A sequential linkage type directional limited domain rotary jetting device for slide belt cross-border reinforcement and a construction method thereof

Abstract

The application discloses a sequential linkage directional limited rotary jetting device for slide belt cross-boundary reinforcement and a construction method, and belongs to the technical field of landslide control and high-pressure jet grouting reinforcement. The device comprises coaxially nested outer drill rods, a slurry conveying pipe, a hollow control rod and a directional shaft, and a downhole sequential linkage rotary jetting execution head is arranged at the lower end; the execution head is integrated with a double-compression pack-off assembly, a wedge block type anti-torque locking assembly, a directional nozzle sleeve and a needle valve type opening and closing assembly. The hollow control rod is provided with three execution shoulders, which can sequentially drive the pack-off expansion, the circumferential locking and the jetting opening, form a forced time sequence interlocking, and reset in reverse order during the withdrawal. During the construction, the pack-off forms a limited jetting cavity section, directional jetting is performed after locking and positioning, and cross-boundary reinforcement short sections are formed. The application can improve the downhole pack-off reliability, jetting circumferential stability and directional accuracy, reduce the risk of slurry leakage and misjetting, and is suitable for directional short section reinforcement of slide belts and soft interlayers.

Description

Technical Field

[0001] This invention relates to the field of landslide control and high-pressure jet grouting reinforcement technology, and in particular to a sequential linkage directional confined jet grouting device and construction method for cross-boundary reinforcement of slip zones. Background Technology

[0002] Existing high-pressure jet grouting technology, when used for local reinforcement of slip zones, typically suffers from the following problems: First, the lack of a reliable downhole confinement structure before injection allows the grout to easily flow along the borehole wall, fissures, or loose areas, resulting in uneven formation of the target short section. Second, during injection, the nozzle is susceptible to circumferential displacement due to slurry backflow, uneven borehole wall friction, and lifting disturbances. Third, the lack of a stable rigid transmission relationship between the surface directional action and the actual downhole injection position leads to angular distortion. Fourth, the lack of a mandatory sequential relationship between sealing, locking, and injection initiation easily results in situations such as injection before sealing is completed, slurry cross-contamination after injection is stopped, or jamming. Therefore, a device and construction method are needed that can sequentially complete sealing, locking, directional control, and injection initiation downhole. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a sequential linkage directional confined jet grouting device and construction method for cross-boundary reinforcement of sliding zones, so as to solve the technical problems in the prior art such as unreliable isolation, unstable anti-torsion locking, inconsistency between ground orientation and actual downhole jetting orientation, and loss of control over the jetting opening and closing sequence.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a sequential linkage directional confined jet grouting device for cross-boundary reinforcement of sliding zones, comprising an outer drill pipe, a grout delivery pipe disposed within the outer drill pipe, a hollow control rod axially slidably disposed within the grout delivery pipe, a directional shaft rotatably disposed within the hollow control rod, and a downhole sequential linkage jet grouting actuator disposed at the lower ends of the outer drill pipe, the grout delivery pipe, the hollow control rod, and the directional shaft; an annular grout delivery channel is formed between the grout delivery pipe and the outer wall of the hollow control rod; The downhole sequential linkage rotary jetting actuator head is equipped with a rotatable nozzle sleeve, which is connected to the lower end of the directional shaft via a transmission connection; the side wall of the nozzle sleeve is equipped with a lateral nozzle. The lower end of the hollow control rod is provided with a first actuator shoulder, a second actuator shoulder, and a third actuator shoulder arranged sequentially and at intervals along the axial direction; The first actuator shoulder engages with the packer linkage sleeve to synchronously drive the upper compression packer assembly and the lower compression packer assembly to radially expand when the hollow control rod moves downward to the first stroke position; The second execution shoulder engages with the wedge-shaped drive sleeve to drive the wedge-type anti-torsion locking assembly to open radially and form a circumferential limit with the bore wall or the inner wall of the sleeve when the hollow control rod continues to move downward to the second stroke position after completing the first stroke. The third actuator shoulder cooperates with the top valve push rod to drive the needle valve opening and closing assembly to open when the hollow control rod continues to move downward to the third stroke position after completing the second stroke, so that the slurry enters the nozzle sleeve through the annular slurry delivery channel and is sprayed out from the side nozzle.

[0005] Preferably, the downhole sequential rotary jetting actuator includes an outer sleeve, an upper compression packer assembly disposed on the upper part of the outer sleeve, a lower compression packer assembly disposed on the lower part of the outer sleeve, a wedge-type anti-torsion locking assembly disposed between the upper compression packer assembly and the lower compression packer assembly, a nozzle sleeve rotatably disposed in the outer sleeve via an upper sealing support and a lower sealing support, a needle valve type opening and closing assembly disposed in the nozzle sleeve, and the lower end of the directional shaft that is drivenly connected to the nozzle sleeve.

[0006] Preferably, during a continuous downward movement of the hollow control rod, the downhole sequential linkage rotary jetting actuator sequentially completes the sealing, locking, and jetting initiation processes. When the hollow control rod retracts upward, the needle valve type opening and closing assembly, the wedge type anti-torsion locking assembly, the upper compression type sealing assembly, and the lower compression type sealing assembly are reset sequentially in the reverse order of opening.

[0007] Preferably, both the upper compression packer assembly and the lower compression packer assembly include a fixed conical ring, a movable pressure ring, and an elastic packer sleeve located between the fixed conical ring and the movable pressure ring; when the movable pressure ring is axially compressed, it slides along the conical surface of the fixed conical ring so that the elastic packer sleeve bulges radially outward and fits against the bore wall or the inner wall of the sleeve.

[0008] Preferably, the upper end of the sealing linkage sleeve contacts the first execution shoulder, and the lower end is respectively connected to the movable pressure rings of the upper compression sealing assembly and the lower compression sealing assembly to transmit force, so as to simultaneously press the two elastic sealing sleeves when the first execution shoulder moves down.

[0009] Preferably, the wedge-type anti-torsion locking assembly includes the wedge-shaped drive sleeve, three radial locking blocks evenly distributed circumferentially, and a return spring for retracting the radial locking blocks; the wedge-shaped drive sleeve moves axially downward under the drive of the second execution shoulder and pushes the three radial locking blocks outward through the wedge surface.

[0010] Preferably, the outer end of the radial locking block is provided with an anti-slip toothed layer or a hard wear-resistant layer.

[0011] Preferably, both the upper sealing support and the lower sealing support include a radial bearing, a sealing ring, and a labyrinth sealing groove to restrict slurry from entering the support fit gap while allowing the nozzle sleeve to rotate relative to the outer sleeve.

[0012] Preferably, the needle valve type opening and closing assembly includes a valve seat, a valve core, and a reset elastic element; the valve core disengages from the valve seat when the third actuator shoulder is driven by the top valve push rod, so that the annular slurry delivery channel is connected to the lateral nozzle; the valve core and the valve seat are fitted with a conical sealing fit.

[0013] Preferably, the valve core head is provided with a guide groove and an annular scraper edge. The annular scraper edge scrapes the slurry deposited at the valve seat inlet during the opening and closing process to reduce the risk of slurry blockage.

[0014] Preferably, the directional shaft and the nozzle sleeve are connected by a spline; the directional shaft and the hollow control rod are configured with a rotational isolation fit so that the directional shaft can rotate independently when the hollow control rod moves axially.

[0015] This invention discloses a construction method for reinforcing a sliding zone across a boundary using the aforementioned sequential linkage directional confined jet grouting device, comprising the following steps: S1. Drilling and lowering: After drilling a hole using the external drill pipe, the downhole sequential linkage rotary jetting actuator is lowered to the area to be reinforced. S2, Seal: Drive the hollow control rod downward to the first stroke position, so that the first execution shoulder synchronously drives the upper compression seal assembly and the lower compression seal assembly to expand through the seal linkage sleeve, forming a confined injection cavity section between the upper compression seal assembly and the lower compression seal assembly in the hole; S3. Locking: While maintaining the confined injection cavity segment formed in step S2, drive the hollow control rod to continue moving downward to the second stroke position, so that the second execution shoulder drives the wedge-shaped drive sleeve to move downward, thereby pushing the three radial locking blocks to open outward, so that the downhole sequential linkage rotary jet execution head forms a circumferential limit relative to the borehole wall or the inner wall of the casing. S4. Orientation: While maintaining the sealing and circumferential limiting state formed in steps S2 and S3, rotate the orientation shaft to turn the lateral nozzle to the designed spray position; S5. Spraying: After completing steps S2 to S4, drive the hollow control rod to continue moving downward to the third stroke position, so that the third execution shoulder drives the needle valve opening and closing assembly to open through the top valve push rod, and delivers high-pressure slurry into the annular slurry conveying channel, so that the slurry is sprayed out from the side nozzle to form a cross-boundary reinforcement short section. S6. Stop spraying and reset: After stopping the slurry delivery, drive the hollow control rod to retract upwards, first disengage the third actuator shoulder from the top valve push rod to close the needle valve opening and closing assembly, then disengage the second actuator shoulder from the wedge drive sleeve to retract the wedge anti-torsion locking assembly, and finally disengage the first actuator shoulder from the sealing linkage sleeve to release the sealing of the upper compression sealing assembly and the lower compression sealing assembly; S7. Relocation and Repetition: Move the downhole sequential linkage rotary jetting actuator to the next construction position and repeat steps S2 to S6.

[0016] Furthermore, in step S4, the lateral nozzle maintains a fixed orientation during the spraying process, or reciprocates within a range of 10° to 45° to form a fan-shaped spray area.

[0017] Furthermore, the cross-boundary reinforcement short section formed in step S5 includes, along the hole axis direction, an upper plate anchoring section located on the upper plate of the sliding belt, a sliding belt crossing section passing through the sliding belt body, and a lower plate anchoring section located on the lower plate of the sliding belt; wherein, the length of the upper plate anchoring section is 0.3m to 2.0m, the length of the sliding belt crossing section is 0.2m to 1.5m, and the length of the lower plate anchoring section is 0.3m to 2.0m.

[0018] Furthermore, the multiple cross-boundary reinforcement short segments are arranged in at least two staggered rows in a projection plane perpendicular to the slope direction; the center distance between adjacent cross-boundary reinforcement short segments in the same row is 0.6D to 1.2D, and the staggered offset between two adjacent rows is 0.3D to 0.8D, where D is the equivalent forming width of a single cross-boundary reinforcement short segment.

[0019] Furthermore, after the construction of a single cross-boundary reinforcement short segment is completed, the grouting volume per unit length q is used as the construction verification parameter, where q = V / L, V is the cumulative grouting volume of the cross-boundary reinforcement short segment, and L is the axial length of the cross-boundary reinforcement short segment; when q is lower than the preset lower limit, the cross-boundary reinforcement short segment is supplemented with grouting or the grouting time is extended.

[0020] Beneficial effects of this invention: 1. Forced timing interlock reduces the risk of accidental spraying and cross-contamination: This invention uses a three-stage execution shoulder arranged at intervals at the lower end of the hollow control rod to trigger the sealing expansion, anti-torsion locking, and needle valve opening actions in sequence through a continuous axial downward movement, forming a forced action sequence of sealing first, locking in the middle, and opening spraying last. When retracting, the valve is closed-unlocked-unsealed in reverse order, which structurally avoids problems such as spraying before sealing is completed and slurry flowing upward after spraying stops, significantly improving the timing reliability of downhole spraying operations and reducing the risk of accidental spraying and cross-contamination.

[0021] 2. Double-sealed confined grouting improves the concentration of the reinforced section: This invention uses two sets of upper and lower compression-type sealing components, which are simultaneously expanded and tightened to fit the hole wall before injection, forming a closed confined injection cavity. This can effectively prevent high-pressure grout from flowing along the hole wall, fissures or loose strata, so that the grouting formation range is concentrated and limited to the target reinforced area, ensuring that the forming boundary of the short section reinforcement of the sliding zone is clear, and improving the effective utilization rate of grouting materials and the targeted nature of reinforcement.

[0022] 3. Wedge-type circumferential locking enhances the stability of the injection process: The present invention sets a wedge-type anti-torsion locking component between the double packer components. Before injection, the radial locking block is pressed against the hole wall to form a circumferential limit, which can effectively offset the impact of high pressure back slurry, uneven friction of the hole wall and the circumferential deflection of the nozzle caused by operation disturbance, so that the downhole actuator remains circumferentially fixed during the injection process, avoids deviated injection and azimuth drift, and ensures the uniformity of directional injection.

[0023] 4. Rigid directional transmission ensures accurate azimuth control: This invention adopts a rigid transmission structure with a directional shaft and nozzle sleeve spline. The directional action and the axial reciprocating action of the hollow control rod are isolated from each other. The ground azimuth adjustment can be directly and without distortion transmitted to the downhole lateral nozzle, solving the problem of inconsistency between the ground setting and the actual injection azimuth in traditional structures. This significantly improves the azimuth control accuracy of directional reinforcement and is suitable for precise reinforcement needs such as directional cutting of sliding strips and local reinforcement.

[0024] 5. Needle valve type opening and closing anti-clogging, improving component service life and reliability: The present invention adopts a needle valve type opening and closing component with conical surface sealing. The injection is only opened after the sealing and locking are completed, and the opening and closing control is precise. The annular scraper edge set on the valve core head can scrape off the slurry deposited at the valve seat inlet during the opening and closing process. Combined with the conical surface sealing structure, it effectively reduces the risk of slurry blockage in high-pressure slurry environment, while improving the sealing durability and adapting to the working conditions of repeated opening and closing downhole. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the sequential linkage directional confined jet spray device of the present invention; Figure 2 This is a longitudinal cross-sectional view of the downhole sequential linkage rotary jet actuator of the present invention; Figure 3 This is a schematic diagram of the structure of the upper compression packer assembly and the lower compression packer assembly in the tightened state in this invention; Figure 4 This is a schematic diagram of the wedge-type anti-torsion locking assembly in the open-lock state of the present invention; Figure 5 This is a schematic diagram of the needle valve type opening and closing component in the present invention when it is in the open state; Figure 6This is a schematic diagram of the transmission connection between the directional shaft and the nozzle sleeve in this invention; Figure 7 This is a schematic diagram of the cross-boundary reinforcement short-segment deployment method in this invention; Explanation of reference numerals in the attached figures: 1—External drill pipe; 2—Grouting pipe; 21—Annular grouting channel; 3—Hollow control rod; 31—First execution shoulder; 32—Second execution shoulder; 33—Third execution shoulder; 4—Orientation shaft; 41—Surface azimuth drive head; 42—Azimuth reference mark; 5—Downhole sequential linkage rotary jetting execution head; 51—Outer sleeve; 52—Upper compression packer assembly; 521—Fixed cone ring; 522—Movable pressure ring; 523—Elastic packer sleeve; 53—Lower compression packer... 54—Wedge-type anti-torsion locking assembly; 541—Wedge-shaped drive sleeve; 542—Radial locking block; 543—Reset spring; 55—Nozzle sleeve; 55a—Upper sealing support; 55b—Lower sealing support; 551—Side nozzle; 56—Needle valve type opening and closing assembly; 561—Valve seat; 562—Valve core; 563—Reset elastic element; 564—Guide groove; 565—Annular scraper; 57—Sealing linkage sleeve; 58—Top valve push rod. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0027] Example 1: Overall Structure like Figure 1 and Figure 2 As shown, this embodiment provides a sequential linkage directional confined jet grouting device for cross-boundary reinforcement of sliding zones. The device includes an outer drill pipe 1, a grout delivery pipe 2 disposed within the outer drill pipe 1, a hollow control rod 3 axially slidably disposed within the grout delivery pipe 2, a directional shaft 4 rotatably inserted within the hollow control rod 3, and a downhole sequential linkage jet grouting actuator 5 disposed at the lower ends of the outer drill pipe 1, the grout delivery pipe 2, the hollow control rod 3, and the directional shaft 4.

[0028] The grout delivery pipe 2 is fixedly installed inside the outer drill pipe 1, forming an annular grout delivery channel 21 between the grout delivery pipe 2 and the outer wall of the hollow control rod 3. The annular grout delivery channel 21 is used to transport high-pressure grout from the surface to the downhole sequential rotary jetting actuator 5. The directional shaft 4 passes through the hollow control rod 3 and forms a rotational isolation fit with the hollow control rod 3, ensuring that the directional shaft 4 does not affect the independent rotation of the hollow control rod 3 when the hollow control rod 3 performs axial downward and upward movements.

[0029] The downhole sequential linkage rotary jetting actuator 5 includes an outer sleeve 51, an upper compression packer assembly 52 disposed on the upper part of the outer sleeve 51, a lower compression packer assembly 53 disposed on the lower part of the outer sleeve 51, a wedge-type anti-torsion locking assembly 54 disposed between the upper compression packer assembly 52 and the lower compression packer assembly 53, a nozzle sleeve 55 rotatably disposed in the outer sleeve 51 via an upper sealing support 55a and a lower sealing support 55b, a needle valve type opening and closing assembly 56 disposed in the nozzle sleeve 55, a packer linkage sleeve 57 cooperating with the first actuator shoulder 31, and a top valve push rod 58 cooperating with the third actuator shoulder 33. A lateral nozzle 551 is provided on the side wall of the nozzle sleeve 55. The lower end of the directional shaft 4 is connected to the nozzle sleeve 55 for driving the nozzle sleeve 55 and the lateral nozzle 551 to rotate around the axis.

[0030] The lower end of the hollow control rod 3 is provided with a first actuating shoulder 31, a second actuating shoulder 32, and a third actuating shoulder 33 arranged sequentially along the axial direction. The first actuating shoulder 31 is used to drive the upper compression packer assembly 52 and the lower compression packer assembly 53 to tighten; the second actuating shoulder 32 is used to continue driving the wedge-type anti-torsion locking assembly 54 to open after the first actuating shoulder 31 completes the packing action; the third actuating shoulder 33 is used to continue driving the needle valve type opening and closing assembly 56 to open after the second actuating shoulder 32 completes the locking action. Thus, a single continuous axial downward movement of the hollow control rod 3 can cause the downhole sequential linkage rotary jet actuator 5 to complete the packing, locking, and jetting actions in sequence; during the upward and retraction process of the hollow control rod 3, the valve closing, unlocking, and unsealing actions are completed in sequence.

[0031] Example 2: Upper compression packer assembly and lower compression packer assembly like Figure 2 and Figure 3 As shown, the upper compression packer assembly 52 and the lower compression packer assembly 53 have the same structure, both including a fixed cone ring 521, a movable pressure ring 522, and an elastic packer sleeve 523 located between the fixed cone ring 521 and the movable pressure ring 522.

[0032] A fixed conical ring 521 is fixedly mounted on an outer sleeve 51, and a movable pressure ring 522 can move axially relative to the fixed conical ring 521. An elastic sealing sleeve 523 is fitted around the outer circumference of the fixed conical ring 521, with one end positioned and connected to the fixed conical ring 521, and the other end engaging with the movable pressure ring 522. When the movable pressure ring 522 moves axially toward the fixed conical ring 521, it slides relative to the conical surface of the fixed conical ring 521, thereby applying axial compression to the elastic sealing sleeve 523. Because the outer surface of the fixed conical ring 521 is an outwardly expanding conical surface, the elastic sealing sleeve 523 bulges radially outward after being compressed and presses against the bore wall or the inner wall of the sleeve to form a seal.

[0033] In this embodiment, the elastic packer 523 can be made of wear-resistant rubber, polyurethane elastomer, or other elastic sealing materials suitable for downhole high-pressure environments. The outer circumferential surface of the elastic packer 523 can be provided with annular anti-slip textures to improve the stability of the fit with the borehole wall or the inner wall of the casing.

[0034] The sealing linkage sleeve 57 is disposed inside the outer sleeve 51 and can slide axially relative to the outer sleeve 51. The upper end of the sealing linkage sleeve 57 contacts the first actuating shoulder 31, and the lower part of the sealing linkage sleeve 57 forms upper and lower force transmission parts, which are respectively connected to the movable pressure rings 522 of the upper compression sealing assembly 52 and the lower compression sealing assembly 53 for force transmission. When the hollow control rod 3 moves down to the first stroke position, the first actuating shoulder 31 presses the sealing linkage sleeve 57 down, and the sealing linkage sleeve 57 simultaneously pushes the movable pressure rings 522 of the upper compression sealing assembly 52 and the lower compression sealing assembly 53 to move axially, so that the upper and lower elastic sealing sleeves 523 simultaneously expand and fit against the bore wall or the inner wall of the sleeve.

[0035] In this embodiment, the axial length of the elastic packer sleeve 523 of both the upper compression packer assembly 52 and the lower compression packer assembly 53 can be set to 100mm to 150mm; the axial displacement corresponding to the first stroke can be set to 22mm to 35mm. The net distance between the upper compression packer assembly 52 and the lower compression packer assembly 53 can be set to 180mm to 420mm to form a confined injection cavity between them.

[0036] Example 3: Wedge-type anti-torsion locking assembly like Figure 2 and Figure 4 As shown, the wedge-type anti-torsion locking assembly 54 is disposed between the upper compression sealing assembly 52 and the lower compression sealing assembly 53, and includes a wedge-shaped drive sleeve 541, three radial locking blocks 542 evenly distributed circumferentially, and a return spring 543 for retracting the radial locking blocks 542.

[0037] A wedge-shaped drive sleeve 541 is fitted inside the outer sleeve 51 and can move axially relative to the outer sleeve 51. The outer periphery of the wedge-shaped drive sleeve 541 forms an expanding wedge surface, and three radial locking blocks 542 are respectively disposed in radial guide grooves corresponding to the wedge-shaped drive sleeve 541. The inner side of each radial locking block 542 has an inclined surface that mates with the expanding wedge surface of the wedge-shaped drive sleeve 541. A return spring 543 is disposed between the radial locking blocks 542 and the outer sleeve 51, used to pull or push the radial locking blocks 542 back to their initial position when the wedge-shaped drive sleeve 541 returns to its original position.

[0038] When the hollow control rod 3 continues to move down to the second stroke position after completing the first stroke, the second actuator shoulder 32 contacts the wedge-shaped drive sleeve 541 and pushes the wedge-shaped drive sleeve 541 to continue moving down. Since there is a wedge surface fit between the wedge drive sleeve 541 and the radial locking block 542, the three radial locking blocks 542 are pushed outward radially during the downward movement of the wedge drive sleeve 541, so that their outer ends press against the borehole wall or the inner wall of the casing, thereby forming a circumferential limit between the downhole sequential linkage rotary jet actuator 5 and the borehole wall or the inner wall of the casing.

[0039] In this embodiment, the three radial locking blocks 542 are evenly distributed at 120° along the circumference. The wedge angle of the wedge-shaped drive sleeve 541 can be set to 8° to 15°. The axial displacement corresponding to the second stroke can be set to 10mm to 18mm. The outer end of the radial locking block 542 can be provided with an anti-slip toothed layer or a hard wear-resistant layer to improve the anti-slip ability during locking and reduce wear.

[0040] Example 4: Nozzle sleeve, directional shaft and sealing support structure like Figure 2 and Figure 6 As shown, the nozzle sleeve 55 is located in the middle section inside the outer sleeve 51, and forms a rotatable support fit with the outer sleeve 51 through the upper sealing support member 55a and the lower sealing support member 55b. Both the upper sealing support member 55a and the lower sealing support member 55b include radial bearings, sealing rings, and labyrinth sealing grooves, so as to restrict the slurry from entering the support fit gap while allowing the nozzle sleeve 55 to rotate relative to the outer sleeve 51.

[0041] The sidewall of the nozzle sleeve 55 is provided with a lateral nozzle 551. The lateral nozzle 551 can be configured as a single nozzle, or it can be configured as multiple spray holes arranged in the same circumferential direction without changing the basic concept of the present invention. To avoid unnecessary expansion, this embodiment adopts a single lateral nozzle 551 structure.

[0042] The lower end of the directional shaft 4 is splined to the nozzle sleeve 55. The upper end of the directional shaft 4 extends to the ground and is equipped with a ground azimuth drive head 41 and an azimuth reference mark 42. When the ground construction personnel rotate the directional shaft 4, the directional shaft 4 drives the nozzle sleeve 55 to rotate synchronously through the spline drive, thereby turning the lateral nozzle 551 to the corresponding designed injection azimuth. Since the directional shaft 4 and the nozzle sleeve 55 are rigidly connected by transmission, the hollow control rod 3 only undertakes axial execution and not circumferential orientation, thus improving the consistency between the ground-set azimuth and the actual injection azimuth downhole.

[0043] In this embodiment, the directional shaft 4 and the hollow control rod 3 are connected by a rotational isolation fit. The rotational isolation fit can be a combination of an axial limiting component and a low-friction rotating fit component, allowing the hollow control rod 3 to move axially back and forth relative to the directional shaft 4 without causing the directional shaft 4 to rotate synchronously.

[0044] Example 5: Needle valve type opening and closing assembly and flow guiding and anti-clogging structure like Figure 2 and Figure 5 As shown, the needle valve type opening and closing assembly 56 is disposed inside the nozzle sleeve 55, including a valve seat 561, a valve core 562, and a reset elastic element 563. The valve seat 561 is fixedly disposed in the flow channel inside the nozzle sleeve 55, and the valve core 562 is axially movable relative to the valve seat 561. The valve core 562 and the valve seat 561 are fitted with a conical surface seal. The reset elastic element 563 is used to push the valve core 562 back to the closed position after the external force is released.

[0045] The top valve push rod 58 is positioned between the lower end of the hollow control rod 3 and the needle valve type opening and closing assembly 56. Its upper end engages with the third actuator shoulder 33, and its lower end contacts the valve core 562. When the hollow control rod 3 completes its second stroke and continues to move downward to the third stroke position, the third actuator shoulder 33 pushes the top valve push rod 58 downward. The top valve push rod 58 pushes the valve core 562 against the elastic force of the reset elastic element 563, causing the valve core 562 to disengage from the valve seat 561, thereby opening the injection channel. At this time, the high-pressure slurry in the annular slurry delivery channel 21 enters the nozzle sleeve 55 and is ejected through the side nozzle 551.

[0046] The head of the valve core 562 is provided with a guide groove 564 and an annular scraper 565. The guide groove 564 is used to guide the slurry smoothly into the internal flow channel of the nozzle sleeve 55 when the valve core 562 is opened; the annular scraper 565 is used to scrape the slurry deposited at the inlet of the valve seat 561 during the opening or closing of the valve core 562, so as to reduce the risk of blockage caused by slurry deposition.

[0047] In this embodiment, the axial displacement corresponding to the third stroke can be set to 5mm to 10mm. The valve core 562 and valve seat 561 can be made of wear-resistant metal material, and their sealing cone surface can be hardened to improve durability and sealing stability during repeated opening and closing processes.

[0048] Example 6: Dimensional and Structural Parameters In this embodiment, a feasible size scheme for the entire device is as follows: The outer diameter of the outer drill pipe 1 is 89mm, and the inner diameter is 62mm; The outer diameter of the grout delivery pipe 2 is 42mm, and the inner diameter is 28mm; The hollow control rod 3 has an outer diameter of 20mm and an inner diameter of 10mm; The outer diameter of the orientation shaft 4 is 8mm; The equivalent flow area of ​​the annular slurry conveying channel 21 is 300 mm² to 500 mm². The nozzle sleeve 55 has an outer diameter of 44mm; The orifice diameter of the lateral nozzle 551 is 2.0mm to 3.5mm; The axial length of the elastic packer sleeve 523 of both the upper compression packer assembly 52 and the lower compression packer assembly 53 is 100mm to 150mm. The net distance between the upper compression packer assembly 52 and the lower compression packer assembly 53 is 180mm to 420mm; The wedge angle of the wedge-shaped drive sleeve 541 is 8° to 15°; The first stroke is 22mm to 35mm; The second stroke is 10mm to 18mm; The third stroke is 5mm to 10mm.

[0049] The dimensions and parameters described above can meet the structural layout and operational requirements under typical localized directional jet reinforcement conditions for sliding belts. For engineering conditions with different orifice diameters, sliding belt thicknesses, or construction depths, those skilled in the art can make proportional adjustments or conventional engineering adjustments based on the above ranges.

[0050] Example 7: Construction Method When using this invention for cross-boundary reinforcement of the sliding belt, such as Figures 1 to 7 As shown, the construction can be carried out according to the following steps: (1) Drilling and lowering: After drilling using the external drill pipe 1, the downhole sequential linkage jet grouting actuator 5 is lowered to the section to be reinforced. The section to be reinforced can be determined based on the exploration data, borehole data, or construction design.

[0051] (2) Separation: Drive the hollow control rod 3 to move downward to the first stroke position, so that the first execution shoulder 31 drives the upper compression sealing assembly 52 and the lower compression sealing assembly 53 to expand and tighten through the sealing linkage sleeve 57, thereby forming a confined injection cavity section between the upper compression sealing assembly 52 and the lower compression sealing assembly 53 in the hole.

[0052] (3) Locking: Drive the hollow control rod 3 to continue moving downward to the second stroke position, so that the second execution shoulder 32 drives the wedge drive sleeve 541 to move downward. The wedge drive sleeve 541 pushes the three radial locking blocks 542 outward through the wedge surface, so that the downhole sequential linkage rotary jet execution head 5 forms a circumferential limit relative to the borehole wall or the inner wall of the casing.

[0053] (4) Orientation: Rotate the orientation shaft 4 to rotate the lateral nozzle 551 to the designed spraying position. The designed spraying position can be determined according to the extension direction of the sliding belt, the designed cutting direction, the normal direction of the slope, or other construction design directions.

[0054] (5) Spraying: Drive the hollow control rod 3 to continue moving downward to the third stroke position, so that the third execution shoulder 33 drives the needle valve opening and closing assembly 56 to open through the top valve push rod 58, and delivers high pressure slurry into the annular slurry channel 21, so that the slurry passes through the nozzle sleeve 55 and is sprayed out from the side nozzle 551 to form a cross-boundary reinforcement short section.

[0055] (6) Stop spraying and reset: After stopping the slurry delivery, drive the hollow control rod 3 to retract upwards. When the hollow control rod 3 retracts initially, the third actuator shoulder 33 disengages from the top valve push rod 58, causing the needle valve type opening and closing assembly 56 to close under the action of the reset elastic element 563; when the hollow control rod 3 continues to move upwards, the second actuator shoulder 32 disengages from the wedge-shaped drive sleeve 541, causing the wedge-type anti-torsion locking assembly 54 to retract under the action of the reset spring 543; when the hollow control rod 3 continues to move upwards, the first actuator shoulder 31 disengages from the sealing linkage sleeve 57, causing the upper compression sealing assembly 52 and the lower compression sealing assembly 53 to release the seal.

[0056] (7) Relocation and repetition: Move the downhole sequential linkage jet jet actuator 5 to the next construction position and repeat the above steps until the construction of all designed reinforcement sections is completed.

[0057] In the above steps, the continuous downward movement of the hollow control lever 3 only triggers the injection after the sealing and locking are completed; when the injection stops and retracts, the needle valve opening and closing assembly 56 is closed first, then the anti-torsion locking is released, and finally the sealing is released, thus forming a reverse timing reset corresponding to the downward movement.

[0058] Example 8: Injection Parameters and Injection Method In this embodiment, the injection pressure of the high-pressure grout can be set to 20MPa to 35MPa, and the grout flow rate can be set to 45L / min to 90L / min. The axial length of the short section for single-stage cross-boundary reinforcement can be set to 0.4m to 2.5m.

[0059] The side nozzle 551 can operate in two modes during the spraying process: The first method is fixed-position spraying, that is, keeping the lateral nozzle 551 in a preset fixed position during the spraying process; The second method is small-angle oscillating spray, that is, in the state of sealing and locking, the directional shaft 4 is driven to make the lateral nozzle 551 reciprocate on both sides of the fixed reference position. The oscillation angle can be set to 10° to 45° to form a fan-shaped spray area.

[0060] When using the small-angle oscillating spray method, the circumferential oscillation of the side nozzle 551 and the axial movement of the hollow control rod 3 are performed independently, and the needle valve type opening and closing assembly 56 is only in the open state at the third stroke position.

[0061] Example 9: Cross-boundary reinforcement of short sections and planar layout In this embodiment, the cross-boundary reinforcement short section formed in step (5) includes, along the hole axis direction, an upper plate anchoring section located on the upper plate of the sliding belt, a cross-sliding belt section passing through the sliding belt body, and a lower plate anchoring section located on the lower plate of the sliding belt.

[0062] The length of the upper anchorage section can be set to 0.3m to 2.0m, the length of the section spanning the sliding band can be set to 0.2m to 1.5m, and the length of the lower anchorage section can be set to 0.3m to 2.0m. The specific length can be determined according to the thickness of the sliding band, the continuity of the weak layer, and the design reinforcement requirements.

[0063] Multiple cross-boundary reinforcement short sections can be arranged in at least two staggered rows within a projection plane perpendicular to the slope. The center-to-center distance between adjacent cross-boundary reinforcement short sections in the same row can be set to 0.6D to 1.2D, and the staggered offset between two adjacent rows can be set to 0.3D to 0.8D, where D is the equivalent forming width of a single cross-boundary reinforcement short section. The equivalent forming width D can be determined based on test sections, sampling holes, core sampling results, side hole detection results, or other conventional testing results.

[0064] In a specific working condition, the length of the upper anchorage section can be set to 0.5m to 1.2m, the length of the sliding band section can be set to 0.3m to 0.9m, and the length of the lower anchorage section can be set to 0.5m to 1.2m; the center distance between adjacent rows can be set to 0.7D to 1.0D, and the offset between two adjacent rows can be set to 0.4D to 0.6D.

[0065] Example 10: Construction Verification After the completion of a short section of cross-boundary reinforcement construction, the construction can be checked according to the grouting volume q per unit length, where: q = V / L In the formula, V is the cumulative grouting volume of the cross-boundary reinforcement short section, and L is the axial length of the cross-boundary reinforcement short section.

[0066] When q is lower than the preset lower limit, additional spraying or extended spraying time can be performed on the short section of the cross-boundary reinforcement; when q is within the design allowable range, construction can proceed to the next construction location. The preset range of grouting volume q per unit length can be determined based on test sections, design requirements, or on-site calibration results.

[0067] Example 11: Comparison of construction conditions Under the same hole-forming conditions, the same slurry mix ratio, and the same injection pressure, the following two sets of construction conditions can be compared.

[0068] In the comparative test, using a conventional directional spray head that does not have a three-stage sequential linkage structure, spraying was started before the seal was fully formed, resulting in issues such as upper grout cross-flow, initial spray deviation, and nozzle position fluctuation during spraying.

[0069] When using the device of this invention for construction, the first execution shoulder 31 drives the upper compression sealing assembly 52 and the lower compression sealing assembly 53 to form a confined spraying cavity. Then, the second execution shoulder 32 drives the wedge-type anti-torsion locking assembly 54 to complete circumferential limiting. Finally, the third execution shoulder 33 drives the needle valve type opening and closing assembly 56 to start spraying. Under this condition, no premature slurry discharge occurs at the spraying front end, and no obvious upward slurry return is observed after spraying stops. The forming boundary of the short spraying section is relatively concentrated, and the actual orientation of the lateral nozzle 551 remains stable during the spraying process.

[0070] Example 12: Other Implementation Methods Without altering the basic concept of this invention, the cone angle of the upper compression sealing assembly 52 and the lower compression sealing assembly 53, the material and dimensions of the elastic sealing sleeve 523, the surface wear-resistant layer form of the radial locking block 542 in the wedge-type anti-torsion locking assembly 54, the number and diameter of the nozzles in the nozzle sleeve 55, the type of the reset elastic element 563 of the needle valve opening and closing assembly 56, and the specific structural form of the ground orientation drive head 41 can all be adjusted according to the actual construction conditions.

[0071] For different apertures and different formation conditions, those skilled in the art can make adaptive designs based on the structural relationships, action sequences and parameter ranges disclosed in this specification without affecting the implementation of the present invention.

[0072] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts, characterized in that, The system includes an outer drill pipe (1), a grout delivery pipe (2) installed inside the outer drill pipe (1), a hollow control rod (3) slidably installed inside the grout delivery pipe (2), a directional shaft (4) rotatably installed inside the hollow control rod (3), and a downhole sequential linkage rotary jetting actuator (5) installed at the lower ends of the outer drill pipe (1), the grout delivery pipe (2), the hollow control rod (3), and the directional shaft (4); an annular grout delivery channel (21) is formed between the grout delivery pipe (2) and the outer wall of the hollow control rod (3); The downhole sequential linkage rotary jet actuator (5) is equipped with a rotatable nozzle sleeve (55), which is connected to the lower end of the directional shaft (4) via a drive; the side wall of the nozzle sleeve (55) is equipped with a lateral nozzle (551). The lower end of the hollow control rod (3) is provided with a first execution shoulder (31), a second execution shoulder (32) and a third execution shoulder (33) arranged sequentially along the axial direction. The first execution shoulder (31) cooperates with the sealing linkage sleeve (57) to synchronously drive the upper compression sealing assembly (52) and the lower compression sealing assembly (53) to radially expand when the hollow control rod (3) moves downward to the first stroke position; The second execution shoulder (32) cooperates with the wedge-shaped drive sleeve (541) to drive the wedge-type anti-torsion locking assembly (54) to open radially and form a circumferential limit with the hole wall or the inner wall of the sleeve when the hollow control rod (3) continues to move downward to the second stroke position after completing the first stroke; The third execution shoulder (33) cooperates with the top valve push rod (58) to drive the needle valve opening and closing assembly (56) to open when the hollow control rod (3) continues to move downward to the third stroke position after completing the second stroke, so that the slurry enters the nozzle sleeve (55) through the annular slurry conveying channel (21) and is sprayed out from the side nozzle (551).

2. The sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 1, characterized in that, The downhole sequential linkage rotary jet actuator (5) includes an outer sleeve (51), an upper compression packer assembly (52) disposed on the upper part of the outer sleeve (51), a lower compression packer assembly (53) disposed on the lower part of the outer sleeve (51), a wedge-type anti-torsion locking assembly (54) disposed between the upper compression packer assembly (52) and the lower compression packer assembly (53), a nozzle sleeve (55) rotatably disposed in the outer sleeve (51) via an upper sealing support (55a) and a lower sealing support (55b), a needle valve type opening and closing assembly (56) disposed in the nozzle sleeve (55), and the lower end of the directional shaft (4) which is drivenly connected to the nozzle sleeve (55).

3. The sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, During a continuous downward movement, the hollow control rod (3) causes the downhole sequential linkage rotary jet actuator (5) to sequentially complete the sealing, locking, and jetting. When the hollow control rod (3) retracts upward, the needle valve type opening and closing assembly (56), the wedge type anti-torsion locking assembly (54), the upper compression type sealing assembly (52), and the lower compression type sealing assembly (53) are reset sequentially in the reverse order of opening.

4. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, Both the upper compression packer assembly (52) and the lower compression packer assembly (53) include a fixed conical ring (521), a movable pressure ring (522), and an elastic packer sleeve (523) located between the fixed conical ring (521) and the movable pressure ring (522). When the movable pressure ring (522) is axially compressed, it slides along the conical surface of the fixed conical ring (521) so that the elastic packer sleeve (523) bulges outward in the radial direction and fits against the bore wall or the inner wall of the sleeve.

5. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, The upper end of the sealing linkage sleeve (57) contacts the first execution shoulder (31), and the lower end is connected to the movable pressure ring (522) of the upper compression sealing assembly (52) and the lower compression sealing assembly (53) respectively to transmit force, so as to simultaneously press the two elastic sealing sleeves (523) when the first execution shoulder (31) moves down.

6. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, The wedge-type anti-torsion locking assembly (54) includes the wedge-shaped drive sleeve (541), three radial locking blocks (542) evenly distributed circumferentially, and a return spring (543) for retracting the radial locking blocks (542); the wedge-shaped drive sleeve (541) moves axially downward under the drive of the second execution shoulder (32) and pushes the three radial locking blocks (542) outward through the wedge surface.

7. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 6, characterized in that, The outer end of the radial locking block (542) is provided with an anti-slip toothed layer or a hard wear-resistant layer.

8. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, Both the upper sealing support (55a) and the lower sealing support (55b) include radial bearings, sealing rings, and labyrinth sealing grooves to restrict slurry from entering the support fit gap while allowing the nozzle sleeve (55) to rotate relative to the outer sleeve (51).

9. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, The needle valve type opening and closing assembly (56) includes a valve seat (561), a valve core (562), and a reset elastic element (563); the valve core (562) disengages from the valve seat (561) when the third actuator shoulder (33) is driven by the top valve push rod (58), so that the annular slurry channel (21) is connected to the side nozzle (551); the valve core (562) and the valve seat (561) are fitted with a conical sealing fit.

10. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 9, characterized in that, The valve core (562) head is provided with a guide groove (564) and an annular scraper (565). The annular scraper (565) scrapes the slurry deposited at the inlet of the valve seat (561) during the opening and closing process to reduce the risk of slurry blockage.

11. A sequential linkage directional confined jet spraying device for cross-boundary reinforcement of sliding belts according to claim 2, characterized in that, The directional shaft (4) and the nozzle sleeve (55) are connected by a spline; the directional shaft (4) and the hollow control rod (3) are provided with a rotational isolation fit so that the directional shaft (4) can rotate independently when the hollow control rod (3) moves axially.

12. A construction method for reinforcing a sliding zone across a boundary using a sequentially linked directional confined jet grouting device as described in any one of claims 1 to 11, characterized in that, Includes the following steps: S1. Drilling and lowering: After drilling using the external drill pipe (1), the downhole sequential linkage rotary jetting actuator (5) is lowered to the area to be reinforced. S2, Seal: Drive the hollow control rod (3) to move downward to the first stroke position, so that the first execution shoulder (31) drives the upper compression seal assembly (52) and the lower compression seal assembly (53) to expand through the seal linkage sleeve (57), forming a confined injection cavity section between the upper compression seal assembly (52) and the lower compression seal assembly (53) in the hole; S3, Locking: While maintaining the confined injection cavity formed in step S2, drive the hollow control rod (3) to continue moving downward to the second stroke position, so that the second execution shoulder (32) drives the wedge drive sleeve (541) to move downward, thereby pushing the three radial locking blocks (542) to open outward, so that the downhole sequential linkage rotary jet execution head (5) forms a circumferential limit relative to the borehole wall or the inner wall of the casing; S4, Orientation: While maintaining the sealing and circumferential limiting state formed in steps S2 and S3, rotate the orientation shaft (4) to rotate the lateral nozzle (551) to the designed spray position; S5, Spraying: After completing steps S2 to S4, drive the hollow control rod (3) to continue moving downward to the third stroke position, so that the third execution shoulder (33) drives the needle valve opening and closing assembly (56) to open through the top valve push rod (58), and delivers high pressure slurry into the annular slurry channel (21), so that the slurry is sprayed out from the side nozzle (551) to form a cross-boundary reinforcement short section; S6. Stop spraying and reset: After stopping the slurry delivery, drive the hollow control rod (3) to retract upwards, first disengage the third execution shoulder (33) from the top valve push rod (58) to close the needle valve opening and closing assembly (56), then disengage the second execution shoulder (32) from the wedge drive sleeve (541) to retract the wedge anti-torsion locking assembly (54), and finally disengage the first execution shoulder (31) from the sealing linkage sleeve (57) to release the sealing of the upper compression sealing assembly (52) and the lower compression sealing assembly (53); S7. Relocation and Repetition: Move the downhole sequential linkage rotary jetting actuator (5) to the next construction position and repeat steps S2 to S6.

13. The construction method according to claim 12, characterized in that, In step S4, the lateral nozzle (551) maintains a fixed orientation during the spraying process, or swings back and forth within a range of 10° to 45° to form a fan-shaped spray area.

14. The construction method according to claim 12, characterized in that, The cross-boundary reinforcement short section formed in step S5 includes, along the hole axis direction, an upper plate anchoring section located on the upper plate of the sliding belt, a sliding belt crossing section passing through the sliding belt body, and a lower plate anchoring section located on the lower plate of the sliding belt; wherein, the length of the upper plate anchoring section is 0.3m to 2.0m, the length of the sliding belt crossing section is 0.2m to 1.5m, and the length of the lower plate anchoring section is 0.3m to 2.0m.

15. The construction method according to claim 12, characterized in that, The multiple cross-boundary reinforcement short segments are arranged in at least two rows in a staggered manner in a projection plane perpendicular to the slope direction; the center distance between adjacent cross-boundary reinforcement short segments in the same row is 0.6D to 1.2D, and the staggered offset between two adjacent rows is 0.3D to 0.8D, where D is the equivalent forming width of a single cross-boundary reinforcement short segment.

16. The construction method according to claim 12, characterized in that, After the construction of a single cross-boundary reinforcement short section is completed, the grouting volume per unit length q is used as the construction verification parameter, where q = V / L, V is the cumulative grouting volume of the cross-boundary reinforcement short section, and L is the axial length of the cross-boundary reinforcement short section; when q is lower than the preset lower limit, the cross-boundary reinforcement short section is supplemented with grouting or the grouting time is extended.

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