Rock stress strain monitoring device for geological engineering

Abstract

The utility model relates to the technical field of stress-strain monitoring devices, and particularly discloses a rock stress-strain monitoring device for geological engineering, which comprises a fiber grating sensor and a buried hole port fixing device, and the buried hole port fixing device comprises a through hole expansion pipe and a threaded lock rod; the through hole expansion pipe is of a penetrating cylindrical structure, internal threads are arranged on the circumferential inner wall of the through hole expansion pipe, an expansion gap is formed in the through hole expansion pipe, and anti-disengaging barb protruding nails are arranged on the circumferential outer wall of the through hole expansion pipe. External threads are arranged on the circumferential outer wall of the threaded lock rod, the external threads are in threaded connection with the internal threads, a hexagonal-prism-shaped wrench position is arranged at the right end of the threaded lock rod, and an optical fiber hole is formed in the threaded lock rod; the fiber grating sensor comprises a filament-shaped optical fiber section and an optical fiber connector. The end, close to the optical fiber connector, of the optical fiber section is rotationally connected into the optical fiber hole. The device has the advantages of high precision, high stability and simplicity and convenience in installation, and provides a reliable monitoring means for geological engineering and engineering safety.

Description

Technical Field

[0001] The utility model relates to the technical field of stress and strain monitoring devices, in particular to a rock stress and strain monitoring device for geological engineering. Background Art

[0002] Rock stress and strain monitoring devices in geological engineering are devices used to monitor and record changes in rock stress and strain states during crustal movement, engineering construction, or other natural and human activities. These devices are essential for understanding the mechanical behavior of rocks, predicting geological disasters, optimizing engineering design, and ensuring construction safety.

[0003] At present, most of the existing rock stress and strain monitoring devices still have the defects of complex installation and poor accuracy. For example, the Chinese invention patent with patent application number 201110357267.2 discloses a rock stress and strain monitor for coal mines, which measures the range and dynamic change process of the external stress field in front of the coal mining face and outside the chute in real time by detecting the change of pressure liquid, and uploads the data to the host computer software for analysis and processing through infrared communication or bus communication. The technical solution recorded in the application can only measure the pressure change in the pressure measuring tube placement area, but cannot accurately measure the specific position of the pressure measuring tube where the pressure is generated, and the accuracy is average.

[0004] Therefore, there is an urgent need for a new type of rock stress and strain monitoring device for geological engineering to provide an effective solution to the defects of the existing technology. Utility Model Content

[0005] The purpose of the utility model is to provide a rock stress and strain monitoring device for geological engineering to solve the problems raised in the above background technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A rock stress and strain monitoring device for geological engineering includes a fiber optic Bragg grating sensor and a buried hole port fixing device, wherein the buried hole port fixing device includes a through-hole expansion tube and a threaded locking rod; the through-hole expansion tube is a through-hole cylindrical structure, an internal thread is arranged on the circumferential inner wall of the through-hole expansion tube, an expansion joint is opened on the through-hole expansion tube, and anti-slip barb convex nails are arranged on the circumferential outer wall of the through-hole expansion tube; an external thread is arranged on the circumferential outer wall of the threaded locking rod, the external thread is threadedly connected with the internal thread, a hexagonal wrench position is arranged at the right end of the threaded locking rod, and a fiber hole is arranged inside the threaded locking rod; the fiber optic Bragg grating sensor includes a filamentary fiber segment and a fiber connector, and one end of the fiber segment close to the fiber connector is rotatably connected in the fiber hole.

[0008] Furthermore, the threaded locking rod is provided with a penetrating grouting hole and a vent hole, and the grouting hole is used to inject grouting cement into the rock wall hole where the fiber optic grating sensor is buried.

[0009] Furthermore, a tube edge extending in the radial direction is arranged on the right port of the through-hole expansion tube.

[0010] Furthermore, a sealing rubber ring is sleeved on the circumferential outer wall of the left end of the through-hole expansion tube.

[0011] Furthermore, an outwardly protruding limiting ring is provided on the circumferential outer wall at the right end of the optical fiber segment, the diameter of the limiting ring is larger than the diameter of the optical fiber hole, and the limiting ring abuts against the left end of the optical fiber hole.

[0012] Furthermore, the through-hole expansion tube is made of stainless steel.

[0013] Furthermore, a stainless steel seamless sleeve is sleeved on the circumferential outer surface of the optical fiber segment.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] 1. In the utility model, the fiber grating sensor has high sensitivity and high resolution, and can accurately sense the rock stress changes at various positions of the fiber segment; the buried hole port fixing device composed of the through-hole expansion tube and the threaded locking rod can provide stable support, ensuring that the fiber grating sensor can operate stably in the rock wall hole for a long time without being disturbed by the outside world; the fiber grating sensor can be fixed in the rock wall hole by rotating the wrench position of the threaded locking rod, and the installation process is simple and fast, reducing the installation cost. Therefore, the utility model has the advantages of high precision, high stability and easy installation, providing a reliable monitoring method for geological engineering and engineering safety.

[0016] 2. The grouting hole provided in the threaded locking rod of the utility model allows the grouting hole to inject the grouting slurry into the hole of the rock wall after the fiber grating sensor is buried. The use of the grouting slurry makes the fiber grating sensor more closely combined with the rock wall, improves the seismic resistance and stability of the device, reduces the influence of external factors on the sensor, and improves the precision and accuracy of stress and strain monitoring.

[0017] 3. In the utility model, the sealing rubber ring is sleeved on the circumferential outer wall of the left end of the through-hole expansion tube. When the through-hole expansion tube is inserted into the rock wall hole, the sealing rubber ring fits tightly against the hole wall to achieve sealing of the hole opening, thereby avoiding leakage when injecting caulking cement slurry.

[0018] 4. In the present invention, a stainless steel seamless sleeve is sleeved on the outer surface of the optical fiber segment, which not only protects the internal optical fiber grating, but also reduces the difficulty of inserting the optical fiber segment into the pre-buried hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a rock stress and strain monitoring device for geological engineering;

[0020] Figure 2 It is a structural decomposition diagram of a rock stress and strain monitoring device for geological engineering;

[0021] Figure 3 A schematic diagram of the structure of through-hole expansion in a rock stress and strain monitoring device for geological engineering;

[0022] Figure 4 It is a structural schematic diagram of a fiber grating sensor and a threaded locking rod in a rock stress and strain monitoring device for geological engineering;

[0023] Figure 5 It is a structural schematic diagram of a threaded locking rod in a rock stress and strain monitoring device for geological engineering;

[0024] Figure 6 The figure is an axial cross-section of a threaded locking rod in a rock stress and strain monitoring device for geological engineering.

[0025] In the figure: 1. Optical fiber segment; 2. Optical fiber connector; 3. Buried hole port fixing device; 4. Through hole expansion tube; 5. Threaded locking rod; 6. Sealing rubber ring; 7. Anti-slip barb convex nail; 8. Expansion joint; 9. Pipe edge; 10. Internal thread; 11. External thread; 12. Wrench position; 13. Optical fiber hole; 14. Grouting hole; 15. Vent hole; 16. Fiber Bragg grating sensor. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] Example 1: Please refer to Figures 1 to 6A rock stress and strain monitoring device for geological engineering includes a fiber grating sensor 16 and a buried hole port fixing device 3, wherein the buried hole port fixing device 3 includes a through-hole expansion tube 4 and a threaded locking rod 5; the through-hole expansion tube 4 is a through-hole cylindrical structure, an internal thread 10 is arranged on the circumferential inner wall of the through-hole expansion tube 4, an expansion joint 8 is opened on the through-hole expansion tube 4, and an anti-slip barb convex nail 7 is arranged on the circumferential outer wall of the through-hole expansion tube 4; an external thread 11 is arranged on the circumferential outer wall of the threaded locking rod 5, the external thread 11 is threadedly connected with the internal thread 10, a hexagonal wrench position 12 is arranged at the right end of the threaded locking rod 5, and a fiber hole 13 is arranged inside the threaded locking rod 5; the fiber grating sensor 16 includes a filamentary optical fiber segment 1 and an optical fiber connector 2, and the end of the optical fiber segment 1 close to the optical fiber connector 2 is rotatably connected in the optical fiber hole 13.

[0028] Working principle of this embodiment:

[0029] In this embodiment, the rock stress and strain monitoring device for geological engineering is based on the strain sensitivity of the fiber grating sensor 16 and the stability of the buried hole port fixing device 3. First, the through-hole expansion tube 4 is inserted into the pre-drilled rock wall hole. Since the through-hole expansion tube 4 is provided with an expansion joint 8, it can expand in the rock wall hole and fit closely to the hole wall, thereby providing stable support. At the same time, the anti-slip barb convex nail 7 provided on the circumferential outer wall of the through-hole expansion tube 4 can prevent it from slipping in the rock wall hole, ensuring the long-term stability of the device. Next, the filamentary optical fiber segment 1 of the fiber grating sensor 16 is passed through the optical fiber hole 13 inside the threaded locking rod 5, and one end of the optical fiber segment 1 is rotated and connected in the optical fiber hole 13, and the other end is connected to the optical fiber connector 2. The fiber grating sensor 16 can sense the changes in rock stress and strain and convert them into optical signals. Then, the left end of the threaded locking rod 5 is screwed into the internal thread 10 on the circumferential inner wall of the through-hole expansion tube 4, and the threaded locking rod 5 is tightly connected to the through-hole expansion tube 4 by rotating the hexagonal wrench position 12 at the right end of the threaded locking rod 5, so that the fiber grating sensor 16 is fixed in the rock wall hole. This connection method is not only simple and fast, but also can ensure that the fiber grating sensor 16 is not interfered by the outside world during the monitoring process. During the monitoring process, when the rock is subjected to stress and strain, the fiber grating sensor 16 will sense these changes and convert the changes into optical signals. These optical signals are transmitted to the external data acquisition and analysis system through the optical fiber connector 2 for processing and analysis, thereby obtaining the state change data of rock stress and strain.

[0030] In this embodiment, the fiber grating sensor 16 has high sensitivity and high resolution, and can accurately sense the rock stress changes at various positions of the optical fiber segment 1; the buried hole port fixing device 3 composed of the through-hole expansion tube 4 and the threaded locking rod 5 can provide stable support, ensuring that the fiber grating sensor 16 can operate stably in the rock wall hole for a long time without being disturbed by the outside world; the fiber grating sensor 16 can be fixed in the rock wall hole by rotating the wrench position 12 of the threaded locking rod 5, and the installation process is simple and fast, reducing the installation cost. Therefore, this embodiment has the advantages of high precision, high stability, and easy installation, providing a reliable monitoring method for geological engineering and engineering safety.

[0031] Example 2: Please refer to Figures 1-2 A rock stress and strain monitoring device for geological engineering is different from Example 1 in that a threaded locking rod 5 is provided with a penetrating grouting hole 14 and a vent hole 15, and the grouting hole 14 is used to inject grouting cement slurry into the rock wall hole where the fiber grating sensor 16 is buried.

[0032] The grouting hole 14 provided in the threaded locking rod 5 in this embodiment allows the grouting hole 14 to inject the grouting grout into the hole of the rock wall after the fiber Bragg grating sensor 16 is buried. The use of the grouting grout makes the fiber Bragg grating sensor 16 more closely combined with the rock wall, improves the shock resistance and stability of the device, reduces the influence of external factors on the sensor, and improves the precision and accuracy of stress and strain monitoring.

[0033] Example 3: Please refer to Figure 3 , a rock stress and strain monitoring device for geological engineering, which is different from Example 1 in that a tube edge 9 extending radially is provided on the right end of the through-hole expansion tube 4.

[0034] In this embodiment, when the through-hole expansion tube 4 is buried, the tube edge 9 can play a limiting role.

[0035] Example 4: Please refer to Figure 3 , a rock stress and strain monitoring device for geological engineering, which is different from Example 2 in that a sealing rubber ring 6 is sleeved on the circumferential outer wall of the left end of the through-hole expansion tube 4.

[0036] In this embodiment, the sealing rubber ring 6 is sleeved on the circumferential outer wall of the left end of the through-hole expansion tube 4. When the through-hole expansion tube 4 is inserted into the rock wall hole, the sealing rubber ring 6 fits tightly against the hole wall to achieve sealing of the hole opening, thereby avoiding leakage when injecting caulking cement slurry.

[0037] Example 5: Please refer to Figures 4-5 , a rock stress and strain monitoring device for geological engineering, which differs from Example 1 in that an outwardly protruding limit ring is provided on the circumferential outer wall at the right end of the optical fiber segment 1, the diameter of the limit ring is larger than the diameter of the optical fiber hole 13, and the limit ring is against the left end of the optical fiber hole 13.

[0038] In this embodiment, the limiting ring abuts against the left end of the optical fiber hole 13 to limit the optical fiber segment 1 and prevent the optical fiber segment 1 from slipping off the locking screw 5 .

[0039] Example 6: Please refer to Figure 3 , a rock stress and strain monitoring device for geological engineering, which is different from Example 1 in that the through-hole expansion tube 4 is made of stainless steel.

[0040] In this embodiment, the through-hole expansion tube 4 is made of stainless steel, which has the advantages of high strength and corrosion resistance.

[0041] Example 7: Please refer to Figures 1-2 , a rock stress and strain monitoring device for geological engineering, which differs from Example 1 in that a stainless steel seamless sleeve is sleeved on the circumferential outer surface of the optical fiber segment 1.

[0042] In this embodiment, a stainless steel seamless sleeve is sleeved on the outer surface of the optical fiber segment 1, which not only protects the internal optical fiber grating, but also reduces the difficulty of inserting the optical fiber segment 1 into the pre-buried hole.

Claims

1. A rock stress and strain monitoring device for geological engineering, comprising a fiber grating sensor (16) and a buried hole port fixing device (3), characterized in that: The buried hole port fixing device (3) comprises a through-hole expansion tube (4) and a threaded locking rod (5); the through-hole expansion tube (4) is a through-hole cylindrical structure, an internal thread (10) is arranged on the circumferential inner wall of the through-hole expansion tube (4), an expansion joint (8) is opened on the through-hole expansion tube (4), and an anti-slip barb convex nail (7) is arranged on the circumferential outer wall of the through-hole expansion tube (4); an external thread (11) is arranged on the circumferential outer wall of the threaded locking rod (5), the external thread (11) is threadedly connected with the internal thread (10), a hexagonal wrench position (12) is arranged at the right end of the threaded locking rod (5), and an optical fiber hole (13) is arranged inside the threaded locking rod (5); the optical fiber grating sensor (16) comprises a filamentary optical fiber segment (1) and an optical fiber connector (2), and the end of the optical fiber segment (1) close to the optical fiber connector (2) is rotatably connected in the optical fiber hole (13).

2. A rock stress and strain monitoring device for geological engineering according to claim 1, characterized in that: The threaded locking rod (5) is provided with a penetrating grouting hole (14) and a vent hole (15); the grouting hole (14) is used to inject grouting cement into a rock wall hole where a fiber optic grating sensor (16) is buried.

3. The rock stress and strain monitoring device for geological engineering according to claim 1, characterized in that: The right end port of the through-hole expansion tube (4) is provided with a tube edge (9) extending in the radial direction.

4. The rock stress and strain monitoring device for geological engineering according to claim 2, characterized in that: A sealing rubber ring (6) is sleeved on the circumferential outer wall of the left end of the through-hole expansion tube (4).

5. The rock stress and strain monitoring device for geological engineering according to claim 1, characterized in that: An outwardly protruding limiting ring is provided on the circumferential outer wall at the right end of the optical fiber segment (1); the diameter of the limiting ring is larger than the diameter of the optical fiber hole (13); the limiting ring abuts against the left end of the optical fiber hole (13).

6. The rock stress and strain monitoring device for geological engineering according to claim 1, characterized in that: The through-hole expansion tube (4) is made of stainless steel.

7. The rock stress and strain monitoring device for geological engineering according to claim 1, characterized in that: A stainless steel seamless sleeve is sleeved on the circumferential outer surface of the optical fiber segment (1).

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