A tunnel surrounding rock convergence monitoring device

Abstract

This utility model relates to the field of tunnel surrounding rock deformation measurement technology, specifically a tunnel surrounding rock convergence monitoring device. The device includes an arched support frame, monitoring mechanisms mounted on the arched support frame, and multiple monitoring mechanisms arranged along the length of the arched support frame. Each monitoring mechanism includes a guide sleeve slidably connected to the arched support frame, a pressure sensor fixedly connected to the bottom end of the guide sleeve, a monitoring rod passing through the inside of the guide sleeve, a spring positioned between the pressure sensor and the monitoring rod, and a drive assembly for moving the guide sleeve. This device uses an arched support frame adapted to the tunnel cross-section, with multiple monitoring mechanisms distributed along it, comprehensively covering multiple monitoring points and avoiding omissions. The monitoring mechanism, through the combination of "monitoring rod-spring-pressure sensor," converts the minute convergence displacement of the surrounding rock into a quantifiable electrical signal, achieving accurate measurement. The drive assembly can adjust the position of the guide sleeve, causing the monitoring rod to conform to the surrounding rock and pre-tightening the spring, improving monitoring sensitivity.

Description

Technical Field

[0001] This utility model relates to the field of tunnel surrounding rock deformation measurement technology, specifically a tunnel surrounding rock convergence monitoring device. Background Technology

[0002] During tunnel excavation, surrounding rock deformation is one of the core risks threatening project safety. Local collapses of loose and fractured rock masses, radial extrusion of soft and expansive soil, and precursors to rock bursts in hard rock masses are all characterized by "multi-directional non-uniform deformation." For example, the tunnel roof is prone to subsidence and deformation due to its own weight, the sidewalls may experience inward squeezing deformation due to horizontal ground stress, and the arch foot is often accompanied by a composite deformation of "radial contraction + slight tangential displacement." These deformations are often asynchronous and of different magnitudes, and if local deformation in any direction is not monitored in time, it may lead to a complete collapse accident.

[0003] Chinese patent CN202323350384.3 discloses "A Tunnel Surrounding Rock Deformation Measurement Device" (publication number CN221259767U). This device includes a main body, with a movable plate slidably mounted on one side of the main body and a toothed plate fixedly mounted on one side of the movable plate. A dial with a pointer is mounted above the toothed plate. The device also includes an electric tail rod inside the main body, with a mounting plate fixedly mounted below the electric tail rod. A sliding rod is positioned in the middle of the mounting plate, and fixed plates are arranged in a circular array on one side of the sliding rod. The electric tail rod provides power for the fixed plates to move on the mounting plate. The extension movement of the fixed plates supports the device in a through-hole. Changes in the surrounding rock cause the movable plate to slide passively, allowing the toothed plate to slide inside the main body, causing the pointer to swing on the dial. The reading indicated by the pointer after it stops on the dial allows for continuous measurement of the changes in the surrounding rock. However, the device has some drawbacks: it only relies on a set of "moving plate-transmission components" arranged on one side, which limits the monitoring range and makes it impossible to monitor the settlement of the surrounding rock of the tunnel arch. Utility Model Content

[0004] To address the problems of the prior art, this invention provides a tunnel surrounding rock convergence monitoring device that can measure the deformation of the surrounding rock at the tunnel arch from multiple angles, providing more reliable monitoring support for tunnel construction safety.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a tunnel surrounding rock convergence monitoring device, comprising an arched support frame, a monitoring mechanism mounted on the arched support frame, multiple monitoring mechanisms arranged along the length of the arched support frame, and the monitoring mechanism comprising a guide sleeve slidably connected to the arched support frame, a pressure sensor fixedly connected to the bottom end of the guide sleeve, a monitoring rod passing through the inside of the guide sleeve, a spring disposed between the pressure sensor and the monitoring rod, and a drive assembly for pushing the guide sleeve to move.

[0006] With the above structural design, multiple monitoring units are distributed along the arched support frame, which can simultaneously cover multiple monitoring points of the tunnel surrounding rock, avoiding the risk of missing local deformation of the surrounding rock at a single monitoring point. The monitoring unit uses a combination of "monitoring rod-spring-pressure sensor" to convert the small convergence displacement of the surrounding rock into changes in spring force, and then quantifies it into an electrical signal through the pressure sensor. Utilizing the linear relationship of Hooke's Law, it can achieve accurate measurement of the small convergence amount. The drive component can push the guide sleeve to move, which facilitates the adjustment of the fit between the monitoring rod and the surrounding rock during installation, ensuring that the spring is in a pre-tight state in the initial state, avoiding the failure of the sensor to respond to the small displacement of the surrounding rock in the early stage, and improving the monitoring sensitivity. The arched support frame is adapted to the arched cross-section structure of the tunnel and can fit the contour of the surrounding rock, ensuring the effectiveness of the contact between the monitoring rod and the surrounding rock, and avoiding displacement transmission distortion caused by installation angle deviation.

[0007] Preferably, both ends of the arched support frame are fixedly connected to the base plate, and anchor nails are installed on the base plate.

[0008] With the above structural design, the bottom plates at both ends of the arched support frame increase the contact area with the tunnel rock wall, disperse the anchoring pressure, and the anchoring nails installed on the bottom plates can firmly anchor the entire device and ensure that the support frame itself does not shift.

[0009] Preferably, symmetrically arranged sliders are fixedly connected to the guide sleeve, and a groove matching the slider is opened on the arched support frame, with the length of the slider being adapted to the length of the guide sleeve.

[0010] With the above structural design, the guide sleeve is matched with the groove of the arched support frame by the symmetrical slider, which limits the guide sleeve to slide in a straight line only in the radial direction of the arched support frame, avoiding the guide sleeve from deviating or twisting. The length of the slider is matched with the length of the guide sleeve, which increases the sliding contact area and improves the smoothness of the guide sleeve sliding.

[0011] Preferably, the drive assembly includes a support cylinder fixedly connected to the arched support frame, a drive rod threaded through the support cylinder, the upper end of the drive rod being rotatably connected to the bottom of the guide sleeve, and a handwheel fixedly connected to the drive rod.

[0012] With the above structural design, the upper end of the drive rod is rotatably connected to the guide sleeve, which prevents the guide sleeve from twisting when the drive rod rotates, ensuring that the guide sleeve moves only linearly along the slide groove. The threaded engagement between the support cylinder and the drive rod enables the drive rod to switch between rotation and linear displacement. The threaded structure has a self-locking function, and the position of the guide sleeve is not easy to loosen after adjustment, ensuring the stability of the monitoring status.

[0013] Preferably, the upper end of the drive rod is fixedly connected to the drive disc, and the bottom of the guide sleeve is provided with a stepped groove that matches the drive disc, so that the drive disc can be rotated and embedded in the stepped groove.

[0014] With the above structural design, the stepped groove structure does not require additional limiting components, which simplifies the connection structure and achieves the dual effect of "free rotation + axial fixation", which not only ensures driving efficiency, but also improves the ease of assembly and long-term operational stability of the device.

[0015] Compared with the prior art, the beneficial effects of this utility model are: This device uses an arched support frame adapted to the tunnel cross-section, with multiple monitoring units distributed along it to comprehensively cover multiple monitoring points and avoid missing local deformations. The monitoring unit uses a combination of a monitoring rod, spring, and pressure sensor, leveraging Hooke's Law to convert minute convergent displacements of the surrounding rock into quantifiable electrical signals for precise measurement. The drive assembly adjusts the position of the guide sleeve, ensuring the monitoring rod fits snugly against the surrounding rock and the spring is pre-tensioned, improving monitoring sensitivity while avoiding displacement transmission distortion caused by installation angle deviations, thus ensuring reliable monitoring data. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a front view structural diagram of the present invention; Figure 3 This is an enlarged structural schematic diagram of the monitoring mechanism of this utility model. Detailed Implementation

[0017] Please see Figure 1 , Figure 2 , Figure 3This utility model provides a technical solution: a tunnel surrounding rock convergence monitoring device, including an arched support frame 1 and a monitoring mechanism 2 disposed on the arched support frame 1. The monitoring mechanism 2 is provided in multiple sets and is arranged along the length direction of the arched support frame 1. The monitoring mechanism 2 is arranged in multiple sets at equal intervals along the length direction of the arched support frame 1. The monitoring mechanism 2 includes a guide sleeve 21 slidably connected to the arched support frame 1, a pressure sensor 22 fixedly connected to the bottom end of the guide sleeve 21, a monitoring rod 23 passing through the inside of the guide sleeve 21, a spring 24 disposed between the pressure sensor 22 and the monitoring rod 23, and a driving component for pushing the guide sleeve 21 to move. One end of the spring 24 is fixedly connected to the pressure sensor 22, and the other end of the spring 24 is fixedly connected to the monitoring rod 23. The guide sleeve 21 moves along the radial direction of the arched support frame 1.

[0018] Both ends of the arched support frame 1 are fixedly connected to the base plate 11, and anchor nails 12 are inserted through the base plate 11.

[0019] The guide sleeve 21 is fixedly connected to symmetrically arranged sliders 31. The arched support frame 1 has a sliding groove that matches the sliders 31. The length of the sliders 31 is adapted to the length of the guide sleeve 21 to improve the sliding stability of the guide sleeve 21.

[0020] The drive assembly includes a support cylinder 41 fixedly connected to the arched support frame 1, and a drive rod 42 threaded through the support cylinder 41. The upper end of the drive rod 42 is rotatably connected to the bottom of the guide sleeve 21. A handwheel 43 is fixedly connected to the drive rod 42, and a handwheel 43 for easy manual operation is fixedly connected to the lower end of the drive rod 42.

[0021] The upper end of the drive rod 42 is fixedly connected to the drive disk 44, and the upper end of the drive rod 42 is coaxially fixed with the drive disk 44. The bottom of the guide sleeve 21 is provided with a stepped groove 45 that is adapted to the drive disk 44, and the drive disk 44 is rotatably embedded in the stepped groove 45.

[0022] Working principle: During installation, the arched support frame 1 is firmly fixed inside the tunnel by the anchoring nails 12 on the base plate 11, so that the arched support frame 1 fits the tunnel cross-sectional profile. Turning the handwheel 43 moves the drive rod 42 along the threaded structure of the support cylinder 41, which drives the guide sleeve 21 to slide radially along the arched support frame 1 through the cooperation of the slider 31 and the groove, until the outer end of the monitoring rod 23 is in close contact with the surrounding rock of the tunnel. At this time, the spring 24 is in a pre-tightened state, and the pressure sensor 22 records the initial pressure value.

[0023] When the surrounding rock of the tunnel undergoes convergent deformation, it will generate a radial thrust on the monitoring rod 23, pushing the monitoring rod 23 to move into the guide sleeve 21, causing the spring 24 to be further compressed. The pressure sensor 22 detects the change in the elastic force of the spring 24 in real time and converts it into an electrical signal.

[0024] By comparing the real-time pressure value with the initial pressure value and combining the spring constant of spring 24, the displacement of monitoring rod 23 can be calculated in reverse. This displacement is the convergence deformation of the tunnel surrounding rock. Multiple sets of equally spaced monitoring devices 2 collect data simultaneously, achieving accurate and comprehensive monitoring of the convergence deformation of the entire tunnel surrounding rock.

[0025] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the content disclosed herein. They are not intended to limit the scope of this utility model and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this utility model, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this utility model. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this utility model's implementation.

[0026] The present invention has been described above with reference to preferred embodiments, but the scope of protection of the present invention is not limited thereto. All technical solutions falling within the scope of the claims are within the scope of protection of the present invention. Various modifications can be made to the present invention, and components can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way.

Claims

1. A device for monitoring convergence of tunnel surrounding rock, characterized in that: The system includes an arched support frame (1) and a monitoring mechanism (2) mounted on the arched support frame (1). Multiple monitoring mechanisms (2) are provided and are arranged along the length of the arched support frame (1). The monitoring mechanism (2) includes a guide sleeve (21) slidably connected to the arched support frame (1), a pressure sensor (22) fixedly connected to the bottom end of the guide sleeve (21), a monitoring rod (23) passing through the inside of the guide sleeve (21), a spring (24) disposed between the pressure sensor (22) and the monitoring rod (23), and a drive assembly for pushing the guide sleeve (21) to move.

2. The tunnel surrounding rock convergence monitoring device according to claim 1, characterized in that: Both ends of the arched support frame (1) are fixedly connected to the base plate (11), and anchor nails (12) are inserted through the base plate (11).

3. The tunnel surrounding rock convergence monitoring device according to claim 1, characterized in that: The guide sleeve (21) is fixedly connected to symmetrically arranged sliders (31), and the arched support frame (1) has a groove that matches the sliders (31). The length of the sliders (31) is adapted to the length of the guide sleeve (21).

4. A tunnel surrounding rock convergence monitoring device according to any one of claims 1 to 3, characterized in that: The drive assembly includes a support cylinder (41) fixedly connected to the arched support frame (1) and a drive rod (42) threaded through the support cylinder (41). The upper end of the drive rod (42) is rotatably connected to the bottom of the guide sleeve (21), and a handwheel (43) is fixedly connected to the drive rod (42).

5. The tunnel surrounding rock convergence monitoring device according to claim 4, characterized in that: The upper end of the drive rod (42) is fixedly connected to the drive disk (44), and the bottom of the guide sleeve (21) is provided with a stepped groove (45) that is adapted to the drive disk (44). The drive disk (44) is rotatably embedded in the stepped groove (45).

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