High-pressure jet grouting pile equipment for sedimentary rock pebble layer and construction method thereof

Abstract

The application discloses a high-pressure rotary jet grouting pile equipment for sedimentary rock pebble layer and a construction method thereof, and belongs to the field of foundation construction. The equipment comprises a caterpillar vehicle provided with guide rail columns and a mounting mechanism. A rotary chuck and a positioning mechanism are slidably arranged on the guide rail columns. A drill rod is detachably connected with a power head arranged on the rotary chuck. The positioning mechanism is used for limiting and driving a protective sleeve arranged on the drill rod. The protective sleeve is formed by sequentially connecting sleeve units at the head and tail. The mounting mechanism is used for mounting the sleeve unit to be mounted to the drill rod coaxially. The mounting mechanism comprises a base, a support frame and a hydraulic cylinder. The base is arranged above the positioning mechanism. The lower end of the support frame is rotatably arranged on the base. The upper end of the support frame is used for temporarily fixing the sleeve unit to be mounted. One end of the hydraulic cylinder is rotatably arranged on the base, and the other end is rotatably connected with the support frame. The sleeve unit can be mounted without stopping the operation, and each sleeve unit limits the drill rod, thereby ensuring the perpendicularity of the drill rod.

Description

Technical Field

[0001] This invention belongs to the field of civil engineering foundation construction, and particularly relates to a high-pressure jet grouting pile device and its construction method for sedimentary rock pebble layers. Background Technology

[0002] High-pressure jet grouting is a mature foundation treatment and reinforcement technology widely used in various soil layers. However, it faces challenges in complex strata such as sedimentary rock and pebble layers, which are typically composed of high-strength pebbles, boulders, and sedimentary rock blocks of varying degrees of cementation, characterized by a loose and uneven structure, well-developed porosity, and poor self-stability. To address the issues of easy borehole collapse, grout leakage, and difficulty in ensuring borehole verticality during high-pressure jet grouting pile construction, the industry commonly employs a "follow-the-tube drilling" technique. This involves simultaneously inserting a steel protective sleeve (casing) during drilling to provide immediate support to the borehole wall.

[0003] Currently, the protective sleeves used in most engineering practices are integral, complete cylindrical units. The standard installation procedure is as follows: using a specialized drilling rig (such as a down-the-hole hammer drill or a rotary drill equipped with a casing drive), drilling to a certain depth is performed. Drilling is then completely stopped, the drill head is removed, and the individual casing sections are lifted to the borehole opening using on-site hoisting equipment (such as a crane). The casing is then aligned and lowered to the bottom of the borehole or connected to the previous section. Finally, the drill head is reinstalled, and drilling resumes. This process is repeated until the designed depth is reached. This method has the following significant problems: each installation of the next casing section requires a complete shutdown of the drilling rig for hoisting, alignment, and connection—a complex and time-consuming process. In extremely loose gravel layers, the borehole wall is highly susceptible to collapse during the short period when the drill bit is stationary and the mud or airflow is lost, leading to blockage of the drilled section and even accidents such as "drill bit burial" or "rod entrapment," making it impossible to continue construction smoothly. Furthermore, it relies heavily on large hoisting equipment, making it difficult to implement in space-constrained urban areas, areas with dense pipelines, or mountainous terrain. The transportation and transfer of the entire casing are also extremely inconvenient. In addition, as the drilling deepens, the drill rod becomes more flexible and will bend within the limited gap inside the casing. The slight misalignment error between the upper and lower casings will be amplified step by step, eventually causing the bottom of the hole to deviate significantly from the designed pile position. Summary of the Invention

[0004] The purpose of this invention is to provide a high-pressure jet grouting pile device and its construction method for sedimentary rock pebble layers in order to solve the problems in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a high-pressure jet grouting pile device for sedimentary rock pebble layers, comprising a tracked vehicle, a guide rail column mounted on the tracked vehicle, a rotary chuck and a positioning mechanism slidably mounted on the guide rail column, the rotary chuck being positioned above the positioning mechanism, a power head for driving the drill rod to rotate mounted on the rotary chuck, the top end of the drill rod being detachably connected to the power head, the bottom end of the drill rod being detachably connected to the drill bit, a protective sleeve being fitted over the drill rod, the positioning mechanism being used to limit and drive the protective sleeve, the connecting shaft of the drill bit being rotatably connected to the bottom end of the protective sleeve, the protective sleeve being formed by sequentially connecting sleeve units end to end, the sleeve units being connected by means of... The connector is detachably connected, and the sleeve unit is formed by detachably splicing a first arc plate and a second arc plate to form a cylindrical structure; it also includes an installation mechanism, which is used to rotate the first arc plate to be installed from a horizontal or inclined state to a vertical state and coaxial with the drill rod. There are two installation mechanisms, which are symmetrical about the drill rod. The installation mechanism includes a base, a support frame and a hydraulic cylinder. The base is located above the positioning mechanism. The lower end of the support frame is rotatably mounted on the base. The upper end of the support frame is used to temporarily fix the first arc plate to be installed. The tail end of the cylinder of the hydraulic cylinder is rotatably mounted on the base. The end of the piston rod of the hydraulic cylinder is rotatably connected to the support frame.

[0006] As a further description of the above technical solution: the main body of the positioning mechanism is a guide support frame, which is slidably mounted on the guide rail column. The guide support frame forms a U-shaped limiting notch, and the protective sleeve is adapted to the U-shaped limiting notch. A clamping assembly is provided inside the guide support frame. The clamping assembly includes two arc-shaped clamping plates and two hydraulic cylinders. The two arc-shaped clamping plates are arranged opposite to each other, and the hydraulic cylinders are used to adjust the clamping / non-clamping state of the two arc-shaped clamping plates on the protective sleeve.

[0007] As a further description of the above technical solution: the connecting member is an arc-shaped member, the arc-shaped member is an arc segment with a central angle of less than 360°, the opening of the arc-shaped member is larger than the diameter of the drill rod, the inner diameter of the arc-shaped member is larger than the outer diameter of the drill rod, the outer diameter of the arc-shaped member is equal to the outer diameter of the sleeve unit, the upper and lower end faces of the arc-shaped member are provided with limiting flanges, the outer diameter of the limiting flanges is equal to the inner diameter of the protective sleeve, a compensation block is provided in the middle of one end of the first arc plate, the compensation block is adapted to the opening of the arc-shaped member, the sleeve unit is connected to the arc-shaped member by bolts, and the first arc plate is connected to the second arc plate by bolts.

[0008] As a further description of the above technical solution: a limiting plate is provided inside the arc-shaped component, and a U-shaped notch is provided on the limiting plate. The U-shaped notch corresponds to the opening of the arc-shaped component. The U-shaped notch is formed by recessing inward from the outer edge of the limiting plate, and the deepest part of the U-shaped notch is an arc segment coaxial with the limiting plate. The arc segment is adapted to the drill rod.

[0009] As a further description of the above technical solution: rollers are rotatably provided at equal intervals on the inner side of the arc segment, the rotation axis of the rollers is parallel to the axis of the limiting plate, and the rollers are in contact with the side of the drill rod.

[0010] As a further description of the above technical solution: The first arc plate has a pair of first mounting notches; the base has a rotating seat with an oblong hole; the support frame includes an arc-shaped positioning plate, a telescopic rod, and a guide assembly; the arc-shaped positioning plate has a positioning protrusion on its side facing the first arc plate, the positioning protrusion corresponding one-to-one with the first mounting notch; the telescopic rod consists of a sleeve and a connecting rod; one end of the sleeve has a mounting hole along its length, the connecting rod slides within the mounting hole; an adjusting spring is installed inside the sleeve, located between the bottom of the mounting hole and the end of the connecting rod; a rotating shaft is installed at the end of the sleeve away from the connecting rod, the rotating shaft being connected to the oblong hole... The connecting rod is fixedly connected to the arc-shaped positioning plate at one end away from the sleeve, and the piston rod of the hydraulic cylinder is rotatably connected to the sleeve. The guiding assembly includes a guide plate and an elastic guide head. The guide plate is located in front of or behind the support frame and is fixedly mounted on the base. A guide groove is provided on the guide plate. The elastic guide head is fixedly mounted on the connecting rod and is slidably mounted in the guide groove. The guide groove includes a lifting arc-shaped groove, a lowering groove, and a resetting groove that are connected end to end. The resetting groove includes a horizontal section and an arc-shaped section. The horizontal section is located at the beginning of the resetting groove and is parallel to the waist-shaped hole and has the same length.

[0011] As a further description of the above technical solution: the depth of the lifting arc-shaped groove gradually decreases from its first end to its last end, the depth of the last end of the lifting arc-shaped groove is equal to the depth of the positioning groove and the reset groove, and there is a height difference between the depth of the first end of the lifting arc-shaped groove and the depth of the last end of the reset groove.

[0012] As a further description of the above technical solution: the bottom end of the protective sleeve is provided with a connecting ring, the connecting ring is provided with a connecting flange, the outer diameter of the connecting flange is equal to the inner diameter of the protective sleeve, the outer diameter of the connecting ring is equal to the outer diameter of the protective sleeve, the flange is connected to the sleeve unit by bolts, a bearing is provided inside the connecting ring, and the connecting shaft of the drill bit is adapted to the bearing.

[0013] A method for constructing high-pressure jet grouting piles in sedimentary rock pebble layers, employing the aforementioned high-pressure jet grouting pile equipment for sedimentary rock pebble layers, includes the following steps: Step 1: Move the tracked vehicle to the designated hole position and adjust the guide rail column to be directly above the designated hole position; Step 2: Connect the upper end of the first drill rod to the power head, the lower end of the first drill rod to the drill bit, and the first sleeve unit to the connecting shaft of the drill bit. Fix the first sleeve unit to the positioning mechanism and start drilling. The positioning mechanism and the rotary chuck are fed synchronously. Step 3: After drilling half the length of the sleeve unit, install the next sleeve unit through the installation mechanism without stopping the machine. The next sleeve unit is connected to the previous sleeve unit through a connector. Then, the positioning mechanism releases the clamp on the previous sleeve unit and moves upward to clamp the next sleeve unit. After drilling each sleeve unit length, install the next sleeve unit through the installation mechanism. After drilling three-quarters of the length of the drill rod, stop the machine to install the next drill rod. Step 4: After drilling to the set depth, simultaneously pull up the protective sleeve, drill bit and drill rod. After pulling up the protective sleeve, remove each sleeve unit from top to bottom in sequence. At the same time, the drill bit continuously rotates and sprays grout into the borehole until the borehole opening is reached, thus completing the jet grouting pile operation.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: (1) In the process of jet grouting pile operation, the sleeve unit of the protective sleeve can be installed continuously and quickly while the drill rod is rotating and drilling. The sleeve unit is designed as a unit spliced ​​on site by the first arc plate and the second arc plate, and the units are connected by connectors with limiting flanges and roller stabilizers. This realizes the lightweight and modularity of the sleeve unit, making it possible to install in a narrow space without the need for large hoisting equipment, laying the foundation for non-stop construction. At the same time, the openings of the adjacent connectors are oriented differently, thereby forming a circumferential limit on the drill rod and ensuring the drilling verticality of the drill rod.

[0015] (2) The inner wall of the protective sleeve is supported by a connector every unit length along its axial direction, which makes the support stiffness of the protective sleeve stable, the protective sleeve as a whole is not easily deformed, effectively avoids hole collapse, and ensures smooth drilling and drilling and jet grouting.

[0016] (3) When installing the sleeve unit, the installation mechanism can install the first arc plate into place and reset smoothly under the action of the hydraulic cylinder and the guide component. The structure is ingenious, the installation is fast and accurate, and the drill rod does not need to be stopped to rotate throughout the process, which greatly shortens the auxiliary time and eliminates the risk of machine shutdown and hole collapse.

[0017] (4) A hydraulically driven arc-shaped clamping plate actively grips the protective sleeve from both sides, forming a powerful "anti-torsion" and "straightening" mechanism. The pressure can be finely adjusted to actively correct the verticality. This provides active and adjustable verticality control capabilities, ensuring the straightness of the hole during long-distance drilling in complex and heterogeneous strata, and significantly improving the quality of pile formation. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention, in which the protective sleeve and the mounting mechanism are not shown; Figure 3 This is an exploded view of the sleeve unit of the present invention; Figure 4 This is a three-dimensional structural diagram of the connector of the present invention; Figure 5 This is a schematic diagram of the three-dimensional structure of the connecting ring of the present invention; Figure 6 This is a diagram showing the positional relationship between the installation mechanism, drill rod, and protective sleeve of the present invention. Figure 7 This is a perspective view showing the initial positional relationship between the base, the arc-shaped positioning plate, and the hydraulic cylinder of the mounting mechanism of the present invention. Figure 8 This is a side view of the guide plate of the present invention; Figure 9 This is a side view of the installation mechanism in its initial state according to the present invention; Figure 10 This is a schematic diagram showing the state at the end of the first stage of the installation process of the installation mechanism of the present invention on the first arc plate; Figure 11 This is a schematic diagram showing the state at the end of the second stage of the installation process of the installation mechanism of the present invention on the first arc plate; Figure 12 This is a schematic diagram of the third stage of the installation process of the installation mechanism of the present invention on the first arc plate, with the guide cap in the horizontal section of the reset groove. Figure 13 This is a schematic diagram of the third stage of the installation process of the installation mechanism of the present invention on the first arc plate, and the guide cap in a certain state in the arc segment.

[0019] Legend: 100, Tracked vehicle; 200, Guide rail column; 1, Rotary chuck; 11, Power head; 2, Guide support frame; 21, U-shaped limiting notch; 22, Arc-shaped clamping plate; 23, Hydraulic cylinder; 3, Drill rod; 4, Drill bit; 41, Connecting shaft; 5, Connecting ring; 51, Connecting flange; 52, Bearing; 6, Sleeve unit; 61, First arc plate; 611, First mounting notch; 612, First connecting hole; 613, Compensating block; 614, Second connecting hole; 62, Second arc plate; 621, First connecting lug; 622, Third connecting hole; 7, Connecting piece; 71, Second mounting notch; 72, Fourth connecting hole; 73, Limiting flange; 74, Clearance notch; 75, ... 76. Fifth connecting hole; 77. Limiting plate; 771. U-shaped notch; 772. Arc segment; 78. Roller; 8. Mounting mechanism; 81. Base; 82. Hydraulic cylinder; 83. Support frame; 84. Arc-shaped positioning plate; 841. Positioning protrusion; 85. Sleeve; 851. Rotating shaft; 86. Connecting rod; 87. Adjusting spring; 881. Guide plate; 882. Positioning rod; 883. Guide cap; 89. Rotating seat; 891. Waist-shaped hole; 892. First end; 893. Second end; 90. Lifting arc-shaped groove; 901. First end of lifting arc-shaped groove; 902. Tail end of lifting arc-shaped groove; 91. Positioning groove; 92. Reset groove; 921. Horizontal segment; 922. Arc segment. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1-13 This invention provides a technical solution for a high-pressure jet grouting pile device and its construction method for sedimentary rock pebble layers: A high-pressure jet grouting pile device for sedimentary rock pebble layers is mounted on a tracked vehicle 100 and has good mobility. The guide rail column 200 is mounted on the tracked vehicle 100 via a luffing mechanism. The luffing mechanism adjusts the angle of the guide rail column 200 to ensure it is vertical during operation. When the tracked vehicle 100 moves, the luffing mechanism adjusts the guide rail column 200 to a horizontal position for easy movement. The luffing mechanism is prior art and will not be described in detail in this application.

[0022] The guide rail column 200 is equipped with a rotary chuck 1 and a positioning mechanism that can slide synchronously or independently. The power head 11 on the rotary chuck 1 provides the torque required for drilling. The sliding of the rotary chuck 1 along the guide rail column 200 provides pressure to the drill rod 3 and drill bit 4. The lower part of the power head 11 is detachably connected to the top of the drill rod 3 via a conventional threaded or flanged interface. In this embodiment, the power head 11 and the drill rod 3 are connected by threads. The drill rod 3 uses a standard single-section length (e.g., 3 meters). When drilling deeper is required, the machine can be stopped and the drill rod 3 can be continued according to the conventional procedure. When the drill rod 3 needs to be continued, a short stop is required. Then, the top of the previous drill rod 3 is disconnected from the power head 11. The rotary chuck 1 then moves upward along the guide rail column 200 until there is sufficient space to install the next drill rod 3. The upper end of the next drill rod 3 is connected to the power head 11, and the lower end of the next drill rod 3 is connected to the upper end of the previous drill rod 3. The bottom end of the first section of drill rod 3 is connected to the drill bit 4, which is used for cutting and drilling in gravel layers or soil.

[0023] A protective sleeve is fitted around the outer periphery of the drill pipe 3. In this embodiment, the protective sleeve is not a traditional integral long cylinder, but rather composed of multiple standard-length sleeve units 6 connected section by section on-site. A positioning mechanism is slidably positioned below the rotary chuck 1. Its main body is a guide support frame 2, which is slidably mounted on the guide rail column 200 via a slider. It can slide independently or synchronously relative to the rotary chuck 1. The guide support frame 2 is U-shaped, forming a U-shaped limiting notch 21 that matches the curvature of the outer wall of the protective sleeve, providing initial radial constraint on the sleeve. A clamping assembly is installed inside the guide support frame 2. This clamping assembly includes two symmetrically arranged arc-shaped clamping plates 22, each driven by a hydraulic cylinder 23. The cylinder body of the hydraulic cylinder 23 is fixed to the guide support frame 2, and the end of the piston rod is hinged to the back of the arc-shaped clamping plate 22. When clamping is required, the two cylinders extend synchronously, pushing the arc-shaped clamping plates 22 to grip the outer wall of the protective sleeve from both sides. The inner lining of the arc-shaped clamping plate 22 can be made of a wear-resistant material with a high coefficient of friction (such as engineering plastics or rubber composite plates) to increase friction. The positioning mechanism drives the entire frame to press down through its lifting cylinder, thus simultaneously pressing the firmly clamped protective sleeve into the formation. This active and rigid clamping method not only provides downward pressure but also constitutes a powerful "anti-torsion" and "straightening" mechanism, which can effectively prevent the sleeve from rotating and can correct minor vertical deviations by finely adjusting the pressure of the cylinders on both sides.

[0024] The bottom end of the protective sleeve (the bottom end of the first sleeve unit 6) is connected to the drill bit 4 via a connecting ring 5. The upper end of the connecting ring 5 has a connecting flange 51, the outer diameter of which is equal to the inner diameter of the sleeve unit 6. The connecting flange 51 is bolted to the first sleeve unit 6. A bearing 52 is embedded inside the connecting ring 5. The connecting shaft 41 of the drill bit 4 extends and passes through the inner ring of the bearing 52. This design allows the drill bit 4 to rotate freely under the drive of the power head 11, while the huge axial reaction force generated during drilling acts on the bearing 52 through the shoulder of the connecting shaft 41, thereby transmitting the downward thrust to the connecting ring 5 and the entire protective sleeve, achieving the "following the pipe" function, while completely isolating the transmission of rotational torque to the sleeve.

[0025] The sleeve unit 6 is detachably spliced ​​from the first arc plate 61 and the second arc plate 62 to form a cylindrical structure. When the sleeve unit 6 is fitted onto the periphery of the drill rod 3, the first arc plate 61 and the second arc plate 62 are positioned on the left and right sides of the drill rod 3, respectively. The first arc plate 61 is an arc segment 772 with a central angle greater than 180 degrees. The opening of the first arc plate 61 is larger than the diameter of the drill rod 3, so that when the first arc plate 61 is installed, it can be made coaxial with the drill rod 3 through the opening of the first arc plate 61 while the drill rod 3 is rotating normally. The upper and lower outer walls of the right side of the first arc plate 61 both have first installation notches 611. The first installation notches 611 are symmetrically arranged about the front and back of the annulus where the first arc plate 61 is located. The upper, lower and middle outer walls of the left side of the first arc plate 61 also have first installation notches 611. A first connecting hole 612 is provided between the symmetrical first installation notches 611. A compensation block 613 is provided at the lower end of the first arc plate 61, and a second connecting hole 614 is provided on the compensation block 613.

[0026] The inner side of the second arc plate 62 is provided with a first connecting lug 621 at the upper end, lower end and middle. The first connecting lugs 621 are arranged in pairs and are symmetrical about the front and back of the second arc plate 62. The first connecting lugs 621 are provided with a third connecting hole 622, which corresponds one-to-one with the first connecting hole 612 on the left side of the first arc plate 61.

[0027] The sleeve units 6 are connected by connectors 7. After the upper and lower sleeve units 6 are connected, if the first arc plate 61 of the lower sleeve unit 6 is located on the left side of the drill pipe 3, then the first arc plate 61 of the upper sleeve unit 6 is located on the right side of the drill pipe 3. Similarly, if the second arc plate 62 of the lower sleeve unit 6 is located on the right side of the drill pipe 3, then the second arc plate 62 of the upper sleeve unit 6 is located on the left side of the drill pipe 3. The upper and lower sleeve units 6 are connected in this staggered manner.

[0028] When the first arc plate 61 and the second arc plate 62 are spliced ​​together, the first connecting hole 612 on the opening side of the first arc plate 61 corresponds one-to-one with the third connecting hole 622 of the first connecting lug 621 of the second arc plate 62.

[0029] The connector 7 is an arc-shaped component with a central angle of less than 360°, and the radius of its arc segment 772 is the same as the outer diameter of the protective sleeve. Both the upper and lower end faces of this arc-shaped component are provided with limiting flanges 73, the outer diameter of which is equal to the inner diameter of the protective sleeve. The connector 7 has a second mounting notch 71 at its opening, which is symmetrical about the front and back of the connector 7. A fourth connecting hole 72 is formed within each of the two second mounting notches 71. The limiting flange 73 has clearance notches 74 on both the left and right sides of its end face away from the connector 7. A second connecting lug 75 is provided on the clearance notch 74 away from the opening of the limiting flange 73, and a fifth connecting hole 76 is formed on the second connecting lug 75.

[0030] During installation, the connector 7 snaps into the joint of the upper and lower sleeve units 6. The opening of the connector 7 is adapted to the compensation block 613 below the first arc plate 61 of the upper sleeve unit 6. The second connecting hole 614 of the compensation block corresponds to the fourth connecting hole, and its shape is adapted to the gap of the opening of the connector 7. When the two arc plates are closed, the compensation block 613 fills the gap, forming a complete annular support together with the connector 7. The upper and lower limiting flanges 73 of the connector 7 are respectively inserted into the inner walls of the upper and lower sleeve units 6, which play a radial positioning role. The second connecting lug 75 of the clearance notch 74 on the limiting flange 73 is located between the two first connecting lugs 621 at the end of the second arc plate 62. The fifth connecting hole 76 is coaxial with the first connecting hole 612 and the third connecting hole 622. Then, the connector 7 is fastened to the upper and lower sleeve units 6 with bolts.

[0031] To further ensure verticality during long-distance drilling in complex formations, a limiting plate 77 is added inside the arc-shaped component of connector 7. The limiting plate 77 has a U-shaped notch 771 corresponding to the opening of the arc-shaped component, the deepest part of which is an arc segment 772 adapted to the diameter of drill pipe 3. Multiple freely rotatable rollers 78 are equidistantly installed circumferentially on the inner wall of this arc segment 772, with the axis of the rollers 78 parallel to the plane of the limiting plate 77. When the protective sleeves are connected as a whole, the staggered arrangement of the limiting plates 77 and sleeve units 6 ensures that the openings of adjacent limiting plates 77 face each other, thus creating a state that completely limits the drill pipe 3. These rollers 78 distributed at each connection point together form a continuous "bearing 52 stabilizer," contacting the outer wall of the drill pipe 3. They effectively limit the lateral swing of the drill pipe 3, guiding it to drill vertically, and convert the sliding friction of the drill pipe 3 rotation into rolling friction, significantly reducing resistance and wear.

[0032] An installation mechanism 8 is provided above the guide support frame 2. Two installation mechanisms 8 are symmetrically arranged on both sides of the top of the U-shaped frame, about the drill rod 3. Each installation mechanism 8 includes a base 81, a support frame 83, and a hydraulic cylinder 82. A rotating seat 89 is provided on the base 81, and an oblong hole 891 is opened on the rotating seat 89. The support frame 83 is composed of an arc-shaped positioning plate 84, a telescopic rod, and a guide assembly.

[0033] The arc-shaped positioning plate 84 is used to support and temporarily position the first arc plate 61. The side of the arc-shaped positioning plate 84 facing the first arc plate 61 is provided with positioning protrusions 841. The positioning protrusions 841 correspond one-to-one with the first mounting notches 611 at the upper and lower ends of the side of the first arc plate 61 away from its opening. When the first arc plate 61 is placed on the arc-shaped positioning plate 84, the opening of the first arc plate 61 faces upward.

[0034] The telescopic rod consists of a sleeve 85 and a connecting rod 86. One end of the sleeve 85 has a mounting hole along its length. The connecting rod 86 slides in the mounting hole. An adjusting spring 87 is installed inside the sleeve 85. The adjusting spring 87 is located between the bottom of the mounting hole and the end of the connecting rod 86. A rotating shaft 851 is installed at the end of the sleeve 85 away from the connecting rod 86. The rotating shaft 851 is adapted to the oblong hole 891 and can slide in the oblong hole 891 or along the length of the oblong hole 891.

[0035] The tail end of the cylinder of the hydraulic cylinder 82 is rotatably mounted on the base 81, and the end of the piston rod of the hydraulic cylinder 82 is hinged to the sleeve 85.

[0036] The guide assembly controls the movement trajectory of the arc-shaped positioning plate 84, thereby installing the first arc plate 61 into place. The guide assembly includes a guide plate 881 and an elastic guide head. The guide plate 881 is located in front of or behind the support frame 83. In this embodiment, guide plates 881 are provided in both front and rear of the support frame 83. The two guide plates 881, which are symmetrical about the support frame 83, ensure that the support frame 83 is subjected to equal force during guidance, making the guidance more stable and smooth. The guide plate 881 is fixedly mounted on the base 81. A guide groove is provided on the guide plate 881. The elastic guide head is mounted on the connecting rod 86. The position of the elastic guide head does not affect the sliding of the connecting rod 86 within the sleeve 85. The elastic guide head consists of a positioning rod 882 fixedly mounted on the connecting rod 86 and a guide cap 883 sleeved on the end of the positioning rod 882. A telescopic spring is provided between the guide cap 883 and the end of the positioning rod 882. The guide cap 883 is slidably mounted in the guide groove. The guide groove includes a series of lifting springs connected end to end. The lifting arc groove 90, the positioning groove 91, and the reset groove 92 are provided. The reset groove 92 includes a horizontal section 921 and an arc section 922. The horizontal section 921 is located at the beginning of the reset groove 92. The horizontal section 921 is parallel to the waist-shaped hole 891 and has the same length. The groove depth from the beginning 901 of the lifting arc groove to the end 902 of the lifting arc groove gradually decreases. The groove depth at the end 902 of the lifting arc groove is equal to the groove depth of the positioning groove 91 and the reset groove 92. There is a height difference between the groove depth at the beginning 901 of the lifting arc groove and the groove depth at the end of the reset groove 92.

[0037] The installation process and principle of the mounting mechanism 8 for the first arc plate 61 are as follows: Before installing the next sleeve unit 6, first install the connector 7 on the upper end of the previous sleeve unit 6, with the opening of the connector 7 facing the side where the first arc plate 61 is to be installed.

[0038] Initially, the elastic guide head on the connecting rod 86 is located at the first end 901 of the lifting arc groove, and the support frame 83 is in a retracted, i.e., tilted, state. The first arc plate 61 is temporarily positioned on the arc positioning plate 84. Since the first arc plate 61 is short and lightweight, it can be placed manually on the arc positioning plate 84 between the two guide plates 881. The first arc plate 61 is temporarily constrained by the fit between the positioning protrusion 841 and the first mounting notch 611. At this time, under the action of the adjusting spring 87, the rotating shaft 851 at the end of the sleeve 85 is located at the first end 892 of the oblong hole 891.

[0039] Phase 1: Hydraulic cylinder 82 is activated. The piston rod of hydraulic cylinder 82 extends from its cylinder barrel, driving sleeve 85 to rotate around the first end 892 of the rotating shaft 851 within the oblong hole 891. Simultaneously, the elastic guide head on connecting rod 86 moves from the first end 901 of the lifting arc groove to the last end 902 of the lifting arc groove. Due to the height difference between the groove depth of the first end 901 of the lifting arc groove and the groove depth of the last end of the reset groove 92, the elastic guide head will not enter the last end of the reset groove 92. During this process, the rotation of the telescopic rod drives the arc positioning plate 84 and the first arc plate 61 to rotate to a vertical state. In this state, the first arc plate 61 is coaxial with the connecting piece 7 and is located above the connecting piece 7. During the above process, as the first arc plate 61 rotates towards the drill rod 3, its opening corresponds to the drill rod 3, ensuring that it does not interfere with the drill rod 3 and does not affect the normal rotation of the drill rod 3.

[0040] In the second stage, when the guide cap 883 enters the first end of the lifting arc groove 90, i.e., the positioning groove 91, the hydraulic cylinder 82 is adjusted to a free state and can be extended or retracted by external force. The telescopic rod is in a vertical state. Under the gravity of the first arc plate 61 and the arc positioning plate 84, the adjusting spring 87 is compressed, and the guide cap 883 slides from the first end of the positioning groove 91 to the tail end of the positioning groove 91. During this process, the first arc plate 61 moves downward and matches the limiting flange 73 of the connector 7, and the compensation block 613 at the lower end of the first arc plate 61 enters the opening of the connector 7.

[0041] The third stage: First, the operator or auxiliary robot immediately installs the second arc plate 62 and tightens the bolts to connect the first arc plate 61 and the second arc plate 62, forming a complete sleeve unit 6. Then, the extension rod and the arc-shaped positioning plate 84 are reset by the retraction of the hydraulic cylinder 82. During this process, the guide cap 883 enters the horizontal section 921 of the first reset groove 92 and moves within the horizontal section 921. During the movement, due to the interaction between the arc-shaped positioning plate 84 and the first arc plate 61, the rotation shaft 851 at the end of the sleeve 85 moves from the first end 892 of the waist-shaped hole 891 toward the second end 893. When the positioning protrusion 841 on the arc-shaped positioning plate 84 disengages from the first installation notch 611, the guide cap 883 moves from the arc-shaped section 922 of the reset groove 92 to the first end 901 of the lifting arc-shaped groove under the action of the retraction of the hydraulic cylinder 82 and the action of the adjusting spring 87. The support frame 83 returns to the initial horizontal position, ready for the next installation. The drill rod 3 does not need to stop rotating throughout the entire process. Then the first arc plate 61 and the connector 7 are fully connected together with bolts.

[0042] Based on the above-mentioned equipment, the construction method of the present invention includes the following steps: S1: Positioning and Centering. The tracked vehicle 100 is moved to the designed pile position, and the vehicle body is leveled and finely adjusted through the hydraulic system to align the axis of the guide rail column 200 with the center of the pile.

[0043] S2: Initial Drilling. Assemble the first drill pipe section 3, drill bit 4, and first sleeve unit 6 (pre-assembled). The first sleeve unit 6 is connected to the connecting shaft 41 of the drill bit 4 via the connecting ring 5 at the bottom, and its upper part is held by the arc-shaped clamping plate 22 of the positioning mechanism. Start the power head 11 and the pressure cylinder of the positioning mechanism, and the drill bit 4 rotates to cut the formation. At the same time, the protective sleeve is pressed in synchronously, realizing casing drilling.

[0044] S3: Continuously connect the sleeve and drill pipe 3. This is a critical process.

[0045] When the first sleeve unit 6 is pressed in to about half its own length, the drill bit 4 has drilled out enough space. At this point, while the drill rod 3 continues to rotate, the installation mechanism 8 is activated. As mentioned above, it automatically flips, lifts, and precisely positions the prepared first arc plate 61 from the horizontal position to the vertical installation position.

[0046] The corresponding second arc plate 62 is quickly installed manually or with the help of auxiliary tools, and the two arc plates are fastened with bolts to form a new sleeve unit 6.

[0047] The arc-shaped clamp 22 of the positioning mechanism releases its grip on the previous sleeve section, slides upward to the upper middle part of the new sleeve section 6, re-clamps, and continues to apply pressure downward.

[0048] Repeat this "installation-connection-clamping follow-up" cycle to achieve continuous extension of the protective sleeve. During this process, when the drill rod 3 needs to be spliced, the machine can be paused briefly, and the next section of drill rod 3 can be spliced ​​at the power head 11 in the conventional manner, and then the above cycle can be continued. The installation of two adjacent sleeve units 6 does not use the same installation mechanism 8, that is, two installation mechanisms 8, one on the left and one on the right, are used alternately.

[0049] S4: Hole Formation and Jet Grouting. After drilling to the designed depth, high-pressure jet grouting is performed. The typical procedure is as follows: High-pressure cement grout is injected into the bottom of the hole through the central channel of drill rod 3. Simultaneously, the power head 11 and the positioning mechanism are raised synchronously. The drill bit 4 continues to rotate and spray during the lifting process. As the protective sleeve is pulled out synchronously, the operator can disassemble and remove the sleeve unit 6 section by section from the top. Grouting is then performed to the borehole opening, completing the single pile construction.

[0050] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention within the scope of the technology disclosed in the present invention, and all such substitutions or changes should be covered within the scope of protection of the present invention.

Claims

1. A high-pressure jet grouting pile device for sedimentary rock pebble layers, comprising a tracked vehicle (100), a guide rail column (200) provided on the tracked vehicle (100), a rotary chuck (1) and a positioning mechanism slidably provided on the guide rail column (200), the rotary chuck (1) being positioned above the positioning mechanism, a power head (11) for driving a drill rod (3) to rotate provided on the rotary chuck (1), the top end of the drill rod (3) being detachably connected to the power head (11), the bottom end of the drill rod (3) being detachably connected to a drill bit (4), a protective sleeve being provided over the drill rod (3), the positioning mechanism being used to limit and drive the protective sleeve, and the connecting shaft (41) of the drill bit (4) being rotatably connected to the bottom end of the protective sleeve, characterized in that: The protective sleeve is formed by connecting sleeve units (6) end to end in sequence. The sleeve units (6) are detachably connected by connectors (7). A connecting ring (5) is provided at the bottom of the protective sleeve. The sleeve unit (6) is formed by detachably splicing a first arc plate (61) and a second arc plate (62) to form a cylindrical structure. It also includes an installation mechanism (8), which is used to rotate the first arc plate (61) to be installed from a horizontal or inclined state to a vertical state and coaxial with the drill rod (3). There are two installation mechanisms (8), which are symmetrical about the drill rod (3). The installation mechanism (8) includes a base (81), a support frame (83) and a hydraulic cylinder (82). The base (81) is located above the positioning mechanism. The lower end of the support frame (83) is rotatably mounted on the base (81). The upper end of the support frame (83) is used to temporarily fix the first arc plate (61) to be installed. The tail end of the cylinder of the hydraulic cylinder (82) is rotatably mounted on the base (81). The end of the piston rod of the hydraulic cylinder (82) is rotatably connected to the support frame (83).

2. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 1, characterized in that: The main body of the positioning mechanism is a guide support frame (2), which is slidably mounted on the guide rail column (200). The guide support frame (2) forms a U-shaped limiting notch (21). The protective sleeve is adapted to the U-shaped limiting notch. A clamping assembly is provided inside the guide support frame (2). The clamping assembly includes two arc-shaped clamping plates (22) and two hydraulic cylinders (23). The two arc-shaped clamping plates (22) are arranged opposite to each other. The hydraulic cylinders (23) are used to adjust the clamping / non-clamping state of the two arc-shaped clamping plates (22) on the protective sleeve.

3. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 1, characterized in that: The connector (7) is an arc-shaped component with a central angle of less than 360°. The opening of the arc-shaped component is larger than the diameter of the drill rod (3). The inner diameter of the arc-shaped component is larger than the outer diameter of the drill rod (3). The outer diameter of the arc-shaped component is equal to the outer diameter of the sleeve unit (6). The upper and lower end faces of the arc-shaped component are provided with limiting flanges (73). The outer diameter of the limiting flanges (73) is equal to the inner diameter of the protective sleeve. A compensation block (613) is provided at the middle of one end of the first arc plate (61). The compensation block (613) is adapted to the opening of the arc-shaped component. The sleeve unit (6) and the arc-shaped component are connected by bolts. The first arc plate (61) and the second arc plate (62) are connected by bolts.

4. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 3, characterized in that: A limiting plate (77) is provided inside the arc-shaped component. A U-shaped notch (771) is provided on the limiting plate (77). The U-shaped notch (771) corresponds to the opening of the arc-shaped component. The U-shaped notch (771) is formed by recessing inward from the outer edge of the limiting plate (77). The deepest part of the U-shaped notch (771) is an arc segment (772) coaxial with the limiting plate (77). The arc segment (772) is adapted to the drill rod (3).

5. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 4, characterized in that: Rollers (78) are rotatably provided at equal intervals on the inner side of the arc segment (772). The rotation axis of the rollers (78) is parallel to the axis of the limiting plate (77), and the rollers (78) are in contact with the side of the drill rod (3).

6. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 1, characterized in that: The first arc plate (61) is provided with a pair of first mounting notches (611), the base (81) is provided with a rotating seat (89), the rotating seat (89) is provided with a waist-shaped hole (891), the support frame (83) includes an arc-shaped positioning plate (84), a telescopic rod and a guide assembly, the side of the arc-shaped positioning plate (84) facing the first arc plate (61) is provided with a positioning protrusion (841), the positioning protrusion (841) is paired with the first mounting notch (611) one by one. The telescopic rod consists of a sleeve (85) and a connecting rod (86). One end of the sleeve (85) has a mounting hole along its length. The connecting rod (86) slides within the mounting hole. An adjusting spring (87) is installed inside the sleeve (85), located between the bottom of the mounting hole and the end of the connecting rod (86). A rotating shaft (851) is installed at the end of the sleeve (85) away from the connecting rod (86). The rotating shaft (851) is connected to the waist-shaped hole (89). 1) Adaptation: The end of the connecting rod (86) away from the sleeve (85) is fixedly connected to the arc-shaped positioning plate (84), and the end of the piston rod of the hydraulic cylinder (82) is rotatably connected to the sleeve (85); the guide assembly includes a guide plate (881) and an elastic guide head. The guide plate (881) is disposed in front of or behind the support frame (83), and the guide plate (881) is fixedly disposed on the base (81). The guide plate (881) has a guide opening. The elastic guide head is fixedly mounted on the connecting rod (86) and slidably mounted in the guide groove. The guide groove includes a lifting arc groove (90), a positioning groove (91), and a reset groove (92) that are connected end to end. The reset groove (92) includes a horizontal section (921) and an arc section (922). The horizontal section (921) is located at the beginning of the reset groove (92). The horizontal section (921) is parallel to the waist-shaped hole (891) and has the same length.

7. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 6, characterized in that: The depth of the lifting arc groove (90) gradually decreases from its first end to its last end. The depth of the last end of the lifting arc groove (90) is equal to the depth of the positioning groove (91) and the reset groove (92). There is a height difference between the depth of the first end of the lifting arc groove (90) and the depth of the last end of the reset groove (92).

8. The high-pressure jet grouting pile equipment for sedimentary rock pebble layers according to claim 1, characterized in that: The connecting ring (5) is provided with a connecting flange (51), the outer diameter of the connecting flange (51) is equal to the inner diameter of the protective sleeve, the outer diameter of the connecting ring (5) is equal to the outer diameter of the protective sleeve, the connecting flange (51) and the sleeve unit (6) are connected by bolts, a bearing (52) is provided inside the connecting ring (5), and the connecting shaft (41) of the drill bit (4) is adapted to the bearing (52).

9. A method for constructing high-pressure jet grouting piles in sedimentary rock pebble layers, comprising a high-pressure jet grouting pile device for sedimentary rock pebble layers according to any one of claims 1-8, characterized in that: Includes the following steps: S1: Move the tracked vehicle (100) to the set hole position and adjust the guide rail column (200) to be directly above the set hole position; S2: Connect the upper end of the first section of drill rod (3) to the power head (11), connect the lower end of the first section of drill rod (3) to the drill bit (4), connect the first section of sleeve unit (6) to the connecting shaft (41) of the drill bit (4), fix the first section of sleeve unit (6) to the positioning mechanism, start drilling, and feed the positioning mechanism and the rotary chuck (1) synchronously. S3: After drilling half the length of the sleeve unit (6), install the next sleeve unit (6) through the installation mechanism (8) without stopping the machine. The next sleeve unit (6) is connected to the previous sleeve unit (6) through the connector (7). Then the positioning mechanism releases the clamp on the previous sleeve unit (6) and moves upward to clamp the next sleeve unit (6). After drilling the length of each sleeve unit (6), install the next sleeve unit (6) through the installation mechanism (8). After drilling three-quarters of the length of the drill rod (3), stop the machine to install the next drill rod (3). S4: After drilling to the set depth, simultaneously pull up the protective sleeve, drill bit (4) and drill rod (3). After pulling up the protective sleeve, remove each sleeve unit (6) from top to bottom. At the same time, the drill bit (4) continuously rotates and sprays grout into the borehole until the borehole opening is reached, thus completing the jet grouting operation.

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