Directional core sampling apparatus and method for layered soft rock

Abstract

This invention relates to the field of geotechnical engineering exploration and geological sampling technology, and discloses a directional core sampling device and method for layered soft rock. The device includes a drilling system, an angle adjustment and support system, and a laser positioning system. The angle adjustment and support system uses a combination of modular scaffolding steel pipes and quick-connect fasteners. By adjusting the height difference of independent supports, the spatial angle of the rigid track can be flexibly and stably adjusted. The laser positioning system uses a beam of light parallel to the track to visually calibrate and verify the drilling trajectory. The method includes on-site assembly, preliminary horizontal drilling to confirm lithology and occurrence, calculation and adjustment of the track to the target angle, laser verification, directional drilling using water or gas media, and continuous parallel sampling by translating along the guide steel pipe. This invention solves the problem of the difficulty in accurately controlling the angle between the drilling direction and the bedding plane in traditional methods, and achieves high-precision, high-fidelity, and high-efficiency directional sampling of layered soft rock.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering investigation and geological sampling technology, specifically to a directional core sampling device and method for layered soft rock. Background Technology

[0002] In geotechnical engineering, geological hazard assessment, and geological research, obtaining core samples that retain information about the original bedding structure is crucial. The mechanical properties of layered soft rocks (such as shale, mudstone, and slate) exhibit significant anisotropy; their strength and deformation characteristics are closely related to the strike and dip angle of the bedding planes. While traditional core drilling methods (such as those using vertical-shaft or fully hydraulic drilling rigs) can obtain core samples, they struggle to precisely control the angle between the drilling direction and the bedding planes, failing to meet the directional sampling requirements for core samples with specific attitudes (such as bedding-parallel, cross-bedding, and perpendicular bedding).

[0003] In the existing technology, there are some devices that attempt to solve the problem of on-site directional sampling, such as those using complex orientation adjustment mechanisms and fixed bases. However, these devices usually have the following drawbacks: the equipment is bulky, inconvenient to transport and install, and has poor adaptability, especially in uneven slopes or tunnels; the angle adjustment mechanism is complex, costly, and lacks adjustment accuracy and stability; and there is a lack of rapid and intuitive angle positioning and verification methods, which leads to deviations in the sampling angle. Summary of the Invention

[0004] This invention provides a directional core sampling device and method for layered soft rock to solve the above-mentioned problems.

[0005] In a first aspect, the present invention provides a directional core sampling device for layered soft rock, comprising:

[0006] A drilling rig system includes a drilling rig, a rigid rail, and a drilling rig mounting bracket. The drilling rig is mounted on the rigid rail via the drilling rig mounting bracket and is capable of linear feed and retraction along the rigid rail. Angle adjustment and support system, consisting of multiple scaffolding steel pipes connected by quick-connect couplers, includes a bottom support frame and at least two parallel supports with independently adjustable heights. The rigid rails overlap and are fixed to the top crossbars of the supports. The laser positioning system includes two laser emitters, which are fixed to the side of the rigid track by clamps. The laser beams emitted by the laser emitters are parallel to the extension direction of the rigid track.

[0007] The rigid rail serves as the guiding reference for the drilling rig's operation. The drilling rig is securely mounted on this rigid rail via a drilling rig mounting bracket, enabling the rig to perform precise linear feed or retraction along the length of the rigid rail, thus ensuring the straightness of the drilling trajectory. The bracket body can be a rigid metal frame, with one or more sliders or rollers integrated at its bottom that match the cross-sectional shape of the rigid rail. Through these sliders or rollers, the entire bracket can engage or straddle the rigid rail with low resistance, achieving smooth linear sliding.

[0008] The angle adjustment and support system provides stable support for the entire structure and enables angle adjustment. This system consists of multiple standard-sized scaffolding steel pipes interconnected by quick-connect couplers, exhibiting a high degree of modularity and reconfigurability. Its main body includes a bottom support frame constructed of steel pipes, providing a stable foundation for the entire structure. Above this bottom support frame, at least two parallel vertical supports are installed, each with an independently adjustable height. The two ends of the rigid track are directly overlapped and fixed to the horizontal bars at the top of these two supports. By adjusting the height of the two supports individually, the spatial inclination angle of the rigid track can be changed in the vertical plane.

[0009] The quick-connect coupler's main body is a high-strength cast iron or forged steel body with an internal cross-shaped slot for accommodating two perpendicularly intersecting steel pipes. The slot dimensions match standard scaffolding steel pipes. The quick-connect coupler also includes a locking mechanism, primarily consisting of a bolt penetrating the coupler body and a pair of wedge-shaped slips that mate with the bolt's ends. During operation, after placing the two steel pipes into the corresponding slots, no additional tools are needed; simply rotate the wing nut at the bolt end by hand or quickly pull the handle. Rotating the bolt drives the two wedge-shaped slips to move relative to each other along the inclined plane, thus firmly securing them against the outer wall of the steel pipes from the inside. This is a standard structure and will not be elaborated further here.

[0010] The laser positioning system is used for visual calibration and verification of a predetermined drilling trajectory. The system consists of two high-precision laser emitters, which are respectively fixed to two sides of a rigid track using clamps. During installation, precise calibration is required to ensure that the laser beams emitted by both emitters are strictly parallel to the extension direction of the rigid track. Thus, the line connecting the two laser beams projected onto the rock wall visually represents the future drilling axis of the drill bit, providing a visible reference for angle adjustments.

[0011] This device enables flexible and stable adjustment of the drilling rig angle through a modular support system, and achieves high-precision visual control of the drilling direction with the help of a laser positioning system, laying the foundation for obtaining directional rock cores with specific occurrences.

[0012] In one optional embodiment, the clamp of the laser positioning system is a detachable snap-fit ​​structure that adapts to the cross-sectional dimensions of the rigid track, for quickly installing and fixing the laser emitter.

[0013] In one alternative embodiment, the drilling system further includes two track stabilizing rods, which are arranged horizontally and connected to the two ends of the rigid track, respectively.

[0014] In one optional embodiment, the drilling rig fixed bracket is provided with a drilling rig feed handle. The handle is a cylindrical grip structure that is mechanically linked to the drilling rig spindle and is used to manually control the drilling rig to feed or retract along the rigid track.

[0015] In one optional embodiment, a coring drill bit is installed at the front end of the drilling rig, and the coring drill bit has a cylindrical hollow structure.

[0016] In one alternative implementation, the stabilizer bar integrates a motor drive module, which has a built-in drive motor and reduction gear for electrically adjusting the drilling rig feed speed and is linked to a torque sensor in the drilling rig mounting bracket.

[0017] In one optional embodiment, the drilling rig mounting bracket is equipped with a torque sensor to automatically stop the drilling rig feed when the drilling resistance exceeds a set threshold; the drilling rig is equipped with a drilling medium interface to adapt to water-cooled or air-cooled drilling media.

[0018] In one optional embodiment, the angle adjustment and support system further includes a parallel guide steel pipe and a vertical guide steel pipe, used to realize the translation of the drilling system in the horizontal or vertical direction, so as to perform continuous sampling of multiple parallel boreholes.

[0019] Secondly, the present invention also provides a method for directional core sampling of layered soft rock, employing a directional core sampling device, comprising the following steps: The angle adjustment and support system was assembled on site, the rigid rail was adjusted to be horizontal, the laser positioning system was installed and calibrated, and horizontal drilling was performed to obtain the initial rock core. The initial rock core was retrieved to confirm the lithology and water sensitivity, and the strike and dip angle of the bedding planes were measured. Calculate the target inclination angle α of the track based on the attitude of the bedding plane, adjust the height difference of the support, and calibrate using a slope ruler; Activate the laser positioning system, verify that the laser projection angle matches the target angle, and then tighten all fasteners. Depending on the lithology, water-cooled or air-cooled media are selected, and the drilling rig is started to drill directional cores. After a single hole is completed, the device is moved along a parallel or perpendicular guide steel pipe to perform continuous sampling.

[0020] In one optional implementation, in the step of starting the drilling rig to drill directional rock cores according to the rock type and matching the water-cooled or air-cooled medium, if the rock core is easily softened when exposed to water, then air-cooled drilling is used; if the rock core is stable when exposed to water, then water-cooled drilling is used. During the continuous sampling step after the single hole is completed, the translation interval is 5cm to 15cm along the parallel or vertical guide steel pipe translation device to ensure that adjacent holes do not interfere with each other. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a directional core sampling device for layered soft rock according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the back structure of a directional core sampling device for layered soft rock according to an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached figures: 1. Drilling rig; 2. Rigid track; 3. Drilling rig mounting bracket; 4. Laser emitter; 5. Track stabilizer bar; 6. Drilling rig feed handle; 7. Core drill bit; 8. Drilling medium interface; 9. Motor drive module. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0025] In geotechnical engineering, geological hazard assessment, and geological research, obtaining core samples that retain information about the original bedding structure is crucial. The mechanical properties of layered soft rocks (such as shale, mudstone, and slate) exhibit significant anisotropy; their strength and deformation characteristics are closely related to the strike and dip angle of the bedding planes. While traditional core drilling methods (such as those using vertical-shaft or fully hydraulic drilling rigs) can obtain core samples, they struggle to precisely control the angle between the drilling direction and the bedding planes, failing to meet the directional sampling requirements for core samples with specific attitudes (such as bedding-parallel, cross-bedding, and perpendicular bedding).

[0026] In the existing technology, there are some devices that attempt to solve the problem of on-site directional sampling, such as those using complex orientation adjustment mechanisms and fixed bases. However, these devices usually have the following drawbacks: the equipment is bulky, inconvenient to transport and install, and has poor adaptability, especially in uneven slopes or tunnels; the angle adjustment mechanism is complex, costly, and lacks adjustment accuracy and stability; and there is a lack of rapid and intuitive angle positioning and verification methods, which leads to deviations in the sampling angle.

[0027] The following is combined with Figures 1 to 2 The following describes embodiments of the present invention.

[0028] According to an embodiment of the present invention, in one aspect, a directional core sampling device for layered soft rock is provided, comprising a drilling system, an angle adjustment and support system, and a laser positioning system. The drilling system includes a drilling rig 1, a rigid rail 2, and a drilling rig mounting bracket 3. The drilling rig 1 is mounted on the rigid rail 2 via the drilling rig mounting bracket 3 and is capable of linear feed and retraction along the rigid rail 2. The angle adjustment and support system is composed of multiple scaffolding steel pipes connected by quick-connect couplings, including a bottom support frame and at least two parallel supports with independently adjustable heights. The rigid rail 2 overlaps and is fixed to the top crossbar of the supports. The laser positioning system includes two laser emitters 4, which are fixed to the side of the rigid rail 2 by clamps. The laser beam emitted by the laser emitters 4 is parallel to the extension direction of the rigid rail 2.

[0029] In this embodiment, the drilling system includes a drilling rig 1, a rigid rail 2, and a drilling rig mounting bracket 3. The rigid rail 2 serves as the guiding reference for the drilling rig 1. The drilling rig 1 is securely mounted on the rigid rail 2 via the drilling rig mounting bracket 3, enabling the drilling rig 1 to perform precise linear feed or retraction along the length of the rigid rail 2, thus ensuring the straightness of the drilling trajectory. The bracket body can be a rigid metal frame, with one or more sliders or rollers integrated at its bottom that match the cross-sectional shape of the rigid rail 2. Through these sliders or rollers, the entire bracket can engage or straddle the rigid rail 2 with low resistance, achieving smooth linear sliding.

[0030] The angle adjustment and support system provides stable support for the entire device and enables angle adjustment. This system consists of multiple standard-sized scaffolding steel pipes interconnected by quick-connect couplers, exhibiting a high degree of modularity and reconfigurability. Its main body includes a bottom support frame constructed of steel pipes, providing a stable foundation for the entire device. Above the bottom support frame, at least two parallel vertical supports are installed, and the height of each support can be adjusted independently. The two ends of the rigid track 2 are directly overlapped and fixed to the horizontal bars at the top of these two supports. By adjusting the height of the two supports individually, the spatial inclination angle of the rigid track 2 can be changed in the vertical plane.

[0031] The quick-connect coupler's main body is a high-strength cast iron or forged steel body with an internal cross-shaped slot for accommodating two perpendicularly intersecting steel pipes. The slot dimensions match standard scaffolding steel pipes. The quick-connect coupler also includes a locking mechanism, primarily consisting of a bolt penetrating the coupler body and a pair of wedge-shaped slips that mate with the bolt's ends. During operation, after placing the two steel pipes into the corresponding slots, no additional tools are needed; simply rotate the wing nut at the bolt end by hand or quickly pull the handle. Rotating the bolt drives the two wedge-shaped slips to move relative to each other along the inclined plane, thus firmly securing them against the outer wall of the steel pipes from the inside. This is a standard structure and will not be elaborated further here.

[0032] The laser positioning system is used for visual calibration and verification of a predetermined drilling trajectory. The system includes two high-precision laser emitters 4, which are respectively fixed to the two sides of a rigid track 2 using clamps. During installation, precise calibration is required to ensure that the laser beams emitted by both laser emitters 4 are strictly parallel to the extension direction of the rigid track 2. In this way, the line connecting the two laser beams projected onto the rock wall can visually represent the future drilling axis of the drill bit, providing a visible reference for angle adjustment.

[0033] The device in this embodiment achieves flexible and stable adjustment of the drilling rig angle through a modular support system, and realizes high-precision visual control of the drilling direction with the help of a laser positioning system, laying the foundation for obtaining directional rock cores with specific occurrences.

[0034] In one embodiment, the clamp of the laser positioning system is a detachable snap-fit ​​structure that adapts to the cross-sectional dimensions of the rigid rail 2, for quick installation and fixation of the laser emitter 4.

[0035] The main body of the clamp can be made of high-strength engineering plastic or aluminum alloy. Its core is a "C" or "U" shaped slot that matches the shape of the side of the rigid track 2. The inner contour dimensions of the slot can closely fit the rectangular or I-shaped cross-section of the rigid track 2, ensuring no wobbling after engagement. On one or both sides of the slot, there are elastic latches with protrusions. During installation, simply align the opening of the clamp's slot with the edge of the track side and press down firmly. The elastic latch will deform and slide under the pressure of the track side wall. When the protrusion passes the track edge, the latch rebounds, and its protruding part hooks onto the inside of the track, thus firmly locking the clamp onto the track. The entire process requires no tools. For disassembly, simply pinch or pull the release part of the latch to release it from the hook state, and the clamp can be removed from the track. On the outside of the clamp body, there is a device mounting interface, such as a cylindrical sleeve with a locking screw or a standard camera threaded hole, for reliably mounting and securing the main body of the laser emitter 4. For ease of initial calibration, the mounting interface can be connected to the card slot body via a directional joint with a finely adjustable angle or a rotary base with a scale, allowing for adjustment of the projection angle of the laser emitter 4 within a small range to ensure that the laser beam is strictly parallel to the track.

[0036] In one embodiment, the drilling system further includes two track stabilizing rods 5, which are arranged horizontally and connected to the two ends of the rigid track 2 respectively.

[0037] In one embodiment, the drilling rig fixed bracket 3 is provided with a drilling rig feed handle 6. The handle is a cylindrical grip structure and is mechanically linked with the drilling rig spindle. It is used to manually control the drilling rig 1 to feed or retract along the rigid track 2.

[0038] Specifically, a drive gear can be connected to the rear end of the handle's rotating shaft. On one side of the rigid track 2, a rack of the same length as the track is fixedly installed. The drive gear and the rack are always engaged. When the operator rotates the handle clockwise or counterclockwise, the rotational motion is converted into precise linear motion of the drill rig fixed support 3 (together with the drill rig 1 on it) along the rigid track 2 through the transmission of the gear and rack.

[0039] The handle is an ergonomically designed cylindrical grip structure, typically made of a metal rod, with a surface that may be knurled for a non-slip grip or covered with a soft rubber layer to provide a comfortable and secure hold. The handle is mounted via a robust radial bearing to an easily accessible position at the front or side of the drill rig mounting bracket 3.

[0040] In one embodiment, a core drill bit 7 is installed at the front end of the drilling rig 1. The core drill bit 7 has a cylindrical hollow structure. When the drilling rig 1 drives the drill bit to rotate and feed into the rock mass, the annular cutting edge at the front end cuts out annular gaps, while the cylindrical rock mass (i.e., the rock core) surrounded by these gaps remains relatively intact. As the drill bit continues to advance, the unbroken rock core column gradually enters and remains within the hollow cavity of the drill bit, thus being protected and preventing complete crushing. After completing a section of feed, the drill bit is pulled out, and a complete cylindrical rock core sample can be obtained from its hollow cavity.

[0041] In one embodiment, the stabilizer bar integrates a motor drive module 9, which has a built-in drive motor and reduction gear for electrically adjusting the drilling rig feed speed and is linked to a torque sensor in the drilling rig fixed bracket 3.

[0042] The torque sensor is directly integrated into the power transmission spindle of drilling rig 1. Specifically, the sensor employs a strain gauge measurement principle, and its elastic body is designed as a special structure within the spindle. When the drill bit cuts the rock, the resulting counter-torque acts on the spindle, causing a slight torsional deformation in this elastic body. The resistance of the strain gauges attached to the surface of the elastic body changes accordingly, thus outputting an electrical signal proportional to the magnitude of the torque.

[0043] The electrical signal is transmitted to a signal processing and controller fixed to the drilling rig's mounting bracket 3. The controller has a preset torque safety threshold set according to the rock type and drill bit size. During drilling, the controller continuously compares the measured torque with the threshold. If the torque exceeds the preset threshold due to drill bit jamming, encountering hard interlayers, or excessive feed rate, the controller immediately sends a stop command to the drive system. If it is motor-driven, the motor power is directly cut off and the brakes are applied; if it is manual feed, an audible and visual alarm may be triggered to prompt the operator to stop applying force.

[0044] In addition, drilling rig 1 is equipped with drilling medium interface 8. This interface is a standard quick-connect coupling, which can be quickly connected to the water supply pipe from the water pump or the air supply pipe from the air compressor, depending on the confirmed lithology and water sensitivity, to achieve water-cooled or air-cooled drilling.

[0045] In one embodiment, the drilling rig mounting bracket 3 is equipped with a torque sensor to automatically stop the drilling rig feed when the drilling resistance exceeds a set threshold; the drilling rig 1 is equipped with a drilling medium interface 8 to adapt to water-cooled or air-cooled drilling media.

[0046] The drilling rig 1 has one or more standard drilling medium interfaces 8 on its body. These interfaces are typically quick-connect self-locking couplings, such as pagoda couplings or quick-connect pneumatic couplings. One interface is used to connect to a water source (such as a water pump outlet pipe) for water-cooled drilling, suitable for water-stable rock formations, serving to cool the drill bit, lubricate, and remove slag. The other interface (or shared via a switching valve) is used to connect to an air source (such as an air compressor outlet pipe) for air-cooled drilling, specifically for drilling into sensitive rock formations that are easily softened or disintegrated by water (such as certain mudstones and shale), using dry air as the cooling and slag removal medium to maximize the protection of the original core structure.

[0047] In one embodiment, the angle adjustment and support system further includes a parallel guide steel pipe and a vertical guide steel pipe, used to realize the translation of the drilling system in the horizontal or vertical direction to perform continuous sampling of multiple parallel boreholes.

[0048] The angle adjustment and support system further integrates a guide translation mechanism, the core of which consists of parallel guide steel pipes and vertical guide steel pipes. This mechanism enables the entire drilling system to move accurately and smoothly in the horizontal or vertical direction without changing the precisely adjusted spatial angle of the drilling system, thereby efficiently and with high parallelism completing a series of continuous sampling operations.

[0049] According to an embodiment of the present invention, another aspect provides a method for directional core sampling of layered soft rock, employing a directional core sampling device, comprising the following steps: The angle adjustment and support system was assembled on site, the rigid rail 2 was adjusted to be horizontal, the laser positioning system was installed and calibrated, and horizontal drilling was performed to obtain the initial rock core. Near the selected sampling point, an angle adjustment and support system was assembled on-site using modular scaffolding steel pipes and quick-connect couplers. Using tools such as a spirit level, the rigid track 2 installed on it was initially adjusted to a horizontal state. Subsequently, the laser transmitter 4 and its clamps of the laser positioning system were installed, and calibration was performed to ensure that the emitted laser beam was strictly parallel to the horizontal track. Based on field experience or preliminary geological data, a drilling medium was initially selected. After completing the equipment connection, at the predetermined starting point on the rock face, the drilling rig 1 was controlled to perform the first drilling along the horizontal track to obtain an initial rock core.

[0050] The initial rock core was retrieved to confirm the lithology and water sensitivity, and the strike and dip angle of the bedding planes were measured. Carefully remove the initial rock core. First, visually observe its integrity and mineral composition, and confirm the basic lithology of the rock mass and its sensitivity to water through methods such as water dripping tests. Then, using surveying tools such as a geological compass, directly measure and accurately record the strike and dip angle of the bedding planes or foliation planes contained within the core. The crucial occurrence data obtained in this step is the geological basis for all subsequent angle calculations.

[0051] Calculate the target inclination angle α of the track based on the attitude of the bedding plane, adjust the height difference of the support, and calibrate using a slope ruler; Based on the specific sampling angle required for engineering or scientific research, and the natural attitude of the bedding planes measured in the above steps, the required spatial inclination angle of the rigid track 2, i.e., the target inclination angle α, is determined through geometric calculation. After the calculation is completed, the quick-connect fasteners of the relevant supports in the support system are loosened, and the height of each support is changed by adjusting the adjustable legs or pads of each support, so that the plane of the rigid track 2 erected on it forms the calculated angle α with the horizontal plane. During this process, a slope gauge can be used for preliminary angle calibration and verification.

[0052] Activate the laser positioning system, verify that the laser projection angle matches the target angle, and then tighten all fasteners. After the initial attitude adjustment of the device is completed, the laser positioning system is activated. Two parallel laser beams are projected onto the surface of the rock wall to be drilled, forming a visible optical reference line. Using a geological compass or slope ruler, the attitude (i.e., its strike and dip angle) of the laser projection line on the rock wall is measured in the field. This measured attitude is compared and verified with the theoretical projection angle calculated based on the target dip angle α and the spatial geometric relationship of the sampling points. If there is a deviation, the support bracket is finely adjusted until the laser projection angle is completely consistent with the theoretical value. After confirming that there is no error, all loosened quick-connect fasteners in the angle adjustment and support system are immediately tightened to finally lock the attitude of the entire device (especially the track inclination angle).

[0053] Depending on the lithology, water-cooled or air-cooled medium is selected, and drilling rig 1 is started to drill directional rock cores. After a single hole is completed, the device is moved along a parallel or perpendicular guide steel pipe to perform continuous sampling.

[0054] After the first directional borehole is completed, drill rig 1 is withdrawn from the hole. If deeper core samples are needed in the same borehole, drilling can continue by adding drill rods. Once all samples for a single borehole are collected, there is no need to readjust the device angle. The entire drilling system (including drill rig 1, track, and support frame) is slid horizontally along the pre-set parallel guide pipe, or raised and lowered along the vertical guide pipe after completing a row of boreholes, to move to the next predetermined position. The movement distance ensures that new boreholes do not interfere with completed boreholes.

[0055] In one embodiment, during the step of drilling rig 1 to obtain directional rock cores, depending on the rock type and whether water-cooled or air-cooled medium is used, if the rock core is easily softened by water, then air-cooled drilling is used; if the rock core is stable by water, then water-cooled drilling is used. After a single borehole is completed, the continuous sampling process is carried out by moving the device along the parallel or vertical guide steel pipe. The moving interval is 5cm to 15cm to ensure that adjacent boreholes do not interfere with each other.

[0056] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A directional core sampling device for layered soft rock, characterized in that, include: The drilling system includes a drilling rig (1), a rigid rail (2) and a drilling rig mounting bracket (3). The drilling rig (1) is mounted on the rigid rail (2) via the drilling rig mounting bracket (3) and is capable of linear feed and retraction along the rigid rail (2). Angle adjustment and support system, consisting of multiple scaffold steel pipes connected by quick-connect fasteners, includes a bottom support frame and at least two parallel supports with independently adjustable heights. The rigid rail (2) overlaps and is fixed to the top crossbar of the support. The laser positioning system includes two laser emitters (4) which are fixed to the side of the rigid track (2) by clamps. The laser beam emitted by the laser emitters (4) is parallel to the extension direction of the rigid track (2).

2. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The clamp of the laser positioning system is a detachable snap-fit ​​structure that is adapted to the cross-sectional dimensions of the rigid rail (2) for quick installation and fixation of the laser emitter (4).

3. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The drilling system also includes two track stabilizing rods (5), which are arranged horizontally and connected to the two ends of the rigid track (2).

4. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The drilling rig fixed bracket (3) is provided with a drilling rig feed handle (6). The handle is a cylindrical grip structure and is mechanically linked with the drilling rig spindle. It is used to manually control the drilling rig (1) to feed or retract along the rigid track (2).

5. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The front end of the drilling rig (1) is equipped with a core drill bit (7), which is a cylindrical hollow structure.

6. The directional core sampling device for layered soft rock according to claim 3, characterized in that, The track stabilizer bar (5) integrates a motor drive module (9), which has a built-in drive motor and reduction gear to realize electric adjustment of the drilling rig feed speed and is linked with the torque sensor in the drilling rig fixed bracket (3).

7. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The drilling rig fixed bracket (3) is equipped with a torque sensor, which is used to automatically stop the drilling rig feed when the drilling resistance exceeds the set threshold; the drilling rig (1) is equipped with a drilling medium interface (8), which is used to adapt to water-cooled or air-cooled drilling media.

8. The directional core sampling device for layered soft rock according to claim 1, characterized in that, The angle adjustment and support system also includes parallel guide steel pipes and vertical guide steel pipes, which are used to realize the translation of the drilling system in the horizontal or vertical direction, so as to continuously sample multiple parallel boreholes.

9. A method for directional core sampling of layered soft rock, employing the directional core sampling device as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Assemble the angle adjustment and support system on site, adjust the rigid rail (2) to the horizontal, install and calibrate the laser positioning system, and perform horizontal drilling to obtain the initial rock core; The initial rock core was retrieved to confirm the lithology and water sensitivity, and the strike and dip angle of the bedding planes were measured. Calculate the target inclination angle α of the track based on the attitude of the bedding plane, adjust the height difference of the support, and calibrate using a slope ruler; Activate the laser positioning system, verify that the laser projection angle matches the target angle, and then tighten all fasteners. Depending on the lithology, water-cooled or air-cooled medium is selected, and the drilling rig is started (1) to drill directional rock cores; After a single hole is completed, the device is moved along a parallel or perpendicular guide steel pipe to perform continuous sampling.

10. The method for directional core sampling of layered soft rock according to claim 9, characterized in that, In the step of starting the drilling rig (1) to drill directional rock cores according to the rock type and matching the water-cooled or air-cooled medium, if the rock core is easily softened by water, then air-cooled drilling is used; if the rock core is stable by water, then water-cooled drilling is used. During the continuous sampling step after the single hole is completed, the translation interval is 5cm to 15cm along the parallel or vertical guide steel pipe translation device to ensure that adjacent holes do not interfere with each other.

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