Construction technology and construction equipment for clay body super deep digging pile

Abstract

This invention discloses a construction process and equipment for ultra-deep pile excavation in cohesive soil, including excavation equipment, a grouting unit for injecting slurry, and at least one set of clamping units for holding a wire mesh, all mounted on the excavation equipment. The grouting unit includes a grouting frame rotatably connected to the power arm of the excavation equipment, a mixing component for stirring the slurry mounted on the grouting frame, and a moving component for driving the mixing component upward / downward. The mixing component has a slurry inlet connected to its slurry inlet and an outlet connected to the grouting component via a pipe. The clamping units include a fixing frame fixedly connected to the grouting frame and at least one set of clamping components mounted on the fixing frame for holding the slurry. This invention can solve the problem of collapse during ultra-deep pile hole excavation in complex environments, excavating and reinforcing deep pile holes in complex geographical environments, and providing equipment for rapid reinforcement, thus improving work efficiency.

Description

Technical Field

[0001] This invention belongs to the field of ultra-deep foundation engineering technology in complex environments, specifically relating to an ultra-deep pile excavation construction process and its construction equipment in cohesive soil. Background Technology

[0002] Deep-hole piles are a foundation engineering technique used in construction projects, primarily to increase soil bearing capacity or stabilize soil. They are formed by drilling holes in the ground and injecting concrete. The construction process of deep-hole piles typically includes the following steps:

[0003] Drilling: Drilling holes underground using drilling rigs or other drilling equipment. The diameter and depth of the borehole depend on the specific project requirements.

[0004] Clean the bottom of the borehole: Clean the bottom of the borehole to remove loose soil and gravel, ensuring the stability of the borehole bottom.

[0005] Reinforcing steel installation: Reinforcing steel is installed inside the hole to increase the load-bearing capacity of the deep-hole pile.

[0006] Concrete pouring: Concrete is poured into the hole to fill it completely. Pumping equipment is typically used to deliver the concrete into the hole.

[0007] Curing: After the concrete has hardened, it needs to be cured to ensure its strength and stability.

[0008] Currently, in the first step of drilling, especially when drilling deep holes in complex geographical environments such as deserts, rock layers, and hilly areas, the holes are very prone to collapse, leading to pile hole failure or insufficient bearing capacity of the hole wall, failing to meet the stress requirements of the pile hole. Summary of the Invention

[0009] The purpose of this invention is to provide a construction process and equipment for ultra-deep excavation of piles in cohesive soil, which solves the problem that when drilling deep holes in complex geographical environments, such as deserts, rock layers, and hilly areas, the holes are very prone to collapse, leading to pile hole failure, or the bearing capacity of the hole wall is insufficient, failing to meet the stress requirements of the pile hole.

[0010] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0011] A construction process for ultra-deep pile excavation in cohesive soil, characterized by the following steps:

[0012] S1) Measuring soil void ratio: Measure the specific gravity and density of the soil, and calculate the void ratio using the following formula:

[0013]

[0014] Where e is the void ratio of the cohesive soil itself, Gs is the specific gravity of the cohesive soil, and ρ α It is the density of cohesive soil; where G s The formula is as follows:

[0015] Where, m s For soil mass, V s For the volume of soil, ρ wl The density of water;

[0016] Based on the porosity ratio, they are classified as follows:

[0017] A1: e < 0.6: The soil layer is dense;

[0018] A2: 0.6 < e < 0.75: The soil layer is slightly dense;

[0019] A3: e>0.75: Loose soil layer;

[0020] S2) Determine the first excavation depth X1: Excavate using excavation equipment and mark the positioning points:

[0021] X1 = m s / ((e+1)ρ α )x(πR 2 ρ wl )

[0022] Where e is 0.75 and R is the diameter of the pile hole;

[0023] The actual excavation depth is X1-ζ, where ζ is the safety factor error, taken as 0.5-1 meter;

[0024] S3) Inserting a needle mesh: Inserting a needle mesh into the inner wall of the bottom of the hole to form a circumferential needle mesh layer around the bottom of the hole;

[0025] S4) Segmented spraying: Insert the nozzle into the needle mesh layer 2-5mm, inject the mud mixture, the injection time is 2-3 seconds, the grouting pressure is 10-100 kg / cm², after the injection is completed, remove the nozzle and move it down 30-50mm, continue to inject in segments until the entire needle mesh layer is covered;

[0026] S5) Apply adhesive: Apply adhesive to other hole wall areas without needle mesh layer spraying;

[0027] S6) Remove mud and water: Remove the mud and water and mud slurry from the bottom of the hole;

[0028] S7) Complete multiple excavations to the specified depth: Repeat steps S2)-S5), and the hardening degree of the mud needs to reach more than 50% before each excavation.

[0029] Furthermore, S3) is placed in the needle mesh, and the needle length Lr There are three specifications, which are selected according to the following formula:

[0030] Lr = (X + e) / R

[0031] Where, X is the hole depth, e is the void ratio, and R is the pile hole diameter;

[0032] When Lr < 2, the needle length is selected as 600 mm;

[0033] When 2 < Lr < 3, the needle length is selected as 400 mm;

[0034] When 3 < Lr, the needle length is selected as 200 mm.

[0035] Furthermore, in the S4) layered slurry spraying, the slurry ratio is in parts by weight and includes: water: 50 - 100 parts, calcium-based bentonite: 5 - 10 parts, 10% concentration sodium hydroxide solution: 0.1 - 0.2 parts, NaCl: 0.1 - 0.5 parts, iron-chromium salt: 0.15 - 0.2 parts, Na-CMC: 0.2 parts, sodium carbonate: 0.1 - 0.3 parts.

[0036] Furthermore, in the S6) binder spraying, the binder ratio is in parts by weight and includes: water: 80 - 100 parts, starch: 20 - 30 parts (where raw starch accounts for 75 - 85% and cooked starch accounts for 15 - 25%), caustic soda: 0.4 - 0.8 parts, borax: 0.27 - 0.32 parts.

[0037] A construction equipment for super-deep excavation piles in cohesive soil, the excavation equipment (1) includes a slurry spraying part (2) for injecting slurry and at least one clamping part (3) for clamping the needle mesh (6);

[0038] The slurry spraying part (2) includes a slurry spraying frame (21) rotatably connected to the power arm (12) of the excavation equipment (1), a stirring part (23) installed on the slurry spraying frame (21) for stirring the slurry, and a moving part (22) for driving the stirring part (23) to move up / down. The input port of the stirring part (23) is connected to the slurry, and the output port is connected to the slurry spraying part (24) through a pipeline;

[0039] The clamping part (3) includes a fixed frame (31) fixedly connected to the slurry spraying frame (21), at least one clamping part (32) installed on the fixed frame (31) for clamping, and a buckle part (33) for buckling the needle mesh (6);

[0040] The excavation equipment (1) is also provided with a hydraulic part (11) for driving the slurry spraying frame (21) to rotate. One end of the hydraulic part (11) is fixed on the power arm (12), and the output end is hinged to the slurry spraying frame (21).

[0041] Furthermore, the excavation equipment (1) is also equipped with a pushing part (4) for pushing the needle net (6) into the soil and a sliding part (5) for driving the shotcrete part (2) and the pushing part (4) to move;

[0042] The sliding part (5) includes a sliding member (51) that slides on the fixed frame (31), a slide rail (52) that accommodates the sliding member (51) and a second hydraulic unit (53) that pushes the sliding member (51) to slide. The shotcrete member (24) is fixed inside the sliding member (51). When the sliding member (51) slides, it drives the shotcrete member (24) to move.

[0043] The pushing part (4) includes a pushing member (42) for pushing the needle mesh (6) and a control member (41) for controlling the movement of the pushing member (42), the control member (41) being fixedly connected to the sliding member (51);

[0044] The control unit (41) includes an air source (413) for providing power, an elastic element (412) for resetting, and a control block (411) for accommodating the elastic element (412). When the air source (413) is introduced, high-pressure gas pushes the pusher (42) forward, and the elastic element (412) resets the pusher (42).

[0045] Furthermore, the clamping member (32) includes at least two sets of clamping jaws (325) and a first hydraulic element (321) for driving the clamping jaws (325) to clamp. The output end of the first hydraulic element (321) is fixedly connected to the driving member (322). The driving member (322) is hinged to the gear element (323) through the connecting rod (324). The clamping jaws (325) are also provided with teeth that mesh with the gear element (323). The clamping jaws (325) are provided with textures to increase friction. When the first hydraulic element (321) drives the driving member (322) to move, it can drive the gear element (323) to drive the clamping jaws (325) to clamp.

[0046] Furthermore, the moving part (22) includes a lead screw (222), a first electric element (221) that drives the lead screw (222) to rotate, and at least two sets of moving blocks (223) that move up / down on the lead screw (222), and the stirring part (23) is fixed on the moving blocks (223);

[0047] The stirring component (23) includes a stirring tank (232), a screw (233) disposed inside the stirring tank (232) for stirring, and a second electric component (231) for driving the screw (233) to rotate.

[0048] Furthermore, the needle net (6) includes a net frame (62) and a number of long needles (61) arranged on the net frame (62) and folded by folding members (612); the long needles (61) are provided with barbs (611) around their body to facilitate soil stabilization.

[0049] Furthermore, the latching member (33) includes a claw (311) rotatably connected to the clamping member (32) and a pneumatic element (332) for driving the claw (311) to rotate. The claw (311) is used to hold the needle net (6), and the output end of the pneumatic element (332) is hinged to the claw (311).

[0050] The beneficial effects of this invention are:

[0051] 1. This invention, through a construction process of first measuring and then excavating in sections, and covering with a mesh layer, can ensure the quality completion of excavation work for ultra-deep pile holes in complex environments, and solves the problem of complex and deep pile holes being prone to collapse.

[0052] 2. The construction equipment of the present invention has a slurry spraying part and a clamping part for holding the needle mesh installed on the head. After the needle mesh is installed, slurry can be sprayed directly, which improves work efficiency.

[0053] 3. This invention optimizes the mud mix ratio, shortens the mud hardening time, and reduces construction time.

[0054] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0055] Figure 1 A schematic diagram of the construction equipment for reinforcing ultra-deep pile holes;

[0056] Figure 2 This is a schematic diagram of the clamping part structure;

[0057] Figure 3 This is a schematic diagram of the stirring component structure;

[0058] Figure 4 This is a schematic diagram of the clamping component structure;

[0059] Figure 5 This is a schematic diagram of the sliding part structure;

[0060] Figure 6 This is a schematic diagram of the control component structure;

[0061] Figure 7 This is a cross-sectional view of the mixing component;

[0062] Figure 8 This is a schematic diagram of the fastener structure;

[0063] Figure 9 This is a diagram of a long needle.

[0064] Figure 10 for Figure 9 A magnified view of part A;

[0065] Figure 11 This is a schematic diagram of the construction process.

[0066] Explanation of reference numerals in the attached figures:

[0067] 1. Excavating equipment; 11. Hydraulic components; 12. Power arm; 2. Shotcrete unit; 21. Shotcrete frame; 22. Moving parts; 221. First electric component; 222. Lead screw; 223. Moving block; 23. Mixing component; 231. Second electric component; 232. Mixing tank; 24. Shotcrete component; 3. Clamping unit; 31. Fixing frame; 32. Clamping component; 321. First hydraulic component; 322. Drive component; 32 3. Gear components; 324. Connecting rod; 325. Gripper; 33. Buckle; 331. Gripper; 332. Pneumatic components; 4. Pushing part; 41. Control component; 411. Control block; 412. Elastic element; 413. Air source; 5. Sliding part; 51. Sliding component; 52. Slide rail; 53. Second hydraulic unit; 6. Needle net; 61. Long needle; 611. Barb; 612. Folding component; 62. Net frame. Detailed Implementation

[0068] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention. Specific implementation examples:

[0070] like Figures 1 to 8 The diagram shows an ultra-deep pile excavation equipment for cohesive soil, including an excavation device 1 and a slurry spraying part 2 and a set of clamping parts 3 for clamping a needle mesh 6 installed on the excavation device 1; specifically, the needle mesh (6) includes a mesh frame (62) and a number of long needles (61) arranged on the mesh frame (62) and folded by folding parts (612); the long needles (61) are provided with barbs (611) around their periphery to facilitate soil stabilization.

[0071] The shotcrete unit 2 includes a shotcrete frame 21 rotatably connected to the power arm 12 of the excavating equipment 1, a mixing element 23 mounted on the shotcrete frame 21 for mixing mud, and a moving element 22 that drives the mixing element 23 to move upward / downward. The mixing element 23 has a mud inlet connected to its inlet and a shotcrete element 24 connected to its outlet via a pipe. Specifically, the moving element 22 includes a lead screw 222, a first electric component 221 that drives the lead screw 222 to rotate, and two sets of moving blocks 223 that move upward / downward on the lead screw 222. The mixing element 23 is fixed to the moving blocks 223. Specifically, the mixing element 23 includes a mixing tank 232, a screw 233 disposed inside the mixing tank 232 for mixing, and a second electric component 231 that drives the screw 233 to rotate.

[0072] The clamping part (3) includes a fixed frame (31) fixedly connected to the shotcrete frame (21) and at least one set of clamping members (32) installed on the fixed frame (31) for clamping and a snap fastener (33) for fastening the needle net (6); specifically, the clamping member 32 includes two sets of clamping jaws 325 and a first hydraulic element 321 for driving the jaws 325 to clamp. The output end of the first hydraulic element 321 is fixedly connected to the driving member 322. The driving member 322 is hinged to the gear element 323 through the connecting rod 324. The jaws 325 are also provided with teeth that mesh with the gear element 323. When the first hydraulic element 321 drives the driving member 322 to move, it can drive the gear element 323 to drive the jaws 325 to clamp. Specifically, the latching member (33) includes a claw (311) rotatably connected to the clamping member (32) and a pneumatic element (332) for driving the claw (311) to rotate. The claw (311) is used to hold the needle net (6), and the output end of the pneumatic element (332) is hinged to the claw (311).

[0073] The excavating equipment 1 is also equipped with a hydraulic component 11 for rotating the shotcrete frame 21. One end of the hydraulic component 11 is fixed to the power arm 12, and the output end is hinged to the shotcrete frame 21. Specifically, the excavating equipment 1 is also equipped with a pushing part 4 for pushing the needle mesh 6 into the soil and a sliding part 5 for moving the shotcrete part 2 and the pushing part 4.

[0074] The sliding part 5 includes a sliding member 51 that slides on the fixed frame 31, a slide rail 52 that accommodates the sliding member 51, and a second hydraulic unit 53 that pushes the sliding member 51 to slide. The shotcrete member 24 is fixed inside the sliding member 51. When the sliding member 51 slides, it drives the shotcrete member 24 to move.

[0075] The pushing part 4 includes a pushing member 42 for pushing the needle mesh 6 and a control member 41 for controlling the movement of the pushing member 42. The control member 41 is fixedly connected to the sliding member 51. Specifically, the control member 41 includes an air source 413 for providing power, an elastic element 412 for resetting, and a control block 411 for accommodating the elastic element 412. When the air source 413 is introduced, high-pressure gas pushes the pushing member 42 forward, and the elastic element 412 resets the pushing member 42.

[0076] Suppose a project requires excavating pile holes 50 meters deep and 2 meters in diameter:

[0077] A construction technique for ultra-deep pile excavation in cohesive soil includes the following steps:

[0078] S1) Measuring soil void ratio: Measure the specific gravity and density of the soil. The diameter of the borehole is 20cm, and the depth is 50m. Calculate the void ratio based on the soil layers using the following formula:

[0079]

[0080] Where e is the void ratio of the cohesive soil itself, Gs is the specific gravity of the cohesive soil, and ρ α It is the density of cohesive soil; G s The formula is as follows:

[0081]

[0082] Where, m s For soil mass, V s For the volume of soil, ρ wl The density of water;

[0083] Measurements revealed a 1-meter layer of sand and gravel, a 2-meter layer of clay, and a 1-meter layer of rock in the soil.

[0084] Based on the porosity ratio, they are classified as follows:

[0085] A1: e < 0.6: The soil layer is dense;

[0086] A2: 0.6 < e < 0.75: The soil layer is slightly dense;

[0087] A3: e>0.75: Loose soil layer;

[0088] S2) Determine the first excavation depth X1: Excavate using excavation equipment and mark the positioning points:

[0089] X1=ms / ((e+1)ρα)x(πR2ρwl)

[0090] Where e is 0.75 and R is the diameter of the pile hole;

[0091] The actual excavation depth is X1 - ζ, where ζ is the safety factor error, taking 0.5 - 1 meter. The obtained values are 7m, 10m, 13m, 15m, and 5m respectively;

[0092] S3) Insert the needle net: Insert the needle net into the inner wall of the hole bottom to form a whole-body needle net layer on the inner periphery of the hole bottom; specifically, in the process of inserting the needle net, the needle length L r has three specifications and is selected according to the following formula:

[0093] Lr = (X + e) / R

[0094] where X is the hole depth, e is the void ratio, and R is the pile hole diameter;

[0095] When Lr < 2, the needle length is selected as 600mm;

[0096] When 2 < Lr < 3, the needle length is selected as 400mm;

[0097] When 3 < Lr, the needle length is selected as 200mm

[0098] S4) Spray grout in segments: Insert the nozzle into the needle net layer by 2 - 5mm, inject the mud mixture, the injection time is 2 - 3 seconds, the grouting pressure is 10 - 100 kg / cm², after the injection is completed, remove the nozzle and move down 30 - 50mm, and continue to inject in segments until all the needle net layers are covered; specifically, the equipment used in the S3 and S4 steps is the construction equipment mentioned above. Specifically, the mud ratio in the S4 layered grouting is: water: 100 parts, calcium-based bentonite: 10 parts, 10% concentration caustic soda solution: 0.1 part, NaCl: 0.1 part, ferrochrome salt: 0.15 part, Na-CMC: 0.2 part, sodium carbonate: 0.1 part;

[0099] S5) Pump out the muddy water: Pump out all the muddy water and mud at the hole bottom;

[0100] S6) Spray the binder: Spray the binder on other hole wall areas without needle net layer grouting; specifically,

[0101] The binder ratio is in parts by weight and includes: water: 80 - ១០០ parts, starch: 20 - 30 parts (where raw starch accounts for 75 - 85%, and cooked starch accounts for 15 - 25%), caustic soda: 0.4 - 0.8 part, borax: 0.27 - 0.32 part. [[ID=ģģ]] [[ID=ģ4]]

[0102] S7) Complete multiple excavations to the specified depth: Repeat steps S2)-S5), and based on the data calculated in S2, sequentially excavate to depths of 10m, 13m, 15m, etc. After each excavation, it is necessary to cycle through the installation of the mesh reinforcement, shotcreting, and dewatering. Specifically, in step S6, which involves excavating again and installing the mesh reinforcement, the mud must reach a hardening degree of over 50% before excavating again. At a set temperature of 30 degrees Celsius, this requires at least 55 hours of hardening. The following are the hardening times tested for mud with different compositions.

[0103] Experimental data:

[0104] Control group 1:

[0105] Ingredients: Water: 100 parts, calcium-based bentonite: 10 parts, 10% caustic soda solution: 0.1 parts, NaCl: 0.1 parts;

[0106] Average temperature: 5-10°C; Curing time for 25% completion: 70 hours; Curing time for 50% completion: 160 hours

[0107] Average temperature: 10-20°C; Curing time for 25% completion: 45 hours; Curing time for 50% completion: 110 hours

[0108] Average temperature: 20-30°C; Curing time for 25% completion: 30 hours; Curing time for 50% completion: 63 hours

[0109] Average temperature: 30-40°C; Curing time for 25% completion: 20 hours; Curing time for 50% completion: 43 hours

[0110] Control group 2:

[0111] Ingredients: Water: 100 parts, calcium-based bentonite: 10 parts, 10% caustic soda solution: 0.1 parts, NaCl: 0.1 parts, iron-chromium salt: 0.15 parts, Na-CMC: 0.2 parts;

[0112] Average temperature: 5-10°C; Curing time for 25% completion: 65 hours; Curing time for 50% completion: 155 hours

[0113] Average temperature: 10-20°C; Curing time for 25% completion: 40 hours; Curing time for 50% completion: 105 hours

[0114] Average temperature: 20-30°C; Curing time for 25% completion: 25 hours; Curing time for 50% completion: 60 hours

[0115] Average temperature: 30-40°C; Curing time for 25% completion: 15 hours; Curing time for 50% completion: 40 hours

[0116] Control group 3:

[0117] Ingredients: Water: 100 parts, calcium-based bentonite: 10 parts, 10% caustic soda solution: 0.1 parts, NaCl: 0.1 parts, iron-chromium salt: 0.15 parts, sodium carbonate: 0.1 parts;

[0118] Average temperature: 5-10°C; Curing time for 25% completion: 63 hours; Curing time for 50% completion: 154 hours

[0119] Average temperature: 10-20°C; Curing time for 25% completion: 39 hours; Curing time for 50% completion: 100 hours

[0120] Average temperature: 20-30°C; Curing time for 25% completion: 23 hours; Curing time for 50% completion: 59 hours

[0121] Average temperature: 30-40°C; Curing time for 25% completion: 13 hours; Curing time for 50% completion: 37 hours

[0122] Control group 4:

[0123] Ingredients: Water: 100 parts, calcium-based bentonite: 10 parts, 10% caustic soda solution: 0.1 parts, NaCl: 0.1 parts, iron-chromium salt: 0.15 parts, Na-CMC: 0.2 parts, sodium carbonate: 0.1 parts;

[0124] Average temperature: 5-10°C; Curing time for 25% completion: 55 hours; Curing time for 50% completion: 128 hours

[0125] Average temperature: 10-20°C; Curing time for 25% completion: 36 hours; Curing time for 50% completion: 90 hours

[0126] Average temperature: 20-30°C; Curing time for 25% completion: 20 hours; Curing time for 50% completion: 55 hours

[0127] Average temperature: 30-40°C; Curing time for 25%: 10 hours; Curing time for 50%: 36 hours

[0128] The comparison shows that control group 4 has the shortest hardening time and can be considered the optimal solution.

[0129] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A construction equipment for ultra-deep pile excavation in cohesive soil, characterized in that... The excavation equipment (1) includes a spraying section (2) for spraying mud and at least one set of clamping sections (3) for clamping the needle mesh (6); the excavation equipment (1) is also equipped with a pushing section (4) for pushing the needle mesh (6) into the soil and a sliding section (5) for moving the spraying section (2) and the pushing section (4). The shotcrete unit (2) includes a shotcrete frame (21) rotatably connected to the power arm (12) of the excavating equipment (1), a mixing component (23) mounted on the shotcrete frame (21) for mixing mud, and a moving component (22) for driving the mixing component (23) to move up / down. The mixing component (23) has a mud inlet connected to its inlet and a shotcrete component (24) connected to its outlet via a pipe. The excavating equipment (1) is also provided with a hydraulic component (11) for pushing the shotcrete frame (21) to rotate. One end of the hydraulic component (11) is fixed to the power arm (12). The output end is hinged to the shotcrete frame (21); the moving part (22) includes a lead screw (222) and a first electric component (221) that drives the lead screw (222) to rotate and at least two sets of moving blocks (223) that move up / down on the lead screw (222); the stirring part (23) is fixed on the moving block (223); the stirring part (23) includes a stirring tank (232) and a screw (233) disposed inside the stirring tank (232) for stirring and a second electric component (231) that drives the screw (233) to rotate. The clamping part (3) includes a fixed frame (31) fixedly connected to the shotcrete frame (21) and at least one set of clamping members (32) mounted on the fixed frame (31) for clamping and a snap-fit ​​member (33) for fastening the needle net (6); the clamping member (32) includes at least two sets of clamping jaws (325) for clamping and a first hydraulic element (321) for driving the clamping jaws (325) to clamp, the output end of the first hydraulic element (321) is fixedly connected to a driving member (322), the driving member (322) is hinged to a gear element (323) through a connecting rod (324), and the clamping jaws (325) It is also provided with a tooth that meshes with the gear element (323), and the gripper (325) is provided with a texture to increase friction. When the first hydraulic element (321) drives the drive member (322) to move, it can drive the gear element (323) to drive the gripper (325) to clamp. The buckle (33) includes a gripper (311) rotatably connected to the clamping member (32) and a pneumatic element (332) that drives the gripper (311) to rotate. The gripper (311) is used to hold the needle net (6), and the output end of the pneumatic element (332) is hinged to the gripper (311). The sliding part (5) includes a sliding member (51) that slides on the fixed frame (31), a slide rail (52) that accommodates the sliding member (51) and a second hydraulic unit (53) that pushes the sliding member (51) to slide. The shotcrete member (24) is fixed inside the sliding member (51). When the sliding member (51) slides, it drives the shotcrete member (24) to move. The pushing part (4) includes a pushing member (42) for pushing the needle mesh (6) and a control member (41) for controlling the movement of the pushing member (42). The control member (41) is fixedly connected to the sliding member (51). The control member (41) includes an air source (413) for providing power, an elastic element (412) for resetting, and a control block (411) for accommodating the elastic element (412). When the air source (413) is introduced, high-pressure gas pushes the pushing member (42) forward, and the elastic element (412) resets the pushing member (42). The needle net (6) includes a net frame (62) and a number of long needles (61) arranged on the net frame (62) and folded by folding members (612); the long needles (61) are provided with barbs (611) around their sides to facilitate soil stabilization.

2. The ultra-deep pile excavation equipment for cohesive soil as described in claim 1, characterized in that, It also includes the following construction techniques, specifically: S1) Measuring soil void ratio: Measure the specific gravity and density of the soil, and calculate the void ratio using the following formula: ； Wherein, e is the void ratio of the cohesive soil itself, Gs is the specific gravity of the cohesive soil, p α is the density of the cohesive soil; wherein G s The formula is as follows: ； where m s is the mass of soil, V s is the volume of soil, p wl is the density of water; Based on the porosity ratio, they are classified as follows: A1: e < 0.6: The soil layer is compacted; A2: 0.6 < e < 0.75: The soil layer is slightly dense; A3:e> 0.75: Loose soil layer; S2) Determine the first excavation depth X1: Excavate using excavation equipment and mark the positioning points: X1=m s / ((e+1)ρ α )x(πR 2 r wl ) Where e is 0.75, R is the diameter of the pile hole; the actual excavation depth is X1-ζ; ζ is the safety factor error, which is 0.5~1 meter; S3) Inserting a needle mesh: Inserting a needle mesh into the inner wall of the bottom of the hole to form a circumferential needle mesh layer around the bottom of the hole; S4) Segmented grouting: Insert the nozzle into the needle mesh layer 2-5mm, inject the mud mixture, the injection time is 2-3 seconds, the grouting pressure is 10-100 kg / cm², after the injection is completed, remove the nozzle and move it down 30-50mm, continue to inject in segments until the entire needle mesh layer is covered; S6) Apply adhesive: Apply adhesive to other hole wall areas without needle mesh layer spraying; S7) Remove mud and water: Remove the mud and water and mud slurry from the bottom of the hole; S8) Complete multiple excavations to the specified depth: Repeat steps 2-5, and the hardening degree of the mud needs to reach more than 50% before each excavation.

3. The ultra-deep pile excavation equipment for cohesive soil as described in claim 2, characterized in that: In step 3, the needle is inserted into the needle mesh, and the needle length L r There are three specifications, selected according to the following formula: L r =(X+e) / R Where X is the hole depth, e is the void ratio, and R is the pile hole diameter; When L r When < 2, the needle length should be 600mm; When 2 < L r When the needle length is less than 3, a length of 400mm should be selected. When 3 < L r When choosing a needle length, select 200mm.

4. The ultra-deep pile excavation equipment for cohesive soil as described in claim 2, characterized in that: The mud mix ratio in step 4, layered spraying, by weight, includes: water: 50-100 parts, calcium-based bentonite: 5-10 parts, 10% concentration caustic soda solution: 0.1-0.2 parts, NaCl: 0.1-0.5 parts, iron-chromium salt: 0.15-0.2 parts, Na-CMC: 0.2 parts, and sodium carbonate: 0.1-0.3 parts.

5. The ultra-deep pile excavation equipment for cohesive soil as described in claim 2, characterized in that: The adhesive formulation in step 6, when spraying the adhesive, comprises the following components by weight: water: 80-100 parts, starch: 20-30 parts, caustic soda: 0.4-0.8 parts, and borax: 0.27-0.32 parts.

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