A kind of distributed armored optical cable measuring device and method based on mine drilling hole expansion hole sealing

Abstract

The application belongs to the technical field of mine surveying device drilling measurement and drilling internal distributed optical cable monitoring, in particular to a distributed armored optical cable measuring device and method based on mine drilling inflation hole sealing. The device comprises a screw rod with a disc base fixed at one end; a plurality of inflation hole sealing devices are continuously sleeved along the axial direction of the screw rod, the inflation hole sealing device comprises a pushing sleeve pipe sleeved with the screw rod, a plurality of arc-shaped expansion sheets are arranged on the outer periphery of the pushing sleeve pipe through connecting rods; an inflatable thin-walled sleeve is sleeved on the outer periphery of the inflation hole sealing device, the outer periphery of the inflatable thin-walled sleeve is provided with a spiral groove, an armored optical cable is arranged in the spiral groove, and the end of the armored optical cable close to the disc base is fixed on the spiral groove. The measuring device of the application can make the inflatable thin-walled sleeve actively expand through cooperation of the screw rod and the inflation hole sealing device, and then drive the armored optical cable to actively adhere to the inner wall of the drilling hole to realize rigid connection and active hole sealing; no hole sealing material is needed, and the coupling effect is good.

Description

Technical Field

[0001] This invention belongs to the field of mine borehole measurement and distributed optical cable monitoring technology. It relates to a device and method for deploying sensing optical cables in mine boreholes to achieve long-term monitoring of multiple geological parameters. Specifically, it is a distributed armored optical cable measurement device and method based on mine borehole expansion sealing. Background Technology

[0002] As coal seam mining depth increases, formation pressure rises, leading to a higher frequency of hazardous events such as mine tremors and rock bursts. To obtain the deformation response and energy release characteristics of deep formations during mining disturbances, it is typically necessary to drill boreholes within the coal and rock mass and install sensing elements within these boreholes to continuously monitor stress, strain, temperature, acoustic waves, and stress waves around the borehole wall. This type of borehole monitoring technology is a crucial component of mine borehole measurement and underground safety sensing, and its measurement results are of great significance for identifying the evolution of surrounding rock damage, assessing the extent of mining impacts, and predicting dynamic disasters.

[0003] In existing technologies, distributed fiber optic sensing technology has been widely used in mine borehole monitoring due to its significant advantages such as long distance, continuity, resistance to electromagnetic interference, and high spatial resolution. By drilling into the formation and then burying an armored optical cable spirally mounted on a casing into the borehole, data such as formation stress, strain, temperature, sound waves, and stress waves can be monitored, thus providing early warning information for detecting dangerous events such as mine tremors and rock bursts. Currently, when installing armored optical cables, the borehole diameter is larger than the casing, facilitating the insertion of the casing with the armored optical cable spirally mounted into the borehole. Then, cement grout or polyurethane material is manually injected to seal the gap between the casing and the borehole. Finally, curing and solidification are performed to form a rigid coupling relationship between the optical cable sensing element and the surrounding rock.

[0004] However, the above methods have the following problems: (1) The sealing material needs a certain amount of time from injection and diffusion to solidification. The long curing time leads to a long installation cycle. In addition, the sealing quality is difficult to maintain consistently throughout the entire length of the borehole due to the influence of drilling depth, borehole wall roughness, fracture development degree and downhole hot and humid environment. (2) Signal transmission relies on the sealing material to achieve coupling. However, the formation pressure in the monitoring area is generally high. The sealing material is easily squeezed by the rock mass and undergoes plastic deformation, cracking and breakage, which can easily lead to problems such as signal transmission attenuation, local measurement point distortion, poor coupling effect or even coupling failure.

[0005] To improve the installation and coupling effect of armored optical cables in boreholes, existing technologies have proposed various improvement schemes. For example, Chinese patent CN120684119A discloses a clamping and implantation device for installing multi-core optical cables in micro-drilling of formations. It achieves slow delivery of multi-core optical cables through axisymmetric clamping units, elastic balls, and pressure plates, which can reduce the risk of installation bending and borehole collapse. However, its focus is on the optical cable implantation process in micro-drilling, and it does not solve the problem of long-term stable coupling between armored optical cables and borehole walls. CN114152371A discloses an underground stress field measurement device and method based on distributed spiral armored optical cables. It lays spiral armored optical cables outside metal sleeves, but still relies on cement grout to solidify the sleeves, optical cables, and formations, which makes it difficult to avoid problems such as long curing periods and later coupling failures.

[0006] In summary, existing distributed armored optical cable measurement technology for mine boreholes still has shortcomings in terms of rapid installation, stable coupling, and maintaining adhesion after mining disturbances. Therefore, improving the coupling stability and long-term measurement reliability between the armored optical cable and the borehole wall is a pressing technical problem to be solved in the field of mine borehole measurement and underground safety monitoring. Summary of the Invention

[0007] (a) Purpose of the invention To address the shortcomings of the existing technologies, this invention aims to provide a distributed armored optical cable measurement device and method based on borehole expansion sealing in mines. By setting up an axial-push radial expansion structure within the borehole, consisting of a screw, a jacking sleeve, a connecting rod, and an arc-shaped expansion plate, the thin-walled sleeve carries the spirally laid armored optical cable to actively adhere to the borehole wall. This replaces the indirect coupling formed by traditional cement grout or polyurethane sealing materials, establishing a stable force transmission contact relationship between the armored optical cable and the borehole wall. This enables rapid installation of the measurement device, active borehole sealing, continuous sensing of multiple parameters such as stress and strain, compensation for adhesion after mining disturbances, and improved long-term measurement reliability.

[0008] (II) Technical Solution To achieve the objective of this invention and solve its technical problems, the present invention adopts the following technical solution: In a first aspect, the present invention proposes a distributed armored optical cable measurement device based on mine borehole expansion sealing, comprising a screw, multiple expansion sealing assemblies, an expandable thin-walled sleeve, and an armored optical cable, wherein: The screw is arranged axially inside the mine borehole. The outer wall of the screw is provided with a transmission thread, a disc base is fixedly installed at its bottom end, and a nut adjustment component that mates with the transmission thread is provided at its top end. The plurality of expansion sealing assemblies are sequentially sleeved on the outer periphery of the screw along the axial direction. Each expansion sealing assembly includes at least a push sleeve sleeved on the screw, a plurality of arc-shaped expansion plates disposed on the outer periphery of the push sleeve, and a plurality of connecting rods movably connected between the push sleeve and the arc-shaped expansion plates. Under the axial push action of the nut adjusting component, the push sleeve moves along the screw axial direction toward the disc base, and drives the arc-shaped expansion plates to change from a closed state to a radially outward expansion state through the connecting rods. In the closed state, the plurality of arc-shaped expansion plates form a ring-shaped support structure. Under the constraint of the connecting rods, each arc-shaped expansion plate generates axial and radial movement relative to the push sleeve without generating circumferential relative rotation. The expandable thin-walled sleeve is fitted around the outer periphery of multiple expansion sealing components. Its outer periphery has a spiral groove extending spirally along the axial direction. Its bottom contacts the disc base and expands radially synchronously with the arc-shaped expansion plate when the arc-shaped expansion plate changes from a closed state to a radially outward expansion state. The armored optical cable is arranged along the spiral groove on the outer periphery of the expandable thin-walled sleeve, and moves radially outward when the thin-walled sleeve expands and finally presses against the borehole wall of the mine, forming a distributed measurement coupling structure for the transmission of stress and strain of the borehole wall.

[0009] Secondly, the present invention also provides a method for implementing the above-mentioned distributed armored optical cable measurement device based on mine borehole expansion sealing, comprising at least the following steps: SS1. Device pre-assembly: Multiple expansion sealing components are sequentially fitted onto the outer periphery of the screw along the axial direction, so that the arc-shaped expansion plates in each expansion sealing component are in a closed state, and an expandable thin-walled sleeve is fitted onto the outer periphery of multiple expansion sealing components, and the armored optical cable is laid along the spiral groove of the expandable thin-walled sleeve. SS2. Drilling and Equipment Deployment: Drill a borehole in the mine and install the assembled measuring device axially into the borehole, ensuring that the disc base at the bottom end of the screw reaches the bottom of the borehole, and that the expandable thin-walled sleeve and armored optical cable remain in an unexpanded deployment state. SS3. Axial jacking and radial expansion: Rotate the nut adjustment piece at the top end of the screw to make it rotate along the transmission thread toward the bottom of the mine borehole, and apply axial jacking action to the jacking sleeve in each expansion sealing assembly. Under the axial jacking action, the jacking sleeve overcomes the sliding resistance between itself and the screw thread and moves toward the disc base. The connecting rod rotates with the movement of the jacking sleeve and drives each arc-shaped expansion plate to change from a closed state to a radially outward expansion state. SS4. Expansion sealing and wall coupling: Through the radial expansion of the expandable thin-walled sleeve, the armored optical cable laid along the spiral groove moves radially outward and continuously approaches the inner wall of the borehole until the armored optical cable is completely pressed against the inner wall of the borehole to form a distributed measurement coupling structure. The expandable thin-walled sleeve and the borehole wall of the mine form a sealing fit. SS5. Distributed Measurement: Connect the armored optical cable to a distributed optical fiber demodulation device to obtain the optical signal change information corresponding to the spiral layout path of the armored optical cable, and based on this, perform distributed measurement of the strain, deformation or stress response of the borehole wall in the axial and / or circumferential range. SS6. Disturbance Compensation Maintenance: When mining activities affect the environment, the borehole wall undergoes local deformation, or the armored optical cable's fit deteriorates, continue to rotate the adjusting nut to further expand the arc-shaped expansion plate radially outward and drive the expandable thin-walled sleeve to compensate for the expansion. This allows the expansion device to continue expanding to adapt to changes in the formation, thereby maintaining the fit measurement status between the armored optical cable and the mine borehole wall.

[0010] (III) Technical Effects Compared with the prior art, the distributed armored optical cable measurement device and method based on mine borehole expansion sealing of the present invention has the following beneficial and significant technical effects: (1) The distributed armored optical cable measuring device of the present invention can make the thin-walled sleeve actively expand through the cooperation between the screw and the expansion sealing component, thereby driving the armored optical cable to actively adhere to the inner wall of the borehole and realize active sealing. Since no sealing material is required, the problem of poor coupling effect and coupling failure caused by deformation, cracking and breakage of sealing material can be reduced. It can also reduce construction links, shorten the installation cycle of borehole monitoring device, and improve the ability to quickly deploy downhole.

[0011] (2) The measuring device of the present invention sets a spiral groove on the outer periphery of the expandable thin-walled sleeve and lays the armored optical cable along the spiral groove. After the thin-walled sleeve expands, the armored optical cable will directly adhere to the inner wall of the borehole, forming a direct coupling structure that transmits the deformation of the borehole wall to the optical cable. That is, the armored optical cable is in rigid contact with the inner wall of the borehole, and the monitoring data such as stress and strain are directly transmitted to the armored optical cable without intermediate medium loss. This avoids the signal attenuation, local measurement point distortion and coupling failure caused by compression deformation, interface debonding, cracking and breakage when using sealing materials as intermediate medium.

[0012] (3) The present invention arranges multiple expansion sealing components continuously along the screw axis, so that the arc-shaped expansion plate can form segmented support and continuous outward expansion in the drilling depth direction, thereby enabling the expandable thin-walled sleeve and armored optical cable to remain attached to the wall in a longer measurement section, which is beneficial to improving the continuity and reliability of multi-parameter monitoring data such as stress, strain, temperature, sound waves and stress waves in mine boreholes.

[0013] (4) The measuring device of the present invention has strong adaptability. After the measuring device expands, if the coupling is not accurate due to subsequent mining or other factors, the expansion sealing component can continue to expand to adapt to the changes in the strata. Even if the borehole collapses locally, the expansion component can continue to expand to keep the armored optical cable attached to the inner wall of the borehole, which improves the device's adaptability to complex mining conditions such as high ground pressure, strong mining and local collapse. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of the distributed armored optical cable measurement device of the present invention.

[0016] Figure 2 This is a schematic diagram of the axial cross-section of the distributed armored optical cable measuring device of the present invention.

[0017] Figure 3 This is a schematic diagram of the radial cross-section of the distributed armored optical cable measuring device of the present invention before expansion.

[0018] Figure 4 This is a schematic diagram of the radial cross-section of the distributed armored optical cable measuring device of the present invention after expansion.

[0019] Figure 5 This is a schematic diagram of the hinge structure in the distributed armored optical cable measurement device of the present invention.

[0020] Figure 6 This is a schematic diagram of the straightener structure in the distributed armored optical cable measurement device of the present invention.

[0021] Figure 7 This is a schematic diagram of the thin-walled sleeve structure in the distributed armored optical cable measurement device of the present invention.

[0022] Figure 8 This is a schematic diagram of the screw structure in the distributed armored optical cable measurement device of the present invention.

[0023] Figure 9 This is a flowchart illustrating the implementation method of the distributed armored optical cable measurement device of the present invention.

[0024] In the diagram: 11-Screw; 12-Disc base; 21-Expandable thin-walled sleeve; 22-Helical groove; 23-Armored optical cable; 31-Adjusting nut; 32-Washer; 33-Push ring; 34-Center; 35-Through hole; 41-Arc-shaped expansion plate; 42-Push sleeve; 43-Connecting rod; 44-First hinge seat; 45-Second hinge seat; 46-Pin. Detailed Implementation

[0025] This invention aims to provide a distributed armored optical cable measurement device and method based on mine borehole expansion sealing. To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. The described embodiments are some, but not all, embodiments of this invention, and are exemplary, intended to explain the invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] It should be noted that the distributed armored optical cable measurement device and method based on mine borehole expansion sealing described in this invention focuses on achieving distributed measurement coupling within the borehole through the axial pushing of the screw, the radial expansion of the expansion sealing assembly, the synchronous deformation of the expandable thin-walled sleeve, and the structural coordination between the armored optical cable and the borehole wall. The screw, disc base, pushing sleeve, arc-shaped expansion plate, connecting rod, expandable thin-walled sleeve, and armored optical cable components mentioned in this specification can be adapted and adjusted in shape, size, material, and quantity according to the borehole diameter, depth, surrounding rock strength, mining disturbance degree, and measurement accuracy requirements. As long as the armored optical cable can be pressed against the borehole wall along with the expandable thin-walled sleeve and maintain the measurement coupling state, it falls within the implementation embodiments of the technical concept of this invention.

[0027] Example 1: Distributed Armored Optical Cable Measurement Device like Figures 1 to 8 As shown, the distributed armored optical cable measurement device based on mine borehole expansion sealing proposed in this invention is used to deploy distributed armored optical cables along the axial direction of the mine borehole and form a stable coupling between the armored optical cables and the borehole wall through expansion sealing. By utilizing the controllable expansion sealing effect, a continuous, reliable, and compensable adjustable mechanical coupling relationship is established between the armored optical cables and the borehole wall, thereby improving the distributed sensing accuracy and long-term service stability of borehole wall strain, deformation, and / or stress response. The device generally includes a screw 11, multiple expansion sealing components, an expandable thin-walled sleeve 21, an armored optical cable 23, and a nut adjustment component, a washer 32, and a booster ring 33 disposed on the upper end of the screw 11. In deep hole or long hole applications, multiple centralizers 34 can also be arranged at intervals along the axial direction. Wherein: The screw 11 is axially arranged within the mine borehole. An external thread is provided on the outer circumference of the screw 11 as a transmission thread. A circular base 12, coaxially arranged with the screw 11, is fixedly mounted at its bottom end. The outer diameter of the circular base 12 matches the borehole diameter. A nut adjustment component, engaging with the transmission thread, is provided at the top end of the screw 11. In this embodiment, the nut adjustment component is specifically an adjusting nut 31, which can be screwed along the transmission thread of the screw 11 to apply an axial pushing force towards the circular base 12 to multiple expansion sealing assemblies. The circular base 12 serves as an end positioning reference when the device is lowered to the bottom of the borehole and acts as a reaction force bearing component when the expansion sealing assemblies are subjected to axial pushing, ensuring that the axial pushing force is stably converted into the radial opening force of the arc-shaped expansion plate 41.

[0028] Multiple expansion sealing assemblies are continuously sleeved around the outer periphery of the screw 11 along its axial direction. Each expansion sealing assembly includes a pusher sleeve 42 sleeved with the screw 11. The pusher sleeve 42 can be relatively fixed on the screw 11 and can move along the axial direction of the screw 11 after overcoming relative sliding resistance. To prevent the pusher sleeve 42 from moving prematurely during device transportation, assembly, and lowering, a controllable damping fit structure can be provided between the pusher sleeve 42 and the screw 11. The controllable damping fit structure is used to maintain the initial position stability of the pusher sleeve 42 during the device lowering stage and allows the pusher sleeve 42 to undergo axial displacement along the screw 11 after the axial thrust applied by the adjusting nut 31 reaches a set action level. The controllable damping fit structure can adopt at least one of the following: threaded interference fit, elastic clamping element, friction bushing, or surface roughened friction pair, to improve the consistency of action when multiple expansion sealing assemblies start expansion.

[0029] Multiple identical arc-shaped expansion plates 41 are evenly arranged around the outer periphery of the jacking sleeve 42. In the closed state, these arc-shaped expansion plates 41 form a ring-shaped support structure coaxial with the jacking sleeve 42. Each arc-shaped expansion plate 41 is evenly distributed circumferentially along the jacking sleeve 42 and has the same arc-shaped profile and axial extension length, enabling the expandable thin-walled sleeve 21 to achieve a relatively balanced circumferential outward expansion effect when supported. The outer radius of the arc-shaped expansion plates 41 in both the closed and radially outward expansion states is smaller than the radius of the disc base 12, ensuring that each expansion sealing assembly does not exceed the outer contour of the disc base during device lowering, initial positioning, and subsequent expansion, thereby reducing the risk of jamming during device lowering.

[0030] Each arc-shaped expansion plate 41 is connected to the push sleeve 42 via a connecting rod 43. One end of the connecting rod 43 is hinged to the inner wall of the arc-shaped expansion plate 41 around the center via a first hinge seat 44, and the other end is hinged to the outer wall of the push sleeve 42 via a second hinge seat 45. The hinged connection means that the arc-shaped expansion plate 41 can only move axially and radially relative to the push sleeve 42, but does not rotate circumferentially. The first hinge seat 44 at both ends of the same connecting rod 43 is closer to the disc base 12 than the second hinge seat 45. When the adjusting nut 31 pushes the push sleeve 42 toward the disc base 12 via the washer 32 and the push ring 33, the connecting rod 43 rotates under geometric constraints and converts the axial displacement of the push sleeve 42 into the radial outward displacement of the arc-shaped expansion plate 41.

[0031] like Figure 5 As shown, the specific hinge connection method between the connecting rod 43, the arc-shaped expansion plate 41, and the push sleeve 42 can be selected as follows: the end of the connecting rod 43 is set as a U-shaped fork structure, and the first hinge seat 44 and the second hinge seat 45 are respectively provided with connecting plates that can be inserted into the U-shaped fork of the connecting rod 43. The hinge connection is achieved by the pin 46 passing through the connecting plate and the U-shaped fork of the connecting rod 43. The axial direction of the pin 46 makes the rotation plane of the connecting rod 43 lie in the plane containing the axial and radial directions of the screw 11, thereby limiting the circumferential deflection of the arc-shaped expansion plate 41 relative to the push sleeve 42; multiple connecting rods 43 are circumferentially spaced and evenly distributed around the push sleeve 42, so that each arc-shaped expansion plate 41 obtains consistent rotational support and force transmission path when the push sleeve 42 is pushed by force.

[0032] Among them, in the first expansion sealing assembly adjacent to the disc base 12, such as Figure 2 As shown, the axial length of the push sleeve 42 is less than the axial length of the arc-shaped expansion plate 41, and when the arc-shaped expansion plate 41 is in the closed state, its axial end face away from the disc base 12 is aligned with the axial end face of the push sleeve 42 away from the disc base 12. The axial length of the push sleeve 42 of the other expansion sealing assemblies is equal to the axial length of the arc-shaped expansion plate 41, and when the arc-shaped expansion plate 41 is in the closed state, both its axial end faces are aligned with the two axial end faces of the push sleeve 42. Furthermore, the radius of the arc-shaped expansion plate 41 before and after expansion is less than the radius of the disc base 12, and the connecting rods 43 are spaced apart and evenly distributed along the circumference of the push sleeve 42. This structure enables the first expansion sealing assembly near the disc base 12 to form a stable end limit with the disc base 12, and the remaining expansion sealing assemblies to form a continuously distributed expansion support section along the drilling axis.

[0033] An expandable thin-walled sleeve 21 is fitted around the outer periphery of the expansion sealing assembly. The inner diameter of the expandable thin-walled sleeve 21 is the same as the outer diameter of the arc-shaped expansion plate 41 of the expansion sealing assembly in the closed state. The inner diameter of the expandable thin-walled sleeve 21 before expansion is smaller than the outer diameter of the disc base 12, and the maximum outer diameter of the expandable thin-walled sleeve 21 after expansion is not smaller than the outer diameter of the disc base 12. The length of the expandable thin-walled sleeve 21 is consistent with the total length of the arc-shaped expansion plates 41 of all expansion sealing devices. Thus, the expandable thin-walled sleeve 21 is easy to be lowered into the mine borehole with the device in the unexpanded state, and can expand radially outward synchronously with the expansion plate 41 and gradually approach the borehole wall in the expanded state, thereby forming a continuous wall-adhering section distributed along the borehole axis.

[0034] Preferably, the outer surface of the arc-shaped expansion plate 41 can be configured as a low-wear guide surface or arc-shaped support surface that mates with the inner surface of the expandable thin-walled sleeve 21. A circumferential gap compensation area is reserved between adjacent arc-shaped expansion plates 41, so that when the arc-shaped expansion plate 41 transitions from a closed state to a radially outward expansion state, it can smoothly support the expandable thin-walled sleeve 21, and the circumferential gap can release the effects of local assembly errors and in-hole eccentric loads. The expandable thin-walled sleeve 21 can be made of a thin-walled metal material with radial elastic-plastic deformation capability, fiber-reinforced composite material, or metal and polymer composite laminate material, and can be configured as an axially continuous equal thickness structure, or as a variable thickness structure with a thinner middle and thicker ends, to balance radial expansion response capability and long-term circumferential support stiffness.

[0035] The expandable thin-walled sleeve 21 has a spiral groove 22 spirally arranged along its outer periphery. An armored optical cable 23 is housed within the spiral groove 22, with one end of the armored optical cable 23 near the disc base 12 fixed to the spiral groove 22. A portion of the armored optical cable 23 is located within the spiral groove 22 radially, while another portion extends beyond it. Specifically, the spiral groove 22 extends spirally along the axial direction of the expandable thin-walled sleeve 21. The width of the spiral groove 22 matches the outer diameter of the armored optical cable 23, and the depth of the spiral groove 22 is less than the outer diameter of the armored optical cable 23. This allows the inner radial portion of the armored optical cable 23 to be contained and restrained by the spiral groove 22, while the outer radial portion forms a radially exposed portion protruding from the outer periphery of the expandable thin-walled sleeve 21. When the expandable thin-walled sleeve 21 expands radially outward, the radially exposed portion of the armored optical cable 23 first presses against the borehole wall and forms a continuously distributed wall-attached measurement section along the spiral extension direction of the spiral groove 22.

[0036] One end of the armored optical cable 23 near the disc base 12 can be fixed in the spiral groove 22 by a fixing plate, crimping ring, or embedded groove section, while the other end near the adjusting nut 31 remains axially slidable relative to the spiral groove 22. Thus, during the radial expansion of the expandable thin-walled sleeve 21, the armored optical cable 23 can slide in a controlled manner along the spiral groove 22 to adapt to changes in its outer circumference length, while also being confined within a predetermined groove by the spiral groove 22, reducing the risk of the armored optical cable 23 coming off the groove, twisting, localized arching, or being subjected to additional tensile damage.

[0037] A push ring 33, a washer 32, and an adjusting nut 31 are sequentially fitted onto the screw 11. The push ring 33 and the washer 32 are slidably fitted onto the screw 11, and the adjusting nut 31 is threadedly connected to the screw 11. The outer diameter of the push ring 33 is equal to the outer diameter of the push sleeve 42. During the screwing process, the adjusting nut 31 transmits the axial pushing force evenly to the outermost push sleeve 42 through the washer 32 and the push ring 33, thereby reducing the local off-center load, end face wear, and force imbalance that may occur when the adjusting nut 31 acts directly on the push sleeve 42.

[0038] In some embodiments, an anti-reverse retention structure may be provided between the adjusting nut 31 and the screw 11. This anti-reverse retention structure is used to maintain the predetermined axial position of the adjusting nut 31 relative to the screw 11 after one or more expansion adjustments. The anti-reverse retention structure may employ at least one of the following: a locking nut, a backlash washer, a ratchet check valve, a radial locking element, or a friction self-locking thread, to reduce the impact of mine vibration, mining impact, or long-term load fluctuations on the position of the adjusting nut 31 and prevent the established expansion preload from retracting.

[0039] As a preferred embodiment, when the measuring device is used for deep or long boreholes, a stabilizer 34 is provided along the outer circumference of the screw 11 at intervals of several expansion sealing devices. The stabilizer 34 is a plate-shaped ring structure. The outer diameter of the stabilizer 34 is the same as the outer diameter of the disc base 12, and the inner diameter of the stabilizer 34 is adapted to the outer diameter of the adjacent jacking sleeve 42. The stabilizer 34 is provided with a through hole 35 for the armored optical cable 23 to pass through. The stabilizer 34 can maintain the axial concentricity between the measuring device and the mine borehole during the lowering process, reducing the skew friction between the device and the borehole wall.

[0040] Specifically, the stabilizer 34 is sleeved on an adjacent pusher sleeve 42. The axial length of the pusher sleeve 42 is greater than the axial length of the arc-shaped expansion plate 41 of the expansion sealing device. When the arc-shaped expansion plate 41 is in the closed state, the end face of the pusher sleeve 42 that is axially away from the stabilizer 34 is aligned with the end face of the pusher sleeve 42 that is axially away from the stabilizer 34. The other end of the pusher sleeve 42 extends beyond the arc-shaped expansion plate 41 by an axial length equal to the thickness of the stabilizer 34. The stabilizer 34 is also provided with a through hole 35 for the armored optical cable 23 to pass through. The stabilizer 34 divides the expandable thin-walled sleeve 21 into multiple segments. Adjacent axial sleeve segments can expand radially outward with the corresponding expansion sealing components, thereby adapting to local differences in the borehole diameter.

[0041] With the above structure, the measuring device in this embodiment can keep the arc-shaped expansion plate 41 in a closed state during the lowering stage, and achieve in-hole guidance and positioning with the disc base 12 and the centralizer 34. After installation, the adjusting nut 31 is screwed in to drive the jacking sleeve 42 to move axially, and then the connecting rod 43 drives the arc-shaped expansion plate 41 to expand radially outward, so that the expandable thin-walled sleeve 21 carrying the armored optical cable 23 is gradually pressed against the borehole wall, thereby forming a distributed measurement coupling structure for the transfer of stress and strain of the borehole wall. This structure can reduce the dependence on cement slurry or polyurethane sealing materials, and can also compensate for expansion by continuing to screw in the adjusting nut 31 when there is subsequent mining disturbance, local deformation of the borehole wall, or a decrease in the fit, thus maintaining the fit measurement state between the armored optical cable 23 and the borehole wall.

[0042] Example 2: Implementation method of distributed armored optical cable measurement device Based on Embodiment 1 above, Embodiment 2 further provides an implementation method for the above-mentioned distributed armored optical cable measurement device, used to implement the distributed armored optical cable measurement device based on mine borehole expansion sealing in Embodiment 1, such as... Figure 9 As shown, the method specifically includes the following steps during implementation: SS1. Device Pre-assembly: Based on the borehole diameter, depth, borehole axis inclination, borehole wall integrity, expected monitoring section length, and distributed optical fiber demodulation accuracy requirements of the target mine borehole, the structural parameters and quantities of the screw 11, disc base 12, multiple expansion sealing assemblies, expandable thin-walled sleeve 21, armored optical cable 23, booster ring 33, gasket 32, adjusting nut 31, and centralizer 34 are determined.

[0043] Multiple expansion sealing assemblies are sequentially fitted onto the outer periphery of the screw 11 along the axial direction, ensuring that the arc-shaped expansion plates 41 in each expansion sealing assembly are in a closed state, forming a ring-shaped support structure. An expandable thin-walled sleeve 21 is fitted onto the outer periphery of the multiple expansion sealing assemblies, with the inner wall of the expandable thin-walled sleeve 21 engaging with the outer edge of the closed arc-shaped expansion plates 41. The armored optical cable 23 is continuously laid along the spiral groove 22 on the outer periphery of the expandable thin-walled sleeve 21, with one end of the armored optical cable 23 near the disc base 12 fixed within the spiral groove 22, while the other end remains relatively slidable. This pre-assembly method ensures that the measuring device maintains a small outer diameter before lowering and that the armored optical cable 23 is pre-positioned in a stable arrangement limited by the spiral groove 22.

[0044] SS2. Drilling and Equipment Lowering Drilling is carried out within the coal and rock mass at predetermined monitoring locations. The assembled measuring device is then installed into the borehole along its axial direction. At this point, the arc-shaped expansion plate 41 is fully closed, while the expandable thin-walled sleeve 21 and armored optical cable 23 are in an unexpanded state. When the disc base 12 reaches the bottom of the borehole, the measuring device is in place. During the lowering process, the disc base 12 serves as an outer diameter reference and borehole bottom positioning component, while the centralizer 34 acts as a centering guide in deep or long borehole conditions to reduce the device's tendency to deviate, become stuck, or experience strong local friction with the borehole wall within the borehole.

[0045] SS3. Axial jacking and radial expansion: Rotating the adjusting nut 31 causes it to advance along the drive thread on the outer wall of the screw 11 towards the bottom of the mine borehole. This, along with the shim 32 and the pusher ring 33, applies an axial pushing force to the outermost pusher sleeve 42. The pusher ring 33 drives the pusher sleeve 42 to overcome the sliding resistance between its thread and the screw 11, thus pushing the pusher sleeve 42 towards the disc base 12. During this process, the number of rotations, the advancing displacement, or the axial position change relative to the exposed end of the screw 11 of the adjusting nut 31 are recorded simultaneously. This information serves as the basis for controlling the axial advance of the pusher sleeve 42 and the radial expansion of the arc-shaped expansion plate 41. Since the arc-shaped expansion plate 41 cannot rotate circumferentially relative to the screw 11, it cannot move axially due to the obstruction of the disc base 12 and can only move radially under the rotation of the connecting rod 43.

[0046] SS4. Expansion sealing and wall coupling After the arc-shaped expansion plate 41 moves radially, it expands, which in turn drives the thin-walled sleeve 21 to expand radially outward and continuously approach the inner wall of the borehole. When the expandable thin-walled sleeve 21 expands, it drives the armored optical cable 23, which is laid along the spiral groove 22, to move radially outward, and the radially exposed part of the armored optical cable 23 gradually presses against the borehole wall until the armored optical cable 23 is completely pressed against the inner wall of the borehole. During the wall-adhesion coupling process, the adjustment nut 31 can be rotated in stages for control. After each rotation, the adjustment is paused and the change in the measurement response of the armored optical cable 23 is observed. When the output signal of the armored optical cable 23 changes from a discontinuous fluctuation state to a continuous and stable response state, and the abnormal abrupt changes in adjacent measurement sections decrease, it is determined that a wall-adhesion coupling state suitable for the transmission of stress and strain of the borehole wall has been formed between the armored optical cable 23 and the borehole wall. Furthermore, during the expansion of the expandable thin-walled sleeve 21, since one end of the armored optical cable 23 near the disc base 12 is fixed to the spiral groove 22 while the other end is relatively free, it can slide along the spiral groove 22 to adapt to the expansion process of the expandable thin-walled sleeve 21, reducing the risk of the armored optical cable 23 being damaged by excessive stretching, torsion, or local compression. Finally, the screw 11 is fixed at the exposed part of the drill hole, and the anti-reverse retaining structure maintains the predetermined axial position of the adjusting nut 31 to maintain the expansion preload state.

[0047] SS5. Distributed Measurement After wall-mounted coupling is completed, the end of the armored optical cable 23 located outside the borehole opening is connected to a distributed fiber optic demodulation device for initial signal acquisition. This acquires initial strain reference data, initial temperature reference data, or initial vibration response data of the armored optical cable 23 distributed along the borehole axis. During subsequent monitoring, the distributed fiber optic demodulation device continuously acquires optical signal change information corresponding to the spiral layout path of the armored optical cable 23 and converts this optical signal change information into strain, deformation, temperature, or vibration response information of the borehole wall at different depths. Since the armored optical cable 23 is pressed against the borehole wall along with the expandable thin-walled sleeve 21, the deformation response of the borehole wall can be directly sensed through the armored optical cable 23, thereby improving the continuity and reliability of the distributed measurement data.

[0048] SS6. Disturbance Compensation Preservation If subsequent mining activities, local deformation of the borehole wall, local spalling, or a decrease in the fit of the armored optical cable 23 lead to inaccurate coupling, the expansion device can continue to expand to adapt to changes in the formation. The fit between the armored optical cable 23 and the borehole wall is determined based on the continuity of the measurement signal along the borehole axis, the degree of abrupt changes in response of adjacent measurement sections, and the stability of repeatedly acquired signals in the same section. When there is signal attenuation, intermittent response, increased dispersion of repeatedly acquired signals, or a continuously increasing deviation from the initial reference data in a local section, it is determined that the fit in the corresponding section may have decreased. In this case, the adjusting nut 31 is rotated further to move the jacking sleeve 42 further towards the disc base 12, and the connecting rod 43 drives the arc-shaped expansion plate 41 to expand radially outward, allowing the expandable thin-walled sleeve 21 to compensate for the expansion, thereby maintaining the fit measurement state between the armored optical cable 23 and the borehole wall. After each compensation expansion, distributed measurement data before and after compensation are collected and compared. When the signal continuity improves, local abnormal fluctuations decrease, and repeated acquisition results tend to stabilize, it is confirmed that the compensation expansion has met the requirements for maintaining the wall-attached measurement state. This ensures that even if the borehole partially collapses, the expansion device can continue to expand to keep the armored optical cable 23 attached to the borehole wall.

[0049] Through the above steps, this embodiment enables the pre-assembly and lowering of the measuring device within the mine borehole, axial jacking, radial expansion, expansion sealing, wall-attached coupling, distributed measurement, and disturbance compensation maintenance. Compared to installation methods that rely on cement grout or polyurethane material curing coupling, this embodiment uses mechanical expansion to directly press the armored optical cable against the borehole wall, reducing the adverse effects of deformation, cracking, or breakage of the sealing material on signal transmission. Furthermore, it allows for compensation of the fit after mining disturbances by re-screwing the adjusting nut, thereby improving the reliability of long-term mine borehole monitoring and its adaptability to complex operating conditions.

[0050] The objectives of this invention have been fully and effectively achieved through the above embodiments. Those skilled in the art will understand that this invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments described above. Although the invention has been described with reference to what is currently considered the most practical and preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments, and any modifications that do not depart from the functional and structural principles of the invention will be included within the scope of the claims.

Claims

1. A distributed armored optical cable measurement device based on mine borehole expansion sealing, characterized in that, include: The screw is arranged axially inside the mine borehole. The outer wall of the screw is provided with a transmission thread, a disc base is fixed at the bottom end, and a nut adjustment component that mates with the transmission thread is provided at the top end. Multiple expansion sealing assemblies are sequentially sleeved around the outer periphery of the screw along the axial direction. Each expansion sealing assembly includes at least a push sleeve connected to the screw, multiple arc-shaped expansion plates disposed around the push sleeve, and multiple connecting rods movably connected between the push sleeve and the arc-shaped expansion plates. The push sleeve moves towards the disc base under the axial push action of the nut adjusting component, and drives each arc-shaped expansion plate to change from a closed state to a radially outward expansion state through the connecting rods. In the closed state, the multiple arc-shaped expansion plates form a ring-shaped support structure. Each arc-shaped expansion plate generates axial and radial movement relative to the push sleeve under the constraint of the connecting rods without generating circumferential relative rotation. An expandable thin-walled sleeve is fitted around the outer periphery of multiple expansion sealing assemblies. Its outer periphery has a spiral groove extending axially. The bottom contacts the disc base, and it expands radially outward synchronously when the arc-shaped expansion plates transition from a closed state to a radially outward expanding state. The inner diameter of the expandable thin-walled sleeve in its unexpanded state matches the outer diameter of the annular support structure formed by the multiple arc-shaped expansion plates in their closed state. Its outer diameter before expansion is smaller than the outer diameter of the disc base, and its maximum outer diameter after expansion is not smaller than the outer diameter of the disc base. Furthermore, the total axial length of the expandable thin-walled sleeve is consistent with the total axial length of all the arc-shaped expansion plates in the multiple expansion sealing assemblies. The armored optical cable is laid along a spiral groove on the outer circumference of an expandable thin-walled sleeve. As the expandable thin-walled sleeve expands, it moves radially outward and eventually presses against the borehole wall of the mine. The armored optical cable is continuously laid along the spiral groove and partially embedded and limited within the spiral groove. The groove depth is less than the outer diameter of the armored optical cable, and the groove width matches the outer diameter of the armored optical cable. The radially inner part of the armored optical cable is accommodated within the spiral groove, while the radially outer part forms a radially exposed portion protruding from the outer circumference of the expandable thin-walled sleeve. After the expandable thin-walled sleeve expands radially outward, the radially exposed portion of the armored optical cable first presses against the borehole wall of the mine and gradually forms a continuous wall-fitting contact state, forming a continuously distributed wall-fitting measurement section along the extension direction of the spiral groove. The end of the armored optical cable near the disc base is fixed in the spiral groove by a fixing plate, a crimping ring, or an embedded groove section, while the end near the nut adjustment component remains axially slidable relative to the spiral groove.

2. The apparatus according to claim 1, characterized in that, The disc base is coaxially and fixedly connected to the screw. Its outer diameter is adapted to the diameter of the target mine borehole. When the device is lowered to the bottom of the mine borehole, it forms an end positioning reference in the axial direction and a guide limit in the radial direction. The disc base is formed as a reaction force bearing component when multiple expansion sealing components undergo radial expansion. The jacking sleeve located above it is driven by the nut adjustment component and pushed towards the disc base. Under the axial blocking action of the disc base, the axial pushing force is converted into the radial opening force of the arc-shaped expansion plate.

3. The apparatus according to claim 1, characterized in that, Multiple arc-shaped expansion plates in each expansion sealing assembly are evenly distributed along the circumference of the push sleeve, and each arc-shaped expansion plate has the same arc-shaped profile and axial extension length. In the closed state, the multiple arc-shaped expansion plates form a ring-shaped support structure coaxial with the push sleeve. The outer radius of each arc-shaped expansion plate in the closed and radially outward expansion states is smaller than the radius of the disc base. Each expansion sealing assembly does not exceed the outer contour range of the disc base during device lowering, initial positioning, and subsequent expansion.

4. The apparatus according to claim 1, characterized in that, One end of each link is connected to the inner wall of the corresponding arc-shaped expansion plate through the first hinge seat, and the other end is connected to the outer wall of the push sleeve through the second hinge seat. The first hinge seat on the same link is arranged closer to the disk base than the second hinge seat. When the push sleeve moves towards the disk base, each link converts the axial displacement of the push sleeve into the radial outward displacement of the arc-shaped expansion plate under the action of geometric constraints.

5. The apparatus according to claim 4, characterized in that, Each link has a U-shaped fork structure at both ends. The first and second hinge seats are respectively provided with connecting pieces that can be inserted into the corresponding U-shaped forks. The connecting pieces and U-shaped forks are connected by a pin. The rotation plane is arranged along the plane of the screw axis and radial direction, and is formed to restrict the circumferential deflection of the arc-shaped expansion plate relative to the push sleeve. Multiple links are circumferentially spaced and evenly distributed around the push sleeve.

6. The apparatus according to claim 1, characterized in that, In the first expansion sealing assembly adjacent to the disc base, the axial length of the push sleeve is less than the axial length of the arc-shaped expansion piece of the assembly, and when the arc-shaped expansion piece is in the closed state, its end face away from the disc base in the axial direction is aligned with the end face of the push sleeve away from the disc base in the axial direction; in the remaining expansion sealing assemblies, the axial length of the push sleeve is equal to the axial length of the arc-shaped expansion piece, and when the arc-shaped expansion piece is in the closed state, its two end faces in the axial direction are aligned with the two end faces of the push sleeve in the axial direction.

7. The apparatus according to claim 1, characterized in that, A booster ring and a washer are sequentially arranged along the screw axis between the nut adjusting component and the outermost jacking sleeve closest to the mine borehole opening. Both the booster ring and the washer are sleeved on the outer circumference of the screw and slide in fit with the screw. The outer diameter of the booster ring is adapted to the outer diameter of the jacking sleeve. During the rotation and advancement process, the nut adjusting component transmits the axial jacking force to the jacking sleeve through the washer and the booster ring.

8. The apparatus according to claim 1, characterized in that, Multiple stabilizers are also provided on the outer periphery of the screw. Each stabilizer is arranged at intervals along the axial direction of the screw and located between adjacent expansion sealing assemblies. The stabilizer is a plate-shaped ring structure. Its outer diameter is adapted to the outer diameter of the disc base, and its inner diameter is adapted to the outer diameter of the adjacent push sleeve. It is provided with a through hole for the armored optical cable to pass through. Each stabilizer is sleeved on an adjacent push sleeve. The axial length of the push sleeve is greater than the axial length of the arc-shaped expansion piece in the expansion sealing assembly. When the arc-shaped expansion piece is in the closed state, the end face of the push sleeve that is axially away from the stabilizer is aligned with the end face of the corresponding arc-shaped expansion piece that is axially away from the stabilizer. The other end of the push sleeve extends beyond the arc-shaped expansion piece by an axial length equal to the thickness of the stabilizer.

9. A method for implementing the apparatus according to any one of claims 1 to 8, characterized in that, It should include at least the following steps: SS1. Multiple expansion sealing assemblies are sequentially fitted onto the outer periphery of the screw along the axial direction, so that the arc-shaped expansion plates in each expansion sealing assembly are in a closed state, and an expandable thin-walled sleeve is fitted onto the outer periphery of the multiple expansion sealing assemblies, and the armored optical cable is laid along the spiral groove of the expandable thin-walled sleeve. SS2. During the construction of the mine borehole, the assembled measuring device is installed axially into the mine borehole, so that the disc base at the bottom end of the screw reaches the bottom of the mine borehole, and the expandable thin-walled sleeve and the armored optical cable are kept in an unexpanded state. SS3. Rotate the nut adjustment piece at the top end of the screw so that it rotates along the transmission thread toward the bottom of the mine borehole and applies an axial pushing force to the jacking sleeve in each expansion sealing assembly. The connecting rod rotates with the jacking sleeve and drives each arc-shaped expansion plate to change from a closed state to a radially outward expansion state. SS4. Through the radial expansion of the expandable thin-walled sleeve, the armored optical cable, which is laid along the spiral groove, moves radially outward and continuously approaches the inner wall of the borehole until the armored optical cable is completely pressed against the inner wall of the borehole to form a distributed measurement coupling structure. A sealing fit is formed between the expandable thin-walled sleeve and the borehole wall. The wall-attaching coupling process is controlled by rotating the nut adjustment component in stages. After each rotation, the process is paused and the measurement response of the armored optical cable is acquired. When the output signal of the armored optical cable changes from a discontinuous fluctuation state to a continuous and stable response state, and the abnormal abrupt changes in adjacent measurement sections decrease, it is determined that a wall-attaching coupling state suitable for the transmission of stress and strain of the borehole wall has been formed between the armored optical cable and the borehole wall. SS5. Connect the armored optical cable to the distributed optical fiber demodulation equipment. After the wall-mounted coupling is completed, perform initial signal acquisition to obtain initial strain reference data, initial temperature reference data, or initial vibration response data of the armored optical cable distributed along the axial direction of the mine borehole. In the subsequent monitoring process, acquire the optical signal change information corresponding to the spiral layout path of the armored optical cable, and perform distributed measurement of the strain, deformation, or stress response of the mine borehole wall in the axial and / or circumferential range accordingly. SS6. When mining activities cause localized deformation of the borehole wall or a decrease in the adhesion of the armored optical cable, continue to rotate the adjusting nut to further expand the arc-shaped expansion piece radially outward and drive the expandable thin-walled sleeve to compensate for the expansion, maintaining the adhesion measurement state between the armored optical cable and the borehole wall. The adhesion state between the armored optical cable and the borehole wall is judged based on the continuity of the measurement signal along the borehole axis, the degree of abrupt changes in response of adjacent measurement sections, and the stability of repeatedly acquired signals in the same section. When there is signal attenuation in a local section, intermittent response, increased dispersion of repeatedly acquired signals, or a continuously increasing deviation from the initial reference data, it is determined that the adhesion state of the corresponding section may have decreased, and the adjusting nut is rotated to implement the compensation expansion. After each compensation expansion, distributed measurement data before and after compensation are collected and compared. When the continuity of the compensated signal improves, local abnormal fluctuations decrease, and the repeated acquisition results tend to stabilize, it is confirmed that the compensation expansion has met the requirements for maintaining the wall-adhesive measurement state.

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