CN205172598U - Pipe curtain spouts a supporting construction soon - Google Patents

Abstract

The utility model discloses a pipe curtain spouts a supporting construction soon, including a plurality of pipes act steel pipe, all be provided with at least one level between per two pipe curtain steel pipes and spout the stake soon, just the marginal in close contact with of stake is spouted soon to pipe curtain steel pipe and level, manages act steel pipe and spouts the stake atress system of strutting jointly of the big rigidity of combination formation together soon with the level. The utility model discloses a to manage an act steel pipe and strut form and level and spout the stake soon and strut the form and make up, and form big rigidity water proofness pipe curtain spouts a supporting construction soon, construction and operation safety are guaranteed in loss that can effective control groundwater, are particularly suitable for burying the supporting construction when wearing sensitive construction under the big section underground structure as saturation rich water weak soil stratum shallow.

Description

Pipe Curtain Rotary Grouting Pile Supporting Structure

technical field

The utility model relates to a civil construction technology, in particular to a pipe-curtain rotary spray pile support structure.

Background technique

With the acceleration of urbanization in China, more and more large underground structures are built under urban roads or important buildings. For shallow-buried urban tunnels with large cross-sections and short distances, it is not economical to use the shield method for construction, and the open-cut method will greatly interfere with urban production and life. When the geological conditions are poor, the burial depth is shallow, and there are sensitive buildings on the upper part, if the shallow buried excavation method is used for construction, the ground subsidence is difficult to control, and once a construction accident occurs, it will cause significant social impact. Therefore, it is very important to find a construction method suitable for shallow-buried large-section underground structures passing through sensitive buildings in saturated water-rich soft soil strata.

Contents of the invention

The purpose of this utility model is to overcome the deficiencies of the above-mentioned prior art, and provide a pipe-curtain swirling pile support structure, which combines the pipe-curtain steel pipe protection form and the horizontal swirling pile support form to form a large rigidity watertight pipe The curtain rotary grouting pile support structure can effectively control the loss of groundwater and ensure the safety of construction and operation. It is especially suitable as a support structure for shallow-buried large-section underground structures in saturated water-rich soft soil strata to pass through sensitive buildings during construction.

In order to achieve the above object, the utility model adopts the following technical solutions:

A pipe-curtain jet-grouting pile support structure, including several pipe-curtain steel pipes, at least one horizontal jet-grouting pile is arranged between every two pipe-curtain steel pipes, and the edges of the pipe-curtain steel pipes and the horizontal jet-grouting piles are in close contact. Curtain steel pipes and horizontal jet grouting piles are combined to form a high-rigidity joint support system.

Two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

More than two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

A pipe curtain jet grouting pile support structure, including several pipe curtain steel pipes, at least one horizontal jet grouting pile is arranged between every two pipe curtain steel pipes, and the edges of the pipe curtain steel pipes and the horizontal jet grouting piles are in close contact, partly The pipe-curtain steel pipe is filled with concrete, and the pipe-curtain steel pipe and the horizontal jet grouting pile are combined to form a high-rigidity common support force system.

Two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

More than two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

The pipe curtain steel pipes filled with concrete and the pipe curtain steel pipes not filled with concrete are arranged at intervals, which can effectively increase the strength of the entire pipe curtain rotary grouting pile support structure.

A pipe-curtain jet-grouting pile support structure includes several pipe-curtain steel pipes, at least one horizontal jet-grouting pile is arranged between every two pipe-curtain steel pipes, and the edges of the pipe-curtain steel pipes and the horizontal jet-grouting piles are in close contact. The above-mentioned pipe-curtain steel pipes are filled with concrete, and the pipe-curtain steel pipes are combined with the horizontal jet grouting piles to form a common support force system with high rigidity.

Two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

More than two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles are in close contact, which can effectively stop water.

The diameter of the pipe screen steel pipe is 0.3m-2m, and a larger diameter can also be selected according to specific engineering conditions. Steel pipes of different diameters are selected according to different actual needs.

The shape of the pipe-curtain rotary grouting pile support structure is arranged in a circular, rectangular or other arbitrary shape, and the specific shape depends on the underground structure to be built.

The utility model combines the support form of pipe-curtain steel pipe and the support form of horizontal jet-spray pile to form a large-rigidity water-tight pipe-curtain jet-spray pile support structure, which can effectively control the loss of groundwater and ensure the safety of construction and operation, especially It is suitable as a support structure for shallow buried large-section underground structures passing through sensitive buildings in saturated water-rich soft soil strata.

Compared with the existing pipe curtain method, the number of pipe curtain steel pipes of the utility model can be greatly reduced, and the reduced pipe curtain steel pipe support function is replaced by horizontal jet grouting piles, which can save construction period and cost; Compared with other forms of protection, the rigidity of the support structure is greatly improved, the deformation of the ground surface can be effectively controlled, and the safety is good. The utility model is particularly suitable as a support structure for a shallow-buried large-section underground structure under a saturated water-rich soft soil stratum to pass through a sensitive building during construction.

Description of drawings

Fig. 1 is the structural representation of the utility model embodiment 1;

Fig. 2 is the structural representation of the utility model embodiment 2;

Fig. 3 is the structural representation of the utility model embodiment 3;

Fig. 4 is a schematic structural view of Embodiment 4 of the utility model;

Fig. 5 is a schematic structural view of Embodiment 5 of the present utility model;

Fig. 6 is a schematic structural view of embodiment 6 of the present invention;

Fig. 7 is the construction process flow diagram of using pipe-curtain rotary grouting pile support structure to build underground works;

Fig. 8 is a construction flow chart of pipe curtain steel pipe jacking;

Fig. 9 is a construction flow chart of the horizontal jet grouting pile;

Among them 1. Pipe curtain steel pipe, 2. Horizontal jet grouting pile, 3. Excavation door, 4. Pipe curtain steel pipe filled with concrete.

detailed description

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Example 1

As shown in Figure 1, the pipe-curtain jet-grouting pile support structure includes several pipe-curtain steel pipes 1, and a horizontal jet-grouting pile 2 is arranged between every two pipe-curtain steel pipes 1, and the pipe-curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, and the pipe-curtain steel pipe 1 and the horizontal jet-grouting pile 2 are combined to form a high-rigidity common support force system. The pipe curtain steel pipe 1 has a diameter of 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a circle.

Example 2:

As shown in Figure 2, the pipe-curtain jet-grouting pile support structure includes several pipe-curtain steel pipes 1, a horizontal jet-grouting pile 2 is arranged between every two pipe-curtain steel pipes 1, and the pipe-curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, and the pipe-curtain steel pipe 1 and the horizontal jet-grouting pile 2 are combined to form a high-rigidity common support force system. The pipe curtain steel pipe 1 has a diameter of 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a rectangle.

Example 3:

As shown in Figure 3, the pipe curtain jet grouting pile support structure includes several pipe curtain steel pipes 1, a horizontal jet grouting pile 2 is arranged between every two pipe curtain steel pipes 1, and the pipe curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, some of the pipe curtain steel pipes are filled with concrete, and the pipe curtain steel pipes 4 filled with concrete and the pipe curtain steel pipes not filled with concrete are arranged at intervals. The pipe curtain steel pipe 1 and the horizontal jet grouting pile 2 are combined together to form a large rigidity common support stress system. The pipe curtain steel pipe 1 has a diameter of 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a circle.

Example 4:

As shown in Figure 4, the pipe-curtain jet-grouting pile support structure includes several pipe-curtain steel pipes 1, and a horizontal jet-grouting pile 2 is arranged between every two pipe-curtain steel pipes 1, and the pipe-curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, some of the pipe curtain steel pipes are filled with concrete, and the pipe curtain steel pipes 4 filled with concrete and the pipe curtain steel pipes not filled with concrete are arranged at intervals. The pipe curtain steel pipe 1 and the horizontal jet grouting pile 2 are combined together to form a large rigidity common support stress system. The pipe curtain steel pipe 1 has a diameter of 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a rectangle.

Example 5:

As shown in Figure 5, the pipe curtain jet grouting pile support structure includes several pipe curtain steel pipes 1, and a horizontal jet grouting pile 2 is arranged between every two pipe curtain steel pipes 1, and the pipe curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, and the pipe-curtain steel pipes are all filled with concrete, and the pipe-curtain steel pipes 4 filled with concrete are combined with the horizontal jet grouting piles to form a high-rigidity common support force system. The diameter of the pipe curtain steel pipe is 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a circle.

Embodiment 6:

As shown in Figure 6, the pipe curtain jet grouting pile support structure includes several pipe curtain steel pipes 1, and a horizontal jet grouting pile 2 is arranged between every two pipe curtain steel pipes 1, and the pipe curtain steel pipes 1 and the horizontal jet grouting The edges of the piles 2 are in close contact, and the pipe-curtain steel pipes are all filled with concrete, and the pipe-curtain steel pipes 4 filled with concrete are combined with the horizontal jet grouting piles to form a high-rigidity common support force system. The diameter of the pipe curtain steel pipe is 0.3m-2m. The shape of the pipe-curtain rotary grouting pile support structure is arranged in a rectangle.

Embodiment 7: Different from Embodiments 1-6, two adjacent horizontal jet grouting piles 2 are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles 2 are in close contact. This embodiment contains 6 new different structures relative to the structural changes of Embodiments 1-6.

Embodiment 8: Different from Embodiments 1-6, more than two adjacent horizontal jet grouting piles 2 are arranged between every two pipe curtain steel pipes, and the edges of every two adjacent horizontal jet grouting piles 2 Close contact. This embodiment contains 6 new different structures relative to the structural changes of Embodiments 1-6.

Below with regard to the technical principle of the utility model and construction scheme, flow process, do further detailed description.

The pipe curtain method is to first use the micro-pipe jacking technology to jack steel pipes or other materials around the proposed underground building. Under the protection of high-rigidity pipe curtains, a method of excavating the soil surrounded by pipe curtains and pouring the main structure.

The pipe curtain method has the following characteristics:

1. The construction of underground structures with large-section pipe-curtain method in soft soil stratum is generally carried out when there is no condition to adopt the open-cut method;

2. Usually, the pipe curtain method is used to construct the underground structure with relatively shallow covering soil, which needs to pass through sensitive pipelines, roads and structures, and has relatively high requirements for surface deformation;

3. It is mostly used in road tunnels with relatively large cross-sectional dimensions;

4. The pipe curtain method can choose different specific construction methods according to different strata, surrounding environment and section size, that is, the pipe curtain method can derive many different pipe curtain construction methods;

5. The pipe jacking method should be adopted in the construction of the pipe curtain, because the pipe jacking method can meet the minimum surface deformation and high attitude control accuracy.

The scope of application of the pipe curtain construction method is relatively wide. Judging from the existing engineering examples in foreign countries, the pipe curtain construction method is suitable for various strata such as backfill, sand, clay, and rock formations, and has broad application prospects.

In recent years, there have been more and more applications of the tube curtain method in China, and some improvements have been made. The "New Tubular Roof Method" (NTR construction method) has appeared, and some relevant technical personnel call it "tube curtain pre-construction method". . Its main technical route is: using more traditional pipe jacking technology or shield technology to push or pull a cluster of large-diameter steel pipes into the formation, carry out construction in the inner body of the large-diameter steel pipes, and connect them to form the outer contour of the underground structure as expected in the design. , and then excavate the internal strata of the structure under the protection of the formed structure, and construct the internal structure.

Since the large-diameter pipe curtain forms a large-rigidity temporary support structure, it can reduce the surface deformation caused by excavation and avoid the impact on surrounding buildings. For projects with shallow buried large-section soft soil, dense buildings, and high environmental protection requirements, It has incomparable advantages.

The horizontal rotary grouting pile uses a high-pressure pump as the power source, and sprays the prepared slurry into the soil through the drill pipe and nozzle of the horizontal drilling rig. While rotating and advancing and retreating, the soil is cut, and the soil particles are forced to mix with the slurry. After the grout is solidified, a horizontal cylindrical cement-soil consolidation body is formed, that is, the horizontal jet grouting pile, which can significantly improve the strength and structural properties of the soil. Form a closed horizontal jet grouting curtain body, which plays the role of preventing quicksand, anti-slip, anti-seepage, anti-collapse and preventing ground subsidence caused by excessive water loss due to tunnel excavation.

Functions of horizontal jet grouting piles: 1. Provide arch protection for tunnel excavation; 2. Reduce the permeability of rock and soil or seal water at the full section; 3. Improve the strength of rock and soil; 4. Stabilize the tunnel face and reduce tunnel out of shape.

The scope of application of horizontal jet grouting piles: 1. Soft strata, especially water-rich soft and soft strata, such as: silt, sand, soil or a combination of several of them; 2. Special strata: fault fracture zone, landslide deposits, etc.

The advantages of horizontal rotary grouting piles: low cost, high efficiency, good effect, controllable and reliable.

1. Controllability: the area within the scope of action is more uniformly reinforced;

2. Arching: the combination of multiple horizontal jet grouting piles can form an arched structure;

3. Water sealing: it can seal water in all directions (360 degrees);

4. High strength: Destroy and mix or replace the original formation, and the consolidated body has high strength.

As shown in Figure 7, the construction steps of using the pipe-curtain rotary grouting pile support structure to build the underground structure are as follows:

1. Construct pipe jacking working well and receiving well;

2. Steel pipe jacking, the jacking sequence is symmetrical from bottom to top based on the central axis of the cross section;

Note: Steel pipe laying methods include: fixed (guided) drilling method, horizontal auger drilling method, pipe ramming method, pipe jacking method, micro pipe jacking method/micro tunnel construction method, the most commonly used is pipe jacking method.

3. For the construction of horizontal jet grouting piles between steel pipes, the number of horizontal jet grouting piles is determined by the designed steel pipe spacing.

4. Fill the steel pipe with concrete as needed.

5. Excavate the portal 3 in the support structure of the pipe curtain rotary grouting pile, and support it while excavating.

6. Construct the internal structure section by section, and gradually remove the internal support of the pipe-curtain rotary grouting pile support structure, and finally form a complete underground structure.

The construction of the underground structure under the protection of the pipe curtain rotary grouting pile support structure can adopt the excavation scheme, or the box culvert jacking scheme, etc.

1. Construction scheme and process flow of pipe curtain steel pipe jacking project

(1) Situation of pipe curtain steel pipe

The diameter of the pipe curtain steel pipe can usually be 0.3m-2m, and a larger diameter can also be selected according to the specific engineering situation.

(2) Soil reinforcement

The soil at the opening of the hole can be reinforced according to the design requirements before the pipe jacking of the pipe curtain steel pipe, and the soil reinforcement can be carried out during the construction of the working well.

(3) Hole through the wall

Before going out of the hole, cut off the outer steel plate of the pre-embedded steel box, weld the water-stop steel ring to the outside of the pre-embedded steel box, and then install the water-stop rubber ring on the water-stop steel ring. When preparing to exit the hole, cut off the soil-retaining steel plate inside the steel box, and immediately push the tool head into the pre-buried hole after cleaning the sundries in the reserved hole to shorten the pause time, so that the water-stop rubber ring tightly hugs the tool head shell to play a stop water action.

When jacking the pipe through the wall, it is necessary to prevent the tool head from falling. In the initial stage of wall penetration, the weight of the tool head is only supported by two points due to the small penetration into the soil. One point is the guide rail, and the other point is the shallow soil. Therefore, when the tool head penetrates the wall, on the one hand, it must have an upward initial angle (about 5’), on the other hand, there must be a support at the lower part of the wall-piercing pipe, and the connection between the pipe section and the tool pipe, and the pipe section and the pipe section should be strengthened. In addition, the advancement of the tool pipe must be rapid, so as not to expose the soil in the wall pipe for too long.

(4) Normal jacking

After the pipe exits the hole successfully, start normal jacking. While the pipe joint is advancing, the large cutter head of the pipe jacking machine cuts the front soil and discharges it. Through the pipe joints, the pipe jacking machine is pushed forward one by one, and finally reaches the receiving well, forming a whole section of passage.

(5) Longitudinal joint of pipe curtain steel pipe

The joint strengthens the end of the pipe by welding the annular and vertical stiffeners to increase its rigidity, and connects bolts to the reinforced annular stiffeners to limit and fix them during the construction process. Set two neoprene sealing rings on the socket for waterproofing. The joint must have the ability to adapt to a certain corner.

(6) Enter the receiving well

After the pipe jacking machine approaches the receiving well and reaches the soil reinforcement range, the jacking speed should be slowed down so that the pipe jacking machine can slowly cut the soil to form a relatively complete water stop. The specific position of the outlet of the pipe jacking machine is determined by measuring, and the concrete retaining wall at the position of the tool head of the receiving well is chiseled off. When the pipe jacking machine enters the side of the receiving well, the pipe jacking machine should quickly jack up until the pipe jacking machine is completely pushed out of the receiving well.

(7) Pipe curtain mud replacement

After the pipe curtain jacking is completed, in order to prevent the hysteresis settlement of the pipe curtain, the thixotropic mud during the jacking process will be replaced according to the design requirements. The replacement is carried out by using the system and pipeline of pressure-injected thixotropic mud. Injection sequence: from the first tube to the rear.

(8) Pipe curtain concrete pouring and filling

After the pipe curtain jacking is completed, micro-expansion concrete is used for filling. After construction, hammering and ultrasonic testing are used to detect the degree of concrete density and whether it is closely attached to the steel pipe.

(9) Tube curtain lubrication and drag reduction

Bentonite thixotropic mud is injected into the annular space between the pipeline and the surrounding soil layer to reduce the frictional resistance between the jacking pipeline and the formation. The grouting is divided into three parts, the tail synchronous grouting, the grouting along the pipeline and the grouting at the hole. The basic components of thixotropic mud are composed of bentonite and water. In addition, according to different soils, different polymer admixtures are added to adjust the performance of the mud to meet the requirements of use.

(10) Construction process of pipe curtain steel pipe jacking

The construction process of pipe-curtain steel pipe jacking is shown in Figure 8. Construction preparation-pipe joint advancement-trajectory adjustment-pipe joint reception-pipe jacking concrete pouring, in which, the pipe joint processing and downhole are carried out before the pipe joint is advanced, the trajectory adjustment is by external lubrication grouting of the pipe joint, and the pipe jacking concrete pouring is through Concrete transportation and pump pipe installation are realized by reinforcement, and at the same time, real-time conditions are observed through the air outlet when pipe jacking concrete is poured.

2. Construction scheme and process flow of horizontal directional drilling (pipe dragging) of pipe curtain steel pipe

(1) Measurement positioning

According to the measurement reference point provided, carry out the lofting work of the steel pipe of the pipe curtain according to the requirements of the design drawings. On the wall of the working well and the receiving well, accurately measure and release the position of each copper pipe of the pipe curtain, and use paint to mark it clearly. The measurement and stakeout need to be reviewed before entering the next process of construction.

(2) Drilling positioning

According to the measurement marks, on the walls of the working well and the receiving well, use water drills to drill the position of each steel pipe in the pipe screen to locate the position of each steel pipe, and respectively code the sequence numbers in the working well and the receiving well.

(3) lead hole

Lift the horizontal directional drilling machine down into the working well and install it in place. The drill pipe starts to lead the hole from the opening of the working well wall, and the drill bit introduces the hole into the receiving well, and drills out from the corresponding numbered hole of the receiving well.

(4) Reaming

Remove the drill bit, install and connect the reamer on the drill pipe, the drill pipe starts to pull back, and the reamer is dragged from the opening of the receiving well to the working well, and the reaming is completed.

(5) drag tube

Put the pipe curtain steel pipe into the receiving well, connect the front end with the drill pipe, and drag the drill pipe and the connected steel pipe back by the horizontal directional drilling rig, and drag the front end of the steel pipe to the working well.

Due to the limited space in the receiving well, the steel pipes need to be connected in sections in the receiving well, and the joints are welded.

When the steel pipe is dragged from the receiving well to the working well, underground sediment will enter the steel pipe from the front end of the steel pipe, and a high-pressure water pipe (diameter Hoses) are used to flush the sediment with high-pressure water and flow it into the receiving well for treatment.

Repeat (3)-(5) procedures to complete the construction of all pipe curtain steel pipes.

3. Construction plan and technological process of horizontal rotary grouting pile

The construction process of horizontal jet grouting piles is shown in Figure 9:

(1) Construction preparation

Carefully check whether the drilling rig and high-pressure grouting pump are running normally, and whether the drilling tools and tools are complete. Measure and set out the pile position, measure and set out the line on both sides of the tunnel to determine two identical mileage points, the tunnel axis, measure and mark the tunnel excavation contour line on the tunnel face, measure and determine the pile position, and compile each Stake number, make a good pile position mark with steel bars.

(2) Installation of drilling rig and high pressure pump

Level the working platform, lay the track, install the column, and dig the drainage ditch. Specifications of steel backing plate: length × width = 250mm × 250mm, expansion bolt diameter: The steel backing plate and the foundation should be firmly fixed and the strength should be high. The leveling error of the H-shaped steel rail is less than 3mm, the square error of the chassis diagonal line is ±3mm, the diagonal tension bars need to be tightened, the cross tension is basically equal, and the diagonal error of the four columns is ±5mm. Tighten the slips of the lifting system to strengthen the integrity; the installation site of the high-pressure pump should be flat and hardened, the installation should be stable, and the pipeline should be installed neatly; after the equipment is installed, adjust the angle and orientation of the drilling rig according to the technical disclosure, and align the holes Position, hole position error is controlled within ±5mm.

(3) Preparation of slurry

Prepare cement slurry according to the ratio required by the construction plan and technical disclosure. The ratio of water: cement is required to be 1:1. During the slurry making process, the specific gravity of the slurry should be measured at any time. The slurry should be mixed with a high-speed mixer. The mixed slurry must be continuous and uniform. The time is not less than 3 minutes, and the use time of one stirring is also controlled within 4 hours, and a test block test is required for the slurry.

(4) drilling

① use When the drill bit is drilled, a diameter of The orifice pipe with a length of 1m is buried in the drilled hole, and the orifice pipe is exposed for 0.5m, and the surrounding of the orifice pipe is sealed with instant cement. implanted in palm 4 steel bars, consolidated with anchoring agent, welded firmly with the orifice pipe, and adjust the drilling rig to the hole position, send the pilot drill bit and the first drill pipe into the hole, and install the sealing device.

② The drilling rig pressure shall not exceed 2.0MPa.

③The inclination should be measured once every 3m of drilling, and the inclination measurement records should be made. The deviation of the inclination angle of each measurement should not exceed 3%. The pilot bit is the key to correcting the deviation.

(5) High pressure spraying

After drilling to the design depth, adjust the position of the nozzle, close the waterway, open the slurry channel, gradually increase the slurry pressure to a pressure above 10MPa, rotate the nozzle at the front of the drill bit by 90 degrees through the slurry pressure, protrude from the drill bit and stand upright. Check whether the pump pressure reading meets the design requirements (35-40MPa), stay for a certain period of time during the high-pressure grouting at the bottom of the hole, and then slowly pull out the drill pipe. Pull back the 0.3m drill pipe every time it is pulled out 0.6m, and at the same time, the high-pressure rotary spray. Pay attention to the change of the pump pressure. When the pump pressure is too low, the machine should be notified in time to stop spraying, and the high-pressure rotary spraying should be resumed after finding out the cause.

(6) Sealing

When the grout reaches 0.5m from the face of the orifice, stop the grouting, turn off the high-pressure pump, pull the nozzle out with a special pull rod, remove the sealing device at the outermost end of the orifice pipe, close the circulating fluid outlet, and quickly pull out the drill pipe and the drill bit, close the large ball valve, and inject instant setting cement slurry (or cement slurry mixed with water glass and quick-setting agent) from the entrance of the sealing slurry to prevent the slurry from leaking.

(7) Cleaning pipes and equipment

After the construction of each pile, the pipeline and equipment should be flushed with clean water and high pressure to ensure that no residue is left in the pipeline, and then moved to the next pile after cleaning.

(8) Precautions for construction

①The construction process of the pile body should be continuous without interruption to prevent broken piles and short piles. When grouting, connect, unload and change pipes quickly to prevent holes from collapsing and plugging. If the machine stops for 30-60 minutes due to mechanical failure or other reasons, the spraying should be repeated for 1m, and if it exceeds 1h, it should be treated as a broken pile and the pile should be re-drilled. It is strictly forbidden to carry out the rotary spraying operation when the design depth is not reached and the rotary spraying machine is not full, and the drilling depth and rotary spraying speed are strictly controlled.

②Conscientiously do a good job in the measurement of slurry, record the cumulative amount of slurry injected, and strictly prohibit the use of slurry with inaccurate mixing ratios.

③ If there is slurry during the spraying process, the slurry output should be blocked from the orifice in time if the slurry output is small. If the slurry output is large, it should be considered to add an accelerator to the slurry, and control the spraying amount and spraying speed , Be careful not to let the waste slurry gather or flow through the bottom of the excavation face, so as not to soften the bottom strata.

④ The angle of the pile shall be controlled according to the angle of the pipe curtain steel pipe of this section of the line, and the construction accuracy shall be controlled within the range of ±3‰.

Although the specific implementation of the utility model has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the utility model. Those skilled in the art should understand that on the basis of the technical solution of the utility model, those skilled in the art do not need to Various modifications or deformations that can be made with creative efforts are still within the protection scope of the present utility model.

Claims (8)

1. A pipe curtain jet grouting pile support structure is characterized in that it comprises some pipe curtain steel pipes, at least one horizontal jet grouting pile is arranged between every two pipe curtain steel pipes, and the pipe curtain steel pipes and the horizontal jet grouting piles The edges of the pipes are in close contact, and the pipe-curtain steel pipes are combined with the horizontal jet grouting piles to form a common support force system. 2. A pipe curtain jet grouting pile support structure is characterized in that it comprises some pipe curtain steel pipes, at least one horizontal jet grouting pile is arranged between every two pipe curtain steel pipes, and the pipe curtain steel pipes and the horizontal jet grouting piles The edges of the pipes are in close contact, and part of the pipe-curtain steel pipes are filled with concrete, and the pipe-curtain steel pipes and horizontal jet grouted piles are combined to form a common support force system. 3. The pipe curtain jet grouting pile support structure as claimed in claim 2, characterized in that the pipe curtain steel pipes filled with concrete and the pipe curtain steel pipes not filled with concrete are arranged at intervals. 4. A pipe curtain jet grouting pile support structure, including several pipe curtain steel pipes, at least one horizontal jet grouting pile is arranged between every two pipe curtain steel pipes, and the edges of the pipe curtain steel pipes and the horizontal jet grouting piles are in close contact , the pipe-curtain steel pipes are filled with concrete, and the pipe-curtain steel pipes and horizontal jet grouting piles are combined together to form a common supporting stress system. 5. The pipe curtain jet grouting pile support structure as claimed in claim 1, 2 or 4, characterized in that, two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and every two adjacent The edges of the horizontal jet grouting piles are in close contact. 6. The pipe curtain jet grouting pile support structure as claimed in claim 1, 2 or 4, wherein more than two adjacent horizontal jet grouting piles are arranged between every two pipe curtain steel pipes, and each The edges of two adjacent horizontal jet grouting piles are in close contact. 7. The pipe curtain rotary grouting pile support structure according to claim 1, 2 or 4, characterized in that the diameter of the pipe curtain steel pipe is 0.3m-2m. 8. The pipe curtain jet grouting pile support structure according to claim 1, 2 or 4, characterized in that, the shape of the pipe curtain jet spray pile support structure is arranged in a circular, rectangular or other arbitrary shape.