Water-rich soft rock sampling and mechanical property in-situ testing device

Abstract

The invention relates to the technical field of sampling and testing, and discloses a water-rich soft rock sampling and mechanical property in-situ testing device which comprises a base and a reaction frame hinged to the periphery of the base, a protective shell is installed at the bottom of the base, a transmission shaft and a framework are coaxially arranged in the center of the protective shell, and the lower section of the framework is sleeved with a liftable sampling assembly. The transmission shaft penetrates through the framework and then is sequentially connected with the flow limiting assembly and the drill bit. The top of the framework is provided with a transmission assembly used for driving the flow limiting assembly to rotate. When the through holes in the surface of the gear ring are switched to be aligned with the flow guide pipes symmetrically distributed on the front and back sides of the bottom plug disc, water flow carrying soft rock in the annular drainage groove can only enter the communicated flow guide pipes through the through holes of the gear ring at the moment and then is discharged into a liquid cavity between the top plug disc and the sealing plate through the flow guide pipes, the liquid cavity is expanded, and sampling operation is completed; rapid switching of well drilling drainage and soft rock sampling is achieved, dual-mode integrated equipment is formed, and in-situ testing of mechanical properties is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of sampling and testing, and more particularly to an in-situ testing device for sampling water-rich soft rock and conducting mechanical property tests. Background Art

[0002] In water-rich soft rock mines, mining activities can lead to significant creep characteristics, such as large, nonlinear deformation and prolonged deformation. The high water content and low strength of water-rich soft rock make it susceptible to damage during sampling and sample preparation. Therefore, specialized soft rock sampling tools are required. Currently, soft rock sampling relies primarily on a series of specialized tools, including drilling equipment, drainage devices, and sampling instruments. First, a specialized drill body is used to break up the water-rich soft rock until the predetermined sampling depth is reached. During this stage, to ensure smooth drilling, groundwater in the water-rich soft rock must be drained through a drainage pipe to prevent excessive water accumulation from affecting drilling efficiency. Once the target depth is reached, the operator removes the drilling tool and replaces it with a specialized sampling tool (such as a core barrel or other type of coring device) placed into the existing wellbore for sample collection. After sampling, the soft rock sample must be properly sealed and stored and quickly transferred to a laboratory or on-site in-situ testing system for further analysis and testing.

[0003] However, due to the time lag between the start of drainage and the final completion of sampling, this traditional sampling method struggles to achieve the goals of immediate drainage and rapid sampling. Furthermore, the entire process involves multiple steps, resulting in relatively low overall work efficiency. Furthermore, the actual sampling location may deviate to a certain degree from the initially set drilling point, directly impacting the accuracy of the measurement results—especially for studies aimed at assessing the physical properties of soft rock, such as the lateral pressure it withstands in its natural state.

[0004] Therefore, the present invention proposes a water-rich soft rock sampling and mechanical property in-situ testing device to achieve rapid switching between drilling drainage and soft rock sampling, forming a dual-mode integrated device, which is convenient for in-situ testing of mechanical properties. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides a water-rich soft rock sampling and mechanical property in-situ testing device to solve the problem existing in the above-mentioned background technology of how to achieve rapid switching between drilling drainage and soft rock sampling, forming a dual-mode integrated equipment, and facilitating in-situ testing of mechanical properties.

[0006] The present invention provides the following technical solution: an in-situ device for sampling and testing mechanical properties of water-rich soft rock, comprising a base and a reaction frame hingedly connected to the base. A protective shell is installed at the bottom of the base, a transmission shaft and a frame are coaxially arranged at the center of the protective shell, a lower section of the frame is sleeved with a liftable sampling assembly, the transmission shaft passes through the frame and is sequentially connected to a current limiting assembly and a drill bit, and a transmission assembly for transmitting the rotational motion of the current limiting assembly is provided at the top of the frame. The transmission shaft includes a drill rod and a transmission sleeve rotatably sleeved on its outer wall; the skeleton includes a bottom plug disc, a guide tube, a top plug disc, a connecting rod and a bearing platform, wherein the bottom plug disc, the top plug disc and the bearing platform are coaxially distributed from bottom to top; the guide tubes arranged on the front and rear sides of the transmission shaft are fixedly penetrated through the bottom plug disc and the top plug disc; the sampling assembly includes a sampling barrel, a sealing plate and a drain pipe, wherein the top and bottom walls of the sampling barrel are movably penetrated by the connecting rod and the guide tube respectively, so that the sampling barrel can move upward along the guide tube and the connecting rod; the top end of the inner cavity of the sampling barrel is equipped with a sealing plate; The current limiting assembly includes a gear ring, a planetary gear and a sun gear, wherein the gear ring is rotatably arranged above the drill bit, and the retaining ring on the bottom wall of the gear ring is slidably connected to the retaining groove on the top wall of the drill bit. The center of the gear ring is provided with a sun gear fixedly sleeved on the outer wall of the bottom end of the transmission sleeve, and circumferentially distributed planetary gears are provided between the gear ring and the sun gear. The rotating sun gear transmits torque to the outer gear ring through the annularly distributed planetary gears, causing the gears to rotate around the axis until the through holes on the surface of the gear ring are switched to align with the guide pipes symmetrically distributed front and back with the bottom plug disk. At this time, the water flow carrying soft rock in the annular drainage groove can only enter the connected guide pipe through the through holes of the gear ring, and then be discharged into the liquid cavity between the top plug disk and the sealing plate by the guide pipe. The liquid cavity expands, and the sampling operation is completed to achieve rapid switching between drilling drainage and soft rock sampling.

[0007] Furthermore, the top end of the connecting rod is fixedly connected to the supporting platform, and the bottom end of the connecting rod is movably passed through the sampling tube and the sealing plate and is fixedly connected to the top plug plate. The supporting platform is vertically slidably connected to the inner cavity of the protective shell, and the supporting platform is rotatably sleeved in the slot of the transmission sleeve, so that the skeleton and the sampling assembly will sink together with the transmission shaft and will not be affected by its rotation, that is, the skeleton and the sampling assembly only appear to move up and down.

[0008] Furthermore, a liquid cavity with variable volume is provided between the top plug disc and the sealing plate for collecting soft rock samples. A drainage pipe is provided in the side wall of the sampling tube. The bottom end of the drainage pipe passes through the bottom plug disc, while the top end does not exceed the top plug disc.

[0009] Furthermore, the sampling assembly further comprises a valve body, which is assembled on the top end of the outer wall of the sampling tube. After the sampling, the soft rock sample in the liquid cavity can be emptied by opening the valve body.

[0010] Furthermore, the convex ring on the surface of the drill rod can be nested in the bite cavity at the top of the transmission sleeve, so that the drill rod can carry the transmission sleeve to perform lifting movements together, and the drill rod and the transmission sleeve can rotate independently without interfering with each other.

[0011] Furthermore, a plurality of high-precision pressure sensors are evenly arranged on the inner wall of the sampling tube, which can measure the lateral pressure exerted on the soft rock sample in the in-situ state in real time. Displacement sensors are set in the sealing plate and the top plug plate to measure the axial displacement of the soft rock sample when an axial load is applied.

[0012] Furthermore, the transmission assembly includes a driven gear, a driving gear and a motor, wherein the driven gear is fixedly sleeved on the outer wall of the transmission sleeve, the driven gear is engaged with the driving gear arranged coplanar therewith, the driving gear is coaxially assembled with the output shaft of the motor, and the base of the motor is installed on the supporting platform.

[0013] Furthermore, the slot of the drill bit is assembled with the drill rod, which is a composite structure. The front end is a carbide cutting edge for crushing soft rock, and the rear end is provided with a drainage groove and an annular drainage groove connected thereto, which can discharge water in the water-rich soft rock in time during drilling, thereby avoiding interference of water on the drilling process and subsequent sampling.

[0014] Furthermore, the left and right side walls of the protective shell are also equipped with a limiting assembly, and the limiting assembly includes a screw, a shaft seat and a limiting block, wherein the shaft seat is assembled on the outside of the protective shell, the top end of the screw is rotatably sleeved in the shaft seat, and the surface thread of the screw is sleeved with the limiting block. By rotating the screw, the moving position of the limiting block in the sliding groove of the side wall of the protective shell can be adjusted to limit the lifting position of the sampling tube.

[0015] Furthermore, the output shaft of the drilling rig can be assembled with the drill rod through a coupling to provide output torque for the drill rod, so that the drill rod can transmit the power output by the drilling rig to the drill bit and drive it to continue to go deeper to achieve drilling operations. The top of the base is also equipped with a loading device. The hydraulic jack can pass through the perforations on the base, protective shell, bearing platform and sampling tube in sequence, and apply axial load to the soft rock sample between the sealing plate and the top plug disc according to the set loading rate, simulating the stress state of soft rock in actual engineering.

[0016] Technical effects and advantages of the present invention: The present invention cooperates with the skeleton, sampling assembly, transmission assembly and current limiting assembly to facilitate the water in the water-rich soft rock formation to enter the annular drainage groove through the drainage groove on the side wall of the drill bit during the drilling process, and then enter the connected drainage pipe through the through hole of the gear ring, and then be discharged into the water collection tank through the hose connected to the top of the drainage pipe. When the drill bit drills into the predetermined sampling depth, the control equipment is changed to control the output shaft of the motor to drive the driving gear to rotate, and then drive the driven gear, so that the driven gear, transmission sleeve and sun gear rotate coaxially as a whole, and the rotating sun gear The male gear transmits the torque to the outer gear ring through the annularly distributed planetary gears, causing the teeth to rotate around the axis until the through holes on the gear ring surface are switched to align with the guide pipes symmetrically distributed in front and back of the bottom plug disc. At this time, the water carrying soft rock in the annular drainage groove can only enter the connected guide pipes through the through holes of the gear ring, and then be discharged into the liquid cavity between the top plug disc and the sealing plate by the guide pipe. The liquid cavity expands and the sampling operation is completed, so as to realize the rapid switching between drilling drainage and soft rock sampling, forming a dual-mode integrated equipment, which is convenient for in-situ testing of mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0018] Figure 2 It is a schematic diagram of the overall structure of the present invention and its partial cross-section.

[0019] Figure 3 It is a schematic diagram of the connection structure of the transmission shaft, skeleton, transmission assembly, sampling assembly and limiting assembly of the present invention.

[0020] Figure 4 For the present invention Figure 3 Schematic diagram of the structure at point A in the middle.

[0021] Figure 5 For the present invention Figure 3 Schematic diagram of the structure at point B in the middle.

[0022] Figure 6 It is a schematic diagram of the connection structure of the transmission shaft, skeleton, sampling assembly, current limiting assembly and drill bit of the present invention.

[0023] Figure 7 For the present invention Figure 6 Schematic diagram of the structure at point C in the middle.

[0024] Figure 8 This is a schematic diagram of the disassembled structure of the transmission shaft, skeleton, sampling assembly, current limiting assembly and drill bit of the present invention.

[0025] Figure 9 For the present invention Figure 8 Schematic diagram of the structure at point D in the middle.

[0026] Figure 10 For the present invention Figure 8 Schematic diagram of the structure at E in the middle.

[0027] The accompanying drawings are marked as follows: 1. Base; 2. Reaction frame; 3. Protective shell; 4. Transmission shaft; 401. Drill rod; 402. Transmission sleeve; 5. Skeleton; 501. Bottom plug plate; 502. Guide tube; 503. Top plug plate; 504. Connecting rod; 505. Support platform; 6. Sampling assembly; 601. Sampling tube; 602. Sealing plate; 603. Valve body; 604. Drain pipe; 7. Transmission assembly; 701. Driven gear; 702. Driving gear; 703. Motor; 8. Current limiting assembly; 801. Gear ring; 802. Planetary gear; 803. Sun gear; 9. Drill bit; 10. Limiting assembly; 1001. Screw; 1002. Shaft seat; 1003. Limiting block. DETAILED DESCRIPTION

[0028] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. In addition, the forms of the various structures described in the following embodiments are merely examples. The in-situ testing device for sampling and mechanical properties of water-rich soft rocks involved in the present invention is not limited to the various structures described in the following embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] Reference Figure 1-10 The present invention provides an in-situ testing device for sampling and mechanical properties of water-rich soft rock, comprising a base 1 and a reaction frame 2 hingedly connected to the base 1. A protective shell 3 is installed at the bottom of the base 1. A transmission shaft 4 and a skeleton 5 are coaxially arranged at the center of the protective shell 3. A liftable sampling component 6 is sleeved on the lower section of the skeleton 5. The transmission shaft 4 passes through the skeleton 5 and is sequentially connected to a current limiting component 8 and a drill bit 9. A transmission component 7 for transmitting the rotational motion of the current limiting component 8 is provided on the top of the skeleton 5.

[0030] In this embodiment, it should be specifically explained that the transmission shaft 4 includes a drill rod 401 and a transmission sleeve 402 rotatably sleeved on its outer wall, and the convex ring on the surface of the drill rod 401 can be nested in the bite cavity at the top of the transmission sleeve 402, so that the drill rod 401 can carry the transmission sleeve 402 for joint lifting and lowering motion, and the drill rod 401 and the transmission sleeve 402 can rotate independently without interfering with each other; A drilling rig is mounted on the top of the base 1. A hydraulically driven lightweight drilling rig is selected, which has adjustable drilling speed and torque output functions. Its maximum drilling depth can reach 30 meters, which can flexibly adapt to the sampling requirements of water-rich soft rocks at different depths. The output shaft of the drilling rig can be assembled with the drill rod 401 through a coupling, providing output torque to the drill rod 401, so that the drill rod 401 can transmit the power output by the drilling rig to the drill bit 9 and drive it to continue to drill deeper, thereby achieving the drilling operation; The top of the base 1 is also equipped with a loading device, such as a hydraulic jack. The maximum loading force of the hydraulic jack can reach 100 kN. The hydraulic jack can pass through the base 1, the protective shell 3, the bearing platform 505 and the through-holes on the sampling tube 601 in sequence, and apply an axial load to the soft rock sample between the sealing plate 602 and the top plug plate 503 according to the set loading rate, simulating the stress state of soft rock in actual engineering. It is fixed on the ground or the surrounding stable rock mass with the reaction frame 2 to provide reliable reaction support for loading.

[0031] Reference Figure 3-7 ,and Figure 9-10 The skeleton 5 includes a bottom plug disc 501, a guide tube 502, a top plug disc 503, a connecting rod 504 and a bearing platform 505, wherein the bottom plug disc 501, the top plug disc 503 and the bearing platform 505 are coaxially distributed from bottom to top, and the guide tube 502 arranged on the front and rear sides of the transmission shaft 4 is fixedly penetrated through the bottom plug disc 501 and the top plug disc 503, the top end of the connecting rod 504 is fixedly connected to the bearing platform 505, and the bottom end of the connecting rod 504 is movably penetrated through the sampling tube 601 and the sealing plate 602 and is fixedly connected to the top plug disc 503, the bearing platform 505 is vertically slidably connected to the inner cavity of the protective shell 3, and the bearing platform 505 is rotatably sleeved in the card slot of the transmission sleeve 402, so that the skeleton 5 and the sampling assembly 6 will sink together with the transmission shaft 4 and will not be affected by its rotation, that is, the skeleton 5 and the sampling assembly 6 only move up and down; The sampling assembly 6 includes a sampling tube 601, a sealing plate 602 and a drainage pipe 604, wherein the top and bottom walls of the sampling tube 601 are movably penetrated by the connecting rod 504 and the guide tube 502 respectively, so that it can move upward along the guide tube 502 and the connecting rod 504. The top end of the inner cavity of the sampling tube 601 is equipped with a sealing plate 602, and a liquid chamber with a variable volume is provided between the top plug plate 503 and the sealing plate 602 for collecting soft rock samples. Drainage pipes 604 are symmetrically distributed on the left and right sides of the sampling tube 601. The bottom end of the drainage pipe 604 passes through the bottom plug plate 501, and the top end does not exceed the top plug plate 503. During the drilling process, water in the water-rich soft rock formation can enter the annular drainage groove through the drainage groove on the side wall of the drill bit 9, and then pass through the through hole of the gear ring 801 into the connected drainage pipe 604, and is discharged into the water collecting tank through the hose connected to the top of the drainage pipe 604.

[0032] In this embodiment, it should be specifically noted that multiple high-precision pressure sensors are evenly arranged on the inner wall of the sampling tube 601, which can measure the lateral pressure of the soft rock sample in situ in real time. The pressure measurement range is 0-5 MPa and the accuracy reaches 0.01 MPa. The sensors are connected to the data acquisition instrument via a data cable, which can transmit the pressure data in real time. Displacement sensors are installed in the sealing plate 602 and the top plug plate 503 to measure the axial displacement of the soft rock sample when an axial load is applied. The measurement accuracy can reach 0.01 mm. The displacement sensors are also connected to the data acquisition instrument to achieve synchronous acquisition of displacement data. The transmission shaft 4 movably passes through the center of the bottom wall of the bottom plug disc 501, so that the transmission sleeve 402 does not interfere with the bottom plug disc 501 when rotating, and the connection between the two is sealed; The sampling assembly 6 further includes a valve body 603 , which is mounted on the top of the outer wall of the sampling tube 601 . After sampling, the soft rock sample in the liquid cavity can be emptied by opening the valve body 603 . When the sampling tube 601 is lowered to the lowest depth, the top end of the drainage pipe 604 should still be above the ground surface to avoid it being buried, thereby affecting the drainage capacity of the equipment; In this article, all the positional relationships we discuss about front, back, left, and right are based on Figure 1 or Figure 3 These directions are defined by the perspective presented. They have no actual geographical or physical meaning. They are merely a reference framework to help readers understand the content of the article more intuitively. In this way, we can more clearly show the relative position relationship between the various parts, making the entire discussion process easier to understand and follow. Please note that this custom direction identification is only for internal use in this article and does not represent any absolute direction or position in the real world.

[0033] Reference Figure 3-4 ,and Figure 7-10 The transmission assembly 7 includes a driven gear 701, a driving gear 702 and a motor 703, wherein the driven gear 701 is fixedly sleeved on the outer wall of the transmission sleeve 402, and the driven gear 701 is meshed with the driving gear 702 arranged coplanar therewith. The driving gear 702 is coaxially assembled with the output shaft of the motor 703, and the base of the motor 703 is mounted on the supporting platform 505. The output shaft of the motor 703 can drive the driving gear 702 to rotate, thereby transmitting the driven gear 701 to adjust the rotation angle of the driven gear 701, the transmission sleeve 402 and the sun gear 803; The current limiting component 8 includes a gear ring 801, planetary gears 802 and a sun gear 803, wherein the gear ring 801 is rotatably arranged above the drill bit 9, and the retaining ring on the bottom wall of the gear ring 801 is slidably connected to the retaining groove on the top wall of the drill bit 9. The center of the gear ring 801 is provided with a sun gear 803 fixedly sleeved on the outer wall of the bottom end of the transmission sleeve 402. There are circumferentially distributed planetary gears 802 between the gear ring 801 and the sun gear 803. The planetary gears 802 are meshed with the two at the same time, and the planetary gears 802 can rotate through the rotating shaft fixed to the bottom wall of the bottom plug disc 501. The surface of the gear ring 801 is provided with symmetrically distributed through holes, which rotate The sun gear 803 transmits the torque to the outer gear ring 801 through the annularly distributed planetary gears 802, causing the gear ring 801 to rotate around the axis until the through holes on the surface of the gear ring 801 are switched to align with the guide tubes 502 symmetrically distributed in front and back of the bottom plug disc 501. At this time, the water carrying soft rock in the annular drainage groove can only enter the connected guide tubes 502 through the through holes of the gear ring 801, and then be discharged into the liquid cavity between the top plug disc 503 and the sealing plate 602 by the guide tube 502. The liquid cavity expands and the sampling operation is completed, so as to realize the rapid switching between drilling drainage and soft rock sampling, forming a dual-mode integrated equipment.

[0034] In this embodiment, it is necessary to specifically explain that the slot of the drill bit 9 is assembled with the drill rod 401, which is a specially made composite structure. The front end is a carbide cutting edge for crushing soft rock, and the rear end is provided with a drainage groove and an annular drainage groove connected thereto. During drilling, water in the water-rich soft rock can be promptly discharged to prevent water from interfering with the drilling process and subsequent sampling. The left and right side walls of the protective shell 3 are also equipped with a limiting assembly 10, which includes a screw 1001, a shaft seat 1002 and a limiting block 1003, wherein the shaft seat 1002 is assembled on the outside of the protective shell 3, and the top end of the screw 1001 is rotatably sleeved in the shaft seat 1002, and the surface thread of the screw 1001 is sleeved with the limiting block 1003. By rotating the screw 1001, the moving position of the limiting block 1003 in the slide groove of the side wall of the protective shell 3 can be adjusted to limit the lifting position of the sampling tube 601, and the slide groove and the screw 1001 are staggered, so that the slide groove of the side wall of the protective shell 3 can also allow the hose connected to the drain pipe 604 to enter.

[0035] Working principle of the present invention: By adjusting the angle of the reaction frame 2 and stabilizing the device on the surface, the drilling rig is started, and the drilling speed and torque output can be adjusted, so that the output shaft of the drilling rig can drive the drill rod 401 connected thereto and the drill bit 9 assembled at the bottom end of the drill rod 401 to rotate coaxially through the coupling. The rotating drill bit 9 continuously breaks the water-rich soft rock, so that the drill rod 401 can transmit the power output by the drilling rig to the drill bit 9 and drive it to continue to penetrate deeper, thereby realizing the drilling operation. During this period, the skeleton 5, sampling assembly 6, transmission assembly 7 and current limiting assembly 8 will sink together. At this time, the gear ring 80 The through holes symmetrically distributed on the surface are aligned with the drainage pipes 604 in the left and right walls of the sampling tube 601, so that during drilling, water from the water-rich soft rock formation can flow from the drainage grooves on the side walls of the drill bit 9 into the annular drainage grooves on its top wall. The water in the annular drainage grooves can then flow through the through holes in the gear ring 801 into the connected drainage pipes 604, and then be discharged into the water collection tank through the external hose at the top of the drainage pipes 604. This is used to collect water discharged from the water-rich soft rock during drilling, preventing water accumulation in the site and causing interference with the drilling process and subsequent sampling, thereby achieving drainage operations. When the drill bit 9 drills into the predetermined sampling depth, the control device is changed at this time, specifically starting the motor 703, and then the output shaft of the motor 703 drives the driving gear 702 to rotate, and the rotating driving gear 702 transmits the driven gear 701 meshing with it, so that the driven gear 701, the transmission sleeve 402 and the sun gear 803 rotate coaxially as a whole, and the rotating sun gear 803 transmits the torque force to the outer gear ring 801 through the annularly distributed planetary gears 802, causing the gear ring 801 to rotate around the axis until the through hole on the surface of the gear ring 801 switches to align with the guide pipe 502 symmetrically distributed front and back with the bottom plug plate 501. At this time, the water carrying soft rock in the annular drainage trough can only enter the connected guide pipe through the through hole of the gear ring 801. 502, and then discharged into the liquid cavity between the top plug plate 503 and the sealing plate 602 through the guide pipe 502. At the same time, multiple high-precision pressure sensors are evenly arranged on the inner wall of the sampling tube 601, which can measure the lateral pressure of the soft rock sample in the in-situ state in real time. As the sampling volume of the liquid cavity increases, the sealing plate 602 is pushed up by the hydraulic pressure, so that the sampling tube 601 can be lifted upward along the connecting rod 504 as a whole, that is, the liquid cavity expands until the sampling tube 601 touches the bottom wall of the limit block 1003 at the preset position. It is determined that the soft rock sample has reached the predetermined collection volume at this time, the drilling rig is stopped, and the direction of the output shaft of the motor 703 is switched until the gear ring 801 blocks the bottom end of the guide pipe 502 again, the liquid cavity is sealed, and the sampling operation is completed; Subsequently, the hydraulic jack is activated to penetrate the top wall of the sampling tube 601 and press the sealing plate 602, and an axial load is applied to the soft rock sample in the liquid cavity according to the set loading rate, simulating the stress condition of the soft rock in the in-situ state. At the same time, the displacement sensors installed in the sealing plate 602 and the top plug plate 503 can measure the axial displacement of the soft rock sample when the axial load is applied. The pressure sensor and the displacement sensor collect the stress and deformation data of the sample in real time, and transmit them to the data acquisition instrument for recording and storage, thereby finally completing the sampling and in-situ testing of the mechanical properties of the water-rich soft rock. The relevant data obtained can provide a reliable basis for the subsequent design and construction of water-rich soft rock-related projects.

[0036] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or modifications within the technical scope disclosed by the present invention; according to the technical plan and its improved conception of the present invention, these should be included under the protection of the present invention.

Claims

1. A device for sampling and testing mechanical properties of water-rich soft rock in situ, comprising a base (1) and a reaction frame (2) hingedly connected to the base, characterized in that: A protective shell (3) is installed at the bottom of the base (1), a transmission shaft (4) and a frame (5) are coaxially arranged at the center of the protective shell (3), a lower section of the frame (5) is sleeved with a liftable sampling assembly (6), the transmission shaft (4) passes through the frame (5) and is sequentially connected to a flow limiting assembly (8) and a drill bit (9), and a transmission assembly (7) for transmitting the rotational motion of the flow limiting assembly (8) is provided at the top of the frame (5); The transmission shaft (4) includes a drill rod (401) and a transmission sleeve (402) rotatably sleeved on the outer wall thereof, and the skeleton (5) includes a bottom plug disc (501), a guide tube (502), a top plug disc (503), a connecting rod (504) and a supporting platform (505), wherein the bottom plug disc (501), the top plug disc (503) and the supporting platform (505) are coaxially distributed from bottom to top, and the guide tube (502) arranged on the front and rear sides of the transmission shaft (4) is connected to the connecting rod (504). ) is fixedly penetrated through the bottom plug disc (501) and the top plug disc (503), the sampling assembly (6) comprises a sampling barrel (601), a sealing plate (602) and a drainage pipe (604), wherein the top and bottom walls of the sampling barrel (601) are movably penetrated by the connecting rod (504) and the guide pipe (502), respectively, so that the sampling barrel (601) can move upward along the guide pipe (502) and the connecting rod (504), and the top end of the inner cavity of the sampling barrel (601) is equipped with a sealing plate (602); The current limiting assembly (8) comprises a gear ring (801), planetary gears (802) and a sun gear (803), wherein the gear ring (801) is rotatably arranged above the drill bit (9), and a retaining ring on the bottom wall of the gear ring (801) is slidably connected to a retaining groove on the top wall of the drill bit (9), a sun gear (803) fixedly sleeved on the outer wall of the bottom end of the transmission sleeve (402) is provided at the center of the gear ring (801), planetary gears (802) distributed circumferentially are provided between the gear ring (801) and the sun gear (803), and the rotating sun gear (803) distributes the torque through the annular distribution. The planetary gear (802) transmits the power to the outer gear ring (801), causing the gear ring (801) to rotate around the axis until the through hole on the surface of the gear ring (801) is switched to align with the guide pipe (502) symmetrically distributed in front and back of the bottom plug disc (501). At this time, the water flow carrying soft rock in the annular drainage groove can only enter the connected guide pipe (502) through the through hole of the gear ring (801), and then be discharged from the guide pipe (502) into the liquid cavity between the top plug disc (503) and the sealing plate (602). The liquid cavity expands and the sampling operation is completed, thereby realizing the rapid switching between drilling drainage and soft rock sampling.

2. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The top end of the connecting rod (504) is fixedly connected to the supporting platform (505), and the bottom end of the connecting rod (504) is movably passed through the sampling tube (601) and the sealing plate (602) and is fixedly connected to the top plug plate (503). The supporting platform (505) is vertically slidably connected to the inner cavity of the protective shell (3), and the supporting platform (505) is rotatably sleeved in the slot of the transmission sleeve (402), so that the skeleton (5) and the sampling component (6) will sink together with the transmission shaft (4) and will not be affected by its rotation, that is, the skeleton (5) and the sampling component (6) only move up and down.

3. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: A liquid cavity with a variable volume is provided between the top plug disc (503) and the sealing plate (602) for collecting soft rock samples. A drainage pipe (604) is provided in the side wall of the sampling tube (601). The bottom end of the drainage pipe (604) passes through the bottom plug disc (501), while the top end does not exceed the top plug disc (503).

4. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The sampling assembly (6) further comprises a valve body (603), which is assembled on the top of the outer wall of the sampling tube (601). After the sampling, the soft rock sample in the liquid cavity can be emptied by opening the valve body (603).

5. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The convex ring on the surface of the drill rod (401) can be nested in the bite cavity at the top end of the transmission sleeve (402), so that the drill rod (401) can carry the transmission sleeve (402) to perform lifting movements together, and the drill rod (401) and the transmission sleeve (402) can rotate independently without interfering with each other.

6. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: A plurality of high-precision pressure sensors are evenly arranged on the inner wall of the sampling tube (601), which can measure the lateral pressure exerted on the soft rock sample in the in-situ state in real time. Displacement sensors are arranged in the sealing plate (602) and the top plug disc (503), which are used to measure the axial displacement of the soft rock sample when an axial load is applied.

7. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The transmission assembly (7) comprises a driven gear (701), a driving gear (702) and a motor (703), wherein the driven gear (701) is fixedly sleeved on the outer wall of the transmission sleeve (402), the driven gear (701) is meshed with the driving gear (702) arranged coplanar therewith, the driving gear (702) is coaxially assembled with the output shaft of the motor (703), and the base of the motor (703) is mounted on the supporting platform (505).

8. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The slot of the drill bit (9) is assembled with the drill rod (401), which is a composite structure. The front end is a carbide cutting edge for crushing soft rock, and the rear end is provided with a drainage groove and an annular drainage groove connected thereto, which can timely discharge water in the water-rich soft rock during drilling, thereby avoiding interference of water on the drilling process and subsequent sampling.

9. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The left and right side walls of the protective shell (3) are further equipped with a limiting assembly (10), wherein the limiting assembly (10) comprises a screw (1001), a shaft seat (1002) and a limiting block (1003), wherein the shaft seat (1002) is assembled on the outside of the protective shell (3), the top end of the screw (1001) is rotatably sleeved in the shaft seat (1002), and the surface of the screw (1001) is threadedly sleeved with the limiting block (1003), and by rotating the screw (1001), the moving position of the limiting block (1003) in the sliding groove of the side wall of the protective shell (3) can be adjusted to limit the lifting position of the sampling tube (601).

10. The device for sampling and in-situ testing mechanical properties of water-rich soft rock according to claim 1, characterized in that: The output shaft of the drilling rig can be assembled with the drill rod (401) through a coupling to provide output torque for the drill rod (401), so that the drill rod (401) can transmit the power output by the drilling rig to the drill bit (9) and drive it to continue to penetrate deeper, thereby realizing the drilling operation. The top of the base (1) is also equipped with a loading device. The hydraulic jack can pass through the base (1), the protective shell (3), the bearing platform (505) and the perforations on the sampling tube (601) in sequence, and apply an axial load to the soft rock sample between the sealing plate (602) and the top plug disc (503) according to the set loading rate, thereby simulating the stress state of the soft rock in actual engineering.

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