A method and system for safety assessment and early warning of static ice pressure on a tower base of a power transmission tower

Abstract

This invention belongs to the field of power facility safety and cold-region engineering technology, and discloses a method and system for safety assessment and early warning of static ice pressure on transmission tower foundations. The method includes: establishing transient heat conduction control equations and viscoelastic constitutive equations to control ice layer behavior; establishing a three-dimensional finite element model; setting boundary conditions; transforming the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equations, viscoelastic constitutive equations, and boundary conditions, and performing simulation solutions using multiphysics coupling simulation software to obtain corresponding simulation results; extracting displacement and stress field data from the simulation results, identifying deformation modes and stress concentration areas of the tower foundation structure, and assessing the corresponding damage risks; and formulating a static ice pressure monitoring scheme and engineering protection measures for transmission towers. This invention can accurately simulate the interaction between temperature and stress fields, and systematically reveal the long-term cumulative damage mechanism of static ice pressure on transmission tower foundations.

Description

Technical Field

[0001] This invention relates to the fields of power facility safety and cold region engineering technology, and in particular to a method and system for safety assessment and early warning of static ice pressure on transmission tower foundations. Background Technology

[0002] In cold regions such as Northeast and Northwest China, winters are harsh and the ice season is long. Transmission towers, as critical infrastructure of the power grid, are directly related to the reliability of power supply. During the winter freezing period, the soil or surface water around the tower base easily freezes, forming ice. This ice expands in volume due to changes in ambient temperature, and the tower base structure constrains this free expansion, resulting in significant static ice pressure (also known as frost heave force) on the tower base. This static ice pressure exerts uneven lifting or lateral thrust on the tower base. When this force is transmitted to the main tower structure, it can easily cause structural damage such as bending of the main tower members, twisting and breaking of diagonal and auxiliary members. In severe cases, it can even lead to the complete overturning of the transmission tower, causing not only structural damage but also power outages and posing a serious threat to the safe and stable operation of the power grid.

[0003] Currently, research on static ice pressure is largely concentrated in the field of hydraulic engineering, mainly focusing on the ice pressure action mechanism and protection of hydraulic structures such as dams, bridge piers, and reservoir gates. However, transmission tower foundations are typical high-rise structural foundations, with significant differences in structural form and stress characteristics compared to hydraulic structures. The interaction mechanism between the tower foundation and the surrounding ice layer is more complex, representing a highly complex multi-physics coupled problem integrating transient heat conduction, ice thermal expansion, nonlinearity of ice viscoelastic materials, and the deformation response of the tower foundation structure. Existing technologies for ice-resistant design and safety assessment of transmission tower foundations often employ simplified calculation methods based on empirical formulas or traditional analytical analysis methods. However, these methods struggle to accurately characterize the complex mechanical properties of the tower foundation structure, especially failing to effectively simulate the complex mechanical behavior, damage evolution paths, and ultimate failure modes of secondary components such as inclined members and auxiliary materials under continuous static ice pressure during long-term freezing.

[0004] Therefore, how to provide a method and system for safety assessment and early warning of static ice pressure on the foundation of power transmission towers is an urgent problem to be solved. Summary of the Invention

[0005] This invention provides a method and system for safety assessment and early warning of static ice pressure on the foundation of power transmission towers, in order to solve the above-mentioned technical problems existing in the prior art.

[0006] According to a first aspect of the present invention, a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower is provided.

[0007] In one embodiment, a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower includes:

[0008] Based on thermodynamics and solid mechanics theories, transient heat conduction control equations and viscoelastic constitutive equations governing ice layer behavior are established.

[0009] Based on the design drawings of the target power transmission tower base, the geometric dimensions and material parameters of the base structure are obtained, and a three-dimensional finite element model including the ice layer, the lower water body and the base structure is established using multiphysics coupling simulation software.

[0010] Based on the constructed three-dimensional finite element model and combined with the actual working conditions, boundary conditions are set, including thermal boundaries and mechanical boundaries.

[0011] Based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, the multiphysics coupling problem is transformed into an optimization problem, and the simulation is performed by multiphysics coupling simulation software to obtain the corresponding simulation results.

[0012] Extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk;

[0013] Based on the assessment results of damage risks, a static ice pressure monitoring scheme and engineering protection measures were developed for transmission towers.

[0014] In one embodiment, the expression for the transient heat conduction control equation is:

[0015] ;

[0016] In the formula, ρ ice c represents the density of ice. ice λ represents the specific heat capacity of ice; T represents temperature; t represents time; ice This represents the thermal conductivity of ice.

[0017] In one embodiment, the expression for the viscoelastic constitutive equation is:

[0018] ;

[0019] In the formula, ε represents the total strain; ε e ε represents elastic strain; t Indicates thermal strain; ε c Indicates creep strain;

[0020] The expression for the thermal strain is:

[0021] ;

[0022] In the formula, ε t Indicates thermal strain; α ice T represents the coefficient of thermal expansion of ice; T represents temperature; T melt This indicates the melting point temperature of ice;

[0023] The expression for the creep strain is:

[0024] ;

[0025] In the formula, ε c Indicates creep strain; A nor σ represents the temperature-dependent viscosity coefficient; σ represents the actual stress; σ ref Indicates the reference stress; n represents the creep index; t represents time.

[0026] The expression for the viscosity coefficient is:

[0027] ;

[0028] In the formula, A nor Represents the temperature-dependent viscosity coefficient; Q represents the creep activation energy of ice; R represents the gas constant; T represents the temperature; T ref Indicates the reference temperature.

[0029] In one embodiment, the process of transforming the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equation, the viscoelastic constitutive equation, and boundary conditions, and then performing the simulation solution using multiphysics coupling simulation software to obtain the corresponding simulation results includes:

[0030] The established transient heat conduction control equation, viscoelastic constitutive equation and set boundary conditions are converted into residual terms, and the residual terms are fused into the loss function of the preset neural network to construct a physical information neural network, so as to transform the multi-physics coupling problem into an optimization problem.

[0031] The constructed physical information neural network is trained, and the trained physical information neural network is used for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation.

[0032] Starting with the generated initial temperature-stress coupled field, transient thermo-mechanical coupling calculations are performed using multiphysics coupling simulation software to solve the mechanical action process of static ice pressure on the tower base structure and obtain the corresponding simulation results.

[0033] In one embodiment, training the constructed physical information neural network and using the trained physical information neural network for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation includes:

[0034] A two-dimensional cross-sectional model obtained by symmetrically cutting a three-dimensional finite element model is selected, and a preset local spatiotemporal domain is used as the training domain. Spatiotemporal coordinate points are randomly sampled within the training domain as input.

[0035] Using the loss function calculated from the sampling spatiotemporal coordinates as the training driver, the physical information neural network is trained to learn the physical evolution laws of the ice layer temperature field and stress field in the local spatiotemporal domain, thus completing the training of the physical information neural network.

[0036] The spatial coordinates of the three-dimensional finite element model under steady-state conditions are input into the trained physical information neural network. Through the forward propagation of the physical information neural network, the corresponding temperature and stress field distributions are output, and the initial temperature-stress coupling field is generated as the initial condition for transient coupling simulation.

[0037] In one embodiment, the step of using the generated initial temperature-stress coupled field as a starting point, performing transient thermo-mechanical coupled calculations using multiphysics coupling simulation software to solve the mechanical action of static ice pressure on the tower base structure, and obtaining the corresponding simulation results includes:

[0038] The generated initial temperature-stress coupled field is used as the starting point. The simulation time period is set using multiphysics coupling simulation software, and multiple simulation time points are selected as outputs.

[0039] Based on the set simulation time period, the simulation simulates the evolution of the transient temperature field inside the ice layer caused by changes in atmospheric temperature, and solves the mechanical action process of the static ice pressure generated by the coupling of the corresponding temperature field with the thermal expansion and creep of the ice layer on the tower base structure, obtaining the simulation results at each simulation time point.

[0040] In one embodiment, the extraction of displacement and stress field data from the simulation results, the identification of deformation modes and stress concentration areas of the tower base structure based on the displacement and stress field data, and the assessment of the corresponding damage risk include:

[0041] Based on the obtained simulation results, the displacement and stress field data of the three-dimensional finite element model at each simulation time point are extracted, and displacement cloud map and equivalent stress cloud map are generated based on the displacement and stress field data.

[0042] A comparative analysis of multiple simulation time points was performed on the generated displacement cloud map and equivalent stress cloud map to identify and track the spatiotemporal evolution of deformation modes and stress concentration areas of key components in the tower foundation structure.

[0043] Quantitative data is extracted from the simulation results and evaluated against a pre-established damage index system. Based on the evaluation results, the corresponding damage risk is obtained.

[0044] In one embodiment, the key components include: the main tower base material, the diagonal material, and the auxiliary material.

[0045] In one embodiment, the damage risks include: uneven bulging of the tower base structure, bending deformation of the diagonal members, and stress concentration at the component connection nodes.

[0046] According to a second aspect of the present invention, a system for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower is provided.

[0047] In one embodiment, the static ice pressure safety assessment and early warning system for power transmission tower foundations includes:

[0048] The equation-building module is used to establish transient heat conduction control equations and viscoelastic constitutive equations that govern the behavior of ice layers based on thermodynamic and solid mechanics theories.

[0049] The finite element model building module is used to obtain the geometric dimensions and material parameters of the tower base structure based on the design drawings of the target power transmission tower base, and to build a three-dimensional finite element model including the ice layer, the lower water body and the tower base structure using multiphysics coupling simulation software.

[0050] The boundary condition setting module is used to set boundary conditions based on the constructed three-dimensional finite element model and the actual working conditions. The boundary conditions include thermal boundaries and mechanical boundaries.

[0051] The simulation results acquisition module is used to transform the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, and to perform the simulation solution through multiphysics coupling simulation software to obtain the corresponding simulation results.

[0052] The damage risk assessment module is used to extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk.

[0053] The safety early warning and protection module is used to develop static ice pressure monitoring schemes and engineering protection measures for transmission towers based on the assessment results of damage risks.

[0054] According to a third aspect of the present invention, a computer device is provided.

[0055] In some embodiments, the computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method described above.

[0056] According to a fourth aspect of the present invention, a computer-readable storage medium is provided.

[0057] In one embodiment, a computer program is stored on the computer-readable storage medium, which, when executed by a processor, implements the steps of the above method.

[0058] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0059] 1. This invention, through the finite element method based on thermo-coupling, can accurately simulate the interaction between temperature field and stress field, systematically revealing the long-term cumulative damage mechanism of static ice pressure on the foundation of transmission towers, and breaking through the limitations of traditional simplified methods.

[0060] 2. This invention can predict the response of iron tower structures under different ice conditions and temperature histories through numerical simulation before actual ice damage occurs, providing a scientific basis for disaster prevention and mitigation decisions and realizing the transformation from passive response to proactive prevention.

[0061] 3. The simulation analysis results in this invention can be directly transformed into engineering practice guidance, such as identifying key components that need to be strengthened, optimizing the deployment of safety monitoring sensors, and evaluating the effectiveness of different protective measures, which has extremely high engineering application value and economic benefits.

[0062] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0063] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0064] Figure 1 This is a flowchart illustrating a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment.

[0065] Figure 2 This is a schematic diagram illustrating the principle of a static ice pressure safety assessment and early warning system for power transmission tower foundations, according to an exemplary embodiment.

[0066] Figure 3 This is a schematic diagram of the structure of a computer device according to an exemplary embodiment;

[0067] Figure 4 This is a schematic diagram of the finite element model of the interaction between the tower base and the ice layer, illustrating a method for safety assessment and early warning of static ice pressure on the base of a power transmission tower according to an exemplary embodiment.

[0068] Figure 5This is a schematic diagram illustrating the thermal and mechanical boundary conditions for a method of safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment.

[0069] Figure 6 This is a transient simulation of a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment, up to 72 hours, showing the deformation morphology and stress distribution cloud map of the tower foundation.

[0070] Figure 7 This is a transient simulation of a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment, up to 144 hours, showing the deformation morphology and stress distribution cloud map of the tower foundation.

[0071] Figure 8 This is a transient simulation of a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment, up to 216 hours, showing the deformation morphology and stress distribution cloud map of the tower foundation.

[0072] Figure 9 This is a transient simulation of a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, according to an exemplary embodiment, up to 288 hours, showing the deformation morphology and stress distribution cloud map of the tower foundation. Detailed Implementation

[0073] The following description and accompanying drawings fully illustrate specific embodiments described herein to enable those skilled in the art to practice them. Some portions and features of certain embodiments may be included in or replace portions and features of other embodiments. The scope of the embodiments herein includes the entire scope of the claims and all available equivalents thereof. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0074] The modules in the apparatus or system of this application can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0075] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0076] Figure 1 An embodiment of the present invention is shown, which provides a method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower.

[0077] In this optional embodiment, the method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower includes:

[0078] Step S101: Based on thermodynamics and solid mechanics theory, establish the transient heat conduction control equation and viscoelastic constitutive equation that control the behavior of the ice layer;

[0079] Step S102: Based on the design drawings of the target power transmission tower base, obtain the geometric dimensions and material parameters of the base structure, and use multiphysics coupling simulation software to establish a three-dimensional finite element model including the ice layer, the lower water body and the base structure.

[0080] Step S103: Based on the constructed three-dimensional finite element model and combined with the actual working conditions, set boundary conditions, wherein the boundary conditions include thermal boundaries and mechanical boundaries.

[0081] Step S104: Based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, the multiphysics coupling problem is transformed into an optimization problem, and the simulation is performed using multiphysics coupling simulation software to obtain the corresponding simulation results.

[0082] Step S105: Extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk.

[0083] Step S106: Based on the assessment results of damage risk, formulate a static ice pressure monitoring plan and engineering protection measures for transmission towers.

[0084] In this optional embodiment, the expression for the transient heat conduction control equation is:

[0085] ;

[0086] In the formula, ρ ice c represents the density of ice. ice λ represents the specific heat capacity of ice; T represents temperature; t represents time; ice This represents the thermal conductivity of ice.

[0087] In this optional embodiment, the expression for the viscoelastic constitutive equation is:

[0088] ;

[0089] In the formula, ε represents the total strain; ε e ε represents elastic strain; t Indicates thermal strain; ε c Indicates creep strain;

[0090] The expression for the thermal strain is:

[0091] ;

[0092] In the formula, ε t Indicates thermal strain; α ice T represents the coefficient of thermal expansion of ice; T represents temperature; T melt This indicates the melting point temperature of ice;

[0093] The expression for the creep strain is:

[0094] ;

[0095] In the formula, ε c Indicates creep strain; A nor σ represents the temperature-dependent viscosity coefficient; σ represents the actual stress; σ ref Indicates the reference stress; n represents the creep index; t represents time.

[0096] The expression for the viscosity coefficient is:

[0097] ;

[0098] In the formula, A nor Represents the temperature-dependent viscosity coefficient; Q represents the creep activation energy of ice; R represents the gas constant; T represents the temperature; T ref Indicates the reference temperature.

[0099] In this optional embodiment, the process of transforming the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equation, the viscoelastic constitutive equation, and boundary conditions, and then performing the simulation solution using multiphysics coupling simulation software to obtain the corresponding simulation results includes:

[0100] The established transient heat conduction control equation, viscoelastic constitutive equation and set boundary conditions are converted into residual terms, and the residual terms are fused into the loss function of the preset neural network to construct a physical information neural network, so as to transform the multi-physics coupling problem into an optimization problem.

[0101] The constructed physical information neural network is trained, and the trained physical information neural network is used for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation.

[0102] Starting with the generated initial temperature-stress coupled field, transient thermo-mechanical coupling calculations are performed using multiphysics coupling simulation software to solve the mechanical action process of static ice pressure on the tower base structure and obtain the corresponding simulation results.

[0103] In this optional embodiment, training the constructed physical information neural network and using the trained physical information neural network for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation includes:

[0104] A two-dimensional cross-sectional model obtained by symmetrically cutting a three-dimensional finite element model is selected, and a preset local spatiotemporal domain is used as the training domain. Spatiotemporal coordinate points are randomly sampled within the training domain as input.

[0105] Using the loss function calculated from the sampling spatiotemporal coordinates as the training driver, the physical information neural network is trained to learn the physical evolution laws of the ice layer temperature field and stress field in the local spatiotemporal domain, thus completing the training of the physical information neural network.

[0106] The spatial coordinates of the three-dimensional finite element model under steady-state conditions are input into the trained physical information neural network. Through the forward propagation of the physical information neural network, the corresponding temperature and stress field distributions are output, and the initial temperature-stress coupling field is generated as the initial condition for transient coupling simulation.

[0107] In this optional embodiment, the step of using the generated initial temperature-stress coupled field as a starting point to perform transient thermo-mechanical coupled calculations using multiphysics coupling simulation software to solve the mechanical action process of static ice pressure on the tower base structure and obtain the corresponding simulation results includes:

[0108] The generated initial temperature-stress coupled field is used as the starting point. The simulation time period is set using multiphysics coupling simulation software, and multiple simulation time points are selected as outputs.

[0109] Based on the set simulation time period, the simulation simulates the evolution of the transient temperature field inside the ice layer caused by changes in atmospheric temperature, and solves the mechanical action process of the static ice pressure generated by the coupling of the corresponding temperature field with the thermal expansion and creep of the ice layer on the tower base structure, obtaining the simulation results at each simulation time point.

[0110] In this optional embodiment, the extraction of displacement and stress field data from the simulation results, the identification of deformation modes and stress concentration areas of the tower base structure based on the displacement and stress field data, and the assessment of the corresponding damage risks include:

[0111] Based on the obtained simulation results, the displacement and stress field data of the three-dimensional finite element model at each simulation time point are extracted, and displacement cloud map and equivalent stress cloud map are generated based on the displacement and stress field data.

[0112] A comparative analysis of multiple simulation time points was performed on the generated displacement cloud map and equivalent stress cloud map to identify and track the spatiotemporal evolution of deformation modes and stress concentration areas of key components in the tower foundation structure.

[0113] Quantitative data is extracted from the simulation results and evaluated against a pre-established damage index system. Based on the evaluation results, the corresponding damage risk is obtained.

[0114] In this optional embodiment, the key components include: the main tower base material, the inclined material, and the auxiliary material.

[0115] In this alternative embodiment, the damage risks include: uneven bulging of the tower base structure, bending deformation of the diagonal members, and stress concentration at the component connection nodes.

[0116] Figure 2 An embodiment of the static ice pressure safety assessment and early warning system for power transmission tower foundations according to the present invention is shown.

[0117] In this optional embodiment, the static ice pressure safety assessment and early warning system for power transmission tower foundations includes:

[0118] Equation establishment module 201 is used to establish transient heat conduction control equations and viscoelastic constitutive equations that control the behavior of ice layers based on thermodynamic and solid mechanics theories.

[0119] The finite element model building module 202 is used to obtain the geometric dimensions and material parameters of the tower base structure based on the design drawings of the target power transmission tower base, and to build a three-dimensional finite element model including the ice layer, the lower water body and the tower base structure using multiphysics coupling simulation software.

[0120] The boundary condition setting module 203 is used to set boundary conditions based on the constructed three-dimensional finite element model and the actual working conditions, wherein the boundary conditions include thermal boundaries and mechanical boundaries.

[0121] The simulation results acquisition module 204 is used to transform the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, and to perform the simulation solution through multiphysics coupling simulation software to obtain the corresponding simulation results.

[0122] The damage risk assessment module 205 is used to extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk.

[0123] The safety early warning and protection module 206 is used to develop static ice pressure monitoring schemes and engineering protection measures for transmission towers based on the assessment results of damage risks.

[0124] To facilitate understanding of the above technical solutions of the present invention, the following further describes the above technical solutions of the present invention from the perspectives of architecture and principle, as follows:

[0125] S1. Theoretical Model Construction: Based on thermodynamics and solid mechanics theories, physical equations controlling the behavior of ice layers are established. In terms of temperature field, transient heat conduction equations are used to describe the temperature distribution inside the ice layer that changes with time and space. In terms of stress field, a viscoelastic constitutive equation that can simultaneously consider the instantaneous elastic response of ice, thermal expansion caused by temperature changes, and time-related creep characteristics is adopted to accurately describe the mechanical behavior of ice under load.

[0126] S2. Finite Element Modeling: Based on the actual design drawings of the target transmission tower (taking a 220kV tower as an example), obtain its precise geometric dimensions (such as the cross-sectional specifications of the main and diagonal members) and material parameters (the main member is usually Q345 steel, and the auxiliary member is Q235 steel); using multiphysics coupling simulation software such as COMSOL Multiphysics, establish a refined three-dimensional finite element model that includes the ice layer, the underlying water body, and the tower base structure itself, such as... Figure 4 As shown.

[0127] The horizontal dimensions of the three-dimensional finite element model are set to 5m×5m, the thickness is 0.5m, and the height of the underlying water layer is set to 1m.

[0128] S3. Boundary Condition Setting: Reasonable boundary conditions are set for the 3D finite element model to reflect the real physical environment; Thermal Boundary: A time-varying atmospheric temperature curve determined based on local meteorological data is applied to the upper surface of the ice layer; the lower surface is in contact with water and is kept constant at the melting point of ice (273.15K); the sides are simplified as adiabatic boundaries (zero heat flux) because they are far from the main interaction zone; Mechanical Boundary: The bottom of the tower base is embedded in the foundation and is set as a fixed constraint; the top bears the load transmitted by the upper tower body and is simplified as an equivalent concentrated force or pressure; the far-end boundary of the ice layer constrains its normal displacement, such as... Figure 5 As shown.

[0129] S4. Coupled Simulation Solution: Based on the relationship between the transient heat conduction equation and the viscoelastic constitutive equation, and combined with thermal and mechanical boundary conditions, the governing equation, constitutive equation, and boundary conditions are integrated into the loss function of the pre-defined neural network in the form of residual terms, constructing a physical information neural network. This transforms the multi-physics coupling problem into an optimization problem. During the training phase, a simplified two-dimensional cross-sectional model representing the key characteristics of the ice layer (obtained by symmetrical cutting of the three-dimensional tower base-ice layer model) and a local hourly spatial domain (a finite region of the ice layer near the tower base in the initial few hours) are selected as the training domain. Randomly sampled spatiotemporal coordinate points within this domain are used as input, and the calculated loss function drives the network training, enabling the network to learn the basic physical evolution laws of the ice layer temperature field and stress field within the local spatiotemporal range. After training, the network is used for inference. The spatial coordinates of the actual 3D model under steady-state conditions (constant boundary conditions) are input into the trained network. The network forward propagation directly outputs the corresponding temperature and stress field distributions, thereby generating a globally physical consistent and smooth initial temperature-stress coupling field, which serves as the initial condition for subsequent transient coupling simulations. After initialization, the transient thermo-mechanical coupling analysis is initiated starting from this steady-state temperature field. In COMSOL software, by setting a simulation time of up to 12 days (288 hours) and selecting multiple key time points such as 3 days (72h), 6 days (144h), 9 days (216h), and 12 days (288h) as outputs, the system solves the evolution of the transient temperature field inside the ice layer caused by the change in the top atmospheric temperature during this period, as well as the mechanical action of the static ice pressure generated by the coupling of this temperature field with the thermal expansion and creep behavior of the ice layer on the tower base structure.

[0130] The total duration of the transient thermo-mechanical coupling calculation is no less than 9 days to ensure that the creep relaxation effect of the ice layer and the stable trend of the tower base deformation can be simulated.

[0131] S5. Damage Mechanism Analysis: After completing the transient thermo-mechanical coupling calculation, the displacement and stress field data of the entire tower base-ice layer model at different time nodes (such as the 3rd, 6th, 9th, and 12th days of the simulation) are extracted, and displacement cloud maps and von Mises equivalent stress cloud maps are generated and compared. The focus is on key parts such as the contact area between the tower base and the ice layer and the connection of the inclined materials. From the displacement cloud maps, the location, range, and development process of the local upward bulge caused by the expansion and pressure of the tower base under the ice layer are visually identified and tracked. The quantitative results obtained from the above simulation (such as the maximum equivalent stress value of key monitoring points) are compared with the damage index system established in this field in advance. For example, the stress level is divided into: below the yield strength is safe, reaching the yield strength is a warning, and exceeding the yield strength is dangerous, thereby providing clear judgment criteria based on simulation data for early warning.

[0132] S6. Safety Early Warning and Protection: Based on the early warning locations identified in step S5, propose targeted engineering measures: For example, install static ice pressure sensors at these locations and establish a real-time monitoring and alarm system based on simulated early warning thresholds; during the winter freezing period, actively break up the ice layer around the tower base and fill the ice-breaking area with low thermal conductivity materials such as slag and sawdust to form an isolation layer to block the path of ice and water refreezing, thereby mitigating the harm of static ice pressure from the root.

[0133] Furthermore, the application is illustrated using a typical iron tower of a 220kV transmission line in a certain region as an example. First, the structural design drawings of the tower base are collected, clarifying the specifications and dimensions (such as angle steel type) and material properties (elastic modulus, Poisson's ratio, etc.) of the main materials, diagonal members, and auxiliary materials. Then, in COMSOL Multiphysics software, based on… Figure 4 Based on the structural relationships shown, a refined finite element model is established; the dimensions of the ice layer region are set to 5m×5m×0.5m (length×width×thickness), and the height of the underlying water layer is set to 1m.

[0134] Based on historical meteorological data for a certain region, a time-varying atmospheric temperature curve for the upper boundary of the ice layer was constructed. The constitutive model of the ice body adopted the viscoelastic model described in this invention, and the relevant parameter values ​​are as follows: creep activation energy Q = 67 kJ / mol, reference temperature T. ref =263.15K, creep index n=3, etc.; according to Figure 5 The scheme shown sets all thermal and mechanical boundary conditions.

[0135] After setup, steady-state thermal analysis was first performed to obtain a stable initial temperature field; subsequently, transient thermo-mechanical coupling calculations were conducted over a period of 12 days based on this. The simulation results clearly demonstrate the damage development process: such as... Figure 6 and Figure 7 As shown, after 144 hours (6 days), the tower base exhibited significant uneven bulging under ice pressure; the diagonal members and auxiliary materials, due to their relatively small cross-sectional dimensions and large slenderness ratio, showed significant bending deformation earlier (approximately 144 hours) under the overall compression effect caused by the expansion of the ice layer, such as... Figure 7 As shown; however, the main members with larger cross-sectional stiffness exhibit relatively small bending deformation, which only becomes more noticeable after 216 hours (9 days), and the deformation of the entire tower base structure gradually stabilizes after approximately 9 days, as... Figure 8 and Figure 9 As shown, this fully demonstrates the stress relaxation effect caused by ice creep; this simulation process successfully reproduced the tower base failure modes observed in the field investigation (such as uneven tower base bulging, bending of diagonal members, etc.), verifying the effectiveness and accuracy of this method.

[0136] Based on the simulation analysis results, targeted suggestions can be made to power grid operation and maintenance units: For towers located in areas prone to water accumulation and freezing, the inspection and monitoring of the condition of the tower base inclined members and auxiliary materials should be strengthened; before the arrival of winter, the water accumulated around the tower base can be drained or drained, or a certain thickness of inexpensive insulation materials such as slag and perlite can be laid around the tower base as an isolation layer to effectively suppress or reduce the generation of static ice pressure and ensure the safe operation of transmission lines.

[0137] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 3 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database stores static and dynamic information data. The network interface communicates with external terminals via a network connection. When the computer program is executed by the processor, it implements the steps in the above method embodiments.

[0138] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the computer device to which the present invention is applied. A specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0139] In addition, the present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0140] In addition, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0141] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0142] This invention is not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this invention is limited only by the appended claims.

Claims

1. A method for safety assessment and early warning of static ice pressure on the foundation of a power transmission tower, characterized in that, The method includes: Based on thermodynamics and solid mechanics theories, transient heat conduction control equations and viscoelastic constitutive equations governing ice layer behavior are established. Based on the design drawings of the target power transmission tower base, the geometric dimensions and material parameters of the base structure are obtained, and a three-dimensional finite element model including the ice layer, the lower water body and the base structure is established using multiphysics coupling simulation software. Based on the constructed three-dimensional finite element model and combined with the actual working conditions, boundary conditions are set, including thermal boundaries and mechanical boundaries. Based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, the multiphysics coupling problem is transformed into an optimization problem, and the simulation is performed by multiphysics coupling simulation software to obtain the corresponding simulation results. Extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk; Based on the assessment results of damage risks, a static ice pressure monitoring scheme and engineering protection measures were developed for transmission towers.

2. The method for safety assessment and early warning of static ice pressure on transmission tower foundations according to claim 1, characterized in that, The expression for the transient heat conduction control equation is: ； In the formula, ρ ice c represents the density of ice. ice λ represents the specific heat capacity of ice; T represents temperature; t represents time; ice This represents the thermal conductivity of ice.

3. The method for safety assessment and early warning of static ice pressure on transmission tower foundations according to claim 2, characterized in that, The expression for the viscoelastic constitutive equation is: ； In the formula, ε represents the total strain; ε e ε represents elastic strain; t Indicates thermal strain; ε c Indicates creep strain; The expression for the thermal strain is: ； In the formula, ε t Indicates thermal strain; α ice T represents the coefficient of thermal expansion of ice; T represents temperature; T melt This indicates the melting point temperature of ice; The expression for the creep strain is: ； In the formula, ε c Indicates creep strain; A nor The viscosity coefficient is temperature-dependent; σ represents the actual stress. σ ref Indicates the reference stress; n represents the creep index; t represents time. The expression for the viscosity coefficient is: ； In the formula, A nor Represents the temperature-dependent viscosity coefficient; Q represents the creep activation energy of ice; R represents the gas constant; T represents the temperature; T ref Indicates the reference temperature.

4. The method for safety assessment and early warning of static ice pressure on the foundation of transmission towers according to claim 1, characterized in that, The multiphysics coupling problem is transformed into an optimization problem based on the transient heat conduction control equation, viscoelastic constitutive equation, and boundary conditions. The simulation is then performed using multiphysics coupling simulation software to obtain the following simulation results: The established transient heat conduction control equation, viscoelastic constitutive equation and set boundary conditions are converted into residual terms, and the residual terms are fused into the loss function of the preset neural network to construct a physical information neural network, so as to transform the multi-physics coupling problem into an optimization problem. The constructed physical information neural network is trained, and the trained physical information neural network is used for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation. Starting with the generated initial temperature-stress coupled field, transient thermo-mechanical coupling calculations are performed using multiphysics coupling simulation software to solve the mechanical action process of static ice pressure on the tower base structure and obtain the corresponding simulation results.

5. The method for safety assessment and early warning of static ice pressure on transmission tower foundations according to claim 4, characterized in that, The process of training the constructed physical information neural network and using the trained physical information neural network for inference to generate an initial temperature-stress coupling field as the initial condition for transient coupling simulation includes: A two-dimensional cross-sectional model obtained by symmetrically cutting a three-dimensional finite element model is selected, and a preset local spatiotemporal domain is used as the training domain. Spatiotemporal coordinate points are randomly sampled within the training domain as input. Using the loss function calculated from the sampling spatiotemporal coordinates as the training driver, the physical information neural network is trained to learn the physical evolution laws of the ice layer temperature field and stress field in the local spatiotemporal domain, thus completing the training of the physical information neural network. The spatial coordinates of the three-dimensional finite element model under steady-state conditions are input into the trained physical information neural network. Through the forward propagation of the physical information neural network, the corresponding temperature and stress field distributions are output, and the initial temperature-stress coupling field is generated as the initial condition for transient coupling simulation.

6. The method for safety assessment and early warning of static ice pressure on transmission tower foundations according to claim 5, characterized in that, Starting from the generated initial temperature-stress coupled field, transient thermo-mechanical coupled calculations are performed using multiphysics coupling simulation software to solve the mechanical action of static ice pressure on the tower base structure, and the corresponding simulation results are obtained, including: The generated initial temperature-stress coupled field is used as the starting point. The simulation time period is set using multiphysics coupling simulation software, and multiple simulation time points are selected as outputs. Based on the set simulation time period, the simulation simulates the evolution of the transient temperature field inside the ice layer caused by changes in atmospheric temperature, and solves the mechanical action process of the static ice pressure generated by the coupling of the corresponding temperature field with the thermal expansion and creep of the ice layer on the tower base structure, obtaining the simulation results at each simulation time point.

7. The method for safety assessment and early warning of static ice pressure on transmission tower foundations according to claim 1, characterized in that, The extraction of displacement and stress field data from the simulation results, the identification of deformation modes and stress concentration areas of the tower base structure based on the displacement and stress field data, and the assessment of corresponding damage risks include: Based on the obtained simulation results, the displacement and stress field data of the three-dimensional finite element model at each simulation time point are extracted, and displacement cloud map and equivalent stress cloud map are generated based on the displacement and stress field data. A comparative analysis of multiple simulation time points was performed on the generated displacement cloud map and equivalent stress cloud map to identify and track the spatiotemporal evolution of deformation modes and stress concentration areas of key components in the tower foundation structure. Quantitative data is extracted from the simulation results and evaluated against a pre-established damage index system. Based on the evaluation results, the corresponding damage risk is obtained.

8. The method for safety assessment and early warning of static ice pressure on the foundation of transmission towers according to claim 7, characterized in that, The key components include: the main tower base material, the diagonal members, and the auxiliary materials.

9. The method for safety assessment and early warning of static ice pressure on the foundation of transmission towers according to claim 8, characterized in that, The damage risks include: uneven bulging of the tower base structure, bending deformation of the diagonal members, and stress concentration at the connection nodes of the components.

10. A safety assessment and early warning system for static ice pressure on the foundation of a power transmission tower, characterized in that, The system includes: The equation-building module is used to establish transient heat conduction control equations and viscoelastic constitutive equations that govern the behavior of ice layers based on thermodynamic and solid mechanics theories. The finite element model building module is used to obtain the geometric dimensions and material parameters of the tower base structure based on the design drawings of the target power transmission tower base, and to build a three-dimensional finite element model including the ice layer, the lower water body and the tower base structure using multiphysics coupling simulation software. The boundary condition setting module is used to set boundary conditions based on the constructed three-dimensional finite element model and the actual working conditions. The boundary conditions include thermal boundaries and mechanical boundaries. The simulation results acquisition module is used to transform the multiphysics coupling problem into an optimization problem based on the transient heat conduction control equation, viscoelastic constitutive equation and boundary conditions, and to perform the simulation solution through multiphysics coupling simulation software to obtain the corresponding simulation results. The damage risk assessment module is used to extract displacement and stress field data from the simulation results, identify the deformation mode and stress concentration area of ​​the tower base structure based on the displacement and stress field data, and assess the corresponding damage risk. The safety early warning and protection module is used to develop static ice pressure monitoring schemes and engineering protection measures for transmission towers based on the assessment results of damage risks.

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