A monitoring system for cantilevered scaffolding

Abstract

This invention relates to the field of scaffolding inspection, specifically disclosing a monitoring system for cantilevered scaffolding. The system includes a fixed base connected to a building, with a monitoring box sleeved on the outside of the scaffolding uprights connected to the side of the fixed base. The uprights and the monitoring box are movable relative to each other. The monitoring box has an internal mounting cavity. A middle plate is fixed to the outer wall of the upright within the mounting cavity. The middle plate has at least one through hole located on the outside of the upright. A corresponding light source is positioned directly above the through hole. The diameter of the through hole is larger than the wavelength of the light emitted from the light source. Light passing through the through hole forms a light spot with the same shape as the through hole. A photosensitive element is located below the middle plate for receiving and monitoring changes in the area of ​​the light spot. This invention can monitor scaffolding settlement, is simple to use, has high monitoring efficiency, requires no visual observation, and provides accurate monitoring results.

Description

Technical Field

[0001] This invention relates to the field of scaffolding settlement monitoring technology, specifically to a cantilever scaffolding monitoring system. Background Technology

[0002] With rapid urbanization, more and more people are flocking to cities, making urban land increasingly valuable and buildings taller and taller. During construction, cantilevered scaffolding is installed on the exterior of buildings to support workers and support the installation of various equipment and the lifting and transportation of materials. The overall quality of cantilevered scaffolding structures in high-rise buildings cannot be ignored. When the bottom support columns (usually I-beams) are subjected to strong pressure, they will experience small-scale settlement. Generally, if the settlement distance is within the standard range, no correction of the scaffolding structure is required. However, if the settlement is large, it will have a significant impact on the load-bearing structure of the scaffolding and affect the overall structural stability. Therefore, it is necessary to install detection devices after the scaffolding is erected to monitor the settlement of the scaffolding.

[0003] In existing technologies, deformation and settlement of scaffolding are mainly monitored through levels, theodolites, and visual observation. Using instruments such as theodolites is cumbersome each time it is used, cannot be monitored, and has low monitoring efficiency. Visual observation, on the other hand, does not provide accurate monitoring results. Summary of the Invention

[0004] The purpose of this invention is to provide a cantilever scaffolding monitoring system that can monitor the settlement of scaffolding, is simple to use, has high monitoring efficiency, does not require visual observation, and provides accurate monitoring results.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following solution:

[0006] A cantilever scaffolding monitoring system includes a fixed base connected to a building. A monitoring box is connected to the side of the fixed base and sleeved on the outside of the uprights of the scaffolding. The uprights and the monitoring box can move relative to each other. The monitoring box has an installation cavity inside. An intermediate plate located in the installation cavity is fixed on the outer wall of the upright. The intermediate plate has at least one through hole located on the outside of the upright. A corresponding light source is located directly above the through hole. The diameter of the through hole is larger than the wavelength of the light emitted by the light source. After the light passes through the through hole, it forms a light spot with the same shape as the through hole. A photosensitive element for receiving and monitoring changes in the area of ​​the light spot is located below the intermediate plate.

[0007] In this scheme, the fixed base serves as the base of the monitoring system, which is firmly connected to the building structure to ensure the stability of the entire monitoring system. The monitoring box is fitted on the outside of the scaffold uprights and can move relative to the uprights. The internal space of the mounting cavity is used to accommodate the optical monitoring components. The intermediate plate is fixed to the outer wall of the uprights and moves synchronously with the uprights. The through hole is used to form a standard light spot, and its diameter must be larger than the wavelength of the light source to avoid the diffraction effect interfering with the shape of the light spot. The light source is located directly above the through hole and emits parallel or collimated light. The photosensitive element is located below the intermediate plate to receive the light spot and monitor its area change.

[0008] Initial state: When the pole is not deformed, the shape of the light spot is consistent with the through hole, and the photosensitive element records the initial light spot area.

[0009] Deformation monitoring: If the upright settles axially, the middle plate will also move, causing the relative position of the through hole and the light source to change, which in turn causes the light spot area to increase or decrease. The photosensitive element captures the changes in real time and transmits them to the data processing unit.

[0010] Data processing: By analyzing the change in light spot area using algorithms and combining it with calibration data (such as the linear relationship between light spot area and upright settlement), the actual settlement of the upright is calculated. A threshold can be set, and an alarm is triggered when the settlement exceeds the safe range. This method enables the monitoring of scaffold settlement, is simple to use, has high monitoring efficiency, requires no visual observation, and provides accurate monitoring results.

[0011] Optionally, the intermediate plate is provided with four through holes arranged in a cross shape. The through holes are circular or square. The top wall of the mounting cavity is provided with four mounting cylinders corresponding to the through holes. The light source is set on the top wall of the mounting cavity and located on the center line of the mounting cylinder. A flexible membrane is provided between the lower end of the mounting cylinder and the intermediate plate.

[0012] Optionally, a tension sensor is embedded within the flexible membrane.

[0013] Optionally, the intermediate plate is composed of two semi-circular plates, each with a semi-circular groove in the middle of its straight edge. When the two semi-circular plates are joined together, they form a circular groove in the middle that is compatible with the upright.

[0014] Optionally, the photosensitive element is a charge-coupled device (CCD), which is mounted on the bottom wall of the mounting cavity, with the photosensitive surface of the CCD facing the through hole.

[0015] Optionally, the number of photosensitive elements corresponds to the number of through holes.

[0016] Optionally, the photosensitive element is a single element, with a through hole in the center allowing the pole to pass through. The pole passes through the through hole, and a protective rubber ring is provided on the inner wall of the through hole.

[0017] Optionally, the top and bottom surfaces of the monitoring box are provided with mounting holes that allow the upright to pass through, and the upright passes through the two mounting holes axially.

[0018] Optionally, a sealing ring is provided on the inner wall of the assembly hole.

[0019] Optionally, the monitoring box is a rectangular structure consisting of a top plate, a bottom plate, a left plate, a right plate, a front plate, and a rear plate. The top plate, bottom plate, left plate, and right plate are fixedly connected to form a box with an opening on the front side. The upper end of the front plate is hinged to the front end of the top plate. The inner side of the front plate has a sealing gasket. The front plate is connected to the edge of the opening by screws or the front plate is connected to the box by wrapping tape.

[0020] The beneficial effects of this invention are as follows:

[0021] In this invention, when the upright is undeformed, the shape of the light spot matches the through hole, and the photosensitive element records the initial light spot area. If the upright experiences axial settlement, the intermediate plate also moves, causing a change in the relative position of the through hole and the light source, which in turn leads to an increase or decrease in the light spot area. The photosensitive element captures this change in real time and transmits it to the data processing unit. The algorithm analyzes the change in light spot area and, combined with calibration data (such as the linear relationship between light spot area and upright settlement), calculates the actual settlement of the upright. A threshold can be set, and an alarm is triggered when the settlement exceeds a safe range. This method enables the monitoring of scaffold settlement, is simple to use, has high monitoring efficiency, requires no visual observation, and provides accurate monitoring results. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the assembly structure of the invention and the upright;

[0023] Figure 2 This is a schematic diagram of the internal structure of the monitoring box when there are multiple photosensitive elements;

[0024] Figure 3 This is a schematic diagram of the internal structure of the monitoring box when there is one photosensitive element.

[0025] Figure 4 This is a schematic diagram showing light passing through a through-hole.

[0026] Figure 5 This is a structural diagram showing the structure when the middle plate is separated.

[0027] Figure 6 This is a structural diagram of the middle plates after they are joined together;

[0028] Figure 7 This is a structural diagram of the middle plate and uprights after assembly.

[0029] Figure 8 This is a structural diagram of the monitoring box.

[0030] Reference numerals: 1-Fixed base, 2-Monitoring box, 201-Top plate, 202-Bottom plate, 203-Front plate, 204-Assembly hole, 205-Left plate, 206-Right plate, 207-Rear plate, 208-Opening, 209-Sealing ring, 3-Light source, 4-Mounting cylinder, 5-Intermediate plate, 501-Semi-circular plate, 502-Circular groove, 5021-Semi-circular groove, 6-Through hole, 7-Photosensitive element, 8-Upright pole, 9-Exterior facade, 10-Cantilevered I-beam, 11-Mounting cavity, 12-Light spot, 13-Flexible membrane, 14-Through hole, 15-Protective rubber ring. Detailed Implementation

[0031] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0032] A cantilever scaffolding monitoring system includes a fixed base 1 connected to a building. A monitoring box 2 is connected to the side of the fixed base 1 and sleeved on the outside of the uprights 8 of the scaffolding. The uprights 8 and the monitoring box 2 can move relative to each other. The monitoring box 2 has an installation cavity 11 inside. An intermediate plate 5 located in the installation cavity 11 is fixed on the outer wall of the uprights 8. The intermediate plate 5 has at least one through hole 6 located on the outside of the uprights 8. A corresponding light source 3 is provided directly above the through hole 6. The diameter of the through hole 6 is larger than the wavelength of the light emitted by the light source 3. After the light passes through the through hole 6, it forms a light spot 12 with the same shape as the through hole 6. A photosensitive element 7 is provided below the intermediate plate 5 for receiving and monitoring the area change of the light spot 12.

[0033] In this embodiment, as Figure 1As shown, the fixed base 1 serves as the base of the monitoring system, firmly connected to the building structure to ensure the stability of the entire monitoring system. It is also necessary to ensure the levelness of the monitoring box 2. The monitoring box 2 is fitted onto the outside of the uprights 8 (steel pipes) of the scaffolding. One monitoring box 2 can be set every five or ten meters, or multiple monitoring boxes 2 can be set in key settlement areas. The uprights 8 of the scaffolding are set on the cantilevered I-beams 10, and the fixed base 1 is installed on the exterior facade 9 of the upper floor. After the uprights 8 are installed, the monitoring box 2 is installed. This allows for real-time monitoring of the settlement changes of the cantilevered scaffolding so that timely adjustments can be made. The monitoring box 2 and the uprights 8 can move relative to each other. The internal space of the mounting cavity 11 is used to accommodate the optical monitoring components. The mounting cavity 11 is a closed space to avoid external light affecting the monitoring results. A battery can be installed on the side wall of the mounting cavity 11 to power the light source 3 and the photosensitive element 7. Alternatively, it can be connected to an external power source through wires. The intermediate plate 5 is fixed to the outer wall of the upright 8 and moves synchronously with the upright 8. The through hole 6 is used to form a standard light spot 12. The diameter must be larger than the wavelength of the light source 3 to avoid the diffraction effect interfering with the shape of the light spot 12. The light source 3 is located directly above the through hole 6 and emits parallel light or collimated light (such as a combination of laser diode or LED and lens. The emitted beam must completely cover the through hole 6 to ensure that the shape of the light spot 12 is consistent with that of the through hole 6). The photosensitive element 7 is located below the intermediate plate 5, receives the light spot 12 and monitors its area change.

[0034] Initial state: When the pole 8 is not deformed, the shape of the light spot 12 is consistent with the through hole 6, and the photosensitive element 7 records the area of ​​the initial light spot 12.

[0035] Deformation monitoring: If the upright 8 experiences axial settlement, the intermediate plate 5 will also move, causing a change in the relative position of the through hole 6 and the light source 3, which in turn will cause the area of ​​the light spot 12 to increase or decrease. The photosensitive element 7 captures the changes in real time and transmits them to the data processing unit. If the upright 8 tilts or bends, it will also cause a change in the relative position of the through hole 6 and the light source 3, thus changing the shape of the light spot 12. For example, if the through hole 6 is circular, then the light spot 12 may be elliptical. By comparing the shape of the light spot 12, it is also possible to determine whether the upright 8 is tilted or deformed.

[0036] Data processing: By analyzing the change in the area of ​​light spot 12 using algorithms and combining it with calibration data (such as the linear relationship between the area of ​​light spot 12 and the settlement of pole 8), the actual settlement of pole 8 is calculated. A threshold can be set to trigger an alarm when the settlement exceeds the safe range. Specifically, for example... Figure 4As shown, the area of ​​the light spot 12 is defined as S1, the area of ​​the through hole 6 is S0, the distance from the light source 3 to the through hole 6 is L, and the distance from the through hole 6 to the photosensitive element 7 is D. The area of ​​the light spot 12 increases linearly with the increase of L (following the principle of similar triangles). S0 is a constant value and can be directly calculated from the aperture. Both the initial and the changed S1 can be calculated from the photosensitive element 7, thus obtaining the radius of the light spot 12. The value of L+D is constant and can be measured initially. Based on the tangent function relationship, the changed D can be obtained and compared with the initial D to determine the displacement of the upright 8 settlement. Similarly, the changed L can be obtained and compared with the initial L. This method enables the monitoring of scaffold settlement, is simple to use, has high monitoring efficiency, requires no visual observation, and provides accurate monitoring results.

[0037] Furthermore, the intermediate plate 5 is provided with four through holes 6 arranged in a cross shape. The through holes 6 are circular or square. The top wall of the mounting cavity 11 is provided with four mounting cylinders 4 corresponding to the through holes 6. The light source 3 is located on the top wall of the mounting cavity 11 and is located on the center line of the mounting cylinder 4. A flexible membrane 13 is provided between the lower end of the mounting cylinder 4 and the intermediate plate 5.

[0038] Specifically, such as Figure 2 As shown, the flexible membrane 13 is a cylindrical structure. Both the mounting cylinder 4 and the flexible membrane 13 are opaque. The four through holes 6 are arranged in a cross shape, which can simultaneously monitor the deformation of the pole 8 in two orthogonal directions (horizontal / vertical). By comparing the changes in the four light spots 12, the monitoring results can be cross-verified, and single-point faults or local interference (such as dust obstruction) can be eliminated.

[0039] The circular through-hole 6 and the shape of the light spot 12 have low sensitivity to the alignment error of the light source 3, making them suitable for rapid installation. The area of ​​the light spot 12 is linearly related to the displacement, which simplifies data processing and is suitable for construction sites that require high-frequency and automated monitoring.

[0040] The square through-hole 6 provides sharper edges for the light spot 12 and higher displacement resolution (capable of detecting micron-level deformation); the aspect ratio of the light spot 12 can be defined to distinguish between axial tension and bending deformation, making it suitable for structural health monitoring with extremely high precision requirements (such as the protection of historical buildings).

[0041] Each through-hole 6 corresponds to an independent mounting cylinder 4 to prevent crosstalk between adjacent light sources 3 and ensure the purity of the light spot 12. The inner wall of the mounting cylinder 4 can be coated with a reflective layer or fitted with a lens group to compress the divergence angle of the light source 3 to within ±1°, ensuring a clear edge of the light spot 12. The mounting cylinder 4 can isolate external mechanical impacts (such as scaffolding vibrations) to prevent the light source 3 from shifting or being damaged. The light source 3 is located on the center line of the mounting cylinder 4, coinciding with the axis of the through-hole 6, eliminating measurement errors introduced by the eccentricity of the light source 3.

[0042] A flexible membrane 13 is provided between the mounting cylinder 4 and the intermediate plate 5. The flexible membrane 13 connects the mounting cylinder 4 and the intermediate plate 5, thus preventing light leakage or external light interference. The flexible membrane 13 (such as silicone or TPU material) seals the gap between the mounting cylinder 4 and the intermediate plate 5, preventing rainwater, concrete slurry, etc. from entering the mounting cavity 11, thereby extending the equipment's lifespan. The thermal expansion coefficient of the flexible membrane 13 matches that of the metal intermediate plate 5, reducing the deformation of the optical components caused by temperature differences.

[0043] The flexible connection allows relative displacement between the intermediate plate 5 and the mounting cylinder 4 within ±2mm (e.g., when the pole 8 is shaken by wind), avoiding breakage of optical components caused by rigid connections. The elastic force of the flexible membrane 13 allows the intermediate plate 5 to automatically return to its original position after deformation, ensuring monitoring continuity. The flexible membrane 13 can absorb high-frequency vibrations (e.g., impacts from construction machinery), reducing the amplitude of light spot 12 jitter and improving data stability.

[0044] Specific monitoring procedures:

[0045] Initial calibration: Under no-load conditions on the pole 8, record the initial area and shape parameters of the four light spots 12 (such as the diameter of the circular light spot 12 and the side length of the square light spot 12), and establish a calibration curve of the change of light spot 12 and the displacement of the pole 8 (by applying a known displacement using a tensile and compressive testing machine).

[0046] Real-time monitoring: The photosensitive element 7 captures the image of the light spot 12 at a frequency of 100Hz. The area change is calculated by the edge detection algorithm. Combined with the data of the four light spots 12, the two-dimensional displacement vector (ΔX, ΔY) of the pole 8 can be calculated. For example, if the area of ​​the upper left light spot 12 increases and the area of ​​the lower right light spot 12 decreases, it can be inferred that the pole 8 is bending in the upper left direction.

[0047] Furthermore, a tension sensor is embedded within the flexible membrane 13.

[0048] Specifically, high-elasticity silicone or TPU (thermoplastic polyurethane) with a thickness of 0.5-1mm is selected, balancing flexibility and durability. Miniature tensile sensors (such as strain gauges or fiber optic gratings) are bonded to the inner surface of the flexible membrane 13 using conductive adhesive, and covered with a protective layer. During the injection molding of the flexible membrane 13, the sensors are pre-embedded inside the membrane to avoid direct exposure to harsh environments. The tensile sensors are evenly distributed circumferentially along the flexible membrane 13 (e.g., four sensors are arranged in a cross shape, corresponding to the through-hole 6) to capture multidimensional stress changes. The sensors can be connected to the data acquisition module inside the monitoring box 2 via a flexible printed circuit board (FPC) or shielded cable. The connection points are encapsulated with epoxy resin, achieving an IP68 protection rating to withstand rain and snow. When the pole 8 settles or bends, the intermediate plate 5 causes the flexible membrane 13 to deform, and the tensile sensors output a tensile signal related to displacement. Combined with the area change data of the light spot 12, the accuracy of the pole 8 settlement monitoring is further improved.

[0049] The amplitude and frequency of the tension signal can reflect the dynamic load (such as wind vibration and construction impact) on the upright 8. For example, if the frequency of the tension fluctuation coincides with the natural frequency of the scaffold (such as 2-5Hz), it indicates that there may be a risk of resonance.

[0050] Furthermore, the intermediate plate 5 is composed of two semi-circular plates 501. The semi-circular plates 501 have a semi-circular groove 5021 in the middle of their straight edges. When the two semi-circular plates 501 are joined together, the middle part forms a circular groove 502 that is compatible with the upright 8.

[0051] Specifically, such as Figure 5 , Figure 6 , Figure 7 As shown, in order to facilitate the installation of the intermediate plate 5, the intermediate plate 5 can be set as two symmetrical semi-circular plates 501. Each semi-circular plate 501 has two through holes 6. After the two semi-circular plates 501 are closed, the through holes 6 are arranged in a cross shape. The middle of the straight edge of the semi-circular plate 501 is provided with a semi-circular groove 5021. The two semi-circular grooves 5021 are closed to form a circular groove 502 that is compatible with the upright 8. The two semi-circular plates 501 can be fixed to the upright 8 by adhesive or bolt connection.

[0052] Furthermore, the photosensitive element 7 is a charge coupler, which is mounted on the bottom wall of the mounting cavity 11, with the photosensitive surface of the charge coupler facing the through hole 6.

[0053] Furthermore, the number of photosensitive elements 7 corresponds to the number of through holes 6.

[0054] Furthermore, the photosensitive element 7 is a single unit, and the photosensitive element 7 has a through hole 14 in the middle that allows the upright rod 8 to pass through. The upright rod 8 passes through the through hole 14, and a protective rubber ring 15 is provided on the inner wall of the through hole 14.

[0055] Specifically, such as Figure 3 As shown, when there is only one photosensitive element 7, the photosensitive element 7 needs to be specially designed. The middle part needs to be designed with a through hole 14 for the pole 8 to pass through. In order to prevent the pole 8 from settling and damaging the photosensitive element 7, a protective rubber ring 15 can be set on the inner wall of the through hole 14.

[0056] Furthermore, the top and bottom surfaces of the monitoring box 2 are provided with mounting holes 204 that allow the upright rod 8 to pass through, and the upright rod 8 passes through the two mounting holes 204 axially.

[0057] Furthermore, a sealing ring 209 is provided on the inner wall of the assembly hole 204.

[0058] Specifically, the sealing ring 209 can prevent external dust and rainwater from entering the monitoring box 2. It can also prevent external light from entering the monitoring box 2 and affecting the monitoring results.

[0059] Furthermore, the monitoring box 2 is a rectangular structure composed of a top plate 201, a bottom plate 202, a left plate 205, a right plate 206, a front plate 203, and a rear plate 207. The top plate 201, bottom plate 202, left plate 205, and right plate 206 are fixedly connected to form a box body with an opening 208 on the front side. The upper end of the front plate 203 is hinged to the front end of the top plate 201. The inner side of the front plate 203 has a sealing gasket. The front plate 203 is connected to the edge of the opening 208 by screws or the front plate 203 is connected to the box body by wrapping tape.

[0060] Specifically, such as Figure 8 As shown, during installation, the lower end of the pole 8 passes directly through the mounting holes 204 on the top plate 201 and the bottom plate 202, so that the monitoring box 2 is suspended and kept horizontal. Then, the fixing seat 1 is installed on the side wall of the building with expansion bolts. The front plate 203 is opened, the middle plate 5 is connected to the pole 8, and the position of the through hole 6 is adjusted to correspond to the light source 3. Then, the lower end of the flexible membrane 13 is connected to the middle plate 5, which can be done by adhesive bonding. Finally, the front plate 203 is fixed and completely sealed, and the settlement monitoring of the pole 8 can begin.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Based on the technical essence of the present invention, any simple modifications, equivalent substitutions, and improvements made to the above embodiments within the spirit and principles of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A cantilever scaffolding monitoring system, comprising a fixed base (1) connected to a building, characterized in that, The fixed base (1) is connected to a monitoring box (2) sleeved on the outside of the upright (8) of the scaffold. The upright (8) and the monitoring box (2) can move relative to each other. The monitoring box (2) has an installation cavity (11) inside. An intermediate plate (5) located in the installation cavity (11) is fixed on the outer wall of the upright (8). The intermediate plate (5) is provided with at least one through hole (6) located on the outside of the upright (8). A corresponding light source (3) is provided directly above the through hole (6). The diameter of the through hole (6) is larger than the wavelength of the light emitted by the light source (3). After the light passes through the through hole (6), it forms a light spot (12) with the same shape as the through hole (6). A photosensitive element (7) for receiving and monitoring the area change of the light spot (12) is provided below the intermediate plate (5).

2. The cantilever scaffolding monitoring system according to claim 1, characterized in that, The intermediate plate (5) is provided with four through holes (6) arranged in a cross shape. The through holes (6) are circular or square. The top wall of the mounting cavity (11) is provided with four mounting cylinders (4) corresponding to the through holes (6). The light source (3) is set on the top wall of the mounting cavity (11) and located on the center line of the mounting cylinder (4). A flexible membrane (13) is provided between the lower end of the mounting cylinder (4) and the intermediate plate (5).

3. The cantilever scaffolding monitoring system according to claim 2, characterized in that, A tension sensor is embedded in the flexible membrane (13).

4. The cantilever scaffolding monitoring system according to claim 2, characterized in that, The intermediate plate (5) is composed of two semi-circular plates (501). The semi-circular plates (501) have a semi-circular groove (5021) in the middle of their straight edges. When the two semi-circular plates (501) are joined together, a circular groove (502) is formed in the middle that is compatible with the upright (8).

5. The cantilever scaffolding monitoring system according to claim 1, characterized in that, The photosensitive element (7) is a charge coupler, which is mounted on the bottom wall of the mounting cavity (11), with the photosensitive surface of the charge coupler facing the through hole (6).

6. The cantilever scaffolding monitoring system according to claim 5, characterized in that, The number of photosensitive elements (7) corresponds to the number of through holes (6).

7. A cantilever scaffolding monitoring system according to claim 5, characterized in that, The photosensitive element (7) is a single unit. The photosensitive element (7) has a through hole (14) in the middle that allows the upright (8) to pass through. The upright (8) passes through the through hole (14), and a protective rubber ring (15) is provided on the inner wall of the through hole (14).

8. A cantilever scaffolding monitoring system according to claim 1, characterized in that, The monitoring box (2) has mounting holes (204) on its top and bottom surfaces that allow the upright (8) to pass through. The upright (8) passes through the two mounting holes (204) axially.

9. A cantilever scaffolding monitoring system according to claim 8, characterized in that, The inner wall of the assembly hole (204) is provided with a sealing ring (209).

10. A cantilever scaffolding monitoring system according to claim 8, characterized in that, The monitoring box (2) is a rectangular structure consisting of a top plate (201), a bottom plate (202), a left plate (205), a right plate (206), a front plate (203), and a rear plate (207). The top plate (201), bottom plate (202), left plate (205), and right plate (206) are fixedly connected to form a box with an opening (208) on the front side. The upper end of the front plate (203) is hinged to the front end of the top plate (201). The inner side of the front plate (203) has a sealing gasket. The front plate (203) is connected to the edge of the opening (208) by screws or the front plate (203) is connected to the box by wrapping tape.

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