;

[0093] Step 8. Pour concrete into all the quadrilateral hollow pipes 1 to the top surface to form an integral open caisson structure;

[0094] Step 9. Excavate soil inside the integral open caisson structure. After reaching the designed elevation, pour the blinding concrete to form the required underground space.

[0095] In some embodiments, in Step 9, during the soil excavation process, the deformation and stability of the integral open caisson structure are monitored in real time to ensure construction safety.

[0096] During construction, each quadrilateral hollow pipe 1 is successively sunk to the designed elevation.

[0097] The quadrilateral hollow pipe 1 is prefabricated or fabricated on-site and has sufficient strength and stiffness to withstand the loads during the pressing-in process.

[0098] The quadrilateral hollow pipe 1 is sunk by combining spiral soil excavation with static pressure. After sinking in place, a certain thickness of blinding concrete is poured inside the component.

[0099] Then, prestressed steel strands are used for bundling;

[0100] After all the quadrilateral hollow pipes 1 are pressed into the soil, the prestressed steel strands are operated in the quadrilateral hollow operation pipe 12, and the discrete quadrilateral hollow pipes 1 are combined into an integral structure by the prestressed steel strand bundles. The arrangement and tension of the prestressed steel strands are adjusted according to the design requirements to ensure the stability and strength of the integral structure.

[0101] Then, concrete is poured;

[0102] Concrete is poured into the bundled quadrilateral hollow pipe 1 to the top surface to form an integral open caisson structure;

[0103] During the concrete pouring process, it is necessary to ensure the compactness and uniformity to improve the bearing capacity and durability of the structure.

[0104] Finally, the soil is excavated to form an underground space: the soil is excavated inside the integral open caisson structure, and after reaching the design elevation, the bottom sealing concrete is poured to form the required underground space.

[0105] During the soil excavation process, it is necessary to monitor the deformation and stability of the open caisson structure in real time to ensure the construction safety.

[0106] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations according to the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the protection scope determined by the claims.

Claims

1. A bundled assembled caisson structure, comprising a plurality of quadrilateral hollow tubes (1); characterized in that: The plurality of quadrilateral hollow tubes (1) include a plurality of quadrilateral hollow standard tubes (11) and a plurality of quadrilateral hollow operating tubes (12); Each of the quadrilateral hollow operating tubes (12) is a quadrilateral hollow tube (1) having a larger plane size than the quadrilateral hollow standard tube (11); A plurality of quadrilateral hollow standard pipes (11) are sequentially and transversely spliced ​​to form a caisson side wall unit; Each of the quadrilateral hollow operating pipes (12) is simultaneously connected to two, three or four of the caisson side wall units to form a ninety-degree bend, a T-shaped node or a cross-shaped node; Every two adjacent quadrilateral hollow tubes (1) are connected by a movable pair formed by pre-buried T-shaped rails (21) and pre-buried C-shaped grooves (22) arranged on both sides of the connecting surface and matching each other, so as to be able to reciprocate relative to each other in the vertical direction; The side wall of each of the quadrilateral hollow tubes (1) connected to another adjacent quadrilateral hollow tube (1) is provided with a plurality of steel strand through holes (23) perpendicular to the length direction along the length direction; All of the quadrilateral hollow operating tubes (12) of each caisson side wall unit and all of the steel strand through holes (23) on the corresponding two quadrilateral hollow standard tubes (11) form a plurality of mutually parallel steel strand through passages along the length direction; Each of the steel strand threading channels extends from a corresponding one of the quadrilateral hollow operating tubes (12) to another of the quadrilateral hollow operating tubes (12); Both ends of each steel strand passed through the steel strand passing channel are anchored in the corresponding two quadrilateral hollow operating tubes (12).

2. The bundled assembled caisson structure according to claim 1 is characterized in that: During construction, each of the steel strand through holes (23) is provided with a rubber plug (24) for waterproof sealing.

3. The bundled assembled caisson structure according to claim 2 is characterized in that: All the rubber plugs (24) located on the same side wall of the same quadrilateral hollow tube (1) are connected by a same rope (25). Before the steel strand is inserted, all the rubber plugs (24) are taken out by pulling the corresponding rope (25).

4. The bundled assembled caisson structure according to claim 1 is characterized in that: The cross section of each of the quadrilateral hollow tubes (1) is trapezoidal or fan-shaped.

5. A device for sinking a caisson, characterized in that: It comprises a hollow drill rod (33) and a power device (36) for driving the hollow drill rod (33) to rotate; The upper end of the drill rod (33) is provided with a guide device (37), the lower end is provided with a drill rod head (31), and a scissor-type telescopic structure and an electromagnetic connection drive device (34) are provided between the drill rod head (31), so that the drill rod head (31) can be driven by the electromagnetic connection drive device (34) to reciprocate along the axis of the drill rod (33); The scissor-type telescopic structure comprises four telescopic spiral blades (32) which are hinged to each other. The electromagnetic connection driving device (34) comprises two parts, which are respectively arranged on the drill rod (33) and the drill rod head (31), and are attracted or separated by electromagnetic force; The drill rod (33), the drill rod head (31) and the electromagnetic connection drive device (34) are all hollow structures, and a grouting pipe (38) and a grouting pipe (39) are arranged inside.

6. The device for sinking a caisson according to claim 5, characterized in that: The drill pipe (33) comprises a plurality of segments connected end to end.

7. The device for sinking a caisson according to claim 5, characterized in that: The hinge positions of the four retractable spiral blades (32) which are hinged to each other can be adjusted.

8. The bundled assembled caisson structure according to claim 1 is characterized in that: Inside each of the quadrilateral hollow tubes (1), a plurality of protruding structures are arranged near the bottom at a depth of 1 to 2 times the side length of the quadrilateral hollow tube (1).

9. A construction method for a bundled assembled caisson structure, characterized in that: The steps include: Step 1: placing a device (3) for sinking a caisson on the ground, and an electromagnetic connection driving device (34) keeps the drill rod (33) and the drill rod head (31) in an engaged state, so that the size of the corresponding horizontal plane of the retractable spiral blade (32) is extended to the maximum expansion state; Step 2: The quadrilateral hollow tube (1) to be sunk is placed outside the drill rod (33) and fixed to the device (3) for sinking the caisson by a fixing device (35); Step 3, starting the power device (36) to drive the drill rod (33) to rotate, thereby driving the retractable spiral blade (32) to rotate and cut the soil; Step 4: while the retractable spiral blade (32) is rotating and cutting the soil, clean water is injected into the drill rod (33) through the grouting pipe (38), and the clean water is sprayed out from the drill rod head (31) and mixed with the soil cut by the retractable spiral blade (32) to form mud, and then the mud is discharged to the ground through the slurry discharge pipe (39) until the excavation is completed; While digging, sinking the quadrilateral hollow pipe (1) to the designed elevation; Step 5: After the quadrilateral hollow tube (1) reaches the designed elevation, concrete or cement slurry is injected into the bottom of the quadrilateral hollow tube (1) through the grouting pipe (38) to replace the mud in the bottom within a depth range of 1 to 2 times the side length of the quadrilateral hollow tube (1). At the same time, the electromagnetic connection driving device (34) is switched to a state in which the drill rod (33) and the drill rod head (31) are separated, so that the retractable spiral blade (32) is retracted to a retracted state in which the horizontal dimension is the smallest; Finally, the device (3) for sinking the caisson is lifted out of the quadrilateral hollow tube (1); Step 6, after the concrete or cement slurry at the bottom of the quadrilateral hollow tube (1) solidifies, the residual slurry in the quadrilateral hollow tube (1) is sucked out, and the inside of the quadrilateral hollow tube (1) is cleaned; Repeat steps 1 to 6 to complete the sinking of all the quadrilateral hollow tubes (1); Step 7, in each quadrilateral hollow operating tube (12), the steel strands are passed through a steel strand passing channel formed by a plurality of steel strand passing holes (23) of the same elevation into another quadrilateral hollow operating tube (12), and the steel strands are fixed by anchors. After all the steel strands are passed through and prestressed, all the quadrilateral hollow tubes (1) are bundled together to form an integral structure by the prestressed steel strands. Step 8, pouring concrete into all the quadrilateral hollow tubes (1) to the top surface to form an integral caisson structure; Step 9: dig in the integral caisson structure, and pour bottom sealing concrete after digging to the designed elevation to form the required underground space.

10. The construction method of the bundled assembled caisson structure according to claim 9, characterized in that: In step 9, the deformation and stability of the overall caisson structure are monitored in real time during the excavation process to ensure construction safety.

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