Sinking construction system and construction method for barrel-shaped foundation

Abstract

The invention belongs to the field of offshore wind turbine bucket foundations, and provides a sinking construction system and method for a bucket foundation, and the system comprises a monitoring system, a vacuum pump system, a hydraulic system, a leveling system and a vacuum pump suction system; multi-system cooperative intelligent work is achieved, and the barrel-shaped foundation hoisting work efficiency is improved; the method plays an important role in the barrel-shaped foundation penetration stage, especially the suction penetration stage, the reasonable and correct posture of a barrel body of the barrel-shaped foundation in the penetration process is ensured through real-time monitoring and dynamic leveling, and the problem of control over the sinking construction posture of the barrel-shaped foundation is solved; after penetration installation of the barrel-shaped foundation is completed, automatic separation and rapid recovery of the installation device are achieved, and the installation construction efficiency of the barrel-shaped foundation is greatly improved.

Description

Technical Field

[0001] The invention belongs to the field of offshore wind turbine barrel foundations, and in particular relates to a barrel foundation sinking construction system and a construction method. Background Art

[0002] Marine wind energy has great development prospects because of its high annual usage hours and no waste of land resources. However, compared with onshore wind power generation equipment, the environment of offshore wind power generation equipment is more complex, and the funds, manpower and material resources required will also increase further, which is mainly reflected in the high construction cost of wind turbines and foundation structures and the high cost of later operation and maintenance. Therefore, as a barrel foundation with simple construction, economical and reliable, it has gradually attracted the attention of engineers and scholars and has great development prospects. The installation methods of barrel foundations are mainly divided into suction sinking, pressure sinking and vibration sinking, among which suction sinking is more common. Suction sinking is to use a vacuum pump to form a pressure difference between the inside and outside of the barrel to achieve sinking. It is worth noting that since the foundation installation process is significantly affected by the wind and wave environment and geological conditions, the sinking posture of the barrel foundation will inevitably tilt during the installation process. This phenomenon is particularly prominent in the installation process of large-size single barrel foundations, and the posture control during the sinking of the barrel foundation is the decisive factor for the success or failure of the construction. Therefore, it is necessary to study and propose a refined barrel foundation sinking construction technology method.

[0003] On the other hand, the recovery of the installation tools for suction sinking is a more difficult problem in the construction, which is mainly divided into two parts, namely the recovery of the vacuum pump and the recovery of the sinking auxiliary device (such as the guide frame during hoisting, etc.). Among them, the recovery of the vacuum pump requires the arrangement of professionals to dive to the installation position of the barrel foundation to separate the connecting pipes between the vacuum pump and the barrel foundation and the barrel foundation interface. The construction operation is complicated and has certain risks. Therefore, it is necessary to propose a simpler and safer way to recover the equipment for the barrel foundation sinking construction. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a sinking construction system and a construction method of a barrel foundation to solve the problems in the prior art. The technical solution adopted by the present invention is:

[0005] A sinking construction system for a barrel foundation, comprising a hydraulic system 3, a leveling system 4 and a vacuum pump suction system 5;

[0006] The hydraulic system 3 comprises a bracket and a boom, the boom is mounted on the bracket, and the leveling system 4 is arranged at the lifting end of the boom;

[0007] The leveling system 4 comprises a suction claw 4.1, a vacuum pump 4.2, a telescopic rod 4.3, and an annular fixing frame; the annular fixing frame is sleeved on the barrel-shaped foundation, a plurality of the suction claws 4.1 are installed on the annular fixing frame, and the plurality of the suction claws 4.1 are respectively connected to the telescopic rod 4.3, the top of the telescopic rod 4.3 is rotatably connected to the annular top frame, and the annular top frame is fixedly connected to the lifting end of the boom, and the telescopic rod 4.3 is used to drive the suction claw 4.1 to push the barrel-shaped foundation to deflect, thereby realizing the leveling function;

[0008] The vacuum pump 4.2 is installed on the annular top frame, and the vacuum pump 4.2 is connected to the interior of the barrel foundation through the vacuum pump suction system 5.

[0009] Furthermore, the vacuum pump suction system 5 comprises a vacuum pump interface housing 5.1, an inner ring 5.2, a sealing ring 5.3, an air extraction conduit 5.4, a compression piston 5.5, a traction rope 5.6 and a spring 5.7;

[0010] The vacuum pump interface housing 5.1 is sleeved on the barrel-shaped foundation, and the inner ring 5.2 is slidably arranged on the inner wall surface of the vacuum pump interface housing 5.1, and the inner ring 5.2 is located between the vacuum pump interface housing 5.1 and the barrel-shaped foundation;

[0011] The sealing ring 5.3 is arranged on the inner side of the end of the inner ring 5.2. The sealing ring 5.3 is located at one end of the barrel-shaped foundation. The other end of the barrel-shaped foundation is connected to the vacuum pump 4.2 through the exhaust duct 5.4. The exhaust duct 5.4 is connected in parallel with a side tube. The compression piston 5.5 is arranged in the side tube. The compression piston 5.5 is fixedly connected to the inner ring 5.2 through the traction rope 5.6. A stopper is fixedly arranged on the inner wall surface of the vacuum pump interface shell 5.1. The spring 5.7 is arranged between the stopper and the inner ring 5.2. The spring 5.7 is sleeved on the traction rope 5.6.

[0012] The present invention can use the monitoring system 1 to monitor the key parameters during the installation of the barrel foundation and the recovery of the hoist, and accurately control the vacuum pump 4.2 and the hydraulic system 3 according to the monitored parameters. Among them, the sinking rate of the barrel foundation can be effectively controlled by the vacuum pump system 4.2, and the hydraulic system 3 can reasonably distribute and deliver the appropriate pressure for each specific mechanical device (such as the telescopic operation of the boom, etc.).

[0013] A sinking construction method for a barrel foundation comprises the following steps:

[0014] The first step is ship anchoring: after the barrel foundation is transported to the construction site, the crane ship arrives at the designated position;

[0015] Step 2: Foundation hoisting: connect the suction claw 4.1 to the barrel foundation, and connect the vacuum pump 4.2 to the top of the barrel foundation through the vacuum duct 5.4 and the vacuum interface;

[0016] The third step is foundation penetration: it is divided into two stages, self-sinking into the mud and negative pressure penetration;

[0017] Self-sinking stage: When the bucket foundation is lowered to 2m from the mud surface, the posture of the bucket foundation is corrected by the suction claw 4.1. After confirmation, the bucket foundation is lowered until it self-sinks into the mud;

[0018] When the barrel foundation cannot continue to sink by its own weight, it will enter the negative pressure penetration stage after being left still for 3 hours: the vacuum pump 4.2 will evacuate the air and the monitoring system 1 will monitor the real-time pressure difference between the inside and outside of the barrel foundation and the sinking posture, so that the barrel foundation can be smoothly penetrated under the action of a reasonable pressure difference between the inside and outside;

[0019] Step 4: Device recovery:

[0020] After the barrel foundation is penetrated into place, various parameters of the barrel foundation are re-measured. After the parameters are verified to meet the design requirements, the vacuum pump 4.2 and the suction claw 4.1 are separated from the barrel foundation.

[0021] Furthermore, the required negative pressure in the bucket foundation is calculated by the following method:

[0022] When the bucket foundation is sunk and placed, the sinking resistance at the penetration depth z is:

[0023] R=R side +R tip =A wall ·α·s u +(N c ·s u,tip +γ'·z)A tip (1)

[0024] Among them, A wall A is the sum of the contact areas between the inner and outer walls of the barrel and the soil; tip is the base bottom area; s u is the average direct shear undrained shear strength at penetration depth; α is the friction coefficient of the barrel wall; s u,tip is the average undrained shear strength of bucket end triaxial compression, triaxial tension and direct shear; γ' is the effective weight of soil; N c is the bearing capacity coefficient under plane strain conditions; z is the penetration depth;

[0025] The negative pressure required for the bucket foundation to sink is:

[0026] Δu n =(R-W') / A c (2)

[0027] Where: W' is the basic floating weight; A c It is the negative pressure loading plane area in the barrel;

[0028] The maximum allowable negative pressure for sinking is:

[0029] Δu a =N c ·s u,tip +A in ·α·s u / A c (3)

[0030] Among them, A in It is the contact area between the inner wall of the barrel and the soil.

[0031] The present invention has the following beneficial effects:

[0032] (1) The multi-system of the present invention works in a coordinated and intelligent manner to improve the efficiency of barrel foundation hoisting;

[0033] (2) The present invention plays an important role in the penetration of bucket foundations, especially in the suction penetration stage. Through real-time monitoring and dynamic leveling, the reasonable and correct posture of the bucket body of the bucket foundation during the penetration process is ensured, thus solving the problem of posture control during the sinking construction of the bucket foundation.

[0034] (3) The present invention realizes automatic separation and rapid recovery of the installation device after the barrel foundation is installed, which greatly improves the installation and construction efficiency of the barrel foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure;

[0036] Figure 2 This is a schematic diagram of the leveling system;

[0037] Figure 3 It is a schematic diagram of the vacuum pump suction system;

[0038] Figure 4 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0039] The following will be combined with the embodiments of the present invention Figure 1-Figure 4 , the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0040] A sinking construction system for a barrel foundation, comprising a monitoring system 1, a vacuum pump system 2, a hydraulic system 3, a leveling system 4 and a vacuum pump suction system 5;

[0041] The hydraulic system 3 comprises a bracket and a boom, the boom is mounted on the bracket, and the leveling system 4 is arranged at the lifting end of the boom;

[0042] The leveling system 4 includes a suction claw 4.1, a vacuum pump 4.2, a telescopic rod 4.3, and an annular fixing frame; the annular fixing frame is sleeved on the barrel-shaped foundation, and a plurality of the suction claws 4.1 are installed on the annular fixing frame, and the plurality of suction claws 4.1 are respectively connected to the telescopic rod 4.3, and the top of the telescopic rod 4.3 is rotatably connected to the annular top frame, and the annular top frame is fixedly connected to the lifting end of the boom, and the telescopic rod 4.3 is used to drive the suction claw 4.1 to push the barrel-shaped foundation to deflect, thereby realizing the leveling function; an electromagnetic suction device 4.1.1 is provided at the end of the suction claw 4.1 for abutting the barrel-shaped foundation.

[0043] The vacuum pump 4.2 is installed on the annular top frame, and the vacuum pump 4.2 is connected to the interior of the barrel foundation through the vacuum pump suction system 5.

[0044] The vacuum pump 4.2 is connected to the vacuum pump system 2 and is used to control the operation of the vacuum pump 4.2. The monitoring system 1, the vacuum pump system 2 and the hydraulic system 3 are installed on the platform of the construction ship. The monitoring system 1 mainly includes posture monitoring, negative pressure monitoring and displacement monitoring. Among them, the posture monitoring target is to monitor the barrel body posture during the whole process of barrel foundation lifting and sinking, which is mainly achieved by the barrel top inclination angle measured by the bidirectional inclinometer; the negative pressure monitoring target is to monitor the pressure difference inside and outside the barrel during the whole process of barrel foundation sinking, which is mainly achieved by the pressure sensor installed inside and outside the barrel top; the displacement monitoring target is to monitor the relative position of the adsorption claw 4.1 and the barrel foundation, which is mainly achieved by the displacement sensor. The telescopic rod 4.3 can be a hydraulic rod, which is connected to the hydraulic system 3 to provide liquid pressure.

[0045] The leveling system 4 refers to a system for dynamically leveling the barrel body posture during the sinking process of the barrel foundation, which is achieved by the coordinated adjustment of the telescopic rod 4.3 and the vacuum pump 4.2's suction speed. The leveling system 4 is intended to ensure that the barrel foundation always maintains an ideal posture during the penetration process to achieve precise positioning and stable penetration. In addition, in order to facilitate the recovery of the device after the barrel foundation has sunk, the suction claw 4.1 is separated from the barrel foundation mainly by cutting off the power supply to the electromagnetic adsorption device 4.1.1 on the suction claw 4.1, so that the suction force of the suction claw 4.1 on the barrel foundation is weakened and the two are separated. The suction claw 4.1 can be movably connected to the annular fixed frame, and the barrel foundation is squeezed by the telescopic rod 4.3, so that one or more of the suction claws 4.1 push the barrel foundation to deflect. The boom is a prior art that can be extended and rotated, and its lifting end is the sling at the end of the sling rope, and the sling is fixedly connected to the annular top frame.

[0046] Furthermore, the vacuum pump suction system 5 comprises a vacuum pump interface housing 5.1, an inner ring 5.2, a sealing ring 5.3, an air extraction conduit 5.4, a compression piston 5.5, a traction rope 5.6 and a spring 5.7;

[0047] The vacuum pump interface housing 5.1 is sleeved on the barrel-shaped foundation, and the inner ring 5.2 is slidably arranged on the inner wall surface of the vacuum pump interface housing 5.1, and the inner ring 5.2 is located between the vacuum pump interface housing 5.1 and the barrel-shaped foundation;

[0048] The sealing ring 5.3 is arranged on the inner side of the end of the inner ring 5.2. The sealing ring 5.3 is located at one end of the barrel-shaped foundation. The other end of the barrel-shaped foundation is connected to the vacuum pump 4.2 through the exhaust duct 5.4. The exhaust duct 5.4 is connected in parallel with a side tube. The compression piston 5.5 is arranged in the side tube. The compression piston 5.5 is fixedly connected to the inner ring 5.2 through the traction rope 5.6. A stopper is fixedly arranged on the inner wall surface of the vacuum pump interface shell 5.1. The spring 5.7 is arranged between the stopper and the inner ring 5.2. The spring 5.7 is sleeved on the traction rope 5.6.

[0049] The vacuum pump 4.2 is connected to the air extraction port of the barrel-shaped foundation. The air extraction port of the barrel-shaped foundation is connected to the vacuum pump 4.2 at the sealing ring 5.3. The sealing ring 5.3 is made of steel sheet and has a certain elasticity. When the vacuum pump is working, the gas and water in the barrel are sucked along the conduit 5.4. When the air extraction conduit 5.4 is exhausted, it will drive the compression piston 5.5 to move. The compression piston 5.5 will drive the traction rope 5.6 and stretch the inner ring 5.2 to move. The spring 5.7 is compressed. When the inner ring 5.2 is pulled backward, the front sealing film will be tightened, thereby achieving the locking function during exhaustion, and realizing the automatic sealing interface of the vacuum pump 4.2 during exhaustion. Among them, the sealing ring 5.3 is connected to the exhaust conduit 5.4. When the vacuum pump 4.2 is working, it will exhaust air from the exhaust conduit 5.4 direction, and the air in the foundation will be extracted through the sealing ring 5.3.

[0050] The vacuum pump is separated from the air extraction port of the barrel-shaped foundation. When the suction penetration operation is completed or the vacuum extraction needs to be stopped for other reasons, the air and water flow speed sucked in the vacuum pump slows down to a standstill, the air extraction at the air extraction duct 5.4 stops, the force required for the piston movement in the compression device 5.5 disappears, and the traction force of the traction rope 5.6 on the inner ring 5.2 disappears. As the traction force disappears, the elastic potential energy of the spring 5.7 is released to push the inner ring 5.2 to rebound, and its constraint on the sealing ring 5.3 disappears, so that the sealing ring 5.3 is loosened from the air extraction port of the barrel-shaped foundation, and then the separation is completed with the lifting of the lifting device. At this time, the vacuum pump 4.2 is automatically separated from the air extraction port on the top of the barrel-shaped foundation when the air extraction is stopped. The vacuum pump interface shell 5.1 only plays the role of wrapping the parts of the air extraction device, and there is no link for removal. The sealing ring 5.3 does not move upward, and the inner ring 5.2 moves upward to compress and tighten the sealing ring 5.3. The inner ring 5.2 and the air extraction duct 5.4 do not interfere with each other.

[0051] A sinking construction method for a barrel foundation comprises the following steps:

[0052] The first step is anchoring the ship: after the barrel foundation is transported to the construction site, the crane ship uses the shipboard GPS and ship positioning software to accurately locate and arrive at the designated position. In order to reduce the safety and inconvenience of lifting caused by the shaking of the hull during lifting, it is necessary to drop anchor and stay in position. The crane ship stays in the top stream at the position of the machine;

[0053] The second step is foundation hoisting: dock the suction claw 4.1 with the barrel foundation, and the six arc-shaped claws are evenly distributed around the top of the barrel. Rubber pads are set inside the claws to increase friction and prevent scratching the barrel wall. In particular, a magnetic suction cup base is set at the hinge between the telescopic rod 4.3 and the suction claw 4.1 to ensure a firm connection between the hoist and the barrel foundation, and ensure dynamic leveling of the posture during the foundation penetration into the seabed and penetration to the predetermined depth. Dock the vacuum pump 4.2 with the vacuum interface, and power on to firmly connect the exhaust duct 5.4 with the vacuum interface on the top of the barrel foundation;

[0054] The third step is foundation penetration: The process of barrel foundation penetration is divided into two stages, namely, self-sinking into the mud and negative pressure penetration. In the self-sinking into the mud stage, when the barrel foundation is lowered to 2m from the mud surface, record the monitoring data of the two-way inclinometer and combine it with the water flow direction and flow rate data, and use the suction claws to dynamically correct the posture of the barrel foundation. After confirmation, continue to lower the barrel foundation to self-sink into the mud until a bucket-soil sealing condition that can be sunk by suction is formed (the depth of penetration into the mud exceeds 2m). In the process of forming the sealing conditions, pay attention to observe the posture of the barrel foundation to avoid excessive tilting of the barrel body. When the level exceeds the standard, adjust the boom and the suction claws until the barrel foundation posture meets the requirements and then lower it again;

[0055] When the barrel foundation cannot continue to sink by its own weight, it is left to stand for another 3 hours to ensure that the seal is formed before entering the negative pressure penetration stage. At this time, the vacuum pump 4.2 is awakened to perform negative pressure sinking. The vacuum pump 4.2 evacuates air and the monitoring system 1 monitors the real-time pressure difference between the inside and outside of the barrel foundation and the sinking posture, so that the barrel foundation can be smoothly penetrated under the action of a reasonable internal and external pressure difference.

[0056] During the penetration and sinking process, special attention should be paid to the control and adjustment of the attitude of the barrel foundation. The sinking attitude of the barrel foundation is recorded by a bidirectional inclinometer. If the horizontal deviation is close to the design requirement limit (2‰), the vacuum pump 4.2 and the leveling system 4 work together according to the actual tilt. The vacuum pump 4.2 will control the pressure difference between the inside and outside of the barrel foundation to a suitable value to slow down the foundation penetration speed. Synchronously, the leveling system 4 will adjust the telescopic rods 4.3 on the six suction claws 4.1 according to the horizontal deviation, so that the horizontality returns to the design threshold, and then the penetration operation is repeated. According to the lowering attitude of the barrel foundation body monitored by the system, the vacuum pump 4.2 and the leveling system 4 are operated in coordination as described above until the horizontality of the sunken barrel foundation reaches the design allowable range. The design allowable range includes: after the foundation sinks, the foundation top rotation angle should be measured, and the foundation top rotation angle deviation should be guaranteed to be ≤2‰; after the foundation sinks, the foundation top horizontality should be measured, and the horizontality deviation should be guaranteed to be ≤3‰;

[0057] Step 4: Device recovery:

[0058] When the barrel foundation is penetrated into place, various parameters of the barrel foundation are re-measured. After the parameters are verified to meet the design requirements, a two-part recovery operation is performed after the device recovery command is issued, namely, the vacuum pump 4.2 is separated from the barrel foundation and the suction claw 4.1 is separated from the barrel foundation.

[0059] Furthermore, the required negative pressure in the bucket foundation is calculated by the following method:

[0060] When the bucket foundation is sunk, it is necessary to consider the resistance of the foundation. Based on the effective stress and bearing capacity theory, the sinking resistance of the bucket foundation at the penetration depth z is:

[0061] R=R side +R tip =A wall ·α·s u +(N c ·s u,tip +γ'·z)A tip (1)

[0062] Among them, Awall is the sum of the contact areas between the inner and outer walls of the bucket and the soil; Atip is the bottom area of ​​the foundation; s uis the average direct shear undrained shear strength at the penetration depth; α is the friction coefficient of the bucket wall, and it is recommended to take 1 / St (St is the soil sensitivity); su,tip is the average undrained shear strength of the bucket end in triaxial compression, triaxial tension, and direct shear; γ' is the effective weight of the soil; Nc is the bearing capacity coefficient under plane strain conditions, which can be taken as 6.2 to 9 according to the penetration depth-to-diameter ratio of the bucket foundation; z is the penetration depth.

[0063] Based on this, the negative pressure required for the bucket foundation to sink is:

[0064] Δu n =(R-W') / A c (2)

[0065] Where: W' is the basic floating weight; A c It is the negative pressure loading plane area in the barrel.

[0066] When the negative pressure is too large, the soil at the end of the bucket flows into the bucket to produce a high soil plug, which affects the foundation penetration. Therefore, the maximum allowable negative pressure for sinking is:

[0067] Δu a =N c ·s u,tip +A in ·α·s u / A c (3)

[0068] Among them, A in It is the contact area between the inner wall of the barrel and the soil.

[0069] The load required for leveling is related to the actual tilt and changes dynamically. The leveling force applied by the telescopic rod 4.3 should be gradually increased from 0.

[0070] The embodiments described above are only descriptions of the preferred modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations, modifications, and substitutions made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A sinking construction system for a barrel foundation, characterized in that: It includes a hydraulic system (3), a leveling system (4) and a vacuum pump suction system (5); The hydraulic system (3) comprises a bracket and a boom, the boom is mounted on the bracket, and the leveling system (4) is arranged at the lifting end of the boom; The leveling system (4) comprises a suction claw (4.1), a vacuum pump (4.2), a telescopic rod (4.3), and an annular fixing frame; the annular fixing frame is sleeved on the barrel-shaped foundation, a plurality of the suction claws (4.1) are mounted on the annular fixing frame, the plurality of the suction claws (4.1) are respectively connected to the telescopic rod (4.3), the top of the telescopic rod (4.3) is rotatably connected to the annular top frame, the annular top frame is fixedly connected to the lifting end of the boom, and the telescopic rod (4.3) is used to drive the suction claw (4.1) to push the barrel-shaped foundation to deflect, thereby realizing the leveling function; The vacuum pump (4.2) is installed on the annular top frame, and the vacuum pump (4.2) is connected to the interior of the barrel foundation through the vacuum pump suction system (5).

2. A barrel foundation sinking construction system according to claim 1, characterized in that: The vacuum pump suction system (5) comprises a vacuum pump interface housing (5.1), an inner ring (5.2), a sealing ring (5.3), an air extraction conduit (5.4), a compression piston (5.5), a traction rope (5.6) and a spring (5.7); The vacuum pump interface shell (5.1) is sleeved on the barrel-shaped foundation, the inner ring (5.2) is slidably arranged on the inner wall surface of the vacuum pump interface shell (5.1), and the inner ring (5.2) is located between the vacuum pump interface shell (5.1) and the barrel-shaped foundation; The sealing ring (5.3) is arranged on the inner side of the end of the inner ring (5.2), and the sealing ring (5.3) is located at one end of the barrel-shaped foundation. The other end of the barrel-shaped foundation is connected to the vacuum pump (4.2) through the exhaust duct (5.4). The exhaust duct (5.4) is connected in parallel with a side tube, and the compression piston (5.5) is arranged in the side tube. The compression piston (5.5) is fixedly connected to the inner ring (5.2) through the traction rope (5.6). A stopper is fixedly arranged on the inner wall surface of the vacuum pump interface shell (5.1), and the spring (5.7) is arranged between the stopper and the inner ring (5.2). The spring (5.7) is sleeved on the traction rope (5.6).

3. A sinking construction method for a barrel foundation, characterized in that: The following steps are involved: The first step is ship anchoring: after the barrel foundation is transported to the construction site, the crane ship arrives at the designated position; Step 2: Foundation hoisting: connect the suction claw (4.1) to the barrel foundation, and connect the vacuum pump (4.2) to the top of the barrel foundation through the air extraction duct (5.4) and the vacuum interface; The third step is foundation penetration: it is divided into two stages, self-sinking into the mud and negative pressure penetration; Self-sinking stage: When the bucket foundation is lowered to 2m from the mud surface, the posture of the bucket foundation is corrected by the suction claw (4.1). After confirmation, continue to lower the bucket foundation until it self-sinks into the mud; When the bucket foundation cannot continue to sink by its own weight, it will enter the negative pressure penetration stage after being left still for 3 hours: the vacuum pump (4.2) will evacuate the air and the monitoring system (1) will monitor the real-time pressure difference between the inside and outside of the bucket foundation and the sinking posture, so that the bucket foundation can be smoothly penetrated under the action of a reasonable pressure difference between the inside and outside; Step 4: Device recovery: After the barrel foundation is penetrated into place, various parameters of the barrel foundation are re-measured. After the parameters are verified to meet the design requirements, the vacuum pump (4.2) and the suction claw (4.1) are separated from the barrel foundation.

4. The sinking construction method of a barrel foundation according to claim 3 is characterized in that: The required negative pressure in the bucket foundation is calculated by the following method: When the bucket foundation is sunk and placed, the sinking resistance at the penetration depth z is: R=R side +R tip =A wall ·a·s u +(N c ·s u,tip +γ'·z)A tip (1) Among them, A wall A is the sum of the contact areas between the inner and outer walls of the barrel and the soil; tip is the base bottom area; s u is the average direct shear undrained shear strength at penetration depth; α is the friction coefficient of the barrel wall; s u,tip is the average undrained shear strength of bucket end triaxial compression, triaxial tension and direct shear; γ' is the effective weight of soil; N c is the bearing capacity coefficient under plane strain conditions; z is the penetration depth; The negative pressure required for the bucket foundation to sink is: Δu n =(R-W') / A c (2) Where: W' is the basic floating weight; A c It is the negative pressure loading plane area in the barrel; The maximum allowable negative pressure for sinking is: Thu a =N c ·s u,tip +A in ·a·s u / A c (3) Among them, A in It is the contact area between the inner wall of the barrel and the soil.

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