Numerical simulation and stability analysis method and system based on monitoring data

Abstract

The invention provides a numerical simulation and stability analysis method and system based on monitoring data, and belongs to the technical field of monitoring and early warning. The problems that in the slope monitoring technology, data collecting and processing efficiency is low, calculation model precision and adaptability are poor, dynamic monitoring of slope stability lacks pertinence, the system integration degree is low, cost is high, and application is complex are solved. The method comprises the steps that slope data are collected in real time through a multifunctional sensor; transmitting the acquired data to a data acquisition system for real-time data monitoring and recording; a two-dimensional numerical model of the side slope is constructed through finite element analysis software, and the side slope is analyzed through the two-dimensional numerical model; and comparing and analyzing real-time monitoring data in the data acquisition system and a numerical simulation calculation result, analyzing the change trend of the side slope, identifying a potential instability area, updating the two-dimensional numerical model in real time by using an automatic algorithm, completing real-time dynamic evaluation of the side slope, and early warning potential side slope instability risks in advance.

Description

Technical Field

[0001] The invention relates to a numerical simulation and stability analysis method and system based on monitoring data, belonging to the technical field of monitoring and early warning. Background Art

[0002] In recent years, with the rapid development of the national economy and the increase in infrastructure construction, slope support projects have been widely used in engineering construction, especially in some high slope projects with large heights and slopes. High slope support projects are widely used in engineering fields such as roads, railways, water conservancy, and construction, and have played an important role in ensuring slope stability and avoiding disasters. Traditional slope stability assessments rely on manual inspections and conventional monitoring methods, such as inclinometers, pore water pressure gauges and other equipment for data collection, and manual analysis to determine slope stability. However, these methods often have the following problems: 1. Monitoring data is difficult to update in real time: Traditional monitoring methods often rely on manual reading or periodic inspections, resulting in poor real-time data and difficulty in timely detection of potential slope instability risks. 2. Model calculations are not accurate enough: Most of the existing slope stability assessment methods use empirical formulas or traditional finite element analysis methods, but due to the limitations of calculation accuracy and complexity, it is difficult to accurately simulate the force and displacement of slopes under complex geological conditions. 3. Unable to fully reflect the dynamic changes of the slope: The existing monitoring methods and calculation models can usually only provide static or periodic data, and cannot fully reflect the dynamic stability evolution of the slope under different climate and soil changes. 4. The manual analysis workload is large and the efficiency is low: Traditional stability analysis often relies on a large amount of manual analysis, which is difficult to process large-scale data, has low analysis efficiency, and the results are often affected by the experience and judgment of the analysts, which is prone to errors.

[0003] The existing slope monitoring technology has the following shortcomings: 1. Low efficiency of data collection and processing: Existing slope monitoring methods usually collect data through manual inspection or intermittently, which lacks real-time performance. The data obtained through manual inspection cannot meet the needs of accurate monitoring of dynamic changes in slope stability, and the manual collection and analysis process is cumbersome and inefficient.

[0004] 2. Poor accuracy and adaptability of the calculation model: Although the finite element analysis method has been widely used in slope stability analysis, the finite element model in the existing technology often lacks sufficient accuracy and adaptability when facing complex geological conditions, especially in terms of stress, displacement, plastic strain, etc. of high slopes. The accuracy and reliability of the existing model are insufficient, resulting in deviations between the calculation results and the actual situation. 3. The dynamic monitoring of slope stability lacks pertinence: The existing monitoring technology usually uses a single static data, which makes it difficult to dynamically monitor the changes of the slope under different construction stages and different environmental conditions, and cannot effectively warn of the risk of slope instability, making it difficult to take effective protective measures in time. 4. Low system integration: The existing slope monitoring and numerical simulation technologies are usually scattered, lacking effective integration and coordination, resulting in the inability to efficiently connect the monitoring data with the simulation data, and unable to form a complete evaluation system, resulting in insufficient credibility and accuracy of the analysis results. 5. High cost and complex application: Some current high-precision numerical simulation software and monitoring equipment have high costs, complex operations, and high technical requirements for users, which limits their widespread application in some small and medium-sized projects. Summary of the invention

[0005] The present invention aims to solve the problems of low data acquisition and processing efficiency, poor calculation model accuracy and adaptability, lack of pertinence in dynamic monitoring of slope stability, low system integration, high cost and complex application in slope monitoring technology, and thus proposes a numerical simulation and stability analysis method and system based on monitoring data, wherein the analysis method specifically includes:

[0006] Step 1: Use multifunctional sensors to collect slope data in real time;

[0007] Step 2: Transmit the collected data of the sensor to the data acquisition system for real-time data monitoring and recording;

[0008] Step 3: Use finite element analysis software to construct a two-dimensional numerical model of the slope, analyze the slope through the two-dimensional numerical model, and obtain the numerical simulation calculation results of the slope;

[0009] Step 4: Compare and analyze the real-time monitoring data in the data acquisition system and the numerical simulation calculation results, analyze the changing trend of the slope, identify potential unstable areas, and use automated algorithms to update the two-dimensional numerical model in real time to complete real-time dynamic evaluation of the slope and provide early warning of potential slope instability risks.

[0010] Preferably, the multifunctional sensor in step 1 includes but is not limited to a displacement sensor, a stress sensor and a pore water pressure gauge, and the collected slope data includes but is not limited to the displacement, stress, plastic strain and pore water pressure of the slope.

[0011] Preferably, the data monitoring results in step 2 include but are not limited to displacement changes on the slope surface and inside, stress changes, plastic strain areas and stress-strain relationships of the soil, and environmental data related to geology and climate change.

[0012] Preferably, analyzing the slope by using a two-dimensional numerical model in step 3 specifically includes:

[0013] Input slope soil parameters into the two-dimensional numerical model for static and dynamic analysis;

[0014] Through static analysis and calculation, the force distribution, displacement cloud diagram and plastic strain area of ​​the slope soil under different working conditions are obtained;

[0015] Through dynamic analysis, the Moore-Coulomb criterion is used to simulate the instability and landslide behavior of the slope under the action of external forces and environmental changes, and the slope is dynamically analyzed to evaluate the stability of the slope.

[0016] Preferably, the step of kinetic analysis comprises:

[0017] Step 3.1: Divide the slope rock mass into finite element units;

[0018] Step 3.2: Determine the node displacement mode so that the displacement function at the node is equal to the node displacement and meets the convergence criterion;

[0019] Step 3.3: Calculate the stiffness matrix between the node displacement and element strain in the slope element;

[0020] Step 3.4: Obtain the overall characteristic equation of the slope based on the stiffness matrix between the node displacement and the element strain;

[0021] Step 3.5: Constrain the boundaries of the finite element units of the slope, extract the unit parts that are excluded from the influence, and solve the overall characteristic equation of the slope to complete the dynamic analysis and obtain the node displacement and unit stress.

[0022] Preferably, step 3.3 specifically includes:

[0023] Step 3.3.1: Obtain the shear strength of any point in the finite element unit through the cohesion, shear stress and internal friction angle of the slope rock and soil;

[0024] Step 3.3.2: The safety factor of any point in the finite element unit is calculated by using the shear strength and shear stress and the Mohr-Coulomb yield criterion;

[0025] Step 3.3.3: Perform strength reduction process based on the shear strength and safety factor of the corresponding points to obtain the stiffness matrix between the node displacement and unit strain in the slope unit.

[0026] Preferably, step 4 specifically includes:

[0027] Compare and analyze the real-time monitoring data in the data acquisition system and the numerical simulation calculation results to verify the accuracy of the two-dimensional numerical model. If the accuracy is lower than the preset value, adjust the parameters of the two-dimensional numerical model until the accuracy is not lower than the preset value;

[0028] By comparing the real-time monitoring data with the numerical simulation calculation results, the stability of the slope is judged, the change trend of the slope is analyzed, and the potential unstable area is identified. The change trend of the slope includes but is not limited to the displacement, stress, and plastic strain of the slope;

[0029] An automated algorithm is used to update the two-dimensional numerical model in real time, enabling real-time dynamic assessment of the slope and early warning of potential slope instability risks.

[0030] Numerical simulation and stability analysis methods based on monitoring data, including:

[0031] Sensor module, used to collect slope data in real time;

[0032] The data acquisition system module is used to monitor and record real-time data and transmit the monitoring data to the data processing and analysis module;

[0033] A power supply module is used to provide a stable power supply for the data acquisition system module;

[0034] Two-dimensional numerical model module, used for numerical simulation of slopes;

[0035] Data processing and analysis module, used to compare and analyze numerical simulation results and real-time data, evaluate the stability of the slope and issue warning information when the warning threshold is exceeded;

[0036] The user interaction module is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time, and adjust system parameters according to user settings.

[0037] Preferably, the data processing and analysis module includes a data receiving submodule, a comparison and analysis submodule, and an early warning and reporting submodule;

[0038] The data receiving submodule is used to receive monitoring data from the data acquisition system module;

[0039] The comparative analysis module is used to compare and analyze the numerical simulation results with real-time data, evaluate the stability of the slope, and output a real-time evaluation report;

[0040] The warning and reporting submodule is used to generate stability reports based on the evaluation results and issue warning information when the warning threshold is exceeded.

[0041] Preferably, the user interaction module includes a display screen and a control submodule;

[0042] The display screen is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time;

[0043] The control submodule allows the user to perform operation settings, where the operation settings include but are not limited to adjusting the monitoring frequency, setting the warning threshold, and querying historical data.

[0044] The beneficial effects of the present invention are:

[0045] 1. Strong real-time performance and improved early warning capabilities: Existing slope monitoring technologies usually rely on manual inspections and periodic data collection, which results in delayed data updates and makes it difficult to reflect slope changes in a timely manner. However, the present invention monitors the displacement, stress, plastic strain and other changes of the slope in real time, and can capture and update data in a timely manner when the slope shows signs of instability. This real-time performance greatly improves the ability to monitor the dynamic changes of the slope and provides more timely early warning information for engineering managers. Through real-time comparison with numerical simulations, the present invention can detect potential instability risks in advance and avoid potential accidents caused by slow response in traditional methods.

[0046] 2. Improve the accuracy and adaptability of numerical models: In traditional slope stability assessments, finite element analysis methods often cannot accurately reflect the actual stress and deformation conditions of slopes under complex geological conditions, resulting in deviations between simulation results and actual conditions. The present invention combines Midas GTS NX finite element software and the Moore-Coulomb criterion, and introduces more sophisticated material parameters and nonlinear behavior of slopes into the soil constitutive model, making the model more accurate and adaptable. Through more accurate numerical simulations, the present invention can better reflect the force distribution, displacement changes, and stability evolution of the slope, ensuring the accuracy of the assessment results.

[0047] 3. Comprehensive dynamic analysis and stability assessment: The existing technology usually adopts static analysis, which cannot effectively consider the impact of environmental factors such as climate and geology on slope stability, and it is also difficult to dynamically analyze the stability of slopes at different construction stages. However, the present invention can comprehensively analyze the changes of slopes under different conditions, especially the dynamic stability changes of slopes under complex environmental conditions (such as rainfall, earthquakes, etc.) by integrating real-time monitoring data and dynamic numerical simulation. This dynamic assessment capability enables the present invention to more accurately identify potential instability risks and provide more reliable decision support for slope support projects.

[0048] 4. Improve the accuracy and reliability of slope stability assessment: The present invention can dynamically adjust the simulation model and calibrate the model parameters through real-time comparison of numerical simulation and monitoring data to ensure high accuracy and high reliability of the simulation results. Traditional methods often rely on empirical formulas and static models, lacking sufficient accuracy and flexibility. The present invention combines modern computing technology and real-time data to make slope stability assessment more scientific, objective and reliable. This not only improves the accuracy of slope stability analysis, but also provides a reliable prediction basis for various complex situations encountered in actual engineering.

[0049] 5. Enhanced environmental adaptability and reliability: The slope stability monitoring and analysis method of the present invention has strong environmental adaptability. By considering factors such as the geological characteristics of the area where the slope is located, climate change, and construction stage, the present invention can perform comprehensive stability analysis in multiple scenarios. Compared with traditional technologies, the system of the present invention is more capable of coping with complex and changeable environmental conditions and improving the reliability of slope stability assessment.

[0050] Summarize: BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A flow chart of a numerical simulation and stability analysis method based on monitoring data provided by the present invention;

[0052] Figure 2 The data monitoring layout diagram provided by the present invention;

[0053] Figure 3 Simplified CAD drawings of three natural working condition sections of the slope provided by the present invention;

[0054] Figure 4 A schematic diagram of the soil layer profile and grid division of the slope before leveling and support provided by the present invention;

[0055] Figure 5 Schematic diagram of plastic strain conditions of three slope sections provided by the present invention;

[0056] Figure 6 A schematic diagram of the overall displacement of three sections of the slope provided by the present invention;

[0057] Figure 7 A schematic diagram of shear force distribution of three sections of the slope provided by the present invention;

[0058] Figure 8 Simplified CAD drawings of three sections of the slope support working conditions provided by the present invention;

[0059] Fig. 9 The original grid division diagram of the slope support working conditions of the three sections provided by the present invention;

[0060] Fig.10 A schematic diagram of the plane plastic strain of three slope sections after support provided by the present invention;

[0061] Fig.11 A schematic diagram of the overall displacement of three sections of the slope after support provided by the present invention;

[0062] Fig.12 A schematic diagram of shear stress distribution after three sections of the slope are supported provided by the present invention;

[0063] Fig.13 A schematic diagram of the displacement in the X direction after three sections of the slope are supported provided by the present invention;

[0064] Fig.14 A schematic diagram of the Y-direction displacement of three slope sections after support provided by the present invention;

[0065] Fig.15 A framework diagram of the numerical simulation and stability analysis method based on monitoring data provided by the present invention. DETAILED DESCRIPTION

[0066] Specific implementation method 1: Combination Figure 1-14 To illustrate this embodiment, Figure 1 As shown, the steps of the numerical simulation and stability analysis method based on monitoring data described in this embodiment include:

[0067] S1: Use multifunctional sensors to collect slope data in real time;

[0068] In this implementation, the slope collection site is located in the slope support project on the south side of the cooling tower of the second phase of the Changsha sewage treatment plant sludge and domestic waste clean incineration coordinated disposal project. The project is located in the northernmost area of ​​the Heimifeng Waste Treatment Plant in Qiaoyi Town, Wangcheng District, Changsha City. The north and west sides are supported slopes, the south side is the studied slope and comprehensive water pump house, and the east side is the booster station and solid waste treatment site; the cooling tower ground elevation is 156.00m. There is a slope with a height difference of 16m on the south side of the cooling tower. Displacement sensors, stress sensors, and pore water pressure gauges are installed to monitor the displacement, stress, plastic strain, pore water pressure and other parameters of the slope in real time.

[0069] S2: Transmit the collected data of the sensor to the data acquisition system for real-time data monitoring and recording;

[0070] The data monitoring arrangement of this embodiment is as follows Figure 2 As shown, the monitoring content includes:

[0071] (1) Surface subsidence monitoring: The measurement content includes subsidence and change rate;

[0072] (2) Support pile tilt monitoring: A box-type inclinometer is placed on the support pile to monitor the tilt of the support pile during slope excavation, cooling tower construction and operation;

[0073] (3) Cooling tower tilt monitoring: During the construction of the cooling tower, a box-type inclinometer is placed on the cooling tower to monitor the changing state of the cooling tower under wind load during construction and operation;

[0074] (4) Groundwater level monitoring: monitoring the changing status of groundwater level during slope excavation, cooling tower construction and operation;

[0075] (5) Anchor stress monitoring: During anchor construction, a steel bar meter is welded to the anchor to monitor the changing state of anchor stress during slope excavation and operation;

[0076] (6) Flexible support main cable stress monitoring: During the construction of the flexible support net, the steel bar gauge is welded to the main cable to monitor whether there is rock falling during slope excavation and operation;

[0077] (7) Pile-anchor support stress monitoring: monitoring the stress state of the anchor cable;

[0078] (8) Pile reinforcement stress monitoring: The stress of reinforcement in the support pile is obtained through the reinforcement meter;

[0079] (9) Monitoring of soil pressure behind support piles: During the excavation of support piles, soil pressure gauges are buried to monitor the changing state of soil pressure behind support piles during slope excavation, cooling tower construction and operation;

[0080] (10) Platform soil pressure monitoring: After the cooling tower pile foundation construction is completed, a three-dimensional soil pressure gauge is buried with the help of a geological drill to monitor the changing state of soil pressure in the platform during slope excavation, cooling tower construction and operation;

[0081] The monitoring equipment used in this embodiment is shown in Table 1:

[0082] Table 1

[0083]

[0084]

[0085] S3: Use finite element analysis software to build a two-dimensional numerical model of the slope, analyze the slope through the two-dimensional numerical model, and obtain the numerical simulation calculation results of the slope;

[0086] Input slope soil parameters into the two-dimensional numerical model for static and dynamic analysis;

[0087] Through static analysis and calculation, the force distribution, displacement cloud diagram and plastic strain area of ​​the slope soil under different working conditions are obtained;

[0088] Through dynamic analysis, the Moore-Coulomb criterion is used to simulate the instability and landslide behavior of the slope under the action of external forces and environmental changes, and the slope is dynamically analyzed to evaluate the stability of the slope.

[0089] The finite element analysis software used in this implementation is Midas GTS NX. Midas GTS NX is a geotechnical analysis software that can be used to build models for geotechnical analysis. The software provides multiple functions such as slope analysis, static analysis, solid structure analysis, dynamic analysis, and thermal analysis, allowing users to analyze various geotechnical structures in a three-dimensional interface, which is very helpful for construction. The static slope analysis module of the software includes the finite element strength reduction method (SRM) and the stress analysis method (SAM) based on the limit equilibrium method. Midas GTS NX has powerful geometric modeling, meshing, and graphics processing functions, and calculates its deformation and internal force under different working conditions.

[0090] The finite element method needs to divide the entire slope rock and soil into a lot of different units with their own characteristics, and connect the different units into a whole by nodes, and there are forces acting on the nodes. In the use of the finite element method for numerical simulation modeling, the overall step is to divide it into different units and nodes, that is, to divide the grid, and then determine the characteristics of the forces of the units and nodes, and conduct an overall analysis after connecting them to obtain the equilibrium equation of the entire rock and soil body. After calculation, the results are obtained, and finally a specific analysis is performed based on the results of the model. The specific steps are as follows:

[0091] S301: Divide the entire slope rock and soil into finite element units to achieve discretization;

[0092] S302: Determine a displacement pattern so that the displacement function on the node is equal to the node displacement and the convergence criterion is satisfied;

[0093] S303: Based on the mechanical properties of the slope unit, the stiffness matrix between the node displacement and the unit strain is listed;

[0094] The definition of shear strength reduction coefficient is: when the external load on the rock and soil is a constant and acts on the rock and soil, the ratio of the shear stress generated by the external load on the rock and soil to the shear strength generated inside the slope to maintain its own stability is called the shear strength reduction coefficient. Under normal circumstances, we regard the ultimate state of the slope as the shear stress caused by the external load on the slope rock and soil and the internal balance of the slope rock and soil, and the slope is in a state between undamaged and damaged. In this case, if the load or the soil layer characteristics of the rock and soil body change a little, such as the increase of external load or the change of properties of the soil layer of the rock and soil body due to weathering or other factors, its overall shear strength decreases, and the slope will not continue to maintain a state of equilibrium, and then it will be damaged. The strength reduction method is used to analyze the safety and stability of the rock and soil body as follows:

[0095] S30301: Determine the shear strength at any point through the cohesion, stress and internal friction angle of the rock mass;

[0096] S30302: Calculate the safety factor of any point by the shear strength and shear stress of each point in the rock and soil mass;

[0097] S30303: Carry out strength reduction process.

[0098] This implementation method uses the simultaneous yield criterion in the strength reduction method analysis process, which is as follows:

[0099] Mohr-Coulomb yield criterion: If the slope slides along a certain sliding surface, all nodes and elements on the sliding surface are in a limit equilibrium state, and the expression is:

[0100]

[0101] In formula (1), τ f is the shear strength, σ′ is the normal effective stress, σ is the normal total stress, u is the pore water pressure, c′ is the effective cohesion, is the effective internal friction angle;

[0102] The safety factor is achieved by reducing the strength of the material to reach the limit equilibrium state. It has the nature of a strength reserve factor. The safety factor is the ratio of the shear strength on the entire sliding surface to the shear stress when the limit equilibrium state is reached. The expression is as follows:

[0103]

[0104] In formula (2), F s is the safety factor, τ f is the shear strength, τ is the shear stress in the limit equilibrium state;

[0105] S304: Obtaining the overall characteristic equation;

[0106] S305: Constrain each boundary, extract the parts that do not need to be considered or are excluded from influence, select a suitable solution to solve the overall equilibrium equations, and obtain the node displacement and unit stress.

[0107] S4: Compare and analyze the real-time monitoring data in the data acquisition system and the numerical simulation calculation results, analyze the changing trend of the slope, identify potential unstable areas, and use automated algorithms to update the two-dimensional numerical model in real time to complete the real-time dynamic evaluation of the slope and provide early warning of potential slope instability risks.

[0108] S401: Compare and analyze the real-time monitoring data and the numerical simulation calculation results in the data acquisition system to verify the accuracy of the two-dimensional numerical model. If the accuracy is lower than a preset value, adjust the parameters of the two-dimensional numerical model until the accuracy is not lower than the preset value;

[0109] S402: Compare the real-time monitoring data with the numerical simulation calculation results to determine the stability of the slope, analyze the change trend of the slope, and identify potential unstable areas, wherein the change trend of the slope includes but is not limited to the displacement, stress, and plastic strain of the slope;

[0110] S403: Use automated algorithms to update the two-dimensional numerical model in real time, achieve real-time dynamic assessment of the slope, and provide early warning of potential slope instability risks.

[0111] Specific implementation method two: This implementation method is explained in conjunction with the figure. As shown in the figure, the numerical simulation and stability analysis system for slope monitoring data described in this implementation method includes: a sensor module, which is used to collect slope data in real time; a data acquisition system module, which is used to monitor and record real-time data and transmit the monitoring data to the data processing and analysis module; a power supply module, which is used to provide a stable power supply for the data acquisition system module; a two-dimensional numerical model module, which is used to perform numerical simulation calculations on the slope; a data processing and analysis module, which is used to compare and analyze the numerical simulation calculation results and real-time data, evaluate the stability of the slope and issue a warning message when the warning threshold is exceeded; a user interaction module, which is used to display the monitoring data, slope stability evaluation results and numerical simulation calculation results in real time, and adjust the system parameters according to user settings.

[0112] The data processing and analysis module includes a data receiving submodule, a comparison and analysis submodule, and an early warning and reporting submodule;

[0113] The data receiving submodule is used to receive monitoring data from the data acquisition system module;

[0114] The comparative analysis module is used to compare and analyze the numerical simulation results with real-time data, evaluate the stability of the slope, and output a real-time evaluation report;

[0115] The warning and reporting submodule is used to generate stability reports based on the evaluation results and issue warning information when the warning threshold is exceeded.

[0116] The user interaction module includes a display screen and a control submodule;

[0117] The display screen is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time;

[0118] The control submodule allows the user to perform operation settings, where the operation settings include but are not limited to adjusting the monitoring frequency, setting the warning threshold, and querying historical data.

[0119] Specific implementation method three: This implementation method is described in conjunction with the figure. To verify the technical effect of the present invention, this implementation method is carried out as follows:

[0120] 1. Natural working condition analysis: This implementation method combines the bar graph and the profile graph to draw the CAD graph of the slope soil layer distribution, and simplifies the left and right boundaries to make it meet the model establishment conditions without affecting the actual stability of the slope. This implementation method is based on the distribution of the slope soil layer bar graph and the soil layer profile distribution, such as Figure 3 (a) Figure 3 (b) and Figure 3 As shown in (c), simplified CAD images of three sections of the slope are drawn. Various information of the soil layer is input into the MidasGtsNx software to establish an actual stratum model. The section is mainly divided into three main surfaces for calculation, research and analysis, and three representative surfaces are selected, namely, section CVII-CVII', section Ci-Ci', and section Cii-Cii'. The first section is 160m long and has a height difference of 45m. At the same time, the grid is generated. The important parts are tightly divided and the irrelevant parts are loosely meshed to reduce the amount of calculation. The completed section has a total of 4178 nodes and 8098 units. The second section is 145m long and has a height difference of 45m. The completed section has a total of 4442 nodes and 8617 units. The third section is 160m long and has a height difference of 45m. The completed section has 4939 nodes and 9569 units. The geotechnical parameters of each layer are selected according to Table 2, including elastic modulus, Poisson's ratio, gravity, cohesion, internal friction angle, etc. of plain fill, fully weathered granite, strongly weathered granite, and moderately weathered granite. The soil layer model selects the Moore-Coulomb constitutive model, selects appropriate soil layer parameters for each foundation, selects gravity, adds boundary conditions, constrains the slope boundary, and extracts the part of the slope that has been supported and determined not to have a large displacement to prevent the stress and strain of this part from affecting the overall stability evaluation of the slope. Then add the analysis condition, select the finite element strength reduction method, select the displacement, internal force, energy, and other analysis reference data in the analysis control, and finally perform simulation and calculation.

[0121] Table 2

[0122]

[0123] The soil profile and grid division of the slope before leveling and support are as follows: Figure 4 (a) Figure 4 (b) and Figure 4 As shown in (c), the grid at the center of the slope is relatively dense, with a triangular grid of 1m units, which is more detailed than the square grid. A triangular grid of 1.5m units is used at the slope boundary, and a smooth linear transition is set between 1m and 1.5m, so that the slope can focus on reflecting the stress, strain and displacement of the sliding zone without affecting the calculation accuracy.

[0124] The results of the two-dimensional numerical model established by the present invention are analyzed as follows: the high slope on the south side of the cooling tower is studied by using Midas GTS NX geotechnical finite element software, and the three sections of the high slope are modeled in their natural state before support using the software and the relevant parameters are input to obtain the specific stress strain and safety factor of the three sections. During the calculation process, no abnormal situation occurred that caused the calculation results to terminate or the iteration did not converge. At the same time, there was no endless slip inside the actual deformed slope, and the slope modeling was relatively normal. Moreover, the overall numerical value of the slope after calculation is relatively reasonable, without excessive displacement or deformation, and the slope sliding zone is also in the estimated position, and the model is reasonably established.

[0125] After numerical simulation, the safety factors of the first, second and third sections under natural working conditions are obtained as follows:

[0126] 1.77969, 1.2375, 4.225. Therefore, combining the slope safety factor and the slope stability state classification specification, it can be seen that Sections 1 and 3 are in a stable state, Section 3 is more stable and safer than Section 1, and Section 2 is in a basically stable state.

[0127] like Figure 5 (a) Figure 5 (b) and Figure 5As shown in (c), the plastic strain degree is large in the places where the slope of the right side of the first and second sections is relatively large. The maximum plastic strain values ​​of the two sections are 1.61 and 0.64 respectively, which are relatively normal, but the sliding surface of the second section is larger, so the safety factor is lower than that of the first section. The maximum plastic strain value of the three nodes of the section is 8.18. It mainly occurs in the plain fill layer. The overall plastic strain value is small, indicating that the slope is relatively stable, which is very related to the overall soil distribution of the slope. In the case of natural leveling and increasing the cooling tower load, the slope is small, and the sliding zone is only concentrated on the natural slope formed after artificial excavation, indicating that the overall stability of the experimental area of ​​the present invention is good.

[0128] like Figure 6 (a) Figure 6 (b) and Figure 6 As shown in (c), the upper part of the slope of Sections 1 and 2, i.e., the left side of the picture, has undergone a certain amount of settlement. The main displacement occurs on the right side of the section, with the maximum displacements of 3.61 cm and 0.64 cm respectively. The displacements of the rest of the sections are small and have not changed much. The displacement of the upper soil layer of Section 3 has changed greatly, with the maximum displacement of 20.835 cm. Figure 7 (a) Figure 7 (b) and Figure 7 (c) shows the shear force distribution of the three sections of the slope, with a minimum value of -30.4KN and a maximum value of 135.24KN. The distribution area is related to the distribution of soil layers. They all decrease from the medium-weathered rock layer to the plain fill or fully weathered granite on the slope surface, which is in line with the normal shear force distribution law of the slope. Under natural working conditions, the cooling tower slope is in a stable state as a whole, and the stability of section 2 is slightly lower. At the same time, the scientificity and feasibility of the existing support method of the slope can also be determined based on the plastic strain diagram. The 23m pile passes through the plastic strain area of ​​the slope, and the anchor cable is driven in to stabilize the slope that may change, which can well prevent problems from occurring on the slope.

[0129] 2. Support working condition analysis: Figure 8 (a) Figure 8 (b) and Figure 8As shown in (c), this embodiment draws simplified CAD images of three sections of the slope, imports MidasGtsNx, and establishes a two-dimensional numerical model. The slope calculation model has three main sections: Section CVII-CVII' is 120m long along the X direction and 40m along the Y direction. The grid distribution is dense and sparse, the important parts are relatively fine, and the unimportant parts are relatively rough. A smooth linear transition is selected between the two. There are 3297 nodes and 6466 units in total. Section Ci-Ci' is 120m long along the X direction and 37m along the Y direction, with 3051 nodes and 5983 units. Section Cii-Cii' is 122m long along the X direction and 40m along the Y direction, with 3582 nodes and 6950 units. Then, according to Table 5-1, the geotechnical parameters of each layer are selected, including the elastic modulus, Poisson's ratio, gravity, cohesion, internal friction angle, etc. of plain fill, fully weathered granite, strongly weathered granite, and moderately weathered granite. The soil layer model selects the Moore-Coulomb constitutive model, selects appropriate soil layer parameters for each foundation, selects to add gravity, adds boundary conditions, and constrains the slope boundary, that is, restricts the vertical and horizontal displacements of the bottom and side of the model. The plane where the slope surface and slope profile are located is an unrestricted plane. The horizontal load on the supporting rock layer is calculated through the weight of reinforced concrete, the structure of the cooling tower, and various factors. At the same time, the stress and strain data of the monitoring platform are added to the model to ensure the accuracy of the model. For the model, it is also necessary to add extraction settings to the places where there will be no displacement in the model, so that other stresses and strains will not occur during the computer numerical simulation process to affect the overall results. Then add analysis conditions, select the finite element strength reduction method, select displacement, internal force, energy, and other analysis reference data in the analysis control, and finally perform simulation and calculation.

[0130] The three sections of the slope on the south side of the cooling tower after pile anchor support are as follows: Fig. 9 (a) Fig. 9 (b) and Fig. 9 As shown in (c), there are mainly four soil layers, three materials, external anchor prestressing and uniformly distributed loads brought by cooling towers, and the deadweight of the soil layers. In addition, this implementation method limits the displacement changes on the left side of the slope and the lower right side, which can better display the various states of the slope support parts.

[0131] The plane plastic strain of the slope profile after support is as follows: Fig.10 (a) Fig.10 (b) and Fig.10 As shown in (c), the maximum plastic strains of sections 1, 2 and 3 are 0.79, 1.04 and 3.21 respectively, which are only distributed in a few nodes. The plastic strain values ​​of more than 90% of the nodes are less than 0.1, and the plastic deformation is within the allowable range, which is relatively safe.

[0132] The overall displacement of the slope profile after support is as follows Fig.11(a) Fig.11 (b) and Fig.11 As shown in (c), in the three sections, the settlement values ​​of the cooling tower area are 1cm, 0.6cm, and 0.5cm respectively. The maximum uplift values ​​on the right are 2.14cm, 4.08cm, and 3.21cm respectively. The values ​​are all within the normal engineering variation range, and the slope is in a safe and stable state.

[0133] The shear stress distribution of the slope profile after support is as follows: Fig.12 (a) Fig.12 (b) and Fig.12 As shown in (c), the shear stress of the slope profile is mainly distributed on the supporting piles, and the distribution in other areas is relatively stable. The maximum value of profile one is 719.74KN, and the minimum value is -432.00KN. The maximum value of profile two is 443.96KN, and the minimum value is -365.23KN. The maximum value of profile three is 401.38KN, and the minimum value is -314.35KN, which are all within the shear strength of the supporting piles. Combined with the safety factor, overall displacement, plane plastic strain and shear stress distribution of the three slope profiles after support, it can be judged that the slope meets the safety requirements and can maintain the stability of the slope well.

[0134] The comparative analysis results of the two-dimensional numerical model and monitoring data are as follows:

[0135] Displacement analysis: The displacement in the X direction of the slope profile after support is as follows: Fig.13 (a) Fig.13 (b) and Fig.13 As shown in (c), the Y-direction displacement of the slope profile after support is as follows Fig.14 (a) Fig.14 (b) and Fig.14 As shown in (c), the three sections all had certain displacements, with the maximum displacements being 1.86cm, 3.2cm and 3.2cm respectively. In the area where the cooling tower has applied loads, certain settlements occurred, with values ​​of 1.13cm, 1.81cm and 1.70cm respectively. Overall analysis shows that the displacement values ​​are within the actual deformation safety range, and the slope is in a stable state.

[0136] Support pile axial force analysis: Select the 6 nodes inside the two-dimensional numerical model, check the actual effective stress value, and obtain the model stress data in Table 3. Compared with the actual monitoring data, it is found that there is a certain gap with the actual situation, but the overall situation is relatively close, indicating that the two-dimensional numerical model established by the present invention can approximately reflect the actual slope stability changes.

[0137] Table 3

[0138]

[0139]

[0140] Specific implementation method 2: Fig.15 As shown, the numerical simulation and stability analysis system based on monitoring data described in this embodiment includes: a sensor module for collecting slope data in real time;

[0141] The data acquisition system module is used to monitor and record real-time data and transmit the monitoring data to the data processing and analysis module;

[0142] A power supply module is used to provide a stable power supply for the data acquisition system module;

[0143] Two-dimensional numerical model module, used for numerical simulation of slopes;

[0144] Data processing and analysis module, used to compare and analyze numerical simulation results and real-time data, evaluate the stability of the slope and issue warning information when the warning threshold is exceeded;

[0145] The user interaction module is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time, and adjust system parameters according to user settings.

[0146] The data processing and analysis module includes a data receiving submodule, a comparison and analysis submodule, and an early warning and reporting submodule;

[0147] The data receiving submodule is used to receive monitoring data from the data acquisition system module;

[0148] The comparative analysis module is used to compare and analyze the numerical simulation results with real-time data, evaluate the stability of the slope, and output a real-time evaluation report;

[0149] The warning and reporting submodule is used to generate stability reports based on the evaluation results and issue warning information when the warning threshold is exceeded.

[0150] The user interaction module includes a display screen and a control submodule;

[0151] The display screen is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time;

[0152] The control submodule allows the user to perform operation settings, where the operation settings include but are not limited to adjusting the monitoring frequency, setting the warning threshold, and querying historical data.

[0153] The above 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 technician familiar with this profession 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 simple modification, equivalent replacement and improvement made to the above embodiments without departing from the content of the technical solution of the present invention, based on the technical essence of the present invention, within the spirit and principles of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. Numerical simulation and stability analysis method based on monitoring data, characterized in that: The steps of the numerical simulation and stability analysis method based on monitoring data include: Step 1: Use multifunctional sensors to collect slope data in real time; Step 2: Transmit the collected data of the sensor to the data acquisition system for real-time data monitoring and recording; Step 3: Use finite element analysis software to construct a two-dimensional numerical model of the slope, analyze the slope through the two-dimensional numerical model, and obtain the numerical simulation calculation results of the slope; Step 4: Compare and analyze the real-time monitoring data in the data acquisition system and the numerical simulation calculation results, analyze the changing trend of the slope, identify potential unstable areas, and use automated algorithms to update the two-dimensional numerical model in real time to complete real-time dynamic evaluation of the slope and provide early warning of potential slope instability risks.

2. The method for numerical simulation and stability analysis based on monitoring data according to claim 1, characterized in that: In step 1, the multifunctional sensors include but are not limited to displacement sensors, stress sensors and pore water pressure gauges, and the collected slope data include but are not limited to displacement, stress, plastic strain and pore water pressure of the slope.

3. The method of numerical simulation and stability analysis based on monitoring data according to claim 1, characterized in that: The data monitoring results in step 2 include but are not limited to displacement changes on the slope surface and inside, stress changes, plastic strain areas and stress-strain relationships of the soil, and environmental data related to geology and climate change.

4. The method of numerical simulation and stability analysis based on monitoring data according to claim 1, characterized in that: The analysis of the slope by the two-dimensional numerical model in step 3 specifically includes: Input slope soil parameters into the two-dimensional numerical model for static and dynamic analysis; Through static analysis and calculation, the force distribution, displacement cloud diagram and plastic strain area of ​​the slope soil under different working conditions are obtained; Through dynamic analysis, the Moore-Coulomb criterion is used to simulate the instability and landslide behavior of the slope under the action of external forces and environmental changes, and the slope is dynamically analyzed to evaluate the stability of the slope.

5. The method for numerical simulation and stability analysis based on monitoring data according to claim 4, characterized in that: The steps of kinetic analysis include: Step 3.1: Divide the slope rock mass into finite element units; Step 3.2: Determine the node displacement mode so that the displacement function at the node is equal to the node displacement and meets the convergence criterion; Step 3.3: Calculate the stiffness matrix between the node displacement and element strain in the slope element; Step 3.4: Obtain the overall characteristic equation of the slope based on the stiffness matrix between the node displacement and the element strain; Step 3.5: Constrain the boundaries of the finite element units of the slope, extract the unit parts that are excluded from the influence, and solve the overall characteristic equation of the slope to complete the dynamic analysis and obtain the node displacement and unit stress.

6. The method for numerical simulation and stability analysis based on monitoring data according to claim 5, characterized in that: Step 3.3 specifically includes: Step 3.3.1: Obtain the shear strength of any point in the finite element unit through the cohesion, shear stress and internal friction angle of the slope rock and soil; Step 3.3.2: The safety factor of any point in the finite element unit is calculated by using the shear strength and shear stress and the Mohr-Coulomb yield criterion; Step 3.3.3: Perform strength reduction process based on the shear strength and safety factor of the corresponding points to obtain the stiffness matrix between the node displacement and unit strain in the slope unit.

7. The method for numerical simulation and stability analysis based on monitoring data according to claim 1, characterized in that: Step 4 specifically includes: Compare and analyze the real-time monitoring data in the data acquisition system and the numerical simulation calculation results to verify the accuracy of the two-dimensional numerical model. If the accuracy is lower than the preset value, adjust the parameters of the two-dimensional numerical model until the accuracy is not lower than the preset value; By comparing the real-time monitoring data with the numerical simulation calculation results, the stability of the slope is judged, the change trend of the slope is analyzed, and the potential unstable area is identified. The change trend of the slope includes but is not limited to the displacement, stress, and plastic strain of the slope; An automated algorithm is used to update the two-dimensional numerical model in real time, enabling real-time dynamic assessment of the slope and early warning of potential slope instability risks.

8. A numerical simulation and stability analysis system based on monitoring data, applied to the numerical simulation and stability analysis method based on monitoring data according to any one of claims 1 to 7, characterized in that: include: Sensor module, used to collect slope data in real time; The data acquisition system module is used to monitor and record real-time data and transmit the monitoring data to the data processing and analysis module; A power supply module is used to provide a stable power supply for the data acquisition system module; Two-dimensional numerical model module, used for numerical simulation of slopes; Data processing and analysis module, used to compare and analyze numerical simulation results and real-time data, evaluate the stability of the slope and issue warning information when the warning threshold is exceeded; The user interaction module is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time, and adjust system parameters according to user settings.

9. The numerical simulation and stability analysis system based on monitoring data according to claim 8, characterized in that: The data processing and analysis module includes a data receiving submodule, a comparison and analysis submodule, and an early warning and reporting submodule; The data receiving submodule is used to receive monitoring data from the data acquisition system module; The comparative analysis module is used to compare and analyze the numerical simulation results with real-time data, evaluate the stability of the slope, and output a real-time evaluation report; The warning and reporting submodule is used to generate stability reports based on the evaluation results and issue warning information when the warning threshold is exceeded.

10. The numerical simulation and stability analysis system based on monitoring data according to claim 8, characterized in that: The user interaction module includes a display screen and a control submodule; The display screen is used to display monitoring data, slope stability assessment results and numerical simulation calculation results in real time; The control submodule allows the user to perform operation settings, where the operation settings include but are not limited to adjusting the monitoring frequency, setting the warning threshold, and querying historical data.

Images