Multi-node adaptive combined pile based on monitoring data and its application method

Abstract

The present invention relates to a multi-node adaptive composite pile based on monitoring data, comprising a steel pipe for construction structure, a spiral blade with a steel ring tube, a strain measurement unit, and a monitoring and control system. The stable and unchanging welded connection between the spiral blade and the steel pipe in the spiral steel pipe-cement soil composite pile is transformed into a friction connection. The oil pressure in the steel ring tube wall is controlled and regulated by monitoring data to control the friction resistance between the contact surface of the steel ring tube and the steel pipe. During the load-bearing process, the pile body adaptively transfers more load to the lower spiral blade, and at the same time, the stress is redistributed to achieve the purpose of uniform load distribution. This greatly alleviates the problem of stress concentration at the connection between the original upper spiral blade and the steel pipe, better conforms to the load transfer theory of rigid cement soil composite piles, and the pile body can better provide compressive bearing capacity while also better providing tensile bearing capacity, thereby improving the stress state of the structure, increasing reliability, and exerting better load-bearing performance.

Description

Technical Field

[0001] The present invention relates to the technical field of pile foundations, and in particular to a multi-node adaptive combined pile based on monitoring data and an application method thereof. Background Art

[0002] In the infrastructure construction of various projects, pile foundations can often provide considerable bearing capacity, but this is accompanied by high construction costs and huge consumption of energy and materials. In some engineering construction projects that only require a smaller bearing capacity, such as the construction of photovoltaic power stations on coastal mudflats, a large amount of resources are often wasted in order to meet the minimum requirements of the specifications. In this case, if you choose to use reinforced cement-soil composite piles, it will greatly reduce the cost and energy consumption.

[0003] Reinforced cement-soil composite piles are a new type of combined pile in which, after the construction of the cement-soil mixing piles is completed, the rigid core pile is vertically implanted into the cement-soil mixing piles so that the outer periphery is wrapped with cement soil. They have both the larger pile side friction resistance of the cement-soil mixing piles and the higher strength and stiffness of the core piles.

[0004] At present, the rigid core piles in rigid cement-soil composite piles are in the form of pipe piles, steel pipes, spiral steel pipes, etc. Among them, for the rigid cement-soil composite piles with spiral steel pipes as the inner core, the load they bear is mostly concentrated on the upper spiral blades. There is stress concentration at the welding position between the steel pipe and the spiral blades, while the lower spiral blades share too little load. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a multi-node adaptive composite pile based on monitoring data and its application method. Through the different frictional resistances between each spiral blade and the steel pipe, the load is adaptively transferred more, greatly alleviating the stress concentration problem at the connection between the upper spiral blade and the steel pipe, and better complying with the load transfer theory of rigid cement-soil composite piles.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A multi-node adaptive composite pile based on monitoring data, including a steel pipe for the construction structure, a spiral blade with a steel ring, a strain measurement unit, and a monitoring and control system;

[0008] Holes for the hydraulic oil circuit to pass through are reserved on the wall of the steel pipe;

[0009] The spiral blade with the steel ring is made in an integrated manner, and a hydraulic bag space is reserved inside the wall of the steel ring. The hydraulic oil circuit connected to the hydraulic bag extends out of the steel pipe after passing through the hole.

[0010] The strain measuring unit is attached to the inner surface of the steel pipe and arranged in a circumferential direction to monitor the deformation of the steel pipe;

[0011] The monitoring and control system includes a field monitoring device and a computer. The input end of the field monitoring device is electrically connected to the strain measurement unit, and the output end is electrically connected to the hydraulic oil pump to collect, process, and store deformation data of the steel pipe and transmit it to the computer, and receive commands from the computer to regulate the hydraulic oil pressure in the hydraulic bag space;

[0012] The spiral blade with the steel ring tube is assembled at the specified position of the steel pipe, and the hydraulic oil in the hydraulic bag space is pressurized to squeeze the wall of the steel ring tube, and then the steel ring tube squeezes the steel pipe, so that the two are in close contact; during the load-bearing process, when the load value continues to increase, the monitoring and control system detects that the load of the first spiral blade is too large, and it sends a command to the hydraulic oil pump to reduce the oil pressure in the steel ring tube wall of the first spiral blade, reduce the tightness between the steel ring tube and the steel pipe, and then reduce the frictional resistance between the two. At this time, the steel pipe has a tendency to slide downward, but the lower spiral blade starting from the second spiral blade prevents the steel pipe from sliding downward. At this time, the load of the second spiral blade increases rapidly. When it is detected that the load of the second spiral blade is too large, the monitoring and control system sends a command to the hydraulic oil pump to reduce the oil pressure in the steel ring tube wall of the second spiral blade. The subsequent steps are carried out in this way, and the load is gradually transferred and the stress is redistributed to achieve the purpose of uniform load distribution and better load-bearing performance.

[0013] Furthermore, the steel pipe can be replaced by a carrier made of glass fiber reinforced plastic.

[0014] Furthermore, the outer surface of the steel pipe and the inner surface of the steel ring are roughened to reduce the working pressure of the hydraulic oil pump, the steel ring and the steel pipe.

[0015] Furthermore, by extending the length of the steel ring tube, the frictional resistance is increased and the load capacity of the single-pass spiral blade is improved.

[0016] Furthermore, there are multiple strain measuring units, each of which is attached to a different position of the steel pipe to monitor the deformation of the steel pipe at different positions.

[0017] The application method of the multi-node adaptive combined pile based on monitoring data of the present invention comprises the following steps:

[0018] (1) Detect underground obstacles in the application area, remove obstacles and backfill soil in a timely manner, level the site, and compact it layer by layer;

[0019] (2) Excavate to the designed elevation, measure and position the earthwork according to the requirements, and make permanent and temporary markings;

[0020] (3) Position the three-axis mixing pile hole, put the pile driver in place, prepare and inject cement slurry as required, and control the sinking and lifting speed of the mixing pile as required;

[0021] (4) Multi-node adaptive composite piles based on monitoring data are implanted to ensure the pile position, verticality and elevation of the pile body. Monitoring and control will be carried out after the foundation construction is completed.

[0022] By adopting the above technical solution, the present invention has the following beneficial effects:

[0023] By transforming the stable and unchanging welding connection between the spiral blades and the steel pipe in the spiral steel pipe-cement soil composite pile into a friction connection, and controlling the oil pressure in the steel ring tube wall through monitoring data to control and adjust the friction resistance between the contact surface of the steel ring tube and the steel pipe, the pile body is adaptively and continuously transferring more load to the lower spiral blades during the load-bearing process, and at the same time redistributing the stress to achieve the purpose of uniform load distribution. This greatly alleviates the problem of stress concentration at the connection between the original upper spiral blades and the steel pipe, and better conforms to the load transfer theory of rigid cement soil composite piles. The pile body can better provide compressive bearing capacity while also better providing tensile bearing capacity, which improves the stress state of the structure, increases reliability, and exerts better bearing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0025] Figure 1 This is the overall schematic diagram of the multi-node adaptive composite pile based on monitoring data;

[0026] Figure 2 A schematic diagram of a steel pipe with holes reserved for the hydraulic oil circuit;

[0027] Figure 3 Schematic diagram of a spiral blade with a steel ring;

[0028] Figure 4 This is a schematic diagram of the longitudinal section of a multi-node adaptive composite pile based on monitoring data;

[0029] In the figure: 1-steel pipe; 2-spiral blade; 3-steel ring cylinder; 4-hole; 5-hydraulic bladder space; 6-hydraulic oil circuit; 7-strain measurement unit; 8-wire. DETAILED DESCRIPTION

[0030] like Figure 1-4 As shown, the multi-node adaptive composite pile based on monitoring data of the present invention includes a steel pipe 1 for construction structure, a spiral blade 2 with a steel ring cylinder 3, a strain measurement unit 7 and a monitoring control system;

[0031] The steel pipe 1 used for the construction structure is a commonly used steel pipe 1 for construction. A hole 4 for the hydraulic oil circuit 6 to pass through is reserved on the wall of the steel pipe 1. The steel pipe 1 can also be replaced by a carrier made of glass fiber reinforced plastic or other materials.

[0032] The spiral blade 2 with the steel ring 3 has dimensions calculated according to the original project, but the original "welded" connection between the spiral blade 2 and the steel pipe 1 has been eliminated. Instead, the spiral blade 2 is manufactured in an integrated manner, with a space 5 for a hydraulic bladder reserved within the wall of the steel ring 3. The hydraulic oil line 6 connected to the hydraulic bladder extends through a hole 4 and out of the steel pipe 1.

[0033] The strain measuring unit 7 is attached to the inner surface of the steel pipe 1 and arranged along the circumferential direction to monitor the deformation of the steel pipe 1. Preferably, there are multiple strain measuring units 7, each of which is attached to a different position of the steel pipe 1 to monitor the deformation of the steel pipe 1.

[0034] The monitoring and control system includes a field monitoring device and a computer. The input end of the field monitoring device is electrically connected to the strain measurement unit 7 through a wire 8, and the output end is electrically connected to the hydraulic oil pump to collect, process, and store the deformation data of the steel pipe 1, and transmit it to the computer, and receive commands from the computer to regulate the hydraulic oil pressure in the hydraulic bag space 5.

[0035] During use, the spiral blade 2 with the steel ring cylinder 3 is assembled at the specified position of the steel pipe 1, and the hydraulic oil in the hydraulic bag space 5 is pressurized to squeeze the wall of the steel ring cylinder 3, and then the steel ring cylinder 3 squeezes the steel pipe 1, so that the two are in close contact with greater friction resistance; during the load-bearing process, when the load value continues to increase, the monitoring and control system detects that the load of the first spiral blade 2 is too large, and it sends a command to the hydraulic oil pump to reduce the oil pressure in the wall of the steel ring cylinder 3 of the first spiral blade 2, reduce the tightness between the steel ring cylinder 3 and the steel pipe 1, and then reduce the friction resistance between the two. At this time, the steel pipe 1 has a tendency to slide downward, but the lower spiral blade 2 starting from the second spiral blade 2 prevents the steel pipe 1 from sliding downward. At this time, the load of the second spiral blade 2 increases rapidly. When it is detected that the load of the second spiral blade 2 is too large, the monitoring and control system sends a command to the hydraulic oil pump to reduce the oil pressure in the wall of the steel ring cylinder 3 of the second spiral blade 2. The subsequent steps are carried out in this way, and load transfer and stress redistribution are gradually carried out to achieve the purpose of uniform load distribution and better load-bearing performance. After the above arrangement, the pile body can better provide compressive bearing capacity as well as tensile bearing capacity.

[0036] The outer surface of the steel pipe 1 and the inner surface of the steel ring cylinder 3 can be roughened to reduce the working pressure of the hydraulic oil pump, the steel ring cylinder 3 and the steel pipe 1. In addition, the friction resistance can be increased by extending the length of the steel ring cylinder 3, thereby improving the load capacity of the single-pass spiral blade 2.

[0037] The application method of the multi-node adaptive combined pile based on monitoring data of the present invention comprises the following steps:

[0038] (1) Detect underground obstacles in the application area, remove obstacles and backfill soil in a timely manner, level the site, and compact it layer by layer;

[0039] (2) Excavate to the designed elevation, measure and position the earthwork according to the requirements, and make permanent and temporary markings;

[0040] (3) Position the three-axis mixing pile hole, put the pile driver in place, prepare and inject cement slurry as required, and control the sinking and lifting speed of the mixing pile as required;

[0041] (4) Multi-node adaptive composite piles based on monitoring data are implanted to ensure the pile position, verticality and elevation of the pile body. Monitoring and control will be carried out after the foundation construction is completed.

[0042] The above describes a specific embodiment of the present invention, but those skilled in the art should understand that this is only an example. Those skilled in the art can make various changes or modifications to this embodiment without departing from the principles and essence of the present invention, but these changes and modifications will fall within the scope of protection of the present invention.

Claims

1. Multi-node adaptive combined pile based on monitoring data, characterized by: It includes steel pipes for construction structure, spiral blades with steel ring cylinders, strain measurement units and monitoring and control systems; Holes for the hydraulic oil circuit to pass through are reserved on the wall of the steel pipe; The spiral blade with the steel ring is made in an integrated manner, and a hydraulic bag space is reserved inside the wall of the steel ring. The hydraulic oil circuit connected to the hydraulic bag extends out of the steel pipe after passing through the hole. The strain measuring unit is attached to the inner surface of the steel pipe and arranged along the circumferential direction to monitor the deformation of the steel pipe; The monitoring and control system includes a field monitoring device and a computer. The input end of the field monitoring device is electrically connected to the strain measurement unit, and the output end is electrically connected to the hydraulic oil pump to collect, process, and store deformation data of the steel pipe and transmit it to the computer, and receive commands from the computer to regulate the hydraulic oil pressure in the hydraulic bag space; The spiral blade with the steel ring tube is assembled at the specified position of the steel pipe, and the hydraulic oil in the hydraulic bag space is pressurized to squeeze the wall of the steel ring tube, and then the steel ring tube squeezes the steel pipe, so that the two are in close contact; during the load-bearing process, when the load value continues to increase, the monitoring and control system detects that the load of the first spiral blade is too large, and it sends a command to the hydraulic oil pump to reduce the oil pressure in the steel ring tube wall of the first spiral blade, reduce the tightness between the steel ring tube and the steel pipe, and then reduce the frictional resistance between the two. At this time, the steel pipe has a tendency to slide downward, but the lower spiral blade starting from the second spiral blade prevents the steel pipe from sliding downward. At this time, the load of the second spiral blade increases rapidly. When it is detected that the load of the second spiral blade is too large, the monitoring and control system sends a command to the hydraulic oil pump to reduce the oil pressure in the steel ring tube wall of the second spiral blade. The subsequent steps are carried out in this way, and the load is gradually transferred and the stress is redistributed to achieve the purpose of uniform load distribution and better load-bearing performance.

2. The multi-node adaptive combined pile based on monitoring data according to claim 1, characterized in that: The steel pipe is replaced by a carrier made of glass fiber reinforced plastic.

3. The multi-node adaptive combined pile based on monitoring data according to claim 1, characterized in that: The outer surface of the steel pipe and the inner surface of the steel ring cylinder are roughened to reduce the working pressure of the hydraulic oil pump, the steel ring cylinder and the steel pipe.

4. The multi-node adaptive combined pile based on monitoring data according to claim 1, characterized in that: By extending the length of the steel ring, the friction resistance is increased and the load capacity of the single-pass spiral blade is improved.

5. The multi-node adaptive combined pile based on monitoring data according to claim 1, characterized in that: There are multiple strain measuring units, each of which is attached to a different position of the steel pipe to monitor the deformation of the steel pipe at different positions.

6. The application method of the multi-node adaptive composite pile based on monitoring data according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Detect underground obstacles in the application area, remove obstacles and backfill soil in a timely manner, level the site, and compact it layer by layer; (2) Excavate to the designed elevation, measure and position the earthwork according to the requirements, and make permanent and temporary markings; (3) Position the three-axis mixing pile hole, put the pile driver in place, prepare and inject cement slurry as required, and control the sinking and lifting speed of the mixing pile as required; (4) Multi-node adaptive composite piles based on monitoring data are implanted to ensure the pile position, verticality and elevation of the pile body. Monitoring and control will be carried out after the foundation construction is completed.

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