High-water-content soft soil in-situ preheating, stirring and reinforcing integrated equipment and construction process thereof

Abstract

The invention discloses high-water-content soft soil in-situ preheating, stirring and reinforcing integrated equipment and a construction technology thereof.The integrated equipment comprises a walking platform, a vertical transmission device fixedly installed on the walking platform, a stirring power box fixedly installed on the vertical transmission device and a stirring shaft installed in the stirring power box; and a curing agent management station; a microwave heating assembly and a curing agent conveying pipeline are arranged in the stirring shaft, and the upper end of the curing agent conveying pipeline extends out of the stirring shaft and is connected with a curing agent management station through a hose. Rapid oscillation of water molecules in the soil body is caused by microwaves, temperature rise of pore water in the soil body is achieved, and therefore the soil body is heated, the adverse effect of cold climate conditions on chemical reaction of the curing agent is overcome, the chemical reaction speed between the curing agent and the soil body is increased, and sufficient cementation of the curing agent and the soil body is promoted; and rapid in-situ reinforcement of the high-water-content soft soil is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical engineering, and in particular to an integrated device for in-situ preheating, stirring and reinforcing of high-water-content soft soil and a construction process thereof. Background Art

[0002] Cement-soil mixing pile technology is a soft soil in-situ reinforcement technology widely used at home and abroad. During construction, a curing agent is sprayed into the soil while the curing agent and the soil are evenly mixed. A series of physical and chemical reactions between the curing agent and the soil are used to bond the soil particles together to form a vertical pile in the soil, which forms a cement-soil mixing pile composite foundation with the surrounding soil to achieve the purpose of reinforcing the soft soil foundation.

[0003] For soft soil layers with high water content, during construction, the curing agent often escapes from the pile body through the numerous pores in the soil layer, resulting in insufficient curing agent content within the pile body, and ultimately causing insufficient strength of the cement soil mixing pile body within the depth range of the high water content soil layer. The use of a curing agent with a fast setting speed can allow the curing agent to quickly bond with the soil and block the curing agent's escape route, but it is very easy to cause the curing agent delivery pump and delivery pipeline to be blocked, resulting in equipment damage and delays in construction. Especially in cold winter climate conditions, the temperature of the upper soil layer drops sharply and even freezes. At this time, the curing agent is affected by the low temperature and cannot smoothly undergo chemical reactions such as hydration, making it difficult to form the pile body. At present, there is no relevant technical method to effectively solve the above problems of cement soil mixing piles. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an integrated in-situ preheating, stirring and consolidation device for high-water content soft soil and a construction process thereof.

[0005] The technical solution adopted by the present invention is:

[0006] An integrated in-situ preheating, stirring and consolidation device for high-water content soft soil, comprising a walking platform, a vertical transmission device fixedly installed on the walking platform, a stirring power box fixedly installed on the vertical transmission device, a stirring shaft installed in the stirring power box, and a curing agent management station;

[0007] A retractable stirring blade is arranged at the lower end of the stirring shaft, a microwave heating component and a curing agent delivery pipeline are arranged in the stirring shaft, a microwave outlet is arranged on the outer wall of the stirring shaft by the microwave heating component, the upper end of the curing agent delivery pipeline extends out of the stirring shaft and is connected to the curing agent management station through a hose, and the lower end of the curing agent delivery pipeline extends to the lower end of the stirring shaft and extends below the retractable stirring blade to form a curing agent outlet;

[0008] The stirring shaft is driven to rotate by the stirring power box and is driven to move up and down by the vertical transmission device to perform drilling and lifting operations.

[0009] Furthermore, the stirring shaft is a hollow cylindrical shaft, the lower end of which is closed to form a conical drill bit.

[0010] Furthermore, the microwave heating assembly comprises a plurality of magnetrons evenly distributed along the axial direction of the stirring shaft, and one end of the magnetron extends out of the outer wall of the stirring shaft to form a microwave outlet.

[0011] Furthermore, the upper end of the curing agent delivery pipeline is connected to the hose through a rotary joint, and one end of the curing agent delivery pipeline extending out of the stirring shaft is welded to the stirring shaft.

[0012] Furthermore, the retractable stirring blades are arranged in a plurality of layers at equal intervals along the axial direction of the stirring shaft, and two are symmetrically arranged in each layer.

[0013] Furthermore, the retractable stirring blade is in a straight line shape and can be rotatably mounted on the stirring shaft through a hinge seat. Several retractable stirring blades on the same side are connected to the cylinder through a connecting rod assembly and are driven by the cylinder to open or close along the axial direction of the stirring shaft.

[0014] Furthermore, the vertical transmission device is installed at the front end of the walking platform, a counterweight block is arranged at the rear end of the walking platform, and telescopic legs are symmetrically arranged on both sides of the walking platform.

[0015] Furthermore, a control room is arranged on the walking platform, and a PLC controller is arranged in the control room. The PLC controller is connected with the walking platform, the vertical transmission device, the power box, the retractable stirring blade and the curing agent management station.

[0016] Furthermore, the curing agent management station is used for the preparation, storage and delivery of the curing agent.

[0017] The construction process of the high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment described in any one of the above items comprises the following steps:

[0018] (1) Level the site and lay a layer of metal plates at the reinforcement point, with the metal plates covering at least the ground within 1 meter around the reinforcement point;

[0019] (2) The walking platform drives the stirring shaft to move to a reinforcement point, the retractable stirring blade is closed, and the stirring shaft is controlled to rotate while drilling down to 0.5 meters below the ground. The microwave heating component is turned on to allow the stirring shaft to preheat the soil while drilling down;

[0020] (3) When the agitator shaft is drilled down to the specified reinforcement depth, lift the agitator shaft upward until it is 0.5 meters below the ground;

[0021] (4) The retractable stirring blade is opened, and the curing agent management station delivers the curing agent to the curing agent delivery pipeline, and the stirring shaft simultaneously drills, stirs, and heats the soil;

[0022] (5) After the stirring shaft is drilled down to the specified reinforcement depth, the stirring shaft is lifted upward, and the microwave heating component is turned off when it is lifted to 0.5 meters below the ground. When it is lifted to the ground, the delivery of the curing agent is stopped, and the foundation reinforcement at this point is completed;

[0023] (6) Move the equipment to the next point and repeat steps (2) to (5) until all reinforcement points in the site are reinforced.

[0024] The beneficial effects of the present invention are as follows: microwaves are used to induce rapid oscillation of water molecules in the soil, thereby heating the pore water in the soil and heating the soil, so as to overcome the adverse effects of cold climate conditions on the chemical reaction of the curing agent, increase the chemical reaction rate between the curing agent and the soil, promote full bonding between the curing agent and the soil, and achieve rapid in-situ reinforcement of high-water content soft soil; the present invention solves the limitation of cold climate on the reinforcement of high-water content soft soil, and provides a rapid reinforcement scheme for high-water content soft soil. The method is applicable to existing soft soil reinforcement materials, and the construction is convenient, fast, economical and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the integrated device of the present invention.

[0026] Figure 2 It is a schematic diagram of the stirring shaft structure of the present invention.

[0027] Figure 3 This is a diagram of the retractable stirring blade in the open state.

[0028] Figure 4 This is a diagram of the closed state of the retractable stirring blade.

[0029] Among them, 1. stirring power box; 2. magnetron outlet; 3. stirring shaft; 4. curing agent outlet; 5. rigid connection; 6. vertical transmission device; 7. hose; 8. control room; 9. walking platform; 10. track wheel; 11. curing agent management station; 12. magnetron; 13. curing agent delivery pipeline; 14. retractable stirring blade; 141. articulated seat; 15. cylinder; 16. connecting rod assembly; 161. first connecting rod; 162. second connecting rod. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and a preferred implementation manner.

[0031] Example 1

[0032] See also Figure 1-Figure 4The present embodiment provides an integrated in-situ preheating, stirring and consolidation device for high-water content soft soil, including a walking platform 9, a vertical transmission device 6, a stirring power box 1, a stirring shaft 3, and a curing agent management station 11; the vertical transmission device 6 is fixedly installed at the front end of the walking platform 9, the stirring power box 1 is fixedly installed on the moving component of the vertical transmission device 6, the stirring shaft 3 is rotatably installed in the stirring power box 1, and a retractable stirring blade 14 is provided at the lower end of the stirring shaft 3. A microwave heating component and a curing agent delivery pipeline 13 are provided in the stirring shaft 3. The microwave heating component is provided with a microwave outlet on the outer wall of the stirring shaft. The upper end of the curing agent delivery pipeline 13 extends out of the stirring shaft 3 and is connected to the curing agent management station 11 through a hose 7. The lower end of the curing agent delivery pipeline 13 extends to the lower end of the stirring shaft 3 and extends below the retractable stirring blade 14 to form a curing agent outlet 4; the stirring shaft 3 is driven to rotate by the stirring power box 1, and is driven to move up and down by the vertical transmission device 6 to perform drilling and lifting operations.

[0033] The walking platform 9 is a prior art, and is used to bear the weight of equipment such as the stirring shaft, stirring power box, and vertical transmission device. The walking platform 9 can flexibly select a variety of moving modes such as crawlers and rollers according to site conditions. In this embodiment, the walking platform 9 is crawler-type, and the platform body is rectangular, about 5 meters long and about 3 meters wide. A counterweight is set at its rear end, and telescopic legs are symmetrically arranged on both sides to prevent overturning.

[0034] The vertical transmission device 6 is a prior art, and is used to control the stirring shaft 3 to move in the vertical direction to complete the drilling and lifting operations. For example, the vertical transmission device 6 can be driven by a servo motor to drive a ball screw nut, and the stirring power box 1 is fixedly connected to the nut.

[0035] The stirring power box 1 is a prior art, and its connection method with the stirring shaft 3 and its working principle are not described in detail here.

[0036] In this embodiment, the stirring shaft 3 is a hollow cylindrical shaft, the length of which is slightly greater than the reinforcement depth, and the lower end thereof is closed to form a conical drill bit.

[0037] A plurality of magnetrons 12 are arranged at equal intervals of about 50 cm in the axial direction of the stirring shaft 3. The stirring shaft 3 is opened at the position corresponding to the magnetron. The open end of the magnetron 12 extends out of the stirring shaft opening to form a microwave outlet. The extended end of the magnetron 12 is welded to the stirring shaft to prevent the soil from drilling into the stirring shaft from the opening and to stabilize the magnetron. The plurality of magnetrons 12 form a microwave heating assembly to preheat the high-water content soft soil in situ by microwave.

[0038] A circular hole is opened 20 cm above the conical drill bit of the stirring shaft 3 as a grouting port, and the lower end of the curing agent delivery pipeline 13 passes through the grouting port to form a curing agent outlet 4. The curing agent delivery pipeline is fully welded to the grouting port to prevent the soil from drilling into the stirring shaft from the opening and to stabilize the position of the grouting port.

[0039] The upper end of the curing agent delivery pipeline 13 extends out of the stirring shaft 3 and is connected to the hose 7 through a rotary joint, and the other end of the hose 7 is connected to the delivery pump of the curing agent management station 11. The curing agent management station 11 is a prior art and is used for the preparation, storage and delivery of curing agents.

[0040] The retractable stirring blades 14 are arranged in 4 to 8 layers at equal intervals of 30 to 50 cm along the axial direction of the stirring shaft, and two are symmetrically arranged in each layer. The retractable stirring blades 14 can be straight blades in a straight line or curved blades in an arc shape, and can be opened or closed along the axial direction of the stirring shaft or opened or closed along the radial direction of the stirring shaft.

[0041] In this embodiment, the retractable stirring blade 14 is in a straight line shape, and 4 layers are arranged at intervals of 30 cm. Each retractable stirring blade 14 is rotatably mounted on the stirring shaft through an articulated seat 141. Specifically, the articulated seat 141 includes a seat body and an articulated shaft. The root of the retractable stirring blade 14 is fixedly sleeved on the intersection shaft, and the articulated shaft is rotatably connected to the seat body. The four retractable stirring blades 14 on the same side are connected to the cylinder 15 through a connecting rod assembly 16. The connecting rod assembly 16 includes a first connecting rod 161 and a second connecting rod 162. The number of the second connecting rod 162 is consistent with that of the retractable stirring blade 14. One end of the second connecting rod 162 is fixedly connected to the articulated shaft of the retractable stirring blade 14. The other end of the second connecting rod 162 is provided with a waist-shaped hole. Each second connecting rod 162 is hinged to the first connecting rod 161 through a rotating shaft A passing through the waist-shaped hole. The first connecting rod 161 is arranged along the axial direction of the stirring shaft, and its upper end is fixedly connected to the cylinder piston rod.

[0042] The piston rod of the cylinder 15 extends, pushing the first connecting rod 161 downward, the right hinge shaft rotates clockwise, and the left hinge shaft rotates counterclockwise, and the retractable stirring blades 14 on both sides are transformed from an open state to a closed state that fits the shaft body of the stirring shaft; the cylinder piston rod retracts, and the retractable stirring blades 14 are transformed from a closed state to an open state.

[0043] For the convenience of operation, in the present embodiment, a control room 8 is also provided on the walking platform 9, and a PLC controller is provided in the control room 8. The PLC controller is connected to the walking motor of the walking platform 9, the transmission motor of the vertical transmission device 6, the rotating motor of the power box 1, the cylinder of the retractable stirring blade 14, and the delivery pump, stirring motor and other electrical equipment of the curing agent management station 11, so as to automatically control the preheating time, stirring speed, stirring direction, stirring blade retraction, drilling down, lifting the drill and other actions of the stirring shaft.

[0044] Example 2

[0045] This embodiment provides a construction process of the high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment as described in Embodiment 1, comprising the following steps:

[0046] (1) The site is leveled and a layer of metal plates is laid at the reinforcement point. The metal plates cover at least the ground within 1 meter around the reinforcement point. The operator controls the equipment in the control room 8, and the equipment moves to the reinforcement point via the track wheels 10;

[0047] (2) closing the retractable stirring blade 14, controlling the stirring shaft 3 to rotate and drill down to 0.5 m below the ground, and then turning on the magnetron 12 to allow the stirring shaft to preheat the soil while drilling down;

[0048] (3) When the agitator shaft 3 is drilled down to the specified reinforcement depth, the agitator shaft 3 is lifted upward until it is 0.5 meters below the ground;

[0049] (4) The retractable stirring blade 14 is opened, and the curing agent management station 11 delivers the curing agent to the curing agent delivery pipeline 13, and the stirring shaft simultaneously performs drilling, stirring, and heating of the soil; during this period, the stirring shaft 3 is controlled to perform drilling, stirring, and heating of the soil simultaneously;

[0050] (5) After the stirring shaft 3 is drilled down to the designated reinforcement depth, the stirring shaft 3 is lifted upward, and the magnetron 12 is turned off when it is lifted to 0.5 meters below the ground. When it is lifted to the ground, the delivery of the curing agent is stopped, and the foundation reinforcement at this point is completed;

[0051] (6) The equipment is moved to the next point and steps (2) to (5) are repeated until all reinforcement points in the site are reinforced.

[0052] Application Example 3

[0053] In order to verify the effect of the present invention on improving the strength of the cement-soil mixing pile body, a cement-soil mixing pile construction test was carried out using an SCJB-C model single-axis mixing pile machine and the integrated equipment described in Example 1 of the present invention. The test site was selected from a highway construction project in Lianyungang, Jiangsu Province. The soft soil layer was 10 meters thick and the moisture content was as high as 120%.

[0054] The present invention is constructed according to the construction method described in Example 2.

[0055] 14 days and 28 days after the construction was completed, the quality of the test piles was tested by standard penetration test, coring test and unconfined compressive strength test. The test results are shown in Table 1.

[0056] The test method refers to the "Highway Engineering Cement Mixing Piles Quality Inspection Procedure" (DB32 / T 2283-2012).

[0057] Table 1

[0058]

[0059] It can be seen from Table 1 that the cement-soil mixing piles constructed using the present invention are significantly better in uniformity and pile body strength than conventional mixing piles.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also within the protection scope of the present invention.

Claims

1. An integrated equipment for in-situ preheating, stirring and consolidation of high-water content soft soil, characterized in that: It comprises a walking platform (9), a vertical transmission device (6) fixedly mounted on the walking platform (9), a stirring power box (1) fixedly mounted on the vertical transmission device (6), a stirring shaft (3) mounted in the stirring power box (1), and a curing agent management station (11); A retractable stirring blade (14) is provided at the lower end of the stirring shaft (3); a microwave heating component and a curing agent delivery pipeline (13) are provided inside the stirring shaft (3); the microwave heating component is provided with a microwave outlet on the outer wall of the stirring shaft; the upper end of the curing agent delivery pipeline (13) extends out of the stirring shaft (3) and is connected to the curing agent management station (11) through a hose (7); the lower end of the curing agent delivery pipeline (13) extends to the lower end of the stirring shaft (3) and extends below the retractable stirring blade (14) to form a curing agent outlet (4); The stirring shaft (3) is driven to rotate by the stirring power box (1) and is simultaneously driven to move up and down by the vertical transmission device (6) to perform drilling and lifting operations.

2. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: The stirring shaft (3) is a hollow cylindrical shaft, the lower end of which is closed to form a conical drill bit.

3. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: The microwave heating assembly comprises a plurality of magnetrons (12) uniformly distributed along the axial direction of the stirring shaft, and one end of the magnetron (12) extends out of the outer wall of the stirring shaft to form a microwave outlet.

4. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: The upper end of the curing agent delivery pipeline (13) is connected to the hose (7) via a rotary joint, and one end of the curing agent delivery pipeline (13) extending out of the stirring shaft is welded to the stirring shaft (3).

5. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: The retractable stirring blades (14) are arranged in a plurality of layers at equal intervals along the axial direction of the stirring shaft, and two blades are symmetrically arranged in each layer.

6. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 5 is characterized in that: The retractable stirring blade (14) is in a straight line shape and is rotatably mounted on the stirring shaft via a hinge seat (141). A plurality of retractable stirring blades (14) on the same side are connected to the cylinder (15) via a connecting rod assembly (16) and are driven by the cylinder (15) to open or close along the axial direction of the stirring shaft.

7. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: The vertical transmission device (6) is installed at the front end of the walking platform (9), a counterweight block is arranged at the rear end of the walking platform (9), and telescopic legs are symmetrically arranged on both sides of the walking platform (9).

8. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1 is characterized in that: A control room (8) is provided on the walking platform (9), and a PLC controller is provided in the control room (8). The PLC controller is connected to the walking platform (9), the vertical transmission device (6), the power box (1), the retractable stirring blade (14) and the curing agent management station (11).

9. The high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to claim 1, characterized in that: The curing agent management station (11) is used for the preparation, storage and transportation of the curing agent.

10. The construction process of the high-water content soft soil in-situ preheating, stirring and consolidation integrated equipment according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Level the site and lay a layer of metal plates at the reinforcement point, with the metal plates covering at least the ground within 1 meter around the reinforcement point; (2) The walking platform (9) drives the stirring shaft (3) to move to a reinforcement point, the retractable stirring blade (14) is closed, and the stirring shaft is controlled to rotate while drilling down to 0.5 meters below the ground, and the microwave heating component is turned on to allow the stirring shaft to preheat the soil while drilling down; (3) When the agitator shaft (3) is drilled down to the specified reinforcement depth, the agitator shaft (3) is lifted upward to a position 0.5 m below the ground; (4) The retractable stirring blade (14) is opened, and the curing agent management station (11) delivers the curing agent to the curing agent delivery pipeline (13), and the stirring shaft simultaneously performs drilling, stirring, and heating of the soil; (5) After the stirring shaft (3) is drilled down to the designated reinforcement depth, the stirring shaft (3) is lifted upward, and when it is lifted to 0.5 meters below the ground, the microwave heating component is turned off, and when it is lifted to the ground, the delivery of the curing agent is stopped, thereby completing the foundation reinforcement at the point; (6) The equipment is moved to the next point and steps (2) to (5) are repeated until all reinforcement points in the site are reinforced.

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