A monitoring and early warning method for arch dam abutment resistance body and dam foundation stability

Abstract

The present invention discloses a monitoring and early warning method for the stability of an arch dam abutment resistance body and a dam foundation, including a complete set of monitoring methods for the stability of an arch dam abutment resistance body and a dam foundation, to realize the automatic observation of the deformation of the abutment resistance body and the dam foundation. According to the statistical regression model, the numerical simulation model, and the research results of the instability failure mode and instability criterion of the arch dam, a data-driven and physically-driven arch dam foundation overall stability monitoring and early warning model is constructed. The present invention establishes a safety monitoring model of the entire system of the arch dam, dam foundation and abutment resistance body of "real-time monitoring and analysis + dynamic feedback simulation", proposes graded control indicators for the deformation of the resistance body and the dam foundation, realizes the dynamic analysis, prediction, early warning of the overall safety and stability of the dam, and the rapid preview of adverse working conditions, and proposes suggestions for disposal measures.

Description

Technical Field

[0001] The invention relates to the technical field of hydropower engineering, and in particular to a monitoring and early warning method for the stability of an arch dam shoulder resistance body and a dam foundation. Background Art

[0002] An arch dam is a statically indeterminate structure that relies on the arch and beam to transfer the upstream hydraulic load to the dam shoulders and foundation on both sides. It has the characteristics of small volume, full concrete performance and large bearing capacity. Arch dams have high requirements for topographic and geological conditions. They are generally required to be built in V-shaped valleys with a relatively small width and height ratio. The design only considers the limited elastic deformation of the bedrock under the operation load. Since arch dams are more sensitive to foundation deformation, once the deformation is large, it will exceed the design allowable range, which may have a serious adverse impact on the safety of the dam body. The rare serious arch dam accidents in history are mainly caused by foundation deformation, such as the collapse of the Malpasset arch dam in France, the cracking of the dam body due to valley shrinkage in the Beauregard arch dam in Italy and the Zeuzier arch dam in Switzerland. The valley shrinkage deformation phenomenon occurred in the Xiluodu arch dam in China after water storage. Up to now, the cumulative shrinkage of the valley is about 74mm to 112mm, which exceeds the original foundation design deformation and forms a squeezing effect on the dam body. Therefore, the stability of the dam foundation, especially the resistance body, is crucial to the crack resistance and overall safety of the arch dam. In addition, there are potential sliding blocks on the abutments of some arch dams, which are composed of steep and gently inclined structural surfaces, developed joints and fissures, and downstream free surfaces. After water storage, the abutment resistance body may deform along the structural surface under the action of arch thrust and seepage load, thus affecting the overall stability and safety of the arch dam. The instability and failure of arch dams is generally a process from quantitative change to qualitative change. It is of great significance to conduct safety analysis and evaluation of the arch dam-foundation system in a timely manner, master the working state of the dam and its foundation and abutment rock mass, and discover potential safety risks, in order to ensure the long-term safety of the dam.

[0003] At present, there are three main methods for analyzing the anti-sliding stability of arch dams: rigid limit equilibrium method, numerical simulation and model test. Among them, the rigid limit equilibrium method is simplified in calculation and can quickly analyze the stability index for design application, namely the safety factor. It is the main method used in the arch dam design specification. However, the rigid limit equilibrium method assumes that the potential sliding block is a rigid body, ignores the deformation of the block itself and the deformation coupling between the dam body and the rock mass, and cannot reflect the interaction between the arch dam and the foundation and the overall safety state. The numerical simulation method can reflect the interaction between the arch dam and the dam foundation rock mass and more realistic boundary conditions and load conditions, but the physical and mechanical parameters of the dam foundation rock mass and the structural surface mostly use design values, which are quite different from the actual situation. The model test method can intuitively simulate the stress magnitude and distribution in the arch dam and the dam foundation, and can directly observe and record the deformation, failure mechanism and development process of the structure. Model tests help to derive some laws, but it is difficult for model tests to be completely similar to the prototype, and the physical and mechanical indicators of the rock mass are not easy to determine. Its results are limited and may not have universal significance. Therefore, the development of an arch dam abutment resistance body and dam foundation stability monitoring device and analysis and early warning method is of great significance to the arch dam water storage, operation safety, and promoting industry technological progress.

[0004] In view of the above problems, the present invention provides a method for realizing automatic observation of deformation of dam abutment resistance body and dam foundation and a method for monitoring and early warning of stability of arch dam abutment resistance body and dam foundation. Summary of the invention

[0005] The invention provides a method for realizing automatic observation of deformation of dam shoulder resistance body and dam foundation and a method for monitoring and early warning of stability of arch dam shoulder resistance body and dam foundation.

[0006] The purpose of the present invention is to provide a monitoring and early warning method for the stability of an arch dam shoulder resistance body and a dam foundation. The monitoring and early warning method includes monitoring installation, monitoring data, analyzing data and building an early warning model.

[0007] Further, the specific steps of monitoring installation are as follows:

[0008] Step 1: First, conduct on-site investigation and research, select the controlling structural surface that affects the arch dam's resistance body and the stability of the dam foundation, study and formulate a specific monitoring implementation plan and carry out on-site installation of monitoring instruments, install deep rock deformation monitoring instruments and seepage pressure meters, first drill inclined holes at different parts of the structural surface, the diameter of the inclined hole is about 110mm, and the depth of the inclined hole is based on the basic requirement of penetrating the controlling structural surface. According to the actual situation on site, the distance between the inclined holes is 5-10m, and magnetic grid flexible inclinometers and seepage pressure meters are installed at different elevations in the inclined holes, so as to realize the automatic observation of the deformation and seepage pressure of the controlling structural surface;

[0009] Step 2: When deploying surface displacement monitoring instruments based on magnetic grating technology on the surfaces of the resistance bodies on the left and right banks, first select the measurement points and fixed point positions. The distance between the measurement points and the fixed points is 5m, and a measurement path is formed between the points. Each measuring line is as tight as possible and always kept as a straight line. Different measuring lines and measuring points together form a monitoring network to realize the automated observation of the surface deformation of the resistance body.

[0010] Furthermore, the monitoring data includes deformation monitoring of the control structure surface of the resisting body, deformation monitoring of the control structure surface of the dam foundation and deformation monitoring of the surface of the resisting body. The specific steps of deformation monitoring of the control structure surface of the resisting body are as follows:

[0011] Step 1: Select the controlling structural surface that affects the stability of the arch dam abutment resistance body, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer;

[0012] Step 2: Place piezometers at different depths of the inclinometer tube to monitor the displacement deformation, opening and seepage pressure of the resistance body structural surface at different elevations.

[0013] Furthermore, the specific steps for monitoring the deformation of the dam foundation control structure surface are as follows:

[0014] Step 1: Select the controlling structural surface that affects the stability of the arch dam foundation, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer;

[0015] Step 2: Install piezometers at different depths of the inclinometer tube to monitor the displacement, deformation, opening and seepage pressure of the dam foundation structure at different elevations.

[0016] Furthermore, the specific steps of monitoring the surface deformation of the resistance body are as follows:

[0017] Step 1: Place magnetic grating displacement meters on the surface of the dam abutment resistance body to monitor the spatial distribution characteristics of the deformation of the resistance body surface and its changes over time.

[0018] Further, the specific steps for analyzing the data are as follows:

[0019] Step 1: Combine deep deformation monitoring with surface deformation monitoring, develop monitoring data collection, transmission and analysis software, form a complete set of arch dam abutment resistance body and dam foundation stability monitoring methods, devices and software, and ensure that they are suitable for various environmental conditions at the project site and meet the engineering monitoring accuracy requirements. Comprehensively analyze the deformation and seepage pressure monitoring data of the left and right bank abutment resistance bodies, study the spatial distribution characteristics of resistance body deformation and seepage pressure and their evolution laws over time, establish a statistical regression model for the deformation of the abutment resistance body and dam foundation, separate deformation components such as water pressure, seepage, temperature, time, rainfall, etc., combine engineering geology, ground stress distribution characteristics and changes in hydrogeological conditions during engineering construction and water storage, study and propose the dominant factors of deformation, propose a deformation and seepage pressure prediction method based on statistical regression and deep learning, predict the deformation and seepage pressure evolution trend of the resistance body and dam foundation, and combine the dam monitoring data to establish a data-driven monitoring model for the arch dam abutment resistance body and dam foundation.

[0020] Furthermore, the specific steps of building an early warning model are as follows:

[0021] Step 1: Based on the design data and geological survey data, a high-resolution numerical simulation model of the arch dam-foundation is constructed to truly reflect the shape of the arch dam body, the shape of the river valley, the rock mass division and the main structural surface. Based on the monitoring data, the three-dimensional finite element water-heat-force multi-field coupling analysis method and the artificial intelligence method are used to invert the surface deformation of the dam shoulder resistance body, the deformation of the dam shoulder resistance body and the dam foundation structural surface, and the seepage pressure. The calculated values ​​are compared with the monitored values, and the physical and mechanical parameters such as the permeability coefficient, deformation modulus, and strength of the rock mass are dynamically calibrated. The whole-dam full-process finite element simulation method is used to conduct a full-process dynamic simulation analysis of the temperature, seepage, deformation, and stress working state of the arch dam body, dam foundation, dam shoulder rock mass, and main structural surface during the construction and water storage stages. The overall safety and stability of the arch dam are evaluated based on the analysis results.

[0022] Step 2: Use nonlinear finite element overload or reduced strength analysis method to analyze the damage evolution process, anti-sliding stability weak points and instability failure modes of the arch dam, dam foundation and dam shoulder resistance body, propose instability criteria, and calculate the overall stability safety of the arch dam. Based on statistical regression models, numerical simulation models, and research results on arch dam instability failure modes and instability criteria, a data-driven and physically-driven arch dam-foundation overall monitoring model is constructed, and safety classification standards and deformation control indicators for arch dams, dam shoulder resistance bodies and dam foundations are proposed. Dynamic analysis and prediction of the seepage pressure, deformation, stress structural properties and anti-sliding stability of the arch dam, dam foundation and resistance body are carried out, intelligent early warning of safety risks is carried out, and rapid rehearsal of adverse working conditions is carried out. Suggested countermeasures are proposed based on early warning information and rehearsal results.

[0023] The present invention has the following advantages: The present invention forms a complete set of monitoring methods for the stability of the arch dam abutment resistance body and the dam foundation, and realizes the automatic observation of the deformation of the dam abutment resistance body and the dam foundation. According to the statistical regression model, the numerical simulation model and the research results of the instability failure mode and instability criterion of the arch dam, a data-driven and physically-driven arch dam-foundation overall stability monitoring and early warning model is constructed to realize the dynamic analysis, prediction, early warning of the overall safety and stability of the dam and the rapid preview of adverse working conditions, and put forward suggestions for disposal measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a deformation monitoring diagram of the controllable structural surface of the resistance body of the present invention;

[0025] Figure 2 It is a deformation monitoring diagram of the dam foundation control structure surface of the present invention;

[0026] Figure 3 It is a deformation monitoring diagram of the surface of the force-resisting body of the present invention;

[0027] Figure 4 It is a diagram showing the structure of the monitoring data acquisition and transmission system of the present invention;

[0028] Figure 5 The dam body shape, river valley shape, rock mass division and main structural surface diagram of the arch dam of the present invention;

[0029] Figure 6 It is the technical roadmap of the present invention. DETAILED DESCRIPTION

[0030] The present invention provides a monitoring and early warning method for the stability of an arch dam shoulder resistance body and a dam foundation. The monitoring and early warning method comprises monitoring installation, monitoring data, analyzing data and constructing an early warning model.

[0031] In this embodiment, the specific steps of monitoring installation are as follows:

[0032] Step 1: First, conduct on-site investigation and research, select the controlling structural surface that affects the arch dam's resistance body and the stability of the dam foundation, study and formulate a specific monitoring implementation plan and carry out on-site installation of monitoring instruments, install deep rock deformation monitoring instruments and seepage pressure meters, first drill inclined holes at different parts of the structural surface, the diameter of the inclined hole is about 110mm, and the depth of the inclined hole is based on the basic requirement of penetrating the controlling structural surface. According to the actual situation on site, the distance between the inclined holes is 5-10m, and magnetic grid flexible inclinometers and seepage pressure meters are installed at different elevations in the inclined holes, so as to realize the automatic observation of the deformation and seepage pressure of the controlling structural surface;

[0033] Step 2: When deploying surface displacement monitoring instruments based on magnetic grating technology on the surfaces of the resistance bodies on the left and right banks, first select the measurement points and fixed point positions. The distance between the measurement points and the fixed points is 5m, and a measurement path is formed between the points. Each measuring line is as tight as possible and always kept as a straight line. Different measuring lines and measuring points together form a monitoring network to realize the automated observation of the surface deformation of the resistance body.

[0034] In this embodiment, the monitoring data includes deformation monitoring of the control structure surface of the resisting body, deformation monitoring of the control structure surface of the dam foundation and deformation monitoring of the surface of the resisting body. The specific steps of deformation monitoring of the control structure surface of the resisting body are as follows:

[0035] Step 1: Select the controlling structural surface that affects the stability of the arch dam abutment resistance body, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer;

[0036] Step 2: Place piezometers at different depths of the inclinometer tube to monitor the displacement deformation, opening and seepage pressure of the resistance body structural surface at different elevations.

[0037] In this embodiment, the specific steps of monitoring the deformation of the dam foundation control structure surface are as follows:

[0038] Step 1: Select the controlling structural surface that affects the stability of the arch dam foundation, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer;

[0039] Step 2: Install piezometers at different depths of the inclinometer tube to monitor the displacement, deformation, opening and seepage pressure of the dam foundation structure at different elevations.

[0040] In this embodiment, the specific steps of monitoring the deformation of the resistance body surface are as follows:

[0041] Step 1: Place magnetic grating displacement meters on the surface of the dam abutment resistance body to monitor the spatial distribution characteristics of the deformation of the resistance body surface and its changes over time.

[0042] In this embodiment, the specific steps of analyzing data are as follows:

[0043] Step 1: Combine deep deformation monitoring with surface deformation monitoring, develop monitoring data collection, transmission and analysis software, form a complete set of arch dam abutment resistance body and dam foundation stability monitoring methods, devices and software, and ensure that they are suitable for various environmental conditions at the project site and meet the engineering monitoring accuracy requirements. Comprehensively analyze the deformation and seepage pressure monitoring data of the left and right bank abutment resistance bodies, study the spatial distribution characteristics of resistance body deformation and seepage pressure and their evolution laws over time, establish a statistical regression model for the deformation of the abutment resistance body and dam foundation, separate deformation components such as water pressure, seepage, temperature, time, rainfall, etc., combine engineering geology, ground stress distribution characteristics and changes in hydrogeological conditions during engineering construction and water storage, study and propose the dominant factors of deformation, propose a deformation and seepage pressure prediction method based on statistical regression and deep learning, predict the deformation and seepage pressure evolution trend of the resistance body and dam foundation, and combine the dam monitoring data to establish a data-driven monitoring model for the arch dam abutment resistance body and dam foundation.

[0044] In this embodiment, the specific steps of building the early warning model are as follows:

[0045] Step 1: Based on the design data and geological survey data, a high-resolution numerical simulation model of the arch dam-foundation is constructed to truly reflect the shape of the arch dam body, the shape of the river valley, the rock mass division and the main structural surface. Based on the monitoring data, the three-dimensional finite element water-heat-force multi-field coupling analysis method and the artificial intelligence method are used to invert the surface deformation of the dam shoulder resistance body, the deformation of the dam shoulder resistance body and the dam foundation structural surface, and the seepage pressure. The calculated values ​​are compared with the monitored values, and the physical and mechanical parameters such as the permeability coefficient, deformation modulus, and strength of the rock mass are dynamically calibrated. The whole-dam full-process finite element simulation method is used to conduct a full-process dynamic simulation analysis of the temperature, seepage, deformation, and stress working state of the arch dam body, dam foundation, dam shoulder rock mass, and main structural surface during the construction and water storage stages. The overall safety and stability of the arch dam are evaluated based on the analysis results.

[0046] Step 2: Use nonlinear finite element overload or reduced strength analysis method to analyze the damage evolution process, anti-sliding stability weak points and instability failure modes of the arch dam, dam foundation and dam shoulder resistance body, propose instability criteria, and calculate the overall stability safety of the arch dam. Based on statistical regression models, numerical simulation models, and research results on arch dam instability failure modes and instability criteria, a data-driven and physically-driven arch dam-foundation overall monitoring model is constructed, and safety classification standards and deformation control indicators for arch dams, dam shoulder resistance bodies and dam foundations are proposed. Dynamic analysis and prediction of the seepage pressure, deformation, stress structural properties and anti-sliding stability of the arch dam, dam foundation and resistance body are carried out, intelligent early warning of safety risks is carried out, and rapid rehearsal of adverse working conditions is carried out. Suggested countermeasures are proposed based on early warning information and rehearsal results.

[0047] Although the specific embodiments of the present invention are described in detail in conjunction with the accompanying drawings, it should not be understood as limiting the scope of protection of the present invention. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still belong to the scope of protection of the present invention.

Claims

1. A monitoring and early warning method for the stability of an arch dam abutment resistance body and a dam foundation, characterized in that: The monitoring and early warning method includes monitoring installation, monitoring data, analyzing data and building an early warning model; The specific steps of the monitoring installation are as follows: Step 1: First, conduct on-site investigation and research, select the controlling structural surface that affects the arch dam's resistance body and the stability of the dam foundation, study and formulate a specific monitoring implementation plan and carry out on-site installation of monitoring instruments, install deep rock deformation monitoring instruments and seepage pressure meters, first drill inclined holes at different parts of the structural surface, the depth of the inclined holes is based on the basic requirement of penetrating the controlling structural surface, according to the actual situation on site, the distance between the inclined holes is 5-10m, and magnetic grid flexible inclinometers and seepage pressure meters are installed at different elevations in the inclined holes, so as to realize the automatic observation of the deformation and seepage pressure of the controlling structural surface; Step 2: When laying out the surface displacement monitoring instrument based on magnetic grating technology on the surface of the resistance body on the left and right banks, first select the measurement point and the fixed point position. The distance between the measurement point and the fixed point is 5m, and a measurement path is formed between points. Each measurement line is as tight as possible and always kept as a straight line. Different measurement lines and measurement points together form a monitoring network to realize the automatic observation of the surface deformation of the resistance body; The monitoring data includes deformation monitoring of the control structure surface of the resisting body, deformation monitoring of the control structure surface of the dam foundation and deformation monitoring of the surface of the resisting body. The specific steps of deformation monitoring of the control structure surface of the resisting body are as follows: Step 1: Select the controlling structural surface that affects the stability of the arch dam abutment resistance body, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer; Step 2: Install piezometers at different depths of the inclinometer tube to monitor the displacement deformation, opening and seepage pressure of the resistance body structure surface at different elevations; The specific steps of analyzing the data are as follows: Step 1: Combine deep deformation monitoring with surface deformation monitoring, develop monitoring data acquisition, transmission and analysis software, form a complete set of arch dam abutment resistance body and dam foundation stability monitoring methods, devices and software, and ensure that they are suitable for various environmental conditions at the project site and meet the engineering monitoring accuracy requirements, comprehensively analyze the deformation and seepage pressure monitoring data of the left and right bank abutment resistance bodies, study the spatial distribution characteristics of resistance body deformation and seepage pressure and the evolution law over time, establish a statistical regression model for the deformation of the abutment resistance body and dam foundation, separate the water pressure, seepage, temperature, time effect, and rainfall deformation components, combine the engineering geology, ground stress distribution characteristics and the changes in hydrogeological conditions during engineering construction and water storage, study and propose the dominant factors of deformation, propose a deformation and seepage pressure prediction method based on statistical regression and deep learning, predict the deformation and seepage pressure evolution trend of the resistance body and dam foundation, and establish a data-driven monitoring model for the abutment resistance body and dam foundation based on dam monitoring data; The specific steps of constructing the early warning model are as follows: Step 1: Based on the design data and geological survey data, a high-resolution numerical simulation model of the arch dam-foundation is constructed to truly reflect the shape of the arch dam body, the shape of the river valley, the rock mass division and the main structural surface. Based on the monitoring data, the three-dimensional finite element water-heat-force multi-field coupling analysis method and the artificial intelligence method are used to invert the surface deformation of the dam shoulder resistance body, the deformation of the dam shoulder resistance body and the dam foundation structural surface, and the seepage pressure. The calculated values ​​are compared with the monitored values, and the permeability coefficient, deformation modulus, and strength physical and mechanical parameters of the rock mass are dynamically calibrated. The whole-dam full-process finite element simulation method is used to conduct a full-process dynamic simulation analysis of the temperature, seepage, deformation, and stress working state of the arch dam body, dam foundation, dam shoulder rock mass, and main structural surfaces during the construction and water storage stages. The overall safety and stability of the arch dam are evaluated based on the analysis results. Step 2: Use nonlinear finite element overload or reduced strength analysis method to analyze the damage evolution process, anti-sliding stability weak points and instability failure modes of the arch dam, dam foundation and dam shoulder resistance body, propose instability criteria, and calculate the overall stability safety of the arch dam. Based on statistical regression models, numerical simulation models, and research results on arch dam instability failure modes and instability criteria, a data-driven and physically-driven arch dam-foundation overall monitoring model is constructed, and safety classification standards and deformation control indicators for arch dams, dam shoulder resistance bodies and dam foundations are proposed. Dynamic analysis and prediction of the seepage pressure, deformation, stress structural properties and anti-sliding stability of the arch dam, dam foundation and resistance body are carried out, intelligent early warning of safety risks is carried out, and rapid rehearsal of adverse working conditions is carried out. Suggested countermeasures are proposed based on early warning information and rehearsal results.

2. The method for monitoring and early warning of the stability of an arch dam abutment and a dam foundation according to claim 1, characterized in that: The specific steps of the dam foundation control structure surface deformation monitoring are as follows: Step 1: Select the controlling structural surface that affects the stability of the arch dam foundation, drill holes at key locations of the structural surface, and bury a magnetic grid flexible inclinometer; Step 2: Install piezometers at different depths of the inclinometer tube to monitor the displacement, deformation, opening and seepage pressure of the dam foundation structure at different elevations.

3. The method for monitoring and early warning of the stability of an arch dam abutment and a dam foundation according to claim 1, characterized in that: The specific steps of monitoring the surface deformation of the resistance body are as follows: Step 1: Place magnetic grating displacement meters on the surface of the dam abutment resistance body to monitor the spatial distribution characteristics of the deformation of the resistance body surface and its changes over time.

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