A method and system for early warning of water conservancy facility safety

Abstract

This invention provides a method and system for early warning of water conservancy facility safety, relating to the field of water conservancy facility safety technology. The method includes collecting water conservancy project parameters, hydrological data, and structural parameters of the water conservancy facility; constructing a hydrodynamic mathematical model and performing stress analysis to obtain dynamic water pressure distribution data; screening areas of concentrated impact force, drawing pressure contour maps to locate high-risk areas, and identifying key areas of concern; implementing rebound strength testing to obtain actual compressive strength values; constructing a pressure model, calculating the theoretical deformation curve of the gate, and obtaining actual deformation data through laser ranging; and establishing a multi-level safety early warning index system for safety warning. This invention, through multi-disciplinary model fusion, multi-source data collaboration, and a dynamic early warning mechanism, achieves accurate identification and efficient early warning of water conservancy facility safety risks, providing strong technical support for the safe operation and maintenance of water conservancy facilities under complex operating conditions.

Description

Technical Field

[0001] This invention relates to the field of water conservancy facility safety technology, and in particular to a water conservancy facility safety early warning method and a water conservancy facility safety early warning system. Background Technology

[0002] As core projects for water resource regulation, flood control and disaster reduction, the safe and stable operation of water conservancy facilities is directly related to the safety of people's lives and property and social and economic development.

[0003] However, the current field of early warning for water conservancy facilities still faces numerous technical bottlenecks, making it difficult to meet the demand for accurate early warning under complex operating conditions. Existing early warning methods largely rely on manual inspections and single-point monitoring, which suffer from limited coverage, data lag, and difficulty in capturing full-range characteristics. Especially under conditions of high water levels and strong currents, data errors are significant, easily leading to delayed or false alarms. Furthermore, the scientific rigor of the early warning indicator system needs improvement. Existing methods often use fixed thresholds to assess risk, failing to consider factors such as structural nonlinear behavior, resulting in low early warning accuracy. Summary of the Invention

[0004] This invention provides a method and system for early warning of water conservancy facility safety, in order to overcome the deficiencies in the existing technology.

[0005] On the one hand, the present invention provides a method for early warning of safety of water conservancy facilities, including:

[0006] Collect parameters of water conservancy projects, hydrological data, and structural parameters of water conservancy facilities. The structural parameters of water conservancy facilities include the grade parameters of concrete dams and the material specifications of gates.

[0007] Based on the parameters of water conservancy projects and hydrological data, a hydrodynamic mathematical model based on the principles of fluid mechanics is constructed. The finite element method is used to analyze the stress on the structure of water conservancy facilities and obtain dynamic water pressure distribution data.

[0008] Based on dynamic water pressure distribution data, areas with concentrated impact force are screened, and pressure contour maps are drawn to locate high-risk areas, thus identifying key areas of concern.

[0009] The rebound strength test was carried out on key areas of concern. The surface hardness data of the concrete was recorded and converted to obtain the actual compressive strength value.

[0010] Based on the gate material specifications, a stamping model is constructed, the theoretical deformation curve of the gate is calculated, and the actual deformation data is obtained through laser ranging.

[0011] By comparing the actual compressive strength values ​​with dynamic water pressure distribution data and analyzing the deviation between the actual deformation data and the theoretical deformation curve, a multi-level safety early warning indicator system is established.

[0012] When the detected value exceeds the safety threshold, an alert is triggered, and an assessment report containing the location and extent of the risk is generated.

[0013] According to the present invention, a method for early warning of safety of water conservancy facilities is provided, wherein hydrological data includes water level, flow velocity, pressure, and temperature. Water conservancy engineering parameters include reservoir capacity and dam geometry, wherein dam geometry includes height, slope, and crest width.

[0014] According to the present invention, a method for early warning of water conservancy facility safety includes the following process for constructing a hydrodynamic mathematical model based on fluid mechanics principles:

[0015] The area where the water conservancy facilities are located is divided into three-dimensional spaces to form a three-dimensional computational grid, thereby obtaining the boundary range of the water area and the water conservancy facilities.

[0016] Based on the Navier-Stokes equations and the continuity equation, and combined with hydraulic engineering parameters and hydraulic facility structural parameters, initial and boundary conditions are set. The initial conditions represent the flow state parameters, while the boundary conditions are the flow parameter constraints within the boundary range of the water area and the hydraulic facility. The flow state parameters include flow velocity magnitude, flow direction, flow pressure, and flow density. The flow parameter constraints include velocity limits, pressure limits, and flow rate limits at the boundaries.

[0017] The Navier-Stokes equations and continuity equations are discretized using the finite volume method, transforming continuous water flow motion into numerical calculations at discrete nodes. Dynamic numerical simulation of continuous water flow motion is then performed to obtain a hydrodynamic mathematical model.

[0018] According to the present invention, a method for early warning of water conservancy facility safety includes the following process for obtaining dynamic water pressure distribution data:

[0019] A finite element model of the water conservancy facility structure is constructed, including the concrete dam body and gates.

[0020] The hydraulic load is calculated based on the hydrodynamic mathematical model and applied to the finite element model in the form of nodal forces.

[0021] Based on the structural parameters of the water conservancy facility, the material constitutive relationship of the finite element model is defined, the stress concentration factor of the water conservancy facility structure is calculated, and the load combination is formed by combining the water pressure load.

[0022] By combining load combinations, the stress field and displacement field of the finite element model in the hydrodynamic mathematical model are solved by time history analysis to obtain dynamic water pressure distribution data.

[0023] According to the present invention, a method for early warning of water conservancy facility safety includes the following process for screening areas of concentrated impact force:

[0024] Based on dynamic water pressure distribution data, the dynamic water pressure gradient on the surface of the hydraulic facility structure is calculated, and the area of ​​the hydraulic facility structure surface where the dynamic water pressure gradient exceeds a preset threshold is marked as a potential impact force concentration area.

[0025] According to the water conservancy facility safety early warning method provided by the present invention, the process of obtaining the key concern area includes:

[0026] Dynamic water pressure distribution data is interpolated onto a regular grid to form a continuous pressure data distribution.

[0027] The Kriging interpolation algorithm is used to process the continuous pressure data distribution to generate a continuous pressure field.

[0028] A pressure contour map is generated by plotting closed curves of a continuous pressure field based on pressure values ​​at equal intervals.

[0029] Identify areas of dense contour lines and high-value areas in the pressure contour map, and mark key areas of interest based on the stress concentration factor.

[0030] According to the present invention, a method for early warning of water conservancy facility safety includes the following steps in obtaining the actual compressive strength value:

[0031] Select measurement areas within the key areas of focus, and evenly distribute N measurement points in each measurement area.

[0032] Use a standard rebound hammer perpendicular to the concrete surface to conduct the test and record the rebound value at each test point.

[0033] After removing outlier data, the average rebound value of the test area is calculated. Outlier data includes anomalies in carbonization depth.

[0034] The carbonation depth of concrete was measured, and the thickness of the carbonation layer was determined using the phenolphthalein reagent colorimetric method.

[0035] The compressive strength of concrete is obtained by comparing the average rebound value of the test area with the carbonation depth of the concrete and converting the values ​​using the strength test curve.

[0036] According to the water conservancy facility safety early warning method provided by the present invention, the process of constructing a stamping model based on the gate material specifications includes:

[0037] Determine the geometric parameters and load conditions of the gate. The geometric parameters include length, width, thickness and support method, and the load conditions include hydrostatic pressure, hydrodynamic pressure and wave load.

[0038] Select the material constitutive model that matches the gate material, and set the gate's material parameters, including elastic modulus, Poisson's ratio, yield strength, and ultimate strength.

[0039] Define the contact conditions of the gate, which include the frictional contact between the gate and the gate slot.

[0040] By applying boundary constraints and load distribution, the stress state of the gate under different working conditions is simulated, and a stamping model based on the gate material specifications is constructed.

[0041] According to the present invention, a method for early warning of safety of water conservancy facilities includes the following process for calculating the theoretical deformation curve of a gate:

[0042] Based on the principles of mechanics of materials and combined with the stamping model, the deflection differential equation of the gate under water pressure is established.

[0043] Considering the constraints and load distribution of the gate, the deflection differential equation is solved using the two-moment theory. The constraints include simply supported and fixed supports, and the load distribution includes uniformly distributed loads and concentrated loads.

[0044] Based on the solution results, the maximum deflection and stress distribution of the gate at different water levels are calculated.

[0045] The influence of the nonlinear behavior of the gate on its deformation is analyzed. The nonlinear behavior includes the large deformation effect.

[0046] Based on the calculation results at different water levels, theoretical deformation curves of the gate under different operating conditions are generated.

[0047] On the other hand, the present invention also provides a water conservancy facility safety early warning system, comprising:

[0048] The data acquisition module is used to collect parameters of water conservancy projects, hydrological data, and structural parameters of water conservancy facilities. The structural parameters of water conservancy facilities include the grade parameters of concrete dams and the material specifications of gates.

[0049] The water pressure distribution calculation module is used to construct a hydrodynamic mathematical model based on fluid mechanics principles according to water conservancy project parameters and hydrological data, and to perform stress analysis on the structure of water conservancy facilities using the finite element method to obtain dynamic water pressure distribution data.

[0050] The key area screening module is used to screen areas with concentrated impact force based on dynamic water pressure distribution data, draw pressure contour maps to locate high-risk areas, and obtain key areas of concern.

[0051] The compressive strength calculation module is used to perform rebound strength testing on key areas of interest, record concrete surface hardness data, and perform conversions to obtain the actual compressive strength value.

[0052] The deformation data acquisition module is used to construct a stamping model based on the gate material specifications, calculate the theoretical deformation curve of the gate, and acquire actual deformation data through laser ranging.

[0053] The comparison and early warning module is used to compare the actual compressive strength value with the dynamic water pressure distribution data, analyze the deviation between the actual deformation data and the theoretical deformation curve, establish a multi-level safety early warning index system, trigger an early warning when the detected value exceeds the safety threshold, and generate an assessment report that includes the location and degree of risk.

[0054] This invention provides a method and system for early warning of water conservancy facility safety. By integrating hydrodynamic mathematical models and finite element structural analysis, it achieves a dynamic correlation between water flow loads and structural responses. Through three-dimensional computational mesh generation and Kriging interpolation, it accurately characterizes the distribution characteristics of water pressure on the surface of the water conservancy facility, and identifies high-risk areas by combining stress concentration factors, overcoming the limitations of traditional single-point monitoring. A complete closed loop for early warning of water conservancy facility safety is constructed, with water conservancy engineering parameters, hydrological data, and structural parameters as the core. By discretizing fluid dynamics equations using the finite volume method, hydrological data is transformed into dynamic loads that can be directly applied to the structural model; and non-destructive testing of concrete strength and gate deformation is achieved using the rebound method and laser ranging technology. Attached Figure Description

[0055] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0056] Figure 1 This is a flowchart illustrating a water conservancy facility safety early warning method provided in an embodiment of the present invention;

[0057] Figure 2 This is a schematic diagram of the structure of a water conservancy facility safety early warning system provided in an embodiment of the present invention. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0059] The following is combined Figures 1-2 This invention describes a method and system for early warning of safety in water conservancy facilities.

[0060] Figure 1 This is a flowchart illustrating a water conservancy facility safety early warning method provided in an embodiment of the present invention.

[0061] like Figure 1 As shown in the embodiment of the present invention, a method and system for early warning of water conservancy facility safety are provided. The executing entity can be a method for early warning of water conservancy facility safety, which includes:

[0062] Collect parameters of water conservancy projects, hydrological data, and structural parameters of water conservancy facilities. The structural parameters of water conservancy facilities include the grade parameters of concrete dams and the material specifications of gates.

[0063] Hydrological data includes water level, flow velocity, pressure, and temperature. Hydraulic engineering parameters include reservoir capacity and dam geometry, with dam geometry including height, slope, and crest width.

[0064] Collection of structural parameters for water conservancy facilities: Focusing on two core structures, concrete dams and gates. The grade parameters of concrete dams need to be obtained by reviewing construction archives and conducting on-site sampling and testing, including the concrete design strength grade (e.g., C25, C30), impermeability grade (e.g., P6, P8), and modulus of elasticity. For gates, the material specifications need to be recorded, including the main material (e.g., carbon steel Q235, stainless steel 304), thickness, and welding process parameters, to ensure that the parameters cover the key stress attributes of the structure.

[0065] Hydrological data acquisition: A combination of automated monitoring equipment and manual inspection is used to collect four types of data: water level, flow velocity, pressure, and temperature. Water level is monitored in real time using ultrasonic level gauges deployed at different elevations on the dam body, with a sampling frequency of once every 5 minutes and an accuracy controlled within ±0.01m. Flow velocity is obtained by using Doppler current meters with three monitoring points evenly distributed across the water cross-section to obtain the average flow velocity of the cross-section, with an error not exceeding 5%. Pressure is collected by pressure sensors buried on the upstream side of the dam body, covering the water level fluctuation zone and key parts of the dam bottom. Temperature is monitored by thermocouple sensors to monitor the water body and dam surface temperature, and the data is synchronously transmitted to the central control system.

[0066] Hydraulic engineering parameter acquisition: The focus is on acquiring reservoir capacity and dam geometry. Reservoir capacity is obtained through a reservoir capacity curve, which is generated from the dam's as-built measurement data and covers the entire range from dead water level to check flood level. Dam geometry is obtained through on-site measurements using a total station, including dam height (vertical distance from dam crest to dam base), slope (ratio of vertical height to horizontal distance of dam slope), and crest width (horizontal width at the dam crest centerline). Measurement errors are controlled within ±0.05m to ensure the geometric accuracy of subsequent model construction.

[0067] Based on the parameters of water conservancy projects and hydrological data, a hydrodynamic mathematical model based on the principles of fluid mechanics is constructed. The finite element method is used to analyze the stress on the structure of water conservancy facilities and obtain dynamic water pressure distribution data.

[0068] The process of constructing a hydrodynamic mathematical model based on fluid dynamics principles includes:

[0069] The area where the water conservancy facilities are located is divided into three-dimensional spaces to form a three-dimensional computational grid, thereby obtaining the boundary range of the water area and the water conservancy facilities.

[0070] An unstructured mesh was used to divide the area where the water conservancy facilities were located into three dimensions. The mesh cell type was tetrahedral, and the size was dynamically adjusted according to the complexity of the structure. The mesh size was set to 0.5m×0.5m×0.5m on the surface of the dam body, gate and other structures, and the mesh size was enlarged to 5m×5m×5m in the open water area. The stability of the calculation was ensured by checking the mesh quality (twist rate <0.8). Finally, the boundary range of the water area and water conservancy facilities was obtained. The boundary line was fitted to the actual terrain using a polyline.

[0071] Based on the Navier-Stokes equations and the continuity equation, and combined with hydraulic engineering parameters and hydraulic facility structural parameters, initial and boundary conditions are set. Initial conditions represent flow state parameters, while boundary conditions are flow parameter constraints within the boundaries of the water area and hydraulic facilities. Flow state parameters include flow velocity magnitude, flow direction, flow pressure, and flow density. Flow parameter constraints include velocity, pressure, and flow rate limits at the boundaries. Specifically, the inlet boundary is set as a flow rate boundary (determined by the inflow rate from hydrological data), the outlet boundary is set as free outflow, the solid wall boundary (dam body, gate surface) is set as a no-slip condition (velocity limit of 0), the pressure limit is taken as the local atmospheric pressure, and the flow rate limit is set with an upper limit based on the flood discharge capacity.

[0072] The Navier-Stokes equations are used to describe the motion of fluids, and the formulas are expressed as follows:

[0073]

[0074] The continuity equation is used to describe the law of conservation of mass in fluids, and the formula is expressed as:

[0075]

[0076] In the formula, This indicates the density of water. Let p represent the velocity vector and p represent the pressure. Represents the fluid dynamic viscosity coefficient. It represents volume force.

[0077] The Navier-Stokes equations and continuity equations are discretized using the finite volume method, transforming continuous water flow motion into numerical calculations at discrete nodes. Dynamic numerical simulation of continuous water flow motion is then performed to obtain a hydrodynamic mathematical model.

[0078] The computational domain is divided into a series of control volumes. For each control volume integral equation, the volume integral is transformed into a surface integral using Gauss's theorem, resulting in a discrete equation, expressed as:

[0079]

[0080] In the formula, This indicates the throughput of the control interface. V represents the density of water, and V is the volume of the control volume.

[0081] The convection term is calculated using a first-order upwind scheme, the diffusion term is calculated using a central difference scheme, and the pressure-velocity coupling problem is solved using the SIMPLE algorithm with a time step of 0.1 s. The continuous water flow motion is dynamically simulated and iterated until convergence is achieved, finally obtaining a hydrodynamic mathematical model that can output the water flow pressure and velocity distribution at any time.

[0082] The process of obtaining dynamic water pressure distribution data includes:

[0083] A finite element model of the water conservancy facility structure is constructed, including the concrete dam body and gates.

[0084] Based on the structural parameters of the hydraulic facilities, a finite element model including a concrete dam and gates was constructed using ANSYS software. The concrete dam was modeled using solid elements (SOLID65) with element sizes of 1m×1m×1m, taking into account the material properties differences caused by the layered casting of the dam. The gates were modeled using shell elements (SHELL181) with element thickness consistent with the actual gate thickness (e.g., 0.05m). The model had approximately 500,000 nodes to ensure that structural details (such as dam galleries and gate supports) were accurately represented.

[0085] The water pressure load is calculated based on the hydrodynamic mathematical model and applied to the upstream nodes of the finite element model in the form of nodal forces according to the time sequence. The load magnitude is dynamically updated as the water level changes.

[0086] The material constitutive relations of the finite element model are defined based on the structural parameters of the water conservancy facility.

[0087] The concrete dam body adopts an elastoplastic model, and its constitutive relation is as follows:

[0088]

[0089] In the formula, For stress, The elastic modulus of the concrete dam body. For total strain, For plastic strain; the gate adopts a linear elastic model, and the constitutive relation is as follows: E take Poisson's ratio is 0.3.

[0090] The stress concentration factor of the hydraulic facility structure is calculated. The stress concentration factor is obtained by the ratio of the maximum stress to the nominal stress in the finite element model. This is then combined with the hydraulic pressure load to form a load combination.

[0091] By combining load combinations, the stress field and displacement field of the finite element model in the hydrodynamic mathematical model are solved by time history analysis to obtain dynamic water pressure distribution data.

[0092] Based on dynamic water pressure distribution data, areas with concentrated impact force are screened, and pressure contour maps are drawn to locate high-risk areas, thus identifying key areas of concern.

[0093] The process of screening areas of concentrated impact includes:

[0094] Based on dynamic water pressure distribution data, the dynamic water pressure gradient on the surface of the hydraulic facility structure is calculated, and the area of ​​the hydraulic facility structure surface where the dynamic water pressure gradient exceeds a preset threshold is marked as a potential impact force concentration area.

[0095] Based on dynamic water pressure distribution data, the water pressure values ​​at each node on the surface of the hydraulic facility structure are extracted, and the dynamic water pressure gradient is calculated using the spatial finite difference method. Specifically, in a three-dimensional coordinate system, for the water pressure value p(x,y,z) at any node (x,y,z), the partial derivatives in the x, y, and z directions are calculated respectively. Then, the hydrodynamic pressure gradient G at that node is obtained through vector synthesis, and the calculation formula is as follows:

[0096]

[0097] The partial derivative is calculated by the ratio of the water pressure difference between adjacent nodes to the spatial distance.

[0098] A preset dynamic water pressure gradient threshold is set, which is determined based on the allowable stress of materials in the structural parameters of the hydraulic facility: for concrete dams, combined with their grade parameters (such as the axial compressive strength of C30 concrete of 20.1 MPa), a safety factor of 1.5 is taken, and the gradient threshold is calculated to be 500 Pa / m; for gates, based on their material specifications (such as the yield strength of Q235 steel of 235 MPa), a safety factor of 2.0 is taken, and the gradient threshold is set to 800 Pa / m.

[0099] Areas on the surface of hydraulic structures where the hydrodynamic pressure gradient G exceeds the corresponding threshold are marked as areas of concentrated potential impact force.

[0100] By calling the flow field data output from the hydrodynamic mathematical model, the flow regime in the potential impact force concentration area is analyzed:

[0101] If a vortex exists in the area, the area is prone to local high pressure due to the impact of the vortex, and it is included in the screening results;

[0102] If the area is located on the jet path (the angle between the flow direction and the structure surface is <30°, and the flow velocity is >2m / s), the jet impact force will intensify the stress on the structure and will be included in the screening results.

[0103] Based on the above analysis, the region of concentrated impact force was finally determined. This region must simultaneously meet two conditions: the hydrodynamic pressure gradient exceeds the threshold and a strong impact flow state exists.

[0104] The process of identifying key areas of focus includes:

[0105] Dynamic water pressure distribution data is interpolated onto a regular grid to form a continuous pressure data distribution.

[0106] The grid size is set to 1m×1m, which is determined based on the dam geometry in the hydraulic engineering parameters (e.g., when the top width of the dam is 10m, the grid size is 1 / 10 of the top width to ensure accuracy). Linear interpolation is used to fill the blank points in the grid. For nodes in the area of ​​concentrated impact force, the interpolation weight is increased by 20% to highlight their pressure characteristics, ultimately forming a continuous pressure data distribution covering the entire surface of the hydraulic facility.

[0107] The Kriging interpolation algorithm is used to process the continuous pressure data distribution to generate a continuous pressure field.

[0108] Choose a spherical variogram (suitable for the pressure attenuation with distance in hydraulic engineering), and set the range to 5m (determined based on 1 / 10 of the dam height).

[0109] By adjusting the interpolation parameters through cross-validation, we ensure that the interpolation error is less than 5% (i.e., the deviation between the interpolation result and the original dynamic water pressure data is less than 5%), and finally obtain a smooth and realistic continuous pressure field that can fully reflect the gradual change characteristics of water pressure in space.

[0110] A pressure contour map is generated by plotting closed curves of a continuous pressure field based on pressure values ​​at equal intervals.

[0111] The pressure values ​​at equal intervals are determined based on the range of dynamic water pressure distribution data. If the water pressure range is 0~10000Pa, then each interval is set at 1000Pa to ensure that the contour density of high-pressure areas (such as areas with concentrated impact force) is sufficient.

[0112] The contour3 function in MATLAB software is used to draw a three-dimensional contour map. The color gradient of the contour lines corresponds to the pressure value (blue for low pressure and red for high pressure), and the line density reflects the rate of pressure change, providing an intuitive basis for subsequent feature recognition.

[0113] Identify areas of dense contour lines and high-value areas in the pressure contour map, and mark key areas of interest based on the stress concentration factor.

[0114] Dense contour lines: The contour line spacing in this area is <2m, corresponding to a pressure gradient >500Pa / m (consistent with the gradient threshold of the impact force concentration area), indicating that the pressure changes drastically over a short distance, which can easily lead to local stress concentration;

[0115] High-value areas: The water pressure value in this area is greater than 1.2 times the design value (the design value is determined according to the flood control level in the water conservancy project parameters, such as the design water pressure corresponding to a once-in-a-century flood), and it must contain at least 5 continuous grid points to avoid interference from single-point outliers.

[0116] Based on the calculated stress concentration factor K of the hydraulic facility structure t A second screening is performed on the above-mentioned feature regions:

[0117] For areas with dense contour lines, if the K of the corresponding structural parts (such as dam corners, gate support points) t If the value is greater than 2.0 (according to the finite element analysis results, this value is the critical value for structural failure), it is marked as a high-risk candidate area;

[0118] For high-value areas, if they overlap with areas of concentrated impact force, and the K value of the overlapping area is... t If the value is greater than 1.5, it is marked as a high-risk candidate area.

[0119] By combining the two candidate areas, their intersection is selected as the final key focus area. This area must simultaneously meet three conditions: significant pressure characteristics, structural stress concentration, and strong water flow impact, thus identifying the target for subsequent concrete strength testing and gate deformation analysis.

[0120] Rebound strength testing was conducted on key areas of concern. Concrete surface hardness data was recorded and converted to obtain the actual compressive strength value. The process included:

[0121] Select measurement areas within the key areas of focus, and evenly distribute N measurement points in each measurement area.

[0122] Use a standard rebound hammer perpendicular to the concrete surface to conduct the test and record the rebound value at each test point.

[0123] After removing outlier data, the average rebound value of the test area is calculated. Outlier data includes anomalies in carbonization depth.

[0124] The carbonation depth of concrete was measured, and the thickness of the carbonation layer was determined using the phenolphthalein reagent colorimetric method.

[0125] The compressive strength of concrete is obtained by comparing the average rebound value of the test area with the carbonation depth of the concrete and converting the values ​​using the strength test curve.

[0126] When there is a difference between the structural conditions and the applicable conditions of the strength measurement curve, the core sampling method is used to correct the converted compressive strength.

[0127] In this embodiment, 16 rebound points are set up in each test area, and a ZC3-A type rebound hammer is used for testing. During the test, the rebound hammer should always be perpendicular to the test surface and should not be used to strike pores or stones. If it has struck pores or stones, the number should not be included in the 16 points of each test area. Eight points are struck on each of the two test surfaces in each test area. If there is only one test surface in a test area, 16 points need to be tested. Only one strike is allowed on the same test point. The test points should be evenly distributed within the test surface area. The rebound value reading of each test point should be accurate to 1. The distance between points should generally not be less than 20mm, and the distance between the test point and the edge of the component or exposed reinforcing bars or iron parts should generally not be less than 50mm. When testing with the rebound hammer, the instrument should preferably be in a horizontal position, testing the side of the concrete pouring direction. If this requirement cannot be met, the test can also be conducted in a non-horizontal position, or on the top or bottom surface of the concrete pouring direction.

[0128] When using a rebound hammer to test the side of a poured concrete in the horizontal direction, the three highest and three lowest rebound values ​​should be removed from the 16 rebound values ​​for each test area. The arithmetic mean of the remaining 10 rebound values ​​should be taken as the average rebound value for that test area, rounded to one decimal place. The calculation formula is as follows:

[0129]

[0130] In the formula, This represents the average rebound value of the test area, calculated to the nearest 0.1. This represents the rebound value at the i-th measuring point.

[0131] Since the rebound strength curve is calculated based on test data from horizontal tests of the concrete specimen's side surface using a rebound hammer, the measured rebound value needs to be corrected when the above conditions cannot be met during testing. First, the average rebound value of the test area is calculated from the data obtained when testing the concrete pouring side surface in a non-horizontal direction. Then, the rebound value is adjusted based on the angle between the rebound hammer axis and the horizontal force direction. Find its correction value and then convert it into the average rebound value of the test area during the horizontal test.

[0132]

[0133] In the formula, This represents the average rebound value of the test area when the rebound hammer axis is at an angle to the horizontal force direction, calculated to 0.1; Indicates different test angles The rebound correction value is calculated to 0.1.

[0134] When the rebound hammer is used to test the surface or bottom of a concrete pouring in the horizontal direction, the average rebound value of the test area should be calculated from the measured data and then corrected according to the following formula.

[0135]

[0136] In the formula, This indicates the average rebound value of the test area when inspecting the surface or bottom of a concrete pouring in the horizontal direction. This represents the rebound value correction for different pouring surfaces, calculated to 0.1.

[0137] If the instrument is not horizontal and the test area is not the side of the concrete pouring area during the test, the rebound value should be corrected for the angle first, and then the pouring surface should be corrected.

[0138] After the rebound value is measured, the carbonization depth should be measured at representative locations. The number of measuring points should not be less than 30% of the total number of measuring areas of the component, and the average value should be taken as the carbonization depth value of each measuring area of ​​the component. When the range of carbonization depth values ​​is greater than 2.0 mm, the carbonization depth value should be measured in every measuring area.

[0139] According to the Technical Specification for Testing the Compressive Strength of Concrete by Rebound Method (JGJ / T23-2011), the estimated value of the concrete strength of a component shall be determined by the following method.

[0140] When the number of test areas for a structure or component is less than 10:

[0141]

[0142] In the formula, This indicates the estimated concrete strength of the component. This represents the minimum converted value of the concrete strength in the test area of ​​the component.

[0143] When any of the strength values ​​in the test area of ​​a structure or component is less than 10.0: .

[0144] When the number of test areas for a structure or component is not less than 10 or when testing is done in batches, the following formula should be used for calculation:

[0145]

[0146]

[0147]

[0148] In the formula, This indicates the converted value of concrete strength in the component's test area. This represents the average value (MPa) of the converted concrete strength of the component's test area. The standard deviation (MPa) represents the converted value of concrete strength in the component test area, and n represents the number of test areas for the structure or component.

[0149] For components tested in batches, if the standard deviation of the concrete strength of the batch of components falls under any of the following conditions, then all components should be tested as individual components:

[0150] When the average concrete strength of this batch of components is less than 25 MPa: ;

[0151] When the average concrete strength of this batch of components is not less than 25 MPa: .

[0152] During the inspection, gate piers and other components are treated as a single component. Core samples are taken, generally to a depth not exceeding 20cm. When drilling, the drilling rig is moved to the core sampling location, placed securely, and leveled. Water and power are then connected, and the motor is started. The pressure handle is then operated to slowly bring the drill bit into contact with the concrete surface. Special care should be taken when drilling on uneven surfaces. Once the drill bit is stable in the groove, appropriate pressure can be applied for further drilling. Cooling water should be kept flowing continuously during drilling, with a flow rate of 3-5L / min. When the drill bit reaches the required length for the core sample, it is withdrawn to a distance of 20-30mm from the concrete surface. Power and water are then stopped, and the drill bit is completely withdrawn from the concrete surface. After removing the drilling rig, an arc-shaped steel chisel with a tip is inserted into the annular groove of the core sample. The end of the chisel is struck with a hammer. Due to the bending moment, the bottom of the core sample breaks off from the component. The core sample is then removed, numbered promptly, its appearance quality is checked, records are made, and it is properly stored for future testing.

[0153] After being processed and cut into cylindrical test blocks indoors, the core samples were air-dried and then subjected to compressive strength tests. The core samples were processed and cut into standard cylindrical test blocks of φ100mm×100mm indoors, and the ends were ground flat. The failure load of the core samples was then measured on a press.

[0154] The formula for converting the strength of core specimens is as follows:

[0155]

[0156] In the formula, The value represents the converted concrete strength of the core specimen (MPa), accurate to 0.1MPa; F represents the maximum pressure (N) of the core specimen in the compressive strength test. This indicates the average diameter (mm) of the core sample block.

[0157] According to the specifications, the minimum strength of the core samples within a group is taken as the representative compressive strength value of that group of core samples. This value is equivalent to the compressive strength of a standard 150cm×150cm×150cm specimen of the same age. When correcting the compressive strength of the core sample specimens for strength tested by the rebound method or other methods, there should be no fewer than 6 converted strength values ​​for standard-sized core sample specimens, and the number of small-diameter core samples should be appropriately increased. Core samples should be randomly selected from structural components using indirect testing methods. When the indirect testing method used is a non-destructive testing method, the core drilling location should coincide with the corresponding test area of ​​the indirect testing method.

[0158] Based on the gate material specifications, a stamping model is constructed, the theoretical deformation curve of the gate is calculated, and the actual deformation data is obtained through laser ranging.

[0159] The process of constructing a stamping model based on the gate material specifications includes:

[0160] Determine the geometric parameters and load conditions of the gate. The geometric parameters include length, width, thickness and support method, and the load conditions include hydrostatic pressure, hydrodynamic pressure and wave load.

[0161] The gate was scanned in three dimensions using a total station to obtain key parameters such as length, width, and thickness: the length is the maximum dimension of the gate along the water flow direction (accurate to 0.01m), the width is the span of the gate perpendicular to the water flow direction (such as the arc length projection of an arc gate), and the thickness is the actual thickness of the gate panel (the average of 3 measuring points). The support method was determined through on-site investigation and was divided into simply supported (only vertical displacement is restricted at both ends of the gate) and fixed supported (displacement and rotation are restricted at both ends of the gate). The position coordinates of the support points (distance relative to the edge of the gate) were recorded.

[0162] The hydrostatic pressure is calculated based on the collected water level data, according to the formula. Calculate, where, Represents hydrostatic pressure. Let ρ be the water density, g be the gravitational acceleration, and h be the vertical distance from the calculation point to the water surface, which are linearly distributed along the height of the gate. The dynamic water pressure is extracted from the dynamic water pressure distribution data, and the dynamic water pressure values ​​of each node on the gate surface are organized into a load curve that varies with the water flow velocity according to the time series.

[0163] Select the material constitutive model that matches the gate material, and set the gate's material parameters, including elastic modulus, Poisson's ratio, yield strength, and ultimate strength.

[0164] Select the corresponding constitutive model according to the gate material specifications: if it is carbon steel (such as Q235), use the ideal elastic-plastic model (satisfies Hooke's law before yielding and the stress remains constant after yielding); if it is stainless steel (such as 304), use the kinematic hardening model (considering the translation of the yield surface under cyclic loading).

[0165] The elastic modulus is obtained through material mechanical property testing; for carbon steel, it is taken as... Stainless steel The error is controlled within ±5%; Poisson's ratio is obtained from the gate material manual, and is usually taken as 0.3 for metal materials; the yield strength and ultimate strength are determined according to the material specification, such as the yield strength of Q235 steel is 235MPa and the ultimate strength is 375 to 500MPa, and the test temperature (value at room temperature of 20℃) is recorded.

[0166] Define the contact conditions of the gate, which include the frictional contact between the gate and the gate slot.

[0167] The contact relationship between the gate and the gate slot is defined using contact elements in finite element software. The contact type is Coulomb friction contact, and the friction coefficient is determined according to the gate material (0.15~0.2 for steel-to-steel contact, and 0.05~0.1 for surface lubrication). The contact stiffness is set to 1 / 10 of the material's elastic modulus (to avoid calculation convergence problems).

[0168] Constraints are applied according to the support method: the simply supported end restricts the displacement in the z direction (vertical direction) and releases the displacement and rotational degrees of freedom in the x (length direction) and y (width direction); the fixed supported end restricts the displacement in the x, y, and z directions and the rotational degrees of freedom about the x and y axes, ensuring that the constraints are consistent with the actual support state.

[0169] By applying boundary constraints and load distribution, the stress state of the gate under different working conditions is simulated, and a stamping model based on the gate material specifications is constructed.

[0170] The process of calculating the theoretical deformation curve of the gate includes:

[0171] Based on the principles of mechanics of materials and combined with the stamping model, the differential equation for the deflection of the gate under water pressure is established, and the formula is expressed as:

[0172]

[0173] In the formula, Let be the elastic modulus in the material parameters, I be the moment of inertia of the gate section, w be the deflection along the length direction x, and q(x) be the distributed load in the load conditions.

[0174] Considering the constraints and load distribution of the gate, the deflection differential equation is solved using the two-moment theory. The constraints include simply supported and fixed supports, and the load distribution includes uniformly distributed loads and concentrated loads.

[0175] Based on the solution results, the maximum deflection and stress distribution of the gate at different water levels are calculated.

[0176] The equations are solved using the two-moment theory. For a uniformly distributed load (such as hydrostatic pressure), the analytical solution is:

[0177]

[0178] In the formula, L is the length, and q represents the uniformly distributed load acting on the gate.

[0179] For concentrated loads (such as local water pressure at the midpoint of a gate), the analytical solution needs to be superimposed with the deflection component caused by the concentrated force to finally obtain the theoretical deflection w(x) corresponding to different positions x.

[0180] The influence of the nonlinear behavior of the gate on its deformation is analyzed. The nonlinear behavior includes the large deformation effect.

[0181] Based on the calculation results at different water levels, theoretical deformation curves of the gate under different operating conditions are generated.

[0182] By comparing the actual compressive strength values ​​with dynamic water pressure distribution data and analyzing the deviation between the actual deformation data and the theoretical deformation curve, a multi-level safety early warning indicator system is established.

[0183] When the detected value exceeds the safety threshold, an alert is triggered, and an assessment report containing the location and extent of the risk is generated.

[0184] In summary, this embodiment provides a method for early warning of water conservancy facility safety. By integrating a hydrodynamic mathematical model with finite element structural analysis, it achieves a dynamic correlation between water flow load and structural response. Through three-dimensional computational mesh generation and Kriging interpolation, it accurately characterizes the distribution characteristics of water pressure on the surface of the water conservancy facility. Combined with stress concentration factors, it identifies high-risk areas, overcoming the limitations of traditional single-point monitoring. For example, the analysis of gate deformation considers not only hydrostatic pressure but also dynamic factors such as hydrodynamic pressure and wave loads. Through solving the deflection differential equation and nonlinear correction, the theoretical deformation curve closely matches the actual working conditions, providing a reliable benchmark for deviation analysis.

[0185] The solution constructs a complete closed-loop early warning system for water conservancy facilities, centered on hydraulic engineering parameters, hydrological data, and structural parameters. By discretizing fluid dynamics equations using the finite volume method, hydrological data is transformed into dynamic loads that can be directly applied to the structural model. The rebound method and laser ranging technology are used to achieve non-destructive testing of concrete strength and gate deformation. Deep fusion of multi-source data enables the early warning model to respond in real time to dynamic factors such as water level changes and material degradation, significantly improving the scientific rigor of risk assessment.

[0186] By automating data collection and batch model calculations, the cycle of traditional manual inspections is significantly shortened, greatly improving the timeliness of early warnings. Simultaneously, differentiated analysis modules are designed for different types of water conservancy facilities; for example, a dynamic reinforcement model is used for gates, and carbonation depth correction is introduced for dams, enabling the solution to adapt to diverse engineering scenarios. Furthermore, a multi-level early warning indicator system combined with nonlinear behavior analysis avoids the limitations of fixed thresholds, allowing for dynamic adjustment of early warning levels based on the actual structural condition. This provides precise guidance for operation and maintenance decisions, significantly reducing accident rates and operation and maintenance costs.

[0187] Based on the same general inventive concept, this invention also protects a water conservancy facility safety early warning system. The water conservancy facility safety early warning system provided by this invention will be described below. The water conservancy facility safety early warning system described below and the water conservancy facility safety early warning method described above can be referred to and correspond to each other.

[0188] Figure 2 This is a schematic diagram of the structure of a water conservancy facility safety early warning system provided in an embodiment of the present invention.

[0189] like Figure 2 As shown, a water conservancy facility safety early warning system includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor. The processor includes a data acquisition module, a water pressure distribution calculation module, a key area screening module, a compressive strength calculation module, a deformation data acquisition module, and a comparison and early warning module.

[0190] The data acquisition module is used to collect parameters of water conservancy projects, hydrological data, and structural parameters of water conservancy facilities. The structural parameters of water conservancy facilities include the grade parameters of concrete dams and the material specifications of gates.

[0191] The water pressure distribution calculation module is used to construct a hydrodynamic mathematical model based on fluid mechanics principles according to water conservancy project parameters and hydrological data, and to perform stress analysis on the structure of water conservancy facilities using the finite element method to obtain dynamic water pressure distribution data.

[0192] The key area screening module is used to screen areas with concentrated impact force based on dynamic water pressure distribution data, draw pressure contour maps to locate high-risk areas, and obtain key areas of concern.

[0193] The compressive strength calculation module is used to perform rebound strength testing on key areas of interest, record concrete surface hardness data, and perform conversions to obtain the actual compressive strength value.

[0194] The deformation data acquisition module is used to construct a stamping model based on the gate material specifications, calculate the theoretical deformation curve of the gate, and acquire actual deformation data through laser ranging.

[0195] The comparison and early warning module is used to compare the actual compressive strength value with the dynamic water pressure distribution data, analyze the deviation between the actual deformation data and the theoretical deformation curve, establish a multi-level safety early warning index system, trigger an early warning when the detected value exceeds the safety threshold, and generate an assessment report that includes the location and degree of risk.

[0196] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0197] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for early warning of safety in water conservancy facilities, characterized in that, include: Collect water conservancy project parameters, hydrological data and water conservancy facility structural parameters, including the grade parameters of concrete dams and the material specifications of gates; Based on the hydraulic engineering parameters and hydrological data, a hydrodynamic mathematical model based on the principles of fluid mechanics was constructed. The finite element method was used to analyze the stress on the hydraulic facility structure and obtain dynamic water pressure distribution data. The process of constructing a hydrodynamic mathematical model based on fluid dynamics principles includes: The area where the water conservancy facilities are located is divided into three-dimensional spaces to form a three-dimensional computational grid, thereby obtaining the boundary range of the water area and the water conservancy facilities; Based on the Navier-Stokes equations and the continuity equation, and combined with the parameters of the hydraulic engineering and the structural parameters of the hydraulic facilities, initial conditions and boundary conditions are set. The initial conditions represent the flow state parameters, and the boundary conditions are the flow parameter restrictions within the boundary range of the water area and the hydraulic facilities. The flow state parameters include flow velocity magnitude, flow velocity direction, flow pressure, and flow density. The flow parameter restrictions include velocity restrictions, pressure restrictions, and flow rate restrictions at the boundary. The Navier-Stokes equations and continuity equations are discretized using the finite volume method, transforming continuous water flow motion into numerical calculations at discrete nodes. Dynamic numerical simulation of continuous water flow motion is then performed to obtain a hydrodynamic mathematical model. Based on the dynamic water pressure distribution data, areas with concentrated impact force are screened, pressure contour maps are drawn to locate high-risk areas, and key areas of concern are identified. The rebound strength test was performed on the key areas of concern, the surface hardness data of the concrete was recorded and converted to obtain the actual compressive strength value. Based on the gate material specifications, a stamping model based on the gate material specifications is constructed, the theoretical deformation curve of the gate is calculated, and the actual deformation data is obtained through laser ranging. The process of constructing a stamping model based on the gate material specifications includes: Determine the geometric parameters and load conditions of the gate, wherein the geometric parameters include length, width, thickness and support method, and the load conditions include hydrostatic pressure, hydrodynamic pressure and wave load; Select a material constitutive model that matches the gate material, and set the gate's material parameters, including elastic modulus, Poisson's ratio, yield strength, and ultimate strength. Define the contact conditions of the gate, including the frictional contact between the gate and the gate slot; By applying boundary constraints and load distribution, the stress state of the gate under different working conditions is simulated, and a stamping model based on the gate material specifications is constructed. By comparing the actual compressive strength value with the dynamic water pressure distribution data, and analyzing the deviation between the actual deformation data and the theoretical deformation curve, a multi-level safety early warning index system is established. When the detected value exceeds the safety threshold, an alert is triggered, and an assessment report containing the location and extent of the risk is generated.

2. The method for early warning of water conservancy facility safety according to claim 1, characterized in that, The hydrological data includes water level, flow velocity, pressure, and temperature; the hydraulic engineering parameters include reservoir capacity and dam geometry, with the dam geometry including height, slope, and top width.

3. The method for early warning of water conservancy facility safety according to claim 1, characterized in that, The process of obtaining dynamic water pressure distribution data includes: A finite element model of the hydraulic facility structure is constructed, the finite element model including the concrete dam body and the gate; The hydraulic load is calculated based on the hydrodynamic mathematical model and applied to the finite element model in the form of nodal forces. The material constitutive relation of the finite element model is defined based on the structural parameters of the water conservancy facility, the stress concentration factor of the water conservancy facility structure is calculated, and a load combination is formed by combining the water pressure load. By combining the load combinations, the stress field and displacement field of the finite element model in the hydrodynamic mathematical model are solved using the time history analysis method to obtain dynamic water pressure distribution data.

4. The method for early warning of water conservancy facility safety according to claim 1, characterized in that, The process of screening areas of concentrated impact includes: Based on the dynamic water pressure distribution data, the dynamic water pressure gradient on the surface of the hydraulic facility structure is calculated, and the area of ​​the hydraulic facility structure surface where the dynamic water pressure gradient exceeds a preset threshold is marked as a potential impact force concentration area.

5. The method for early warning of water conservancy facility safety according to claim 3, characterized in that, The process of identifying key areas of focus includes: The dynamic water pressure distribution data is interpolated onto a regular grid to form a continuous pressure data distribution. The continuous pressure data distribution is processed using the Kriging interpolation algorithm to generate a continuous pressure field; Based on the pressure values ​​at equal intervals, a closed curve is plotted on the continuous pressure field to form a pressure contour map. Identify areas of dense contour lines and high-value areas in the pressure contour map, and mark key areas of interest based on the stress concentration factor.

6. The method for early warning of water conservancy facility safety according to claim 1, characterized in that, The process of obtaining the actual compressive strength value includes: Select a measurement area within the key area of ​​interest, and evenly distribute N measurement points in each measurement area; Use a standard rebound hammer perpendicular to the concrete surface to conduct the test and record the rebound value at each test point; Remove outlier data and calculate the average rebound value of the test area. The outlier data includes outliers in carbonization depth. The carbonation depth of concrete was measured, and the thickness of the carbonation layer was determined using the phenolphthalein reagent colorimetric method. The compressive strength of concrete is obtained by comparing the average rebound value of the test area with the carbonation depth of the concrete and converting the values ​​using the strength test curve.

7. The method for early warning of water conservancy facility safety according to claim 1, characterized in that, The process of calculating the theoretical deformation curve of the gate includes: Based on the principles of mechanics of materials and combined with the aforementioned stamping model, a differential equation for the deflection of the gate under water pressure is established. Considering the constraints and load distribution of the gate, the deflection differential equation is solved using the two-moment theory. The constraints include simply supported and fixed supports, and the load distribution includes uniformly distributed loads and concentrated loads. Based on the solution results, calculate the maximum deflection and stress distribution of the gate at different water levels; The influence of the nonlinear behavior of the gate on its deformation is analyzed, including the large deformation effect. Based on the calculation results at different water levels, theoretical deformation curves of the gate under different operating conditions are generated.

8. A water conservancy facility safety early warning system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements a water conservancy facility safety early warning method as described in any one of claims 1 to 7.

Images