Self-driven high polymer grouting drill bit suitable for hard soil layer and grouting method of self-driven high polymer grouting drill bit

Abstract

The invention discloses a self-driven high polymer grouting drill bit suitable for a hard soil layer and a grouting method of the self-driven high polymer grouting drill bit. The grouting drill bit comprises a conical spiral drill rod with a spiral groove in the surface, and the tail of the conical spiral drill rod is rotationally connected with a slurry inlet; a conical grouting channel and a circular tube type grouting channel which are communicated with each other are coaxially arranged in the conical spiral drill rod, and the conical grouting channel is communicated with the slurry inlet; slurry wheel blades are fixedly arranged in the conical grouting channel and rotate under the driving of slurry with certain pressure, so that the conical spiral drill rod rotationally penetrates into a soil body; a grout outlet communicated with the circular pipe type grouting channel is formed in the head of the conical spiral drill rod. According to the invention, grouting plugging can be realized more easily and quickly in a hard soil layer or a deep soil layer; the drill bit is driven to rotate and penetrate through slurry through flowing, direct grouting can be conducted after drilling and penetrating are conducted, and the construction efficiency is high; in the construction process, breaking or damage is not likely to happen, and meanwhile the construction and maintenance cost is reduced.

Description

Technical Field

[0001] The invention relates to grouting equipment, in particular to a self-driven polymer grouting drill bit suitable for hard soil layers and a grouting method thereof. Background Art

[0002] During the polymer grouting construction process, the grouting needle needs to be inserted into the soil layer. Since the shallow soil has low penetration resistance and low soil pressure, the grouting needle is relatively easy to insert and remove. For deep soil, it is necessary to first drill to the predetermined depth, drive in waterstop nails, and align the grouting needle with the waterstop nails to complete the grouting. However, for hard soil, there are often problems such as difficulty in drilling, difficulty in inserting waterstop nails or grouting needles, or easy breakage during the insertion or removal process. In order to ensure the drilling depth and drill bit hardness, higher strength materials are usually required, which leads to a significant increase in construction costs. Summary of the Invention

[0003] Purpose of the invention: The first purpose of the present invention is to provide a self-driven polymer grouting drill bit suitable for hard soil layers with high grouting efficiency, high reliability and low cost; the second purpose of the present invention is to provide a grouting method for the self-driven polymer grouting drill bit.

[0004] Technical solution: The present invention provides a self-driven polymer grouting drill bit suitable for hard soil layers, comprising a conical spiral drill rod with spiral grooves on the surface, the tail of the conical spiral drill rod being rotatably connected to a slurry inlet through a high-strength bearing, and the slurry inlet being connected to a grouting machine; a conical grouting channel and a circular tubular grouting channel are coaxially arranged inside the conical spiral drill rod, and the conical grouting channel is connected to the slurry inlet; a paddle wheel blade is provided in the conical grouting channel, and the flange of the paddle wheel blade is rigidly connected to the inner wall of the conical grouting channel. The paddle wheel blade rotates under the drive of slurry at a certain pressure, so that the conical spiral drill rod rotates and penetrates the soil; the head of the conical spiral drill rod is provided with a slurry outlet connected to the circular tubular grouting channel.

[0005] Furthermore, there are multiple paddle wheel blades, which are arranged longitudinally along the conical grouting channel, and the spacing between adjacent paddle wheel blades gradually increases from the tail to the head of the conical auger rod, so that the torque of the conical auger rod is uniform during rotation.

[0006] Furthermore, the land length f, land length B and helix angle β of the tapered spiral drill rod are determined according to the diameter d of the conical section, where f = 0.1 (d - 0.01), B = 0.55d, and β = arccos (B / d (0.8 + f)).

[0007] By adjusting the geometric parameters of the tapered spiral drill rod according to the diameter of the conical section, the grouting drill bit can maintain a high cutting force at different penetration distances. Compared with the scheme whose parameters do not change with the diameter of the conical section, the variable parameter scheme can effectively reduce the penetration resistance by 25% to 30%, especially in dense sand layers. The cutting force of a drill bit with constant parameters will change during the penetration process, which may cause the drill bit to become stuck or drill in vain. The variable parameter design can maintain the optimal cutting force, allowing soil particles to fully disperse and flow, and reducing the phenomenon of drill bit clogging.

[0008] Furthermore, the cone angle of the conical spiral drill rod is 3° to 7°, which is determined according to different formation conditions.

[0009] Furthermore, the conical spiral drill rod is made of aluminum alloy and the surface is coated with an anti-corrosion layer.

[0010] High-strength aluminum alloy is suitable for applications in hard soil formations, and the coating design protects against highly corrosive environments such as water-rich formations, extending the drill bit's service life. The surface coating further reduces the need for long-term maintenance, reducing maintenance costs by nearly 35% compared to traditional grouting needle designs.

[0011] Furthermore, the slurry outlet is cylindrical and rigidly connected to the head of the conical spiral drill rod; a plurality of slurry outlet holes are evenly distributed on the circumferential side of the slurry outlet.

[0012] This invention utilizes the rotation of a tapered spiral drill rod to drive the slurry outlet, achieving lateral slurry jetting. Compared to traditional static slurry jetting, slurry jetting facilitates even slurry distribution over a wider range. Compared to vertical drill outlets, which can be blocked by improper insertion and result in difficult slurry discharge, lateral multi-hole slurry jetting reduces the risk of single-hole clogging and improves the operability of deep grouting with the drill bit.

[0013] Furthermore, the bottom of the slurry outlet has a conical tip.

[0014] Furthermore, the bottom of the slurry inlet is conical, and the taper is 35° to 55°.

[0015] Furthermore, the conical grouting channel, the conical spiral drill rod and the circular tube grouting channel are pressed and formed by an integrated mold.

[0016] The grouting method of the self-driven polymer grouting drill bit of the present invention comprises:

[0017] (1) Connect the grouting drill bit to the grouting machine and adjust the grouting pressure according to the on-site geological conditions. The grouting pressure setting range is greater than the active soil pressure plus water pressure and less than the passive soil pressure;

[0018] (2) Insert the grouting drill bit into the shallow part of the soil layer, turn on the grouting machine, and inject the polymer slurry into the grouting drill bit, so that the conical spiral drill rod (4) rotates to drill the soil, and the grouting drill bit continues to grout after reaching the grouting point;

[0019] (3) As the grouting drill penetrates, adjust the grouting pressure to a suitable level. The hourly grouting volume Q is adjusted according to the penetration depth h, Q = 1.09 × 103 h 2.25 ;

[0020] (4) After grouting is completed, turn off the grouting machine and slowly pull out the grouting drill bit.

[0021] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0022] (1) The conical spiral drill rod, due to its unique structure, can improve the penetration performance and anti-destructive strength of the grouting drill bit, making it easier and faster to insert and remove grouting in hard soil layers or deep soil layers. In addition, when the grouting pressure is high or there are large cavities inside the soil, the conical spiral design can stabilize the grouting drill bit, reduce the displacement deviation of the grouting point caused by deformation, and improve the accuracy of grouting.

[0023] (2) The spiral grooves on the surface of the conical spiral drill rod can discharge the cut soil chips smoothly, thereby releasing the stress of the soil layer and helping the grouting drill bit to penetrate deep into the soil.

[0024] (3) Compared with the design of separate drill bit and grouting needle, the present invention can directly grout after drilling and penetration, which has higher construction efficiency. Compared with the single grouting needle design, the present invention overcomes its limitation of being unsuitable for hard soil layers, and the strength of the grouting drill bit is significantly improved, avoiding the risk of breaking during the penetration and extraction process. Compared with the pre-buried water-stop nail grouting method, the water-stop nail is a disposable consumable. The present invention integrates the drill bit and the grouting needle into one design, which can greatly reduce the use of consumables, simplify the construction process, and save time and material costs. Under a certain grouting pressure, the grouting drill uses the pressure and flow rate of the slurry during injection to drive the paddle wheel blades to rotate in the conical grouting channel, thereby realizing the self-driven rotation penetration of the grouting drill. Compared with motors or other external drive forms, the failure rate of motor drive is reduced, and the grouting drill bit is not easily broken or damaged due to vibration or external force during external drive during construction, while reducing construction and maintenance costs.

[0025] (4) The grouting channel is coaxial with the conical spiral drill rod, so that the mass of the grouting drill bit is evenly distributed and the force is more uniform during rotation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic structural diagram of a self-propelled polymer grouting drill bit suitable for hard soil layers provided by an embodiment of the present invention;

[0027] Figure 2 yes Figure 1 aa section top view;

[0028] Figure 3 1 is a partial geometric structure diagram of a tapered spiral drill rod according to an embodiment of the present invention;

[0029] Figure 4 It is a structural schematic diagram of the pulp outlet in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be further described below with reference to the accompanying drawings.

[0031] Attachment Figures 1 to 4 The reference numerals in the figures are as follows:

[0032] 1. Slurry inlet; 2. High-strength bearing; 3. Conical grouting channel; 4. Conical spiral drill rod; 5. Paddle wheel blades; 6. Circular tube grouting channel; 7. Slurry outlet; 8. Slurry outlet hole; 9. Conical tip.

[0033] like Figure 1 As shown, an embodiment of the present invention provides a self-driven polymer grouting drill bit suitable for hard soil layers, including a slurry inlet 1, a tapered spiral drill rod 4 and a slurry outlet 7.

[0034] The slurry inlet 1 is rotatably connected to the rear end of the tapered auger rod 4 via a high-strength bearing 2. The high-strength bearing 2 ensures smooth relative rotation between the tapered auger rod 4 and the slurry inlet 1, preventing torque imbalance in the grouting drill bit and enabling the handling of hard soil layers with varying conditions. The slurry inlet 1 is connected to the grouting machine via a high-pressure pipe, which in turn is connected to the slurry storage tank. Slurry is injected into the slurry inlet 1 under pressure regulated by the grouting machine. In this embodiment, the slurry inlet 1 has a conical bottom with a 45° taper, ensuring uniform injection of slurry into the soil layer.

[0035] The tapered auger rod 4 has a conical structure, facilitating the initial penetration of the grouting drill bit into the shallow soil. Spiral grooves are distributed on the surface of the tapered auger rod 4 to facilitate the removal of cut soil debris, further facilitating the penetration of the tapered auger rod 4 into the soil. In this embodiment, the tapered auger rod 4 is made of aluminum alloy and coated with an anti-corrosion coating. The cone angle of the tapered auger rod 4 ranges from 3° to 7°, depending on the different geological conditions. The total length of the tapered auger rod 4 is approximately 2 meters.

[0036] Combine Figure 3 The land length f, land length B and helix angle β of the tapered spiral drill rod 4 are determined according to the diameter d of the conical section, where f = 0.1 (d-0.01), B = 0.55d, and β = arccos (B / d (0.8+f)).

[0037] A conical grouting channel 3 and a circular tubular grouting channel 6 are coaxially disposed within the conical auger rod 4, wherein the conical grouting channel 3 is connected to the grouting inlet 1. The conical grouting channel 3, the conical auger rod 4, and the circular tubular grouting channel 6 are formed by compression molding using an integrated mold, which significantly improves strength and drilling efficiency without affecting grouting. Because the integrated compression molded drill bit has good integrity and less stress concentration, it has a stronger ability to resist external forces in hard soil applications and can drill at higher grouting pressures and rotational speeds.

[0038] Combine Figure 2 The conical grouting channel 3 is provided with a paddle wheel blade 5. The flange of the paddle wheel blade 5 is in contact with the inner wall of the conical grouting channel 3. The slurry flows in the conical grouting channel 3 under a certain grouting pressure. When passing through the paddle wheel blade 5, due to the inclination angle of the blade, the gravity will generate a component force perpendicular to the blade when the slurry flows down along the blade angle. This component force drives the slurry blade 5 to rotate, thereby causing the conical spiral drill rod 4 to rotate and cut the soil. In this embodiment, there are multiple paddle wheel blades 5, which are arranged longitudinally along the conical grouting channel 3. Due to the conical geometric characteristics of the conical spiral drill rod 4, the rotational inertia of the tail is large and the rotational inertia of the head is small. Therefore, the spacing between adjacent paddle wheel blades 5 is gradually increased from the tail to the head of the conical spiral drill rod 4. In this way, the initial angular velocity of the tail end and the head end of the grouting drill bit during rotation can be approximately equal, so that the slurry can drive the conical spiral drill rod 4 to rotate during injection to obtain a relatively uniform torque.

[0039] The circular tubular grouting channel 6 has a pore size of 10 mm and has no paddle wheel blades 5 on its inner wall. After the slurry flows into the conical grouting channel 3 , the circular tubular grouting channel 6 can act as a buffer to maintain uniform slurry discharge.

[0040] The head of the conical spiral drill rod 4 is provided with a slurry outlet 7 connected to the circular tubular grouting channel 6. The slurry outlet 7 can eject the slurry flowing from the circular tubular grouting channel 6 laterally in a rotating multi-hole slurry outlet manner. Figure 4 Specifically, the slurry outlet 7 is cylindrical and rigidly connected to the head of the tapered auger 4, rotating with the tapered auger 4. Several slurry holes 8 are evenly distributed around the circumference of the slurry outlet 7, enabling multi-hole slurry discharge. The bottom of the slurry outlet 7 has a tapered tip 9, which facilitates penetration into the soil and reduces resistance to the slurry outlet 7's rotation.

[0041] The embodiment of the present invention further provides a grouting method for a self-driven polymer grouting drill bit according to the embodiment of the present invention, comprising:

[0042] (1) Connect the grouting drill bit to the grouting machine and adjust the grouting pressure according to the on-site geological conditions. The grouting pressure setting range is greater than the active soil pressure plus water pressure and less than the passive soil pressure;

[0043] (2) Insert the grouting drill bit into the shallow part of the soil layer, turn on the grouting machine, and inject the polymer slurry into the grouting drill bit, so that the conical spiral drill rod 4 rotates to drill the soil, and the grouting drill bit continues to grout after reaching the grouting point;

[0044] (3) As the grouting drill penetrates, adjust the grouting pressure to a suitable level. The hourly grouting volume Q is adjusted according to the penetration depth h, Q = 1.09 × 103 h 2.25 ;

[0045] (4) After grouting is completed, turn off the grouting machine and slowly pull out the grouting drill bit.

Claims

1. A self-propelled polymer grouting drill bit suitable for hard soil layers, characterized in that: The invention comprises a conical spiral drill rod (4) having a spiral groove on its surface, the tail of the conical spiral drill rod (4) being rotatably connected to a slurry inlet (1) via a high-strength bearing (2), and the slurry inlet (1) being connected to a grouting machine; a conical grouting channel (3) and a circular tubular grouting channel (6) being coaxially arranged inside the conical spiral drill rod (4), and the conical grouting channel (3) being connected to the slurry inlet (1); a paddle wheel blade (5) being arranged in the conical grouting channel (3), the flange of the paddle wheel blade (5) being rigidly connected to the inner wall of the conical grouting channel (3), and the paddle wheel blade (5) being driven by slurry of a certain pressure to rotate, so that the conical spiral drill rod (4) is rotated and penetrates into the soil; and a slurry outlet (7) being connected to the circular tubular grouting channel (6) is arranged at the head of the conical spiral drill rod (4).

2. The self-driven polymer grouting drill bit according to claim 1, characterized in that: There are multiple paddle wheel blades (5) arranged longitudinally along the conical grouting channel (3), and the spacing between adjacent paddle wheel blades (5) gradually increases from the tail end to the head end of the conical auger rod (4) to ensure uniform torque when the conical auger rod (4) rotates.

3. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The land length f, land length B and helix angle β of the tapered spiral drill rod (4) are determined according to the diameter d of the conical section, wherein f=0.1(d-0.01), B=0.55d, and β=arccos(B / d(0.8+f)).

4. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The cone angle of the conical spiral drill rod (4) is 3° to 7°, which is determined according to different formation conditions.

5. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The conical spiral drill rod (4) is made of aluminum alloy and has an anti-corrosion layer coated on its surface.

6. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The slurry outlet (7) is cylindrical and rigidly connected to the head of the conical spiral drill rod (4); a plurality of slurry outlet holes (8) are evenly distributed on the circumferential side of the slurry outlet (7).

7. The self-driven polymer grouting drill bit according to claim 6, characterized in that: The bottom of the pulp outlet (7) is provided with a conical tip (9).

8. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The bottom of the pulp inlet (1) is conical, and the taper is 35° to 55°.

9. The self-driven polymer grouting drill bit according to claim 1, characterized in that: The conical grouting channel (3), the conical spiral drill rod (4) and the circular tube grouting channel (6) are pressed and formed by an integrated mold.

10. A grouting method for a self-driven polymer grouting drill bit according to any one of claims 1 to 9, characterized in that: include: (1) Connect the grouting drill bit to the grouting machine and adjust the grouting pressure according to the on-site geological conditions. The grouting pressure setting range is greater than the active soil pressure plus water pressure and less than the passive soil pressure; (2) Insert the grouting drill bit into the shallow part of the soil layer, turn on the grouting machine, and inject the polymer slurry into the grouting drill bit, so that the conical spiral drill rod (4) rotates to drill the soil, and the grouting drill bit continues to grout after reaching the grouting point; (3) As the grouting drill penetrates, adjust the grouting pressure to a suitable level. The hourly grouting volume Q is adjusted according to the penetration depth h, Q = 1.09 × 103 h 2.25 ; (4) After grouting is completed, turn off the grouting machine and slowly pull out the grouting drill bit.

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