Safety monitoring method of concrete faced rockfill dam and water pipe type settlement meter adopted by safety monitoring method

Abstract

The invention discloses a safety monitoring method for a concrete faced rockfill dam. The method comprises the following steps: determining a monitoring point position of a concrete faced rockfill dam engineering safety monitoring system; internet-of-things sensing facilities are installed at the monitoring point position and the preset position of the concrete faced rockfill dam project; the internet-of-things sensing facility is connected with the safety monitoring system through matched hardware and software interfaces; and the safety monitoring system outputs corresponding early warning information based on a comparison result of the proposed early warning index, the historical extreme value and the monitoring value of the monitoring point position Internet of Things sensing facility. According to the safety monitoring method, the whole process of the overall states of various buildings can be continuously monitored, abnormal signs of the hydraulic structures caused by property variation can be found in time, and corresponding early warning information is sent out so that measures can be taken in time, major accidents can be prevented or avoided, and the safety risk of engineering can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of safety monitoring of dam bodies, and in particular to a safety monitoring method for a face rockfill dam and a water tube type settlement instrument used therein. Background Art

[0002] Reservoir hubs are mainly composed of buildings such as dams, spillways, spillway tunnels, water diversion systems, powerhouses, and switch stations. Concrete face rockfill dams are a type of dam commonly used in water conservancy and hydropower projects. In order to understand the operation status of the project and monitor the safety status of each building, it is necessary to monitor external deformation, internal deformation, joint deformation, stress strain, temperature, seepage, environmental quantities, etc. in dams, powerhouses, spillways, etc. The existing monitoring methods need to be combined with manual work, which is labor-intensive and has low monitoring accuracy. Summary of the invention

[0003] In view of the above shortcomings, the object of the present invention is to provide a safety monitoring method for a concrete face rockfill dam with automatic monitoring; the object of the present invention is also to provide a water tube settlement instrument used in the above safety monitoring method:

[0004] To this end, a safety monitoring method for a panel rockfill dam of the present invention comprises determining monitoring points of a safety monitoring system for a panel rockfill dam project; installing Internet of Things sensing facilities at the monitoring points and predetermined positions of the panel rockfill dam project; the Internet of Things sensing facilities are connected to the safety monitoring system through matching hardware and software interfaces; the safety monitoring system outputs corresponding warning information based on the comparison results of the proposed warning indicators, historical extreme values ​​and the monitoring values ​​of the Internet of Things sensing facilities at the monitoring points.

[0005] Furthermore, the IoT sensing facilities include at least one of a total station robot automatic monitoring system for monitoring the external horizontal displacement of the dam body, a GNSS automatic monitoring system for monitoring the surface displacement of the project, a water tube settlement meter for monitoring the vertical displacement, and a steel wire displacement meter for measuring the internal horizontal displacement.

[0006] Furthermore, the total station robot automatic monitoring system includes an observation room and an observation point. The total station robot is arranged in the observation room. An observation pier and a prism are arranged on the observation point. Real-time data collection, transmission and release are realized through a multi-sensor automatic monitoring system.

[0007] Furthermore, the GNSS automatic monitoring system includes a base station and a mobile station. The base station includes a GNSS receiver, and the mobile station includes multiple GNSS receivers. After the base station and the mobile station GNSS receive differential data, the GNSS monitoring method is used to perform real-time automatic monitoring of the dam surface displacement.

[0008] Furthermore, the automatic monitoring system of the water tube sedimentation meter consists of a measuring and controlling device, a water tube sedimentation meter control device, an observation cabinet and a connecting pipe. The automatic control device of the water tube sedimentation meter receives control commands from the measuring and controlling device in the safety monitoring system to automatically add water, stabilize delay, automatically search for the water surface, and measure the water level.

[0009] Furthermore, the steel wire displacement meter includes a tension wire horizontal displacement meter and a displacement sensor, and the displacement sensor is arranged on the steel wire of the measuring section at the loading end.

[0010] Furthermore, the methods for formulating the early warning indicators include: 1. Design specification method, which is to compare the actual measured values ​​of dam safety monitoring with the following monitoring indicators to evaluate and analyze the safety of dam operation; 1) compare with multiple measured values ​​under the same conditions in history; 2) compare with the maximum and minimum values ​​in history; 3) compare with the results of design, calculation, and model tests; 4) compare with dam safety control indicators; 5) compare with forecast prediction values; 2. Typical small probability method, for measuring points with no obvious trend changes in measured values ​​and that meet the normal distribution test, the typical small probability method is used to formulate early warning indicators, and the monitoring values ​​at the significance level of 1% are used as the proposed early warning indicators; 3. Confidence interval estimation method, which selects effective measuring points, and adopts the confidence interval estimation method to formulate early warning indicators, and the monitoring values ​​at the significance level of 1% are used as the proposed early warning indicators.

[0011] Furthermore, the early warning mode of the safety monitoring system includes that if the monitoring value of the measuring point does not exceed the judgment threshold, and the inspection does not find any hidden dangers and lesions that affect safety, the dam is considered to be in a safe operating state; if the monitoring value of the measuring point exceeds the judgment threshold, a "measurement value abnormality reminder" message is issued to the reservoir monitoring personnel, prompting them to conduct encrypted supplementary measurement; if the measured value returns to within the judgment threshold after supplementary measurement, the "measurement value abnormality reminder" message is revoked; if the supplementary measurement value still exceeds the judgment threshold, and the inspection finds hidden dangers and lesions that affect safety, a "dam safety reminder" message is issued, and an expert consultation and review is initiated to determine whether to issue a "dam safety early warning" message; if the inspection does not find any hidden dangers and lesions that affect safety, an evaluation is conducted in combination with the monitoring conditions of adjacent related measuring points; if the measuring point that exceeds the judgment threshold is a "general" monitoring level measuring point, the measurement value of its adjacent "key" monitoring level measuring point is checked, and if the measured value of the "key" monitoring level measuring point exceeds the judgment threshold, a "dam safety reminder" message is issued, and an expert consultation and review is initiated to determine whether to issue a "dam safety early warning" message; If the measured value of the measuring point does not exceed the warning value, a message of "abnormal measured value, strengthen monitoring and inspection" will be sent to the monitoring personnel; if the measuring point exceeding the judgment threshold is a "key" monitoring level measuring point, check the measured values ​​of the adjacent related monitoring measuring points. If the measured value of the related measuring point exceeds the judgment threshold, a "dam safety reminder" message will be sent, and an expert consultation and review will be initiated to determine whether a "dam safety early warning" message will be issued. If the measured value of the related measuring point does not exceed the judgment threshold, check whether there is a trend change in the measured value of the measuring point exceeding the judgment threshold. If there is a trend change, a "dam safety reminder" message will be sent, and an expert consultation and review will be initiated to determine whether a "dam safety early warning" message will be issued; if there is no trend change, a message of "abnormal measured value, strengthen monitoring and inspection" will be sent to the monitoring personnel; for monitoring measuring points that use multiple methods to formulate early warning indicators, when the measured value exceeds the early warning indicator of the confidence interval method, a safety early warning will be issued according to the above steps; when it exceeds the early warning indicator of the standard method or the small probability method, a "dam safety reminder" message will be directly sent after eliminating the measurement error, and an expert consultation and review will be initiated to determine whether a "dam safety early warning" message will be issued.

[0012] The present invention also includes a water tube type sedimentation meter used in the above-mentioned safety monitoring method, including a probe suitable for being set at a monitoring point, the probe including a water inlet pipe, an overflow port for determining the water level is arranged on the water inlet pipe, and the water inlet pipe is provided with an electrical signal device for sending an electrical signal to the system when the water inlet pipe reaches a predetermined water level.

[0013] Furthermore, the electrical signal device includes a fixed electrode and a movable electrode, the movable electrode is arranged on a floating block in a water inlet pipe, and the water inlet pipe used is arranged as follows: including a first pipe section and a second pipe section, the first pipe and the second pipe section are fixedly connected, an overflow port is arranged at the upper end of the first pipe section, a limit block is arranged in the first pipe section or the second pipe section, and the floating block has a step surface that cooperates with the limit block, which is used to lift the floating block when the water inlet pipe has a certain pressure, so that the movable electrode contacts the fixed electrode to send out an electrical signal; or The water inlet pipe includes a first pipe section, a second pipe section and a branch pipe. The first pipe section, the second pipe section and the branch pipe are closed to the internal space of the measuring head. The branch pipe is connected to the overflow port so that the water in the water inlet pipe flows into the branch pipe from the overflow port. The lower end of the branch pipe is connected to the lower end of the first pipe section through a one-way valve. A rigid air inlet pipe is fixed to the upper end of the second pipe section. The air inlet pipe passes through a float block. A limit block is set at the lower end of the air inlet pipe. In this way, when the water level of the water inlet pipe reaches the overflow port, the movable electrode on the float block contacts the fixed electrode.

[0014] The beneficial technical effects of the present invention are:

[0015] The safety monitoring method of the present invention can obtain first-hand information through the IoT sensing facilities at each monitoring point, understand the actual properties of the building and its foundation, and provide necessary information for judging the safety of the project during operation. Through continuous monitoring of the overall status of various types of buildings throughout the process, abnormal signs of hydraulic structures due to property variations can be discovered in time, and corresponding early warning information can be issued to take timely measures to prevent or avoid major accidents and reduce the safety risks of the project. At the same time, according to the monitoring data accumulated over a long period of operation, the operation law of the building can be mastered, and its future properties and development trends can be predicted and forecasted, providing a scientific basis for daily operation and maintenance, scheduling operation, safety status evaluation, reinforcement, emergency management, downgrade and retirement. Safety monitoring is not only one of the important measures to ensure project safety, but also a need for safety management. Improve the design level through verification and optimization of the design. Through the systematic analysis and feedback analysis of the building operation and the long-term accumulated monitoring data, verify whether the original design plan is reasonable, and whether the parameter values, calculation methods, and calculation models of the design calculation are correct. By comparing and analyzing the measured data of the engineering prototype with the engineering characteristic indicators of theoretical calculation, it is easy to grasp the rationality of the engineering design, so that the design scheme and parameters can be improved and the design level can be improved in future hazard removal and reinforcement or demolition and reconstruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a diagram showing the arrangement of the external deformation measuring points of the dam in a specific embodiment;

[0017] Figure 2 It is a monitoring arrangement diagram of the horizontal displacement and vertical displacement inside the dam body in a specific embodiment;

[0018] Figure 3This is a schematic diagram of the installation of the forced centering device;

[0019] Figure 4 This is the installation diagram of the horizontal displacement meter of the tensioning line;

[0020] Figure 5 It is a schematic diagram of a water tube sedimentation instrument;

[0021] Figure 6 is a schematic diagram of a first embodiment of a probe water inlet pipe;

[0022] Figure 7 It is a partial enlarged schematic diagram of the first embodiment;

[0023] Figure 8 is a schematic diagram of a second embodiment of a probe water inlet pipe;

[0024] Fig. 9 This is a schematic diagram of the safety warning mode.

[0025] Explanation of the reference numerals in the accompanying drawings: 1. Observation pier; 2. Lightning rod; 3. Prism; 4. GNSS receiver; 5. Steel wire; 6. Probe; 7. Air inlet pipe; 8. Drain pipe; 9. Water inlet pipe; 901. First pipe section; 902. Second pipe section; 903. Flange; 904. Limit block; 905. Float; 906. Movable electrode; 907. Fixed electrode; 908. Overflow; 909. Branch pipe; 910. Temporary storage box; 911. One-way valve; 10. Measuring tube; 11. Water storage tank; 12. Pressure water tank; 13. Displacement sensor. DETAILED DESCRIPTION

[0026] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0027] Reference Figures 1 to 8 As shown, a safety monitoring method for a panel rockfill dam of the present invention includes determining the monitoring points of the panel rockfill dam engineering safety monitoring system; installing IoT sensing facilities at the monitoring points and predetermined positions of the panel rockfill dam engineering; the IoT sensing facilities are connected to the safety monitoring system through matching hardware and software interfaces; the safety monitoring system outputs corresponding warning information based on the comparison results of the proposed warning indicators, historical extreme values ​​and the monitoring values ​​of the IoT sensing facilities at the monitoring points. The determination of the monitoring points is carried out according to the existing technology, and multiple factors need to be considered, including terrain, geological conditions, construction technology, and monitoring purposes. For example, in view of the displacement changes on the dam surface, monitoring points are set at key locations such as the dam section, foundation, closing section, and places with complex geological conditions, and the structures of the measuring points and base points must be firm and reliable and not easy to deform. Figure 1The figure shows the external deformation monitoring points of the dam set on the reservoir dam body in this embodiment. Figure 2 The internal horizontal displacement and vertical displacement monitoring points set in this embodiment are shown. The IoT sensing facilities include a total station robot automatic monitoring system, a GNSS automatic monitoring system, a water pipe settlement meter, a wire displacement meter, etc. The software interface (or protocol) supporting each IoT sensing facility includes: a total station robot F-MOS processing software, a GNSS Beidou S-MOS processing software, a water pipe settlement meter acquisition module, a wire displacement meter measurement and control module, and an automated instrument acquisition data analysis software. The specific coordination process is that the fixedly arranged sensors modulate the monitoring data into a transmittable signal, select a wireless or wired communication method according to the distance of the transmission and the location, and complete the self-checking and local storage of the data at the data acquisition workstation. And the operation is completed by controlling the parameter configuration and sampling control through the control signal. After the data enters the processing server, the data processing software completes the automatic solution, adjustment and other tasks, and the data analysis and display functions realize the monitoring deformation statistics, and evaluate, compare and warn the data. When data processing is completed, the original data and solution results are stored in the database. The warning information obtained from data analysis, as well as time information, health status, etc. are stored in the database. The database also provides historical monitoring data and other information for the analysis module to call.

[0028] The total station robot automatic monitoring system can realize automatic observation of the prism target point, and use the built-in temperature and pressure sensors of the communication multi-function box to automatically collect the ambient temperature and pressure data in real time. At the same time, the coordinates and temperature and pressure data of the monitoring point can be transmitted to the data center for solution in real time through optical fiber or wireless 4G. The system is mainly composed of a total station, a prism, a communication multi-function box, a communication network and a host computer solution software. The layout of the monitoring points can be found in Figure 1 As shown, in this embodiment, the total station adopts Leica TM60, which has an angle measurement accuracy of 0.5″ and a distance measurement accuracy of 0.6mm+1ppm. The total station robot position construction. The brick-concrete observation room is equipped with an automatic control roller shutter and lightning protection grounding, and a set of monitoring cameras are installed to monitor the safety status and operation status of the total station around the clock. The camera is connected to the existing monitoring platform through an optical fiber network, and a special shutter box, thermometer, and barometer are set. The rear view point also needs to be equipped with a special shutter box, thermometer, and barometer to ensure meteorological correction. Observation points are set at the monitoring points, refer to Figure 3 As shown, it includes an observation pier 1 and a prism 3, and realizes real-time data collection, transmission and release through a multi-sensor automatic monitoring system.

[0029] The GNSS automatic monitoring system includes a base station and a mobile station. The base station includes a GNSS receiver, and the mobile station includes multiple GNSS receivers 4. After the base station and the mobile station GNSS receive differential data, the GNSS monitoring method is used to perform real-time automatic monitoring of the dam surface displacement. Figure 3 As shown, in this embodiment, a forced centering device is installed at the observation point, and a GNSS Beidou facility and a lightning rod 2 are installed without affecting the function of external displacement monitoring of the dam. A total of 31 monitoring stations (mobile stations) are installed, 1 GNSS reference station is installed at the spillway, and a GNSS reference station is installed near the power station, for a total of 2 reference stations.

[0030] The wire displacement meter includes a tension wire horizontal displacement meter and a displacement sensor 13, and the displacement sensor 13 is arranged on the wire 5 of the measuring section at the loading end. Figure 4 As shown, in this embodiment, three monitoring sections are selected inside the rockfill body of the dam perpendicular to the axis of the dam. The displacement sensor has a range of 1000mm. The displacement sensor is a high-precision displacement sensor. One end of the displacement meter is fixed on the measuring frame, and the other end is pulled out and fixed on the cursor through a flexible steel wire. When the steel wire 5 is pulled, the displacement sensor steel wire 5 is pulled outward, and the sensor output changes, thereby measuring the displacement. When the measurement module receives the loading signal, the module starts the loading switch of the loading motor to load all the measuring points of the corresponding observation room. When real-time measurement is performed, the loading is performed manually by operating the acquisition software, and when timed measurement is performed, the loading is automatically controlled by the module. When real-time measurement is performed, the module completes the loading process within about 2 minutes. After the loading is completed, it needs to wait for a period of time, and the measurement is performed after the measured value is stable; when timed measurement is performed, the module waits for about 20 minutes after the loading is completed and the measured value is stabilized before automatic measurement.

[0031] The automatic monitoring system of the water tube sedimentation instrument consists of a measurement and control device, a water tube sedimentation instrument control device, an observation cabinet and a connecting pipe. The automatic control device of the water tube sedimentation instrument receives the control command of the measurement and control device in the safety monitoring system to automatically add water, stabilize the delay, automatically find the water surface, and measure the water level. Figure 5 As shown, the water tube type sedimentation meter automatic monitoring system includes a probe 6 and a measuring tube 10, and may also include a water storage tank 11, a pressure water tank 12 and other devices for automatic water addition, and performs automatic measurement under the control of the control device. Figure 5 and Figure 6 , Figure 7As shown, in Example 1, the probe 6 is improved and still includes an air inlet pipe 7 and a water discharge pipe 8. The air inlet pipe 7 is used to keep the internal air pressure of the probe 6 consistent with the atmospheric pressure. The water inlet pipe 9 includes a first pipe section 901 and a second pipe section 902. The first pipe and the second pipe section 902 are fixedly connected by a flange 903. An overflow port 908 is provided at the upper end of the first pipe section 901. A fixed electrode 907 is provided on the second pipe section 902. A floating block 905 is provided in the second pipe section 902 and a movable electrode 906 cooperating with the fixed electrode 907 is provided above the floating block 905. The fixed electrode 907 and the movable electrode 906 are connected to an external power supply through a wire. A limit block 904 is provided at the upper end of the first pipe section 901. The floating block 905 has a step surface cooperating with the limit block 904 (the longitudinal section of the floating block 905 is T-shaped). Its working principle is as follows: during measurement, under the control of the control device, water of a certain pressure is injected into the water inlet pipe 9, the water level of the water inlet pipe 9 rises, and the float 905 in the water inlet pipe 9 is pushed up, and the contact circuit between the movable electrode 906 and the fixed electrode 907 is turned on to send out an electrical signal. At this time, the water level of the water inlet pipe 9 reaches the overflow port 908, and the float 905 can be made of lightweight foam. The influence of the weight of the float 905 and the movable electrode 906 on the water level of the measuring tube 10 can be considered in the calculation. After the water flows out of the overflow port 908, it is discharged through the drain pipe 8. Of course, the lower surface of the float 905 can also be a predetermined distance from the overflow port. Water with a certain pressure is used to push the float to rise to realize the sending of the electrical signal. After receiving the electrical signal, the water pressure is reduced so that the water flows out of the overflow port stably. After stabilization, the float is out of contact with the water surface. After stabilization, measurement can be carried out, and the water level data is automatically read by the corresponding sensor to measure the settlement value. The conventional probe 6 needs to wait for the drain pipe 8 to drain water before it can determine that the water level in the water inlet pipe 9 has reached the overflow port 908. Compared with the conventional probe 6, the waiting time of the embodiment 1 is shorter. Moreover, due to the influence of irregular settlement, although the drain pipe 8 is tilted, the pipe may be deformed or V-shaped during the irregular settlement process, resulting in drainage difficulties, resulting in a long waiting time or inability to determine the water surface. In order to avoid the situation where the drain pipe 8 fails to drain water and thus damages the probe 6, refer to Figure 8As shown, the water inlet pipe 9 includes a branch pipe 909, which is connected to the overflow port 908, so that the water of the water inlet pipe 9 flows into the branch pipe 909 from the overflow port. The lower end of the branch pipe 909 is connected to the lower end of the water inlet pipe through a one-way valve 911. The upper end of the water inlet pipe is fixed with a rigid air inlet pipe 7, and the rigid air inlet pipe 7 passes through a float 905. A limit block 904 is set at the lower end of the rigid air inlet pipe 7. In this way, when the water level of the water inlet pipe 9 reaches the overflow port, the movable electrode 906 on the float 905 contacts the fixed electrode 907. The working principle of embodiment 2 is basically the same as that of embodiment 1, except that, in embodiment 2, the inlet water no longer flows into the inner cavity of the probe 6 from the overflow port 908 and then is discharged from the drain pipe 8. Embodiment 2 does not need to set the drain pipe 8. After the water level of the inlet pipe 9 rises to reach the overflow port 908, the fixed electrode 907 and the movable electrode 906 are connected to send an electrical signal, and the external water injection is stopped. The water level of the inlet pipe 9 reaches the overflow port 908, and the water exceeding the overflow port 908 enters the branch pipe 909. The branch pipe 9 09 can be connected to a temporary storage box 910. Since the water level in the branch pipe 909 is lower than the overflow port 908, the water pressure in the branch pipe 909 is lower than the water inlet pipe 9, the one-way valve 911 will not open, and the overflow water is stored in the branch pipe 909 and the temporary storage box 910. After the measurement is completed, the water in the water inlet pipe 9 is pumped out, the water level in the water inlet pipe 9 drops, the water pressure in the branch pipe 909 is greater than that in the water inlet pipe 9, the one-way valve 911 in the branch pipe 909 opens, and the water in the branch pipe 909 is drained.

[0032] In the above embodiment, the method for formulating the early warning indicator includes:

[0033] 1. Design specification method, which evaluates and analyzes the safety of dam operation by comparing the measured values ​​of dam safety monitoring with the following monitoring indicators;

[0034] 1) Compare with multiple measurements under the same conditions in history;

[0035] 2) Compare with the maximum and minimum values ​​in history;

[0036] 3) Compare with the design, calculation and model test results;

[0037] 4) Comparison with dam safety control indicators;

[0038] 5) Compare with the forecast value;

[0039] 2. Typical small probability method: For the measurement points with no obvious trend change and conforming to the normal distribution test, the typical small probability method is used to formulate early warning indicators, and the monitoring value when the significance level is 1% is used as the proposed early warning indicator; according to the measured data, each effect size Xmi in the monitoring data sequence of the effective measurement point is selected to obtain the sample interval with the sub-sample number n:

[0040] X={X m1 ,Xm2 ,..., X mn}

[0041] where: Xmi is a random variable.

[0042] Estimate its statistical characteristic values using the following two equations:

[0043]

[0044] Use a statistical test method (such as the K-S method) to conduct a distribution test on it and determine the distribution function F(x) of its probability density f(x)

[0045] (such as normal distribution, lognormal distribution, and extreme value type I distribution, etc.).

[0046] Let Xm be the extreme value of the monitored effect quantity. If the dam is about to show abnormalities or danger when X > Xm, the probability is:

[0047]

[0048] The failure probability Pa (hereinafter referred to as a) is determined according to the importance of the dam. For the Shanxi Reservoir, a can be taken as 1%. After determining a, find Xm = F-1(x, σx, a) from the distribution function of Xm.

[0049] After passing the K-S method test, for the measuring points that follow a normal distribution, the typical small probability method can be used to calculate the warning index. For the measuring points that do not satisfy the normal distribution, the confidence interval estimation method should be used to draw up the warning index.

[0050] III. Confidence interval estimation method. Select the effective measuring points among them and use the confidence interval estimation method to draw up the warning index, taking the monitoring value at a significance level of 1% as the drawn warning index. According to the relevant content of the "Hydraulic Design Manual", select the effective measuring points with higher modeling accuracy among them and use the confidence interval estimation method to draw up the warning index, taking the monitoring value at a significance level of 1% as the drawn warning index.

[0051] First, based on the monitoring data, establish a statistical model between the monitored effect quantity and the influencing factors through the analysis of the influencing factors and factor models; then use the model to calculate the monitored effect quantity under various load actions The difference from the measured value (E) Then there is a probability of 1 - a that this value is within the confidence band (Δ = ±iS). At the same time, the change trend of the measured value is another factor reflecting the quantitative behavior of the dam monitoring. Therefore, under the determined significance level a, the confidence interval (confidence band) and change trend of a statistical model with higher accuracy (generally requiring the multiple correlation coefficient R of the measuring point > 0.8) can be used as the basis for judging the abnormality and safety of the measured value, and the warning index of the corresponding measuring point can be drawn up accordingly.

[0052] According to the actual situation of the Shanxi Reservoir Dam, the significance level α is taken as 1%. When α is 1%, i is approximately equal to 3, that is, Δ = ±3S.

[0053] When | and there is no obvious trend change|, it can be considered that the operation is normal or safe; if there is a trend change, monitoring and analysis should be strengthened to find the reasons.

[0054] When | time|, the measured value is abnormal. If there is no obvious trend change, strengthen monitoring and analysis to find the reasons; if there is an obvious trend change, it is a serious abnormality. Strengthen monitoring and analysis, and while finding the reasons, take appropriate measures. Therefore, the warning indicators for the corresponding monitored quantities are:

[0055]

[0056] m

[0057] Since the warning indicators formulated by the confidence interval method are greatly affected by the measured value sequence and the model accuracy, as time goes by and the monitoring data accumulates continuously, the statistical model fitting the measured value sequence changes with time. Therefore, it is recommended to update the model after 3 - 5 years and re - formulate the warning indicators.

[0058] The method for formulating monitoring indicators can use the multiple correlation coefficient method to verify the results of formulating the indicators of the safety monitoring system.

[0059] The multiple correlation coefficient is an index that measures the degree of linear correlation between one variable and multiple other variables. It cannot be directly calculated and can only be indirectly calculated by certain methods.

[0060] Measure the correlation coefficient between a variable y and multiple other variables x1, x2,..., xk. x1, x2,..., xk cannot be directly calculated.

[0061] It can be considered to construct a linear combination of x1, x2,..., xk, and use the simple correlation coefficient between this linear combination and y

[0062] as the multiple correlation coefficient between variable y and x1, x2,..., xk. The specific process is as follows:

[0063] The first step is to perform a regression of y on x1, x2,..., xk to obtain:

[0064] The second step is to calculate the simple correlation coefficient, which is the multiple correlation coefficient between y and x1, x2,..., xk.

[0065] The calculation formula for the multiple correlation coefficient is:

[0066]

[0067] The proposed monitoring indicators are verified by using the multiple correlation coefficient, that is, the correlation between the historical monitoring data and the proposed early warning indicator model is used for judgment.

[0068] In the above embodiment, referring to Fig. 9 The flow chart shown is based on the proposed early warning indicators and historical extreme values ​​(collectively referred to as assessment thresholds), combined with inspection results, to identify the safety status of the dam and preliminarily determine the dam early warning mode in accordance with the following requirements.

[0069] (1) If the monitoring value at the measuring point does not exceed the assessment threshold and no hidden dangers or lesions that may affect safety are found during the inspection, the dam is considered to be in safe operation.

[0070] (2) If the monitoring value of a measuring point exceeds the assessment threshold, a "measurement value abnormality reminder" message will be sent to the reservoir monitoring personnel, prompting them to conduct additional measurements. If the measured value returns to within the assessment threshold after the supplementary measurement, the "measurement value abnormality reminder" message will be cancelled. If the measured value still exceeds the assessment threshold after the supplementary measurement, and the inspection also finds hidden dangers and lesions that affect safety, a "dam safety reminder" message will be sent, and an expert consultation and review will be initiated to determine whether to issue a "dam safety warning" message; if the inspection does not find hidden dangers and lesions that affect safety, an evaluation will be conducted in combination with the monitoring conditions of nearby related measuring points.

[0071] (3) If the measurement point that exceeds the assessment threshold is a “general” monitoring level measurement point, check the measurement value of its adjacent “key” monitoring level measurement point. If the measurement value of the “key” monitoring level measurement point also exceeds the assessment threshold, issue a “dam safety reminder” message, initiate an expert consultation and review, and determine whether to issue a “dam safety warning” message. If the measurement value of the “key” monitoring level measurement point does not exceed the warning value, issue a “measurement value abnormality, strengthen monitoring and inspection” message to the monitoring personnel.

[0072] (4) If the measurement point that exceeds the judgment threshold is a "key" monitoring level measurement point, check the measurement values ​​of its adjacent related monitoring measurement points. If the measurement value of the related measurement point exceeds the judgment threshold, issue a "dam safety reminder" message, initiate an expert consultation and review, and determine whether to issue a "dam safety warning" message. If the measurement value of the related measurement point does not exceed the judgment threshold, check whether the measurement value of the measurement point that exceeds the judgment threshold has a trend change. If there is a trend change, issue a "dam safety reminder" message, initiate an expert consultation and review, and determine whether to issue a "dam safety warning" message; if there is no trend change, issue a "measurement value abnormality, strengthen monitoring and inspection" message to the monitoring personnel.

[0073] (5) For monitoring points where early warning indicators are formulated using multiple methods, when the measured value exceeds the early warning indicator of the confidence interval method, a safety warning is issued according to the above steps; when it exceeds the early warning indicator of the standard method or the small probability method, a "dam safety reminder" message is directly issued after eliminating the measurement error, and an expert consultation and review is initiated to determine whether to issue a "dam safety warning" message.

[0074] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A safety monitoring method for a concrete face rockfill dam, characterized by: include Determine the monitoring points of the safety monitoring system for the concrete face rockfill dam project; Install IoT sensing facilities at monitoring points and predetermined locations of the concrete face rockfill dam project; The IoT sensing facility is connected to the security monitoring system through supporting hardware and software interfaces; The safety monitoring system outputs corresponding warning information based on the comparison results of the proposed warning indicators, historical extreme values ​​and the monitoring values ​​of the Internet of Things sensing facilities at the monitoring points.

2. A safety monitoring method for a concrete face rockfill dam according to claim 1, characterized in that: The IoT sensing facilities include at least one of a total station robot automatic monitoring system for monitoring the external horizontal displacement of the dam body, a GNSS automatic monitoring system for monitoring the surface displacement of the project, a water tube settlement meter for monitoring the vertical displacement, and a steel wire displacement meter for measuring the internal horizontal displacement.

3. A safety monitoring method for a concrete face rockfill dam according to claim 2, characterized in that: The total station robot automatic monitoring system includes an observation room and an observation point. The total station robot is arranged in the observation room. An observation pier and a prism are arranged on the observation point. Real-time data collection, transmission and release are realized through a multi-sensor automatic monitoring system.

4. The safety monitoring method for a concrete face rockfill dam according to claim 2 is characterized by: The GNSS automatic monitoring system includes a base station and a mobile station. The base station includes a GNSS receiver, and the mobile station includes multiple GNSS receivers. After the base station and the mobile station GNSS receive differential data, the GNSS monitoring method is used to perform real-time automatic monitoring of the dam surface displacement.

5. The safety monitoring method for a concrete face rockfill dam according to claim 2, characterized in that: The automatic monitoring system of the water tube sedimentation meter consists of a measurement and control device, a water tube sedimentation meter control device, an observation cabinet and a connecting pipe. The automatic control device of the water tube sedimentation meter receives the control command of the measurement and control device in the safety monitoring system to automatically add water, stabilize the delay, automatically find the water surface, and measure the water level.

6. A safety monitoring method for a concrete face rockfill dam according to claim 2, characterized in that: The steel wire displacement meter comprises a tension wire horizontal displacement meter and a displacement sensor, and the displacement sensor is arranged on the steel wire of the measuring section at the loading end.

7. A safety monitoring method for a concrete face rockfill dam according to any one of claims 1 to 6, characterized in that: The proposed method for the early warning indicator includes:

1. Design specification method, which evaluates and analyzes the safety of dam operation by comparing the measured values ​​of dam safety monitoring with the following monitoring indicators; 1) Compare with multiple measurements under the same conditions in history; 2) Compare with the maximum and minimum values ​​in history; 3) Compare with the design, calculation and model test results; 4) Comparison with dam safety control indicators; 5) Compare with the forecast value; 2. Typical small probability method: for the measurement points with no obvious trend change and in compliance with the normal distribution test, the typical small probability method is used to formulate early warning indicators, and the monitoring value at the significance level of 1% is used as the proposed early warning indicator; 3. Confidence interval estimation method: select effective measuring points and use confidence interval estimation method to formulate early warning indicators. The monitoring value when the significance level is 1% is used as the proposed early warning indicator.

8. A safety monitoring method for a concrete face rockfill dam according to claim 7, characterized in that: The early warning modes of the safety monitoring system include 1. If the monitoring value of the measuring point does not exceed the assessment threshold, and no hidden dangers or lesions that affect safety are found during the inspection, the dam is considered to be in safe operation; 2. If the monitoring value of a measuring point exceeds the judgment threshold, a "measurement value abnormality reminder" message will be sent to the reservoir monitoring personnel, prompting them to conduct additional measurements; if the measurement value returns to within the judgment threshold after the additional measurement, the "measurement value abnormality reminder" message will be cancelled; if the additional measurement value still exceeds the judgment threshold, and the inspection finds hidden dangers and lesions that affect safety, a "dam safety reminder" message will be sent, and an expert consultation and review will be initiated to determine whether to issue a "dam safety warning" message; if the inspection does not find any hidden dangers and lesions that affect safety, an evaluation will be conducted in combination with the monitoring conditions of nearby related measuring points; 3. If the measuring point exceeding the assessment threshold is a "general" monitoring level measuring point, check the measurement value of the adjacent "key" monitoring level measuring point. If the measurement value of the "key" monitoring level measuring point exceeds the assessment threshold, issue a "dam safety reminder" message, initiate expert consultation and review, and determine whether to issue a "dam safety warning" message. If the measurement value of the "key" monitoring level measuring point does not exceed the warning value, issue a "measurement value abnormality, strengthen monitoring and inspection" message to the monitoring personnel; 4. If the measurement point that exceeds the judgment threshold is a "key" monitoring level measurement point, check the measurement value of the adjacent related monitoring measurement points. If the measurement value of the related measurement point exceeds the judgment threshold, issue a "dam safety reminder" message, initiate expert consultation and review, and determine whether to issue a "dam safety warning" message. If the measurement value of the related measurement point does not exceed the judgment threshold, check whether the measurement value of the measurement point that exceeds the judgment threshold has a trend change. If there is a trend change, issue a "dam safety reminder" message, initiate expert consultation and review, and determine whether to issue a "dam safety warning" message; If there is no trend change, send a message to the monitoring personnel that "abnormal measurement values, strengthen monitoring and inspection"; 5. For monitoring points where early warning indicators are formulated using multiple methods, when the measured value exceeds the early warning indicator of the confidence interval method, a safety warning shall be issued according to the above steps; when it exceeds the early warning indicator of the standard method or the small probability method, a "dam safety reminder" message shall be directly issued after eliminating the measurement error, and an expert consultation and review shall be initiated to determine whether to issue a "dam safety warning" message.

9. A water tube type settlement instrument used in the safety monitoring method of a concrete face rockfill dam according to claim 5, characterized in that: The measuring head comprises a water inlet pipe, an overflow port for determining the water level is arranged on the water inlet pipe, and an electric signal device for sending an electric signal to the system when the water inlet pipe reaches a predetermined water level is arranged on the water inlet pipe.

10. A water tube sedimentation instrument according to claim 9, characterized in that: The electric signal device comprises a fixed electrode and a movable electrode, wherein the movable electrode is arranged on a floating block in a water inlet pipe, and the water inlet pipe is arranged as follows: It comprises a first pipe section and a second pipe section, the first pipe and the second pipe section are fixedly connected, an overflow port is provided at the upper end of the first pipe section, a limit block is provided in the first pipe section or the second pipe section, and the floating block has a step surface matched with the limit block, and is used to lift the floating block when water with a certain pressure flows into the water inlet pipe, so that the movable electrode contacts the fixed electrode to send out an electrical signal; or The water inlet pipe includes a first pipe section, a second pipe section and a branch pipe. The first pipe section, the second pipe section and the branch pipe are closed to the internal space of the measuring head. The branch pipe is connected to the overflow port so that the water in the water inlet pipe flows into the branch pipe from the overflow port. The lower end of the branch pipe is connected to the lower end of the first pipe section through a one-way valve. A rigid air inlet pipe is fixed to the upper end of the second pipe section. The air inlet pipe passes through a float block. A limit block is set at the lower end of the air inlet pipe. In this way, when the water level of the water inlet pipe reaches the overflow port, the movable electrode on the float block contacts the fixed electrode.

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