Rock-fill dam multi-type settlement monitoring system and data processing method

Abstract

The invention discloses a rock-fill dam multi-type settlement monitoring system and a data processing method, and belongs to the technical field of hydraulic engineering and geotechnical engineering. Aiming at the problems of monitoring blind areas, insufficient precision, poor data reliability and the like of the traditional single monitoring technology under the complex geological condition of the high dam, the system is characterized in that the system is designed through the cooperative arrangement of a water pipe type settlement meter, a vibrating wire type settlement meter, a wide-range displacement meter and an inclinometry settlement pipe in combination with standard installation processes such as RTK slope control, fine sand layered backfilling and metal pipe protection; layered, full-depth and multi-section covering of the dam body is achieved. In data processing, a reference value is determined through continuous stable reading, a temperature correction coefficient is introduced, and a multi-source data cross validation mechanism is established.

Description

Technical Field

[0001] The present invention relates to the technical field of water conservancy engineering and geotechnical engineering, and in particular to a multi-type settlement monitoring system for rockfill dams and a data processing method. Background Art

[0002] Rockfill dam settlement monitoring is crucial in the safety management of water conservancy projects. Its technical application needs to comprehensively consider the project characteristics and monitoring needs. A power station is located in the Sichuan-Tibet section of the upper reaches of the Jinsha River. It is a first-class large (1) type project with a dam height of 167m and a normal water storage level of 2702m. The dam body filling materials are mainly rockfill materials and transition materials, and the compaction degree varies significantly in different areas. The project area is located in a high-altitude and high-seismic intensity environment. The dam body filling volume is large and the filling speed during the construction period is fast (1.53.0m per layer). Traditional single monitoring technology is difficult to cover the settlement monitoring needs of the entire dam body section (such as the sections at the left of the dam at 0+098.00, the left of the dam at 0+005.50, and the right of the dam at 0+100.00) and at different elevations (2532m, 2565m, 2600m, etc.). In addition, the frequency of manual monitoring is low, and it is impossible to capture the dynamic deformation during the filling process in real time.

[0003] Existing monitoring technologies have significant limitations. For example, if a water-tube sedimentation meter uses a temporary observation screen (such as the device inside the 32-hole plug), the data reliability is insufficient due to low scale accuracy (manual reading error ±3mm) and poor stability (liquid level fluctuation ±5mm due to temperature vibration). If a vibrating-wire sedimentation meter is not corrected for temperature effects, changes in liquid density in an environment of 20°C to 40°C can lead to a drift error of ±5mm / year. Traditional trench excavation slope control relies on manual measurement (error ±1%), which can easily cause water and gas pipeline bends and blockages. If the inclination of the incline sedimentation tube drilling is not strictly controlled (e.g., >1%), it will affect the accuracy of the magnetic ring elevation measurement. In addition, the independent processing of multi-source data lacks a cross-validation mechanism, which may lead to the omission of abnormal data. For example, when a measuring point causes data anomalies due to pipeline damage, traditional methods are difficult to quickly identify.

[0004] This technology breaks through the above bottlenecks through a multi-type instrument collaborative monitoring system. Water pipe sedimentation meters are deployed at different elevations in multiple sections, and RTK is used to control the trench excavation slope in real time (error ±0.5%). Fine sand is backfilled to a thickness of 3050cm and compacted layer by layer (dry density ≥1.65g / cm 3), the pipeline is protected by Q235B galvanized steel pipe, and the inner diameter of the connecting sleeve is 2050mm larger than the main pipe diameter; the vibrating wire settlement meter is fixed to the liquid level monitoring tank through the settlement plate, and the injection pressure is controlled at 0.030.1MPa. The liquid is an antifreeze and corrosion-resistant inert medium (such as ethylene glycol antifreeze), and a temperature correction factor is introduced (laboratory calibration period ≤ 6 months); a large-scale displacement meter is connected with the filling and the verticality is checked (deviation ≤ 0.5°), and the total thickness of the fine material and transition material backfilled around the measuring point is ≥ 80cm; the inclined settlement pipe is buried vertically in the dam body, and the settlement magnetic ring is fixed by cement bentonite. The distance between the magnetic ring and the pipe joint is ≥ 1.2 times the outer diameter of the pipe to ensure the accuracy of full-section settlement monitoring.

[0005] At the data processing level, this technology establishes a standardized process and multi-source verification mechanism. The water tube sedimentation meter uses the average value of the stable liquid level readings for three consecutive days (error ≤±2mm) as the benchmark value. The cumulative settlement is calculated by the "zero-scale elevation liquid level reading of the probe connecting pipe elevation observation screen", where the connecting pipe elevation needs to deduct the distance constant between the probe height and the top of the water inlet pipe; the cumulative settlement of the vibrating wire sedimentation meter is calculated by combining the installation elevation, the zero-scale elevation of the liquid storage tank, the height of the hydraulic pressure liquid column and the liquid level reading difference, and introducing a temperature correction value; the inclined sedimentation tube uses the magnetic ring at the bottom of the hole as the benchmark, and the absolute elevation is recursively deduced by the length of the interval between adjacent magnetic rings. At the same time, it is required to re-measure when the difference in data from different instruments on adjacent sections is greater than 15%, and to check for deviations when the trend consistency with the stratified sedimentation instrument data of the Institute of Water Science is less than 85%, to ensure data credibility.

[0006] In one power station application, this technology achieved full coverage of settlement monitoring during the construction period. For example, the maximum cumulative settlement of a water-tube settlement meter at an elevation of 2565m was 813mm (measurement point VSA2126), the maximum cumulative settlement of a vibrating-wire settlement meter at an elevation of 2532m was 865.94mm (measurement point VVA218), and the maximum cumulative settlement of an inclined settlement tube (ESA22331 magnetic ring) was 527mm, with a data agreement of 92%. Through automated data collection and intelligent early warning (with a monthly change warning threshold of 3080mm / month), the abnormal response time has been shortened to within 2 hours. Furthermore, standardized material selection (such as C20 concrete abutments and Q235B steel pipes) has improved the reliability of the equipment in extreme environments, providing accurate data support for rockfill dam safety assessments and promoting the upgrade of monitoring technology from manual discrete models to intelligent holographic models. Summary of the Invention

[0007] The technical problem to be solved by the present invention is a multi-type settlement monitoring system and processing method for rockfill dams. The system solves a series of technical problems in monitoring installation, data collection and processing during multi-type settlement monitoring based on multiple modules.

[0008] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0009] A multi-type settlement monitoring system and treatment method for rockfill dams, characterized in that the system includes the following monitoring modules that cooperate with each other:

[0010] Water pipe settlement meter modules: Deployed at different elevations across multiple monitoring sections, they achieve high-precision monitoring of layered settlement through trench excavation, fine sand backfill, and metal protection piping, combined with RTK slope control and total station elevation stakeout. The trench excavation depth is controlled according to the designed slope, with the actual excavation depth being 10%-15% of the design value. The backfilled fine sand is 30-50 cm thick, with a dry density of no less than 1.65 g / cm³ after compaction. The piping is constructed of metal pipes with a compressive strength no less than Q235B grade. The inner diameter of the connecting sleeve is 20-50 mm larger than the main pipe diameter, and the length is no less than 1.5 times the main pipe diameter.

[0011] Vibrating Wire Sedimentation Meter Module: This module is installed at a specified elevation on a specific section. The module is secured by a settling pan, monitors the liquid level in a reservoir, and is filled with inert liquid. The module then calculates the cumulative settlement using sensor calibration parameters. The reservoir is installed at an elevation between 60% and 80% of the sensor's effective range, with a filling pressure of 0.03-0.1 MPa. The liquid is an inert medium that is resistant to freezing and corrosion.

[0012] Large-range displacement meter module: Protective pipes are buried through drilling, and pipes are added as filling is completed and verticality is checked to monitor settlement and deformation at different elevations. The diameter of the drilled hole is 50-100 mm larger than the outer diameter of the protective pipe. The total thickness of the backfill of fine material and transition material around the measuring point is not less than 80 cm, and the compaction degree is not less than 95%.

[0013] Inclinometer settlement tube module: vertically buried in the dam body, combined with settlement magnetic rings and electromagnetic settlement meters, calculates absolute elevation changes based on the spacing between adjacent magnetic rings. The settlement magnetic rings are fixed with a bonding material including but not limited to cement bentonite and epoxy resin, and the spacing between the settlement magnetic rings and the pipe joints is no less than 1.2 times the outer diameter of the pipe.

[0014] Multi-source settlement data intelligent processing module: This module realizes intelligent processing and analysis of monitoring data through the following methods:

[0015] A1 Data Purification Processing Mechanism: A dynamic data purification model based on statistical characteristics is constructed to address issues including but not limited to water tube sedimentation meter liquid level fluctuations, abnormal sensor jumps in vibrating wire sedimentation meter, and abnormal data on the magnetic ring of inclinometer sedimentation tubes. The model first collects historical data from monitoring instruments, calculates statistical quantities such as the mean, standard deviation, and percentile of each type of data, and determines the normal fluctuation range of the data. For monitoring data collected in real time, if the difference between the data at a certain time and the data at adjacent times exceeds the reasonable fluctuation range derived from historical statistics, or if the data point significantly deviates from the overall data distribution characteristics, it is determined to be abnormal data. The abnormal data is corrected using the adjacent effective value interpolation method and trend extrapolation method to ensure the reliability and consistency of the data entering subsequent calculations, and the data anomaly rate is controlled within 0.5%.

[0016] A2 settlement intelligent correction algorithm: a multi-factor correction model is introduced when calculating the cumulative settlement of various instruments; for water-tube settlement meters, in addition to integrating direct measurement parameters such as bottom plate elevation and probe structural parameters, the model also incorporates engineering parameters such as but not limited to the compression modulus of the dam filling material, the thickness of the filling layer, and the settlement correlation value of the surrounding measuring points. By establishing a multivariate linear correction equation, the calculation results of the traditional formula are dynamically calibrated, and the correction coefficient is obtained by fitting the historical monitoring data of the same section; for vibrating wire settlement meters, an iterative optimization strategy is used to process the liquid pressure liquid column height and temperature correction value: first, a preliminary calculation is performed based on the sensor calibration parameters, and then the calculation results are iteratively adjusted for multiple rounds by comparing the synchronous data of adjacent measuring points until the difference is less than 0.5mm for three consecutive iterations, ensuring that the error of the liquid pressure parameter after temperature correction is controlled within ±1.2mm;

[0017] A3 Correlation Analysis and Trend Warning Method: Construct a multi-dimensional correlation analysis model for monitoring data, calculate the correlation between settlement data of adjacent sections of different types of monitoring instruments, including but not limited to water pipe and vibrating wire types, displacement meters and inclinometers; the correlation calculation comprehensively considers but not limited to data fluctuation trends, peak occurrence time, and change rate characteristics. When the correlation is lower than the preset threshold, the multi-instrument cross-retest process is automatically triggered to check whether there are abnormal working conditions including but not limited to local voids and pipeline damage; at the same time, based on the time series dynamic prediction model, the settlement change trend is modeled and analyzed: the model uses sliding window technology to dynamically update the prediction parameters according to the periodicity and trend characteristics of the historical data series, and generates the settlement prediction range for the next 7 days in real time; when the actual monitoring data exceeds the upper limit of the prediction range, the system automatically issues a "yellow, orange, red" three-level warning signal, and simultaneously locates the position of the abnormal measuring point, shortening the abnormal response time to within 1 hour, effectively improving the intelligent warning capability of dam settlement.

[0018] As a preferred technical solution of the present invention, the measuring point of the water tube type settlement meter is fixed with a prefabricated concrete base, the strength grade of the base is not less than C15, and the horizontal error of the measuring head is adjusted by a screw to not exceed ±0.5 mm / m.

[0019] As a preferred technical solution of the present invention, the sensor of the vibrating wire sedimentation instrument is sealed with a metal protective cover after being assembled with the sedimentation plate. The thickness of the protective cover is not less than 3 mm and the anti-crushing strength is not less than 100 kPa.

[0020] As a preferred technical solution of the present invention, the observation frequency of the large-scale displacement meter is 12 times / day in the initial stage of installation, 12 times / week after stabilization, and increased to once a day during the peak filling period.

[0021] 5. A multi-type settlement monitoring system and processing method for rockfill dams according to claim 1, characterized in that the inclination of the drilling of the inclinometer settlement tube does not exceed 1%, and the error of the hole depth and hole diameter detected after the hole is drilled does not exceed ±5 cm.

[0022] As a preferred technical solution of the present invention, the processing method comprises the following steps:

[0023] Determination of reference value: For water tube sedimentation meter, the liquid level data is read for 3 consecutive days with an error of no more than ±3 mm, and the average value is taken as the reference value; for vibrating wire sedimentation meter, the average value of the stable readings for 2 consecutive days after the liquid storage tank is filled with liquid for debugging is taken as the reference value;

[0024] Calculation of cumulative settlement:

[0025] Water tube sedimentation meter: The accumulated settlement is equal to the elevation of the connecting pipe of the settlement probe minus the zero scale elevation of the observation screen minus the liquid level reading, where the connecting pipe elevation is the bottom plate elevation plus the probe height minus the distance constant from the top of the water inlet pipe;

[0026] Vibrating Wire Sedimentometer: Cumulative settlement is equal to the installation elevation minus the zero-scale elevation of the reservoir plus the height of the hydraulic pressure column plus the difference in liquid level readings. The height of the hydraulic pressure column is calculated based on the sensor reading and calibration parameters, and a temperature correction is introduced. The temperature correction value is calculated by the sensor temperature correction coefficient and the difference between the current temperature and the reference temperature.

[0027] Inclinometer settlement tube: The accumulated settlement is equal to the current magnetic ring elevation minus the initial magnetic ring elevation. The magnetic ring elevation is recursively calculated through the hole bottom reference ring.

[0028] Data verification and analysis: Compare data from different types of instruments on adjacent sections, and retest when the difference exceeds 15%; simultaneously analyze data from the stratified sedimentation instrument of the Institute of Water Science and Technology, and investigate deviations when the trend consistency is less than 85%.

[0029] As a preferred technical solution of the present invention, the measurement accuracy of the total station is ±0.5 seconds for angle and ±(0.6 mm + 1 ppm) for distance, the measurement error of the observation room floor elevation does not exceed ±10 mm, and the steel ruler accuracy does not exceed ±2 mm.

[0030] As a preferred technical solution of the present invention, the temperature correction value of the vibrating wire sedimentation instrument is the product of the sensor temperature correction coefficient and the difference between the current temperature and the reference temperature, wherein the temperature correction coefficient is obtained by calibration in a laboratory constant temperature chamber, and the calibration period does not exceed 6 months.

[0031] As a preferred technical solution of the present invention, a comprehensive analysis model of multi-source data is established to integrate settlement, monthly change and fill elevation data to generate a settlement time curve with a confidence interval. The monthly change warning threshold is set based on actual data.

[0032] The beneficial effects of adopting this technical solution include: Collaborative monitoring using multiple instruments, including water-tube settlement gauges, vibrating-wire settlement gauges, large-range displacement gauges, and inclinometer settlement tubes, achieves "layered, full-depth, and multi-section" coverage of the dam body. The maximum cumulative settlement near the dam axis was captured at 865.94 mm, 40%-60% higher than the upstream and downstream sides, with a data consistency of 92%. Standardized installation processes and data processing systems ensure monitoring accuracy of ±3 mm, with system errors controlled within ±5 mm. During construction, large-range displacement gauges were used to track fill deformation in real time, with temporary devices set to a ≤3-month switching cycle to avoid error accumulation. Standardized materials enhance the equipment's resistance to extreme environments, while automated data collection and intelligent early warning shorten the response time to abnormalities to within two hours, reducing labor costs by 30% and equipment costs by approximately 20%. The "Guidelines for Multi-Type Settlement Monitoring of Rockfill Dams" have been developed to promote industry standardization and provide accurate data support for dam safety assessments throughout their lifecycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 : Water pipe layout diagram;

[0034] Figure 2 : Trench excavation slope control Figure 1 ;

[0035] Figure 3 : Trench excavation slope control Figure 2 ;

[0036] Figure 4 : Trench excavation slope control Figure 3 ;

[0037] Figure 5 : Trench excavation slope control Figure 4 ;

[0038] Figure 6 : Trench excavation slope control Figure 5 ;

[0039] Figure 7 : Measuring point elevation measurement map;

[0040] Figure 8 : Sedimentation time curve;

[0041] Figure 9 : Vibrating wire measuring point diagram;

[0042] Figure 10 : Liquid tank filling diagram;

[0043] Figure 11 : Displacement time curve of dam vibrating wire settlement instrument;

[0044] Figure 12 :Inclinometer tube settlement curve Figure 1 ;

[0045] Figure 13 :Inclinometer tube settlement curve Figure 2 ;

[0046] Figure 14 :Inclinometer tube settlement curve Figure 3 ;

[0047] Figure 15 :Inclinometer tube settlement curve Figure 4 . DETAILED DESCRIPTION

[0048] The principles of the present disclosure will now be described with reference to several exemplary embodiments shown in the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that these embodiments are only described to facilitate those skilled in the art to better understand and implement the present disclosure, and are not intended to limit the scope of the present disclosure in any way.

[0049] In the following description of the embodiments, specific details such as specific system structures and technologies are provided for illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, and methods are omitted to avoid obscuring the description of the present application with unnecessary details.

[0050] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, components.

[0051] Example 1: Full-process application of a water-tube settlement meter at the dam left section 0+005.50 at an elevation of 2565m

[0052] 1. Monitoring layout and process details

[0053] Distribution of measuring points: Located at the 0+005.50 section on the left side of the dam at an elevation of 2565m, there are 9 measuring points (VSA2121 to VSA2129). A double-pipe design is adopted. The water and gas pipelines are protected by φ80 galvanized steel pipes, and the joints are sealed with φ110 welded pipes (60cm long).

[0054] Reference Attachment Figure 1 , showing the measuring point pile numbers (such as dam 0210.0 to dam 0+196.5) and the location distribution of the elevation 2565m, and the pipeline is fan-shaped along the dam axis.

[0055] 2. Installation process and quality control

[0056] Trench excavation:

[0057] After filling to an elevation of 2565.8m, a trench was excavated with a width of 4m. The actual depth was controlled by the designed slope + 0.4m (designed slope 0.5% to 1%). RTK was used to monitor the slope in real time with an error of ±0.5%.

[0058] Reference Attachment Figure 2-3 , showing that the slope of the trench bottom is consistent with the design according to the on-site measurement of RTK equipment.

[0059] Backfill and pipeline laying:

[0060] First, backfill 40cm of fine sand (particle size ≤ 2mm, mud content ≤ 3%), roll it mechanically for 3 times, and use RTK to monitor the elevation error of ±2cm. Then lay the pipeline and fix it, using φ130 welded pipe to protect the joint.

[0061] Reference Attachment Figure 4-6 , showing the trench profile after backfill and compaction, with the pipeline laid in the center.

[0062] 3. Measuring point installation and elevation calibration

[0063] Probe fixation:

[0064] Use prefabricated C20 concrete base (500mm 3 )Fix the settlement probe and adjust the levelness by screw. The bubble centering error is ≤±0.5mm / m. Use total station (TM50, accuracy ±0.5”+±0.6mm+1ppm) to measure the base plate elevation. For example, the base plate elevation of VSA2121 is 2564.9977m.

[0065] Reference Attachment Figure 7 , showing the measured data of the total station (east coordinate Y: 504214.6064m, north coordinate X: 3329495.8227m, elevation: 2564.9977m).

[0066] 4. Data processing and results

[0067] Determination of the benchmark value: Water and air will be continuously passed from November 2 to 6, 2024. After the liquid level stabilizes on November 6, the average value of three readings (error ±2mm) will be taken as the benchmark value.

[0068] Cumulative settlement calculation:

[0069] Formula: Cumulative settlement = settlement probe connecting pipe elevation (bottom plate elevation + 445mm20mm) observation screen zero scale elevation (2564.017m) liquid level reading

[0070] Example: The bottom plate elevation of VSA2126 measuring point is 2564.5413m, the current liquid level reading is 145mm, and the accumulated settlement = (2564.5413+0.4450.02)2564.0170.145=0.813m (813mm).

[0071] Reference Attachment Figure 8 , showing that the cumulative settlement of the VSA2126 measuring point from November 2024 to March 2025 was 813 mm, with a monthly change of 1447 mm, which is consistent with the law of "large settlement in the middle" of rockfill dams.

[0072] Example 2: Deep monitoring of the vibrating wire settlement meter at the elevation of 2532m on the A21A21 section

[0073] 1. Layout and installation process

[0074] Measuring point distribution: Located at the 0+005.50 section on the left side of the dam at an elevation of 2532m, with 12 measuring points from upstream to downstream (VVA211 to VVA2112). The pipeline is introduced into the liquid storage tank inside the ③2 branch hole plug.

[0075] Reference Attachment Figure 9 , showing that the measuring points are distributed along the axis of the dam, with a spacing of about 50m.

[0076] 2. Key installation steps

[0077] Trench excavation and backfilling:

[0078] After filling to an elevation of 2532.8m, ditches were excavated to 2531.6m, and 40cm of fine sand was backfilled to 2532.0m. The RTK controlled elevation error was ±3cm, and the mechanical static rolling compaction degree was ≥95%.

[0079] Reference Attachment Figure 2-6 , showing that the trench is backfilled with fine sand in layers, and the surface is flat after compaction.

[0080] Sensor fixing:

[0081] After the sensor and the sedimentation plate are assembled, they are fixed with a 3mm thick stainless steel protective cover, and the surrounding area is backfilled with 50cm of fine sand + 50cm of transition material and compacted layer by layer.

[0082] Reference Attachment Figure 9 , showing the protective cover wrapped around the sensor, and the base iron plate connected to the settlement plate with bolts.

[0083] 3. Liquid storage tank debugging and data processing

[0084] Injection and pressure control:

[0085] The installation elevation of the liquid storage tank is 2533.883m (sensor range 70%), and 35℃ ethylene glycol antifreeze is injected. The nitrogen bottle is pressurized to 0.05MPa to eliminate bubbles, and the liquid level is stabilized at 1 / 2 full scale.

[0086] Reference Attachment Figure 10 , showing the nitrogen cylinder connecting pipeline, the pressure gauge reading is 0.05MPa.

[0087] Temperature correction and results:

[0088] Temperature correction coefficient k_T = 0.001660m / °C (VVA212 measuring point), current temperature 11.1°C, reference temperature 16.3°C, correction value = 0.001660×(11.116.3) = 0.008632m.

[0089] Cumulative settlement = 2532.0563 (2533.8832.1457) + (7888) × 0.0010.0086 = 0.263 m (263 mm).

[0090] Reference Attachment Figure 11 , showing that the cumulative settlement of VVA218 measuring point is 865.94mm, with a monthly change of 9.08mm, which grows synchronously with the fill elevation curve.

[0091] Example 3: Full-depth monitoring of the inclinometer settlement pipe at the 0+019.5 section on the left side of the dam

[0092] 1. Drilling and magnetic ring installation

[0093] Drilling construction:

[0094] Drill vertically to the foundation surface (elevation 2475m), the hole diameter is 80mm larger than the outer diameter of the protective tube, the casing wall protection technology is adopted, the hole slope is 0.8% (≤1%), and the hole depth error of the final hole detection is +3cm.

[0095] Magnetic ring fixation:

[0096] The settling magnetic ring is fixed to the hole wall via cement bentonite, with a spacing of 1.0 m (≥1.2 times the outer diameter of the pipe) from the conduit joint. The mechanical claws are tied with paper rope to ensure close contact, and the magnetic ring at the bottom of the hole serves as a reference ring. The display shows that the magnetic ring mechanical claws are in contact with the hole wall after they are released, and the grouting pipe is lowered simultaneously.

[0097] 2. Data Collection and Calculation

[0098] Baseline measurement:

[0099] On July 7, 2023, the initial measurement elevation of the magnetic ring at the bottom of the hole was 2475.595m, and the initial elevation of the ESA22124 magnetic ring was 2526.296m.

[0100] Cumulative settlement calculation:

[0101] Formula: Cumulative settlement = current magnetic ring absolute elevation / initial magnetic ring absolute elevation

[0102] Example: On March 21, 2025, the absolute elevation of the ESA22124 magnetic ring was 2526.296m523mm=2525.773m, and the accumulated settlement was 2525.7732526.296=0.523m (523mm, settlement downward is negative).

[0103] Reference Attachment Figure 12-15 , which shows that the settlement of each magnetic ring in ESA221 hole increases with time, and the settlement of the magnetic ring near the dam axis (such as 24) is the largest, which conforms to the law of "large in the middle and small above and below".

[0104] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A multi-type settlement monitoring system and treatment method for rockfill dams, characterized in that: The system includes the following monitoring modules that work together: Water pipe settlement meter modules: Deployed at different elevations across multiple monitoring sections, they achieve high-precision monitoring of layered settlement through trench excavation, fine sand backfill, and metal protection piping, combined with RTK slope control and total station elevation stakeout. The trench excavation depth is controlled according to the designed slope, with the actual excavation depth being 10%-15% of the design value. The backfilled fine sand is 30-50 cm thick, with a dry density of no less than 1.65 g / cm³ after compaction. The piping is constructed of metal pipes with a compressive strength no less than Q235B grade. The inner diameter of the connecting sleeve is 20-50 mm larger than the main pipe diameter, and the length is no less than 1.5 times the main pipe diameter. Vibrating Wire Sedimentation Meter Module: This module is installed at a specified elevation on a specific section. The module is secured by a settling pan, monitors the liquid level in a reservoir, and is filled with inert liquid. The module then calculates the cumulative settlement using sensor calibration parameters. The reservoir is installed at an elevation between 60% and 80% of the sensor's effective range, with a filling pressure of 0.03-0.1 MPa. The liquid is an inert medium that is resistant to freezing and corrosion. Large-range displacement meter module: Protective pipes are buried through drilling, and pipes are added as filling is completed and verticality is checked to monitor settlement and deformation at different elevations. The diameter of the drilled hole is 50-100 mm larger than the outer diameter of the protective pipe. The total thickness of the backfill of fine material and transition material around the measuring point is not less than 80 cm, and the compaction degree is not less than 95%. Inclinometer settlement tube module: vertically buried in the dam body, combined with settlement magnetic rings and electromagnetic settlement meters, calculates absolute elevation changes based on the spacing between adjacent magnetic rings. The settlement magnetic rings are fixed with a bonding material including but not limited to cement bentonite and epoxy resin, and the spacing between the settlement magnetic rings and the pipe joints is no less than 1.2 times the outer diameter of the pipe. Multi-source settlement data intelligent processing module: This module realizes intelligent processing and analysis of monitoring data through the following methods: A1 Data Purification Processing Mechanism: A dynamic data purification model based on statistical features is constructed to address issues including but not limited to water tube sedimentation meter liquid level fluctuations, vibrating wire sedimentation meter sensor abnormal jumps, and inclinometer sedimentation tube magnetic ring data anomalies. This model first collects historical data from monitoring instruments, calculates statistical quantities such as the mean, standard deviation, and percentile for each type of data, and determines the normal fluctuation range of the data. For real-time monitoring data, if the difference between the data at a certain time and the data at adjacent times exceeds the reasonable fluctuation range determined by historical statistics, or if the data point significantly deviates from the overall data distribution characteristics, it is determined to be abnormal data. Abnormal data are corrected using adjacent effective value interpolation and trend extrapolation methods to ensure the reliability and consistency of data used in subsequent calculations, and to control the data anomaly rate within 0.5%; A2 settlement intelligent correction algorithm: a multi-factor correction model is introduced when calculating the cumulative settlement of various instruments; for water-tube settlement meters, in addition to integrating direct measurement parameters such as bottom plate elevation and probe structural parameters, the model also incorporates engineering parameters such as but not limited to the compression modulus of the dam filling material, the thickness of the filling layer, and the settlement correlation value of the surrounding measuring points. By establishing a multivariate linear correction equation, the calculation results of the traditional formula are dynamically calibrated, and the correction coefficient is obtained by fitting the historical monitoring data of the same section; for vibrating wire settlement meters, an iterative optimization strategy is used to process the liquid pressure liquid column height and temperature correction value: first, a preliminary calculation is performed based on the sensor calibration parameters, and then the calculation results are iteratively adjusted for multiple rounds by comparing the synchronous data of adjacent measuring points until the difference is less than 0.5mm for three consecutive iterations, ensuring that the error of the liquid pressure parameter after temperature correction is controlled within ±1.2mm; A3 Correlation Analysis and Trend Warning Method: Construct a multi-dimensional correlation analysis model for monitoring data, calculate the correlation between settlement data of adjacent sections of different types of monitoring instruments, including but not limited to water pipe and vibrating wire types, displacement meters and inclinometers; the correlation calculation comprehensively considers but not limited to data fluctuation trends, peak occurrence time, and change rate characteristics. When the correlation is lower than the preset threshold, a multi-instrument cross-retest process is automatically triggered to check for abnormal working conditions including but not limited to local voids and pipeline damage; at the same time, based on the time series dynamic prediction model, the settlement change trend is modeled and analyzed: the model uses sliding window technology to dynamically update the prediction parameters based on the periodicity and trend characteristics of the historical data series, and generates a settlement prediction range for the next 7 days in real time; when the actual monitoring data exceeds the upper limit of the prediction range, the system automatically issues a "yellow, orange, red" three-level warning signal, and simultaneously locates the position of the abnormal measuring point, shortening the abnormal response time to within 1 hour, effectively improving the intelligent early warning capability of dam settlement.

2. A multi-type settlement monitoring system and treatment method for rockfill dams according to claim 1, characterized in that: The measuring point of the water tube type settlement meter is fixed with a prefabricated concrete base, the strength grade of the base is not less than C15, and the horizontal error of the measuring head is adjusted by a screw to not exceed ±0.5 mm / m.

3. A multi-type settlement monitoring system and treatment method for rockfill dams according to claim 1, characterized in that: The sensor of the vibrating wire sedimentation instrument is assembled with the sedimentation plate and sealed with a metal protective cover. The thickness of the protective cover is not less than 3 mm and the anti-rolling strength is not less than 100 kPa.

4. A multi-type settlement monitoring system and treatment method for rockfill dams according to claim 1, characterized in that: The observation frequency of the large-scale displacement meter is 12 times / day in the initial stage of installation, 12 times / week after stabilization, and increased to once a day during the peak filling period.

5. The multi-type settlement monitoring system and treatment method for rockfill dams according to claim 1 is characterized in that: The inclination of the drilling of the inclinometer settlement tube does not exceed 1%, and the error of the hole depth and hole diameter detected after the hole is formed does not exceed ±5 cm.

6. A multi-type settlement monitoring system and treatment method for rockfill dams according to claim 1, characterized in that: The processing method comprises the following steps: Determination of reference value: For water tube sedimentation meter, the liquid level data is read for 3 consecutive days with an error of no more than ±3 mm, and the average value is taken as the reference value; for vibrating wire sedimentation meter, the average value of the stable readings for 2 consecutive days after the liquid storage tank is filled with liquid for debugging is taken as the reference value; Calculation of cumulative settlement: Water tube sedimentation meter: The accumulated settlement is equal to the elevation of the connecting pipe of the settlement probe minus the zero scale elevation of the observation screen minus the liquid level reading, where the connecting pipe elevation is the bottom plate elevation plus the probe height minus the distance constant from the top of the water inlet pipe; Vibrating Wire Sedimentometer: Cumulative settlement is equal to the installation elevation minus the zero-scale elevation of the reservoir plus the height of the hydraulic pressure column plus the difference in liquid level readings. The height of the hydraulic pressure column is calculated based on the sensor reading and calibration parameters, and a temperature correction is introduced. The temperature correction value is calculated by the sensor temperature correction coefficient and the difference between the current temperature and the reference temperature. Inclinometer settlement tube: The accumulated settlement is equal to the current magnetic ring elevation minus the initial magnetic ring elevation. The magnetic ring elevation is recursively calculated through the hole bottom reference ring. Data verification and analysis: Compare data from different types of instruments on adjacent sections, and retest when the difference exceeds 15%; simultaneously analyze data from the stratified sedimentation instrument of the Institute of Water Science and Technology, and investigate deviations when the trend consistency is less than 85%.

7. A multi-type settlement monitoring system and treatment method for rockfill dams according to claims 1 and 6, characterized in that: The measurement accuracy of the total station is ±0.5 seconds for angle and ±(0.6 mm + 1 ppm) for distance. The measurement error of the observation room floor elevation does not exceed ±10 mm, and the accuracy of the steel ruler does not exceed ±2 mm.

8. A multi-type settlement monitoring system and treatment method for rockfill dams according to claims 1 and 6, characterized in that: The temperature correction value of the vibrating wire sedimentation instrument is the product of the sensor temperature correction coefficient and the difference between the current temperature and the reference temperature. The temperature correction coefficient is obtained by calibration in a laboratory constant temperature chamber, and the calibration period does not exceed 6 months.

9. A multi-type settlement monitoring system and treatment method for rockfill dams according to claims 1 and 6, characterized in that: A comprehensive analysis model of multi-source data is established to integrate settlement, monthly change and fill elevation data to generate a settlement time curve with a confidence interval. The monthly change warning threshold is set based on actual data.

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