A monitoring device for a plastic sheet pile cutoff wall based on optical fiber sensing technology

Abstract

The utility model provides a kind of plastic steel sheet pile cutoff wall monitoring device based on optical fiber sensing technology, including joint leakage monitoring unit: initiative heating type temperature vibration composite sensing optical cable is vertically laid along the joint of plastic steel sheet pile, is fixed by horse buckle;Horizontal displacement monitoring unit: miniature fixed-point dense distributed strain sensing optical cable is symmetrically laid in the both sides of plastic steel sheet pile, surface is covered with carbon fiber protective layer;Interface separation monitoring unit: low mode fixed-point dense distributed strain sensing optical cable is fixed in plastic steel sheet pile by custom fixture interval;Wall defect detection unit.The monitoring device utilizes optical fiber sensing technology, can real-time acquisition various monitoring data, timely discover the abnormal situation appeared in the service process of plastic steel sheet pile cutoff wall, provide timely basis for taking corresponding treatment measures;The device has the advantages of full-face distributed measurement, multi-parameter coupling analysis and strong anti-interference capability, significantly improves the operation safety early warning capability of cutoff wall.

Description

Technical Field

[0001] This utility model relates to the field of water conservancy engineering safety monitoring technology, and in particular to a monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology. Background Technology

[0002] Plastic-coated steel sheet piles are spliced ​​and cast into a cement-soil wall to serve as a cutoff wall. During long-term use, leakage may occur along the joints on the water-facing side due to water flow. Simultaneously, due to the horizontal pressure on the cutoff wall and defects caused by uneven cement-soil casting, problems such as horizontal deformation, delamination between the cement-soil and the plastic-coated steel sheet piles, and structural defects may arise. If these problems are not detected and addressed promptly, they will severely affect the seepage prevention effect of the cutoff wall. Currently, traditional monitoring methods have shortcomings such as low monitoring accuracy, inability to monitor in real time, and difficulty in comprehensively reflecting the structural condition, failing to meet the needs of safety monitoring of plastic-coated steel sheet pile cutoff walls. Utility Model Content

[0003] (a) Technical problems to be solved

[0004] To address the shortcomings of existing technologies, this utility model provides an integrated, high-precision multi-parameter real-time monitoring system for plastic steel sheet pile cutoff walls, enabling synchronous distributed sensing of joint leakage, horizontal deformation, interface delamination, and wall defects.

[0005] (II) Technical Solution

[0006] To achieve the above objectives, this utility model provides the following technical solution: a monitoring device for plastic-steel sheet pile cutoff walls based on fiber optic sensing technology, comprising four types of fiber optic sensing units and their deployment structure.

[0007] 1. Joint Leakage Monitoring Unit:

[0008] Structure: Active heating type temperature vibration composite sensing optical cable is laid vertically along the joint of sheet pile, and fixed to the surface of sheet pile at 1m intervals by saddle clips, which are glued with high-strength adhesive (such as Goodlite).

[0009] principle:

[0010] ①Temperature method: Actively heat the optical cable and locate the leakage point in the area by monitoring abnormal temperature increments;

[0011] ② Vibration method: Capture the acoustic vibration signal of the leaking water flow to assist in the identification and location of the leak.

[0012] 2. Sheet pile horizontal displacement monitoring unit:

[0013] Structure: Miniature fixed-point densely distributed strain sensing optical cables are symmetrically arranged on both sides of the maximum section of the sheet pile. After pre-tensioning, the optical cables are bonded with high-strength adhesive, and the surface is covered with carbon fiber cloth and reinforced and protected with impregnated glue.

[0014] Principle: The curvature of the sheet pile is calculated based on the strain difference (Δε) between the two optical cables, and then the horizontal displacement is calculated by integration. The spatial resolution reaches 0.5m and the accuracy is 0.1mm / m.

[0015] 3. Sheet pile-cement-soil interface delamination monitoring unit:

[0016] Structure: Low-modal fixed-point dense distributed strain sensing optical cables are laid next to the displacement monitoring optical cable. Every two sensing points are vertically fixed to the surface of the sheet pile by custom clamps, and the unfixed points are coupled to the cement soil.

[0017] Principle: Delamination causes tension on the optical cable between the fixed point on the sheet pile side and the soil side; the pure delamination deformation is obtained by deducting the deformation of the sheet pile itself (provided by the displacement monitoring unit), with a range of 20mm / m and an accuracy of 0.01mm / m.

[0018] 4. Wall Defect Detection Unit:

[0019] structure:

[0020] ① Horizontal direction: The metal-based cable-like distributed strain sensing optical cable passes through the threading ring welded to the sheet pile and is laid horizontally straight;

[0021] ② Vertical: Distributed foamed spiral vibration sensing optical cable is fixed to the side of the sheet pile by clips.

[0022] principle:

[0023] Vibration imaging: Acquire horizontal and vertical optical cable vibration signals, and identify the location and size of defects through imaging algorithms;

[0024] Global deformation: Horizontal metal-based optical cables synchronously monitor the overall strain distribution of the wall.

[0025] (III) Beneficial Effects

[0026] This invention provides a monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology.

[0027] It has the following beneficial effects:

[0028] 1. The fiber optic sensing technology-based plastic steel sheet pile cutoff wall monitoring device provides real-time monitoring: This monitoring device utilizes fiber optic sensing technology to collect various monitoring data in real time, promptly detect abnormalities in the plastic steel sheet pile cutoff wall, and provide timely basis for taking corresponding treatment measures.

[0029] 2. This fiber optic sensing technology-based plastic steel sheet pile cutoff wall monitoring device provides high-precision monitoring: Each monitoring module adopts high-precision sensing optical cables and advanced monitoring principles, which can accurately measure parameters such as joint leakage, sheet pile horizontal displacement, sheet pile-cement soil interface delamination, and wall defects, thereby improving the accuracy and reliability of monitoring.

[0030] 3. This fiber optic sensing technology-based monitoring device for plastic steel sheet pile cutoff walls provides comprehensive monitoring: the system covers a variety of potential risk factors for plastic steel sheet pile cutoff walls, enabling comprehensive monitoring of the cutoff wall structure, timely detection of potential safety hazards, and ensuring the safe operation of the cutoff wall.

[0031] 4. The monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology has good stability: fiber optic sensing technology has the advantages of anti-electromagnetic interference and corrosion resistance, and can work stably for a long time in harsh environments, reducing the maintenance cost and failure rate of the monitoring system. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the joint leakage monitoring structure of this utility model;

[0033] Figure 2 This is a schematic diagram of the horizontal displacement monitoring structure of this utility model;

[0034] Figure 3 This is a schematic diagram of the interface delamination monitoring structure of this utility model;

[0035] Figure 4 This is a schematic diagram of the wall defect detection structure of this utility model.

[0036] In the diagram: 1. Joint leakage monitoring unit; 11. Active heating type temperature vibration composite sensing optical cable; 12. Saddle buckle; 2. Horizontal displacement monitoring unit; 21. Miniature fixed-point dense distributed strain sensing optical cable; 22. Carbon fiber cloth; 3. Interface delamination monitoring unit; 31. Low-modal fixed-point dense distributed strain sensing optical cable; 33. Cement soil; 4. Wall defect detection unit; 41. Metal-based cable-like distributed strain sensing optical cable; 42. Distributed foamed spiral vibration sensing optical cable; 43. Threading ring; 5. Plastic steel sheet pile. Detailed Implementation

[0037] This utility model embodiment provides a monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology, such as Figure 1-4 As shown,

[0038] like Figure 1 As shown, the joint leakage monitoring unit consists of an active heating type temperature vibration composite sensing optical cable laid vertically along the joint and fixed by a saddle clip.

[0039] like Figure 2As shown, the horizontal displacement monitoring unit consists of miniature fixed-point densely distributed strain sensing optical cables symmetrically arranged on both sides of the sheet pile, with the surface covered by a carbon fiber protective layer.

[0040] like Figure 3 As shown, the interface delamination monitoring unit consists of a low-modal fixed-point densely distributed strain sensing optical cable that is fixed to the sheet pile at intervals using customized clamps, with the unfixed points coupled to the cement-soil.

[0041] In the actual installation process, the splicing of plastic steel sheet piles and the pouring of cement-soil walls are carried out first in accordance with the design requirements.

[0042] For the joint leakage monitoring component, after the plastic steel sheet piles are spliced, the active heating type temperature vibration composite sensing optical cable is vertically laid along the joint and fixed to the surface of the sheet pile with a saddle clip every 1m using a Gudelai adhesive to ensure that the optical cable is tightly attached to the sheet pile.

[0043] When installing the sheet pile horizontal displacement monitoring component, on both sides of the largest section of the plastic steel sheet pile, first apply a pre-tension to the micro fixed-point dense distributed strain sensing optical cable using Goodlite before pasting it, then lay carbon fiber cloth and repeatedly apply impregnating adhesive to fix it, ensuring that the optical cable is not damaged during the lowering of the sheet pile.

[0044] The sheet pile-cement-soil interface delamination monitoring component involves laying low-modal fixed-point densely distributed strain sensing optical cables near the sheet pile horizontal displacement monitoring optical cables. Every two fixed points, customized clamps are used to vertically fix the optical cables to the sheet pile surface using adhesive adhesive, thus completing the pre-tensioning and laying of the optical cables.

[0045] like Figure 4 As shown, when installing the wall defect detection component, the threading ring is first welded to the surface of the plastic steel sheet pile. Then, the metal-based cable-like distributed strain sensing optical cable is passed through the ring and lowered with the sheet pile. At the same time, the distributed foamed spiral vibration sensing optical cable is fixed to the side surface of the sheet pile with a clip and glued with a glue stick, and lowered to the predetermined position together with the sheet pile.

[0046] After installation, the data collected by each monitoring component is analyzed in real time through the corresponding signal acquisition and processing system. Based on the set threshold, it is determined whether there are any abnormalities in the cutoff wall. Once a problem is detected, an early warning is issued in time so that corresponding measures can be taken.

[0047] 1. Fiber optic cable laying:

[0048] First, clean the surface of the sheet piles and then use a high-strength adhesive (such as Goodlite) to fix the clamps.

[0049] Joint optical cables, displacement optical cables, and delamination optical cables are laid vertically, while defect detection optical cables are laid horizontally and vertically.

[0050] After the metal-based cable-like optical cable is inserted into the ring, it is adjusted to a horizontal and taut state.

[0051] 2. Data Collection:

[0052] Temperature-vibration composite optical cable: alternating / synchronous acquisition of temperature field and vibration signals;

[0053] Strain fiber optic cable: Real-time acquisition of strain distribution, with data from displacement and delamination elements linked for calculation;

[0054] Vibrating optical cable: Acquires sound / vibration signals and performs three-dimensional imaging.

[0055] Beneficial effects

[0056] 1. Multi-parameter integration: A single system simultaneously monitors four types of risks: leakage, deformation, delamination, and defects;

[0057] 2. High-precision positioning: Distributed measurement achieves a spatial resolution of 0.5m across the entire cross-section, with a delamination detection accuracy of 0.01mm / m;

[0058] 3. Anti-interference design:

[0059] Carbon fiber cloth protects strain-resistant optical cables, enhancing their durability;

[0060] The delamination monitoring unit eliminates sheet pile deformation interference by comparing displacement data;

[0061] The threaded loop structure ensures that the horizontal optical cable can expand and contract freely, avoiding stress concentration.

[0062] 4. Dual verification: Leakage monitoring combined with temperature and vibration methods improves reliability.

[0063] In summary, this device has the advantages of full-section distributed measurement, multi-parameter coupled analysis, and strong anti-interference ability, which significantly improves the early warning capability of cutoff wall operation safety.

[0064] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A monitoring device for plastic-steel sheet pile cutoff walls based on fiber optic sensing technology, characterized in that, include: Joint leakage monitoring unit (1): Active heating type temperature vibration composite sensing optical cable (11) is vertically laid along the joint of plastic steel sheet pile (5) and fixed by saddle buckle (12); Horizontal displacement monitoring unit (2): Miniature fixed-point dense distributed strain sensing optical cable (21) is symmetrically arranged on both sides of plastic steel sheet pile (5), and the surface is covered with carbon fiber protective layer (22); Interface delamination monitoring unit (3): Low-modal fixed-point dense distributed strain sensing optical cable (31) is fixed to plastic steel sheet pile (5) at intervals by customized clamps, and the unfixed points are coupled to cement soil (33); Wall defect detection unit (4): includes a horizontal metal-based cable-like distributed strain sensing optical cable (41) and a vertical distributed foamed spiral vibration sensing optical cable (42).

2. The monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology according to claim 1, characterized in that: The joint leakage monitoring unit (1) adopts a dual verification mechanism of temperature method and vibration method.

3. The monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology according to claim 1, characterized in that: The strain difference between the two optical cables of the horizontal displacement monitoring unit (2) is used to calculate the curvature and horizontal displacement of the sheet pile.

4. The monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology according to claim 1, characterized in that: The data from the interface delamination monitoring unit (3) needs to be reduced by the deformation of the horizontal displacement monitoring unit.

5. The monitoring device for plastic steel sheet pile cutoff wall based on fiber optic sensing technology according to claim 1, characterized in that: The metal-based cable-like distributed strain sensing optical cable (41) passes through the threading ring (43) welded to the plastic steel sheet pile (5) to achieve horizontal free expansion and contraction.

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