Railway bridge damage and driving performance mapping method, device and storage medium

Abstract

The present invention relates to a method, device, and storage medium for mapping railway bridge damage and driving performance, which are applied to the field of traffic safety technology. The method comprises: establishing a mapping relationship between earthquake-induced damage to key components of a track-bridge and track irregularities, comprehensively considering the impact of earthquake-induced damage to the track-bridge system on driving safety performance; using a deep learning method to train a deep learning model using earthquake-induced damage values ​​of components of the track-bridge system and the results of train-track-bridge coupled dynamic responses, and then establishing a quantitative mapping relationship between structural earthquake-induced damage to the track-bridge system and driving performance, thereby quickly and accurately providing safety and stability indicators for driving on the bridge after earthquake damage to key components or parts of the railway bridge track.

Description

Technical Field

[0001] The present invention relates to the field of traffic safety technology, and in particular to a method, device and storage medium for mapping railway bridge damage and driving performance. Background Art

[0002] As a major national strategic and pioneering infrastructure, railways have an irreplaceable position in my country's economic and social development. According to statistics, as of the end of 2021, the national high-speed rail operating mileage has reached 40,000 kilometers, and bridge structures account for more than 50% of most high-speed rail lines. With the continued rapid development of railways, it is inevitable to pass through special areas such as earthquake zones and poor geological conditions. Some railways even pass through multiple Holocene active fault zones such as Longmen Mountain and Yala River. This makes it impossible for high-density trains to avoid driving on bridges during and after earthquakes in time and space, which ultimately leads to serious earthquake threats to bridges and their driving performance in high-intensity areas.

[0003] Current research on bridge traffic performance primarily considers the impact of conventional factors such as bridge pier settlement and temperature loads, while research on seismic effects is relatively scarce. However, seismic effects are highly random and time-varying, and their impact mechanisms and patterns on bridge traffic performance differ significantly from those of the aforementioned factors. Post-seismic damage to the track-bridge system and components can be reflected on the track surface through interlayer interactions between structural components, leading to deterioration of track smoothness, threatening driving safety, and even causing serious consequences such as train derailment. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a method, device and storage medium for mapping railway bridge damage and driving performance, so as to solve the problem in the prior art that there is a lack of research on the impact of earthquake-induced component damage in the track-bridge system on driving safety performance, and the mapping relationship between the two has not yet been established.

[0005] According to a first aspect of an embodiment of the present invention, a method for mapping railway bridge damage and driving performance is provided, the method comprising:

[0006] Using multi-rigid body dynamics theory to establish train models of different train models, and using finite element theory to establish track models and bridge models respectively; using the train models, track models, and bridge models to establish a train-track-bridge coupling system calculation model;

[0007] Obtain earthquake-induced damage values ​​of components in the track-bridge system;

[0008] The basic assumptions of the track-bridge structure theoretical model are set, and the equilibrium differential equations of the bridge and track structure mechanical models are established based on the mechanical properties of the track-bridge structure. Based on the equilibrium differential equations, the mapping relationship between seismic damage to key track-bridge components and track irregularities is obtained;

[0009] obtaining an initial track irregularity sample and an additional track irregularity sample respectively, and superimposing the initial track irregularity sample and the additional track irregularity sample to obtain a vibration-induced random track irregularity sample;

[0010] Inputting the earthquake-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupling system calculation model respectively, and obtaining two sets of train-track-bridge coupling dynamic response results respectively;

[0011] The earthquake-induced damage value of the track-bridge system components is used as a first parameter; the train-track-bridge coupled dynamic response result is obtained by subtracting the two sets of train-track-bridge coupled dynamic response results, and the train-track-bridge coupled dynamic response result is used as a second parameter;

[0012] The pre-built model architecture is trained using the first and second parameters to establish a quantitative mapping relationship between structural earthquake-induced damage and driving performance of the track-bridge system.

[0013] Preferably,

[0014] The method of establishing train models of different train types using multi-rigid body dynamics theory and establishing track models and bridge models using finite element theory includes:

[0015] The train model is obtained by using a rigid body to simulate the train body, front and rear bogies and four wheel sets, and using a spring-damper to simulate the primary and secondary suspension systems of the train.

[0016] The track model is obtained by using spatial beam elements or plate elements to simulate the base plate and track plate of the track, using spatial beam elements to simulate the rails of the track, and using spring-damper elements to simulate the inter-layer connection components of the track.

[0017] The spatial beam unit is used to simulate the foundation, abutment, piers and main beam of the bridge, and the spring-damper is used to simulate the support of the bridge to obtain the bridge model.

[0018] Preferably,

[0019] The establishing of a train-track-bridge coupling system calculation model by using the train model, track model, and bridge model includes:

[0020] The train model, track model and bridge model are used to obtain the wheel-rail interaction between the train and the track, and between the track and the bridge, as well as the bridge-rail interaction; based on the wheel-rail interaction between the train and the track, and between the track and the bridge, a train-track-bridge coupling system calculation model is established;

[0021] The wheel-rail interaction includes: normal action and tangential action between the wheelset and the rail;

[0022] The normal action is obtained by using nonlinear Hertz contact theory, and the tangential action is obtained by using Kaller theory;

[0023] The bridge rails interact with each other to connect the main beam and the base plate.

[0024] Preferably,

[0025] The obtaining of earthquake-induced damage values ​​of components of the track-bridge system includes:

[0026] Generating random seismic waves that take site characteristics into account by using an artificially synthesized seismic wave method or a natural seismic wave amplitude modulation method, inputting the random seismic waves into the train-track-bridge coupled system calculation model to obtain seismic-induced damage values ​​for components of the track-bridge system;

[0027] or,

[0028] The earthquake-induced damage data of the track-bridge system after the historical earthquake is obtained and used as the earthquake-induced damage value of the components of the track-bridge system.

[0029] Preferably,

[0030] The method of establishing a balanced differential equation of the mechanical model of the bridge and track structure based on the mechanical characteristics of the track-bridge structure and obtaining a mapping relationship between earthquake-induced damage to key track-bridge components and track irregularity based on the balanced differential equation includes:

[0031] Establishing deformation expressions of the rails, track plates, and base plates according to the track structure mechanics model, and obtaining matrix expressions of rail deformation, track plate deformation, and base plate deformation according to the deformation expressions of the rails, track plates, and base plates;

[0032] Establishing a deformation expression of the bridge girder according to the bridge structure mechanics model;

[0033] Obtaining spring force expressions for components between different layers of the track structure under horizontal deformation, substituting the matrix expressions for rail deformation, track plate deformation, base plate deformation, and bridge girder deformation into the spring force expressions for components between different layers of the track structure under horizontal deformation, and solving to obtain a fastener spring force matrix under horizontal action;

[0034] The fastener spring force matrix under horizontal action is substituted into the matrix expression of the rail deformation to obtain the mapping relationship between the earthquake-induced damage to the key components of the track-bridge and the track irregularity.

[0035] Preferably,

[0036] The obtaining of the initial track irregularity sample and the additional track irregularity sample comprises:

[0037] Acquiring an initial track irregularity power spectrum, and generating the initial track irregularity samples by a numerical method based on the initial track irregularity power spectrum;

[0038] The earthquake-induced damage values ​​of the components of the track-bridge system are input into the mapping relationship between the earthquake-induced damage of the key components of the track-bridge and the track irregularity to obtain additional track irregularity samples.

[0039] Preferably,

[0040] The training of the pre-built model framework using the first parameter and the second parameter to establish a quantitative mapping relationship between the structural earthquake-induced damage and the driving performance of the track-bridge system includes:

[0041] Preprocessing the first parameter and the second parameter, and selecting a deep learning model based on the characteristics and type of the data;

[0042] constructing a data set using the first and second parameters, and training a selected deep learning model using the constructed data set, and using the trained model as a quantitative mapping relationship model between structural earthquake-induced damage and driving performance of the track-bridge system;

[0043] Inputting the earthquake-induced damage values ​​of the components of the track-bridge system to be tested into a quantitative mapping relationship model between the structural earthquake-induced damage and the driving performance of the track-bridge system, and outputting the train-track-bridge coupled dynamic response results of the track-bridge system;

[0044] Driving safety and stability indicators are selected, and the seismic damage threshold of the track-bridge structure is determined based on the obtained train-track-bridge coupled dynamic response results of the track-bridge system and the driving performance indicator limits specified in the specifications.

[0045] According to a second aspect of an embodiment of the present invention, a device for mapping railway bridge damage and vehicle performance is provided, the device comprising:

[0046] Railway-bridge coupling calculation module: used to establish train models of different train types using multi-rigid body dynamics theory, and to establish track models and bridge models using finite element theory; and to establish a train-track-bridge coupling system calculation model based on the train models, track models, and bridge models;

[0047] Component earthquake damage value acquisition module: used to obtain the component earthquake damage value of the track-bridge system;

[0048] Track irregularity mapping module: This module is used to set the basic assumptions of the track-bridge structure theoretical model and establish the equilibrium differential equations of the bridge and track structure mechanical models based on the mechanical properties of the track-bridge structure. Based on these equilibrium differential equations, the mapping relationship between seismic damage to key track-bridge components and track irregularity is obtained.

[0049] An irregularity sample acquisition module is used to respectively acquire an initial track irregularity sample and an additional track irregularity sample, and superimpose the initial track irregularity sample and the additional track irregularity sample to obtain a vibration-induced random track irregularity sample;

[0050] Coupled dynamic response module: used to input the vibration-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupled system calculation model, respectively, to obtain two sets of train-track-bridge coupled dynamic response results;

[0051] A training parameter acquisition module is configured to use the earthquake-induced damage value of the track-bridge system components as a first parameter; subtract the two sets of train-track-bridge coupled dynamic response results to obtain a train-track-bridge coupled dynamic response result, and use the train-track-bridge coupled dynamic response result as a second parameter;

[0052] Mapping relationship acquisition module: used to train the pre-built model architecture through the first parameter and the second parameter, and then establish a quantitative mapping relationship between the structural earthquake-induced damage and driving performance of the track-bridge system.

[0053] According to a third aspect of an embodiment of the present invention, a storage medium is provided, wherein the storage medium stores a computer program, and when the computer program is executed by a host controller, each step in the above method is implemented.

[0054] The technical solutions provided by the embodiments of the present invention may have the following beneficial effects:

[0055] This application comprehensively considers the impact of seismic damage to the track-bridge system on driving safety performance by establishing a mapping relationship between seismic damage to key components of the track-bridge and track irregularities. A deep learning method is used to train a deep learning model using the seismic damage values ​​of the components of the track-bridge system and the train-track-bridge coupled dynamic response results, thereby establishing a quantitative mapping relationship between the structural seismic damage to the track-bridge system and driving performance. This allows for rapid and accurate provision of safety and stability indicators for driving on railway bridges after earthquake damage to key components or parts of the track.

[0056] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0058] Figure 1 This is a flow chart showing a method for mapping railway bridge damage and driving performance according to an exemplary embodiment;

[0059] Figure 2 is a schematic diagram of a train model according to another exemplary embodiment;

[0060] Figure 3 is a front schematic diagram of a track-bridge calculation model according to another exemplary embodiment;

[0061] Figure 4 is a side schematic diagram of a track-bridge calculation model according to another exemplary embodiment;

[0062] Figure 5 is a seismic response spectrum diagram shown according to another exemplary embodiment;

[0063] Figure 6 is a flowchart illustrating a mapping relationship calculation between earthquake-induced damage to key track-bridge components and track irregularity according to another exemplary embodiment;

[0064] Figure 7 is a schematic diagram showing a sample of vibration-induced rail irregularity according to another exemplary embodiment;

[0065] Figure 8 is a schematic diagram of a deep learning analysis process according to another exemplary embodiment;

[0066] Figure 9 is a system schematic diagram of a railway bridge damage and driving performance mapping device according to another exemplary embodiment;

[0067] In the attached figure: 1- railway bridge coupling calculation module, 2- component seismic damage numerical acquisition module, 3- track irregularity mapping module, 4- irregularity sample acquisition module, 5- coupled dynamic response module, 6- training parameter acquisition module, 7- mapping relationship acquisition module. DETAILED DESCRIPTION

[0068] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0069] Example 1

[0070] Figure 1 FIG. 1 is a flow chart showing a method for mapping railway bridge damage and driving performance according to an exemplary embodiment. Figure 1 As shown, the method includes:

[0071] S1, using multi-rigid body dynamics theory to establish train models of different train models, and using finite element theory to establish track models and bridge models respectively; and establishing a train-track-bridge coupling system calculation model based on the train models, track models, and bridge models;

[0072] S2, obtain the earthquake-induced damage values ​​of components of the track-bridge system;

[0073] S3. Set the basic assumptions of the track-bridge structure theoretical model and establish the equilibrium differential equations of the bridge and track structure mechanical models based on the mechanical properties of the track-bridge structure. Based on the equilibrium differential equations, obtain the mapping relationship between the seismic damage to the key track-bridge components and the track irregularity.

[0074] S4, respectively obtaining an initial track irregularity sample and an additional track irregularity sample, and superimposing the initial track irregularity sample and the additional track irregularity sample to obtain a vibration-induced random track irregularity sample;

[0075] S5, inputting the earthquake-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupling system calculation model, respectively, to obtain two sets of train-track-bridge coupling dynamic response results;

[0076] S6, using the earthquake-induced damage value of the track-bridge system components as a first parameter; subtracting the two sets of train-track-bridge coupled dynamic response results to obtain a train-track-bridge coupled dynamic response result, and using the train-track-bridge coupled dynamic response result as a second parameter;

[0077] S7, training the pre-built model architecture using the first parameter and the second parameter, thereby establishing a quantitative mapping relationship between structural earthquake-induced damage and driving performance of the track-bridge system;

[0078] It is understandable that

[0079] S1, establish a train-track-bridge coupling system calculation model including: train model, track model and bridge model;

[0080] The train model includes a car body and a bogie. A single bogie consists of four wheel sets, a primary suspension, and a secondary suspension. The single-section train model is specifically divided into a car body, two frames, and four wheel sets, a total of seven rigid bodies. Each rigid body has five degrees of freedom: lateral movement, sinking and floating, rolling, nodding, and shaking, for a total of 35 degrees of freedom. Figure 2 As shown in the figure, d0 is the fixed distance of the vehicle; d1 is the fixed wheelbase; W, T are the wheelset and frame respectively; k p and C p are the suspension stiffness and damping respectively; k s , C s The train dynamics model was established using the multi-body dynamics software SIMPACK. A parametric modeling approach was employed, with the train body, front and rear bogies, and four wheelsets simulated as rigid bodies. The primary and secondary suspension systems were simulated using spring-damper technology. The mechanical and geometric parameters of the various components of the vehicle under study were input into predefined variable groups. This allows for rapid changes to different vehicle models by modifying the values ​​of the parameter variable groups, depending on the research requirements.

[0081] The track model, as shown in the attached Figure 3 The figure shows a CRTSⅠ type double-block ballastless track, which includes a base plate, an isolation layer and a limit groove, a track plate, a fastener layer, and a rail from bottom to top. The track can be built using ANSYS finite element software, where the base plate, track plate, and rail can be simulated using the Timoshenko beam BEAM188 element, and the isolation layer, limit groove, fasteners, and other interlayer connection components can be simulated using the nonlinear spring COMBIN39 element.

[0082] The bridge model is as shown in the attached Figure 4As shown, it is mainly a simply supported beam bridge, which includes foundation, abutment, piers, supports and main beam from bottom to top. The bridge can be simulated using ANSYS finite element software, where the foundation, abutment, piers and main beam are simulated using Timoshenko beam BEAM188 elements, and the bridge supports are simulated using nonlinear spring COMBIN39 and COMBIN40 elements.

[0083] The train-track-bridge coupling system calculation model is formed by the train model, the track model, and the bridge model based on the wheel-rail interaction between the train and the track, and the bridge-rail interaction between the track and the bridge. The wheel-rail interaction is divided into the normal action and the tangential action between the wheelset and the rail. The wheel-rail normal action is calculated using the nonlinear Hertz contact theory, and the wheel-rail tangential creep action is calculated using the Kaller theory. The specific calculation formula is as follows:

[0084] According to Hertz contact theory, the maximum contact pressure p in the contact spot of two smooth surface objects is max It can be obtained from formula (1):

[0085]

[0086] Where: P is the normal load of the contact patch; m, n, A, and B are constants related to the wheel-rail contact geometry; G* is the material physical parameter, which is determined by the following formula (2):

[0087]

[0088] Where, E1 is the elastic modulus of the steel wheel; E2 is the elastic modulus of the rail; v1 is the Poisson's ratio of the steel wheel; v2 is the Poisson's ratio of the rail;

[0089] The wheel-rail longitudinal and transverse creep effects are analyzed using the Kaller theory;

[0090] The calculation formulas for wheel-rail creep rate and creep force are:

[0091] Transverse creep rate:

[0092]

[0093] Longitudinal creep rate:

[0094]

[0095] Creep force:

[0096] F r =-fξ (5)

[0097] In the above formula, v x is the actual forward speed of the wheel; v xris the pure rolling forward speed of the wheel; v y Actual lateral speed of the wheel; v yr is the pure rolling lateral velocity of the wheel; b is half the distance between the rolling circles of the left and right wheels; r0 is the nominal radius; λ0 is the equivalent slope of the tread; ψ, is the wheel set pitch angle; Ω is the forward speed of the wheelset;

[0098] The bridge-rail interaction is mainly the connection between the main beam and the base plate, which is a rigid connection;

[0099] The train-track-bridge coupled system calculation model was implemented through a joint simulation using ANSYS and SIMPACK. The specific steps are as follows:

[0100] ①Generation of CDB files for geometric mesh information of the track-bridge finite element model: Generate separate CDB files for the finite element models of the main components, such as rails, track plates, base plates, main beams, and bridge piers, in ANSYS;

[0101] ② Generation of SUB files for substructure analysis of the track-bridge finite element model: Based on the CDB files of each component, perform substructure analysis solution settings in ANSYS. The solution results should include the finite element model stiffness and mass matrix and the lumped mass matrix. Based on the modal superposition theory, set the main nodes and main degrees of freedom of the finite element model. After the solution, generate the SUB files of each component.

[0102] ③ Generation of flexible body FBI files of finite element models: Based on the CDB and SUB files of each component, a flexible body FBI file containing information such as node degrees of freedom, super element mass, and stiffness matrix of each component is generated in SIMPACK;

[0103] ④ Prepare the FTR flexible track foundation file: When preparing the FTR flexible track foundation file, the track structure is spliced ​​in sections in the FTR file by setting the call and assembly rules of the FBI files of individual components such as rails, trackbed plates, and base plates. In addition, the transition section between the elastic rails on the main beam and the rigid rails in SIMPACK should be set in the FTR file, and the stiffness and damping should be set for it; and the tolerance, stiffness, and quality screening values ​​should be set;

[0104] ⑤Import the track structure FTR file into the SIMPACK model with the vehicle model already built;

[0105] ⑥ Import the FBI files of main beams, piers and other components into the vehicle-track coupling model of SIMPACK and position them;

[0106] ⑦ Create marker points on each component in SIMPACK;

[0107] ⑧Set force elements between the marker points of different components to achieve the connection between bridge structures (such as fasteners, supports, etc.);

[0108] S2, numerical acquisition of earthquake-induced damage to components of the track-bridge system, including: numerical calculation methods and post-earthquake data query methods;

[0109] The numerical calculation method is as follows: by adopting the method of artificially synthesizing seismic waves or the method of amplitude modulation of natural seismic waves, random seismic waves are generated that take into account the site characteristics. The site type of the generated seismic waves must match the building site, and according to the requirements of the "Code for Seismic Design of Buildings", the error between the average value of several seismic wave response spectra and the standard response spectrum is within ±20%, as shown in the attached figure. Figure 5 As shown; the generated seismic waves are then substituted into the established train-track-bridge coupling calculation model, and the earthquake-induced damage values ​​of the track-bridge system components can be obtained through calculation;

[0110] The post-earthquake data query method is as follows: the earthquake damage data of the track-bridge system recorded after the earthquake occurred in previous years can be queried and used as the input earthquake damage value of the track-bridge system components;

[0111] S3. Obtaining the mapping relationship between earthquake-induced damage to key track-bridge components and track irregularities includes:

[0112] First, the basic assumptions of the theoretical model of the track-bridge structure are determined. Then, based on the mechanical properties of the track-bridge structure, the equilibrium differential equations of the bridge and track structure mechanical models are constructed. The deformation of each component is then solved. The deformation equations of the track and bridge components are then linked through the forces acting on the system's interlayer components. This allows the mapping relationship between the earthquake-induced damage deformation of different interlayer components and the rail deformation to be solved.

[0113] The basic assumptions of the track-bridge structure theoretical model mainly include:

[0114] ① Ignore the impact of track on bridge deformation;

[0115] ② The inter-layer components of the track, such as the fastener system, are assumed to be springs uniformly distributed along the centerline of the rail;

[0116] ③ Consider that the track in the roadbed section has sufficient track extension sections, and assume that the track boundary of the extension section is simply supported;

[0117] ④ It is considered that the deformation of the base plate is consistent with that of the bridge;

[0118] According to the track structure mechanics model, the mechanical equilibrium differential equation of the rail is established and the expression (6) of the rail deformation is obtained by solving it, as shown below:

[0119]

[0120] Y ri is the deformation at the rail fastener position; E r I r is the bending stiffness of the rail; l MNK+1 is the total length of the rail; F j is the fastener spring force, l i is the distance from the rail end point to the i-th fastener force; M is the number of bridge spans; N is the number of main beam track plates per span; K is the number of fasteners per track plate.

[0121] From formula (6), the matrix expression of rail deformation can be obtained as follows:

[0122] [Y r ]=[R][F] (7)

[0123] In the formula, [Y r ] is the rail deformation matrix; [R] is the rail fastener spring force coefficient matrix; [F] is the fastener spring force matrix;

[0124] According to the track structure mechanics model, the mechanical equilibrium differential equation of the track plate is established, and the expression (8) of the deformation of a single track plate is obtained by solving it, as shown below:

[0125]

[0126] Where Y smi is the deformation of the mth track plate at the fastener position; F mj is the spring force of the fastener at the jth fastener position of the mth track plate; Y bm (x) is the displacement of the main beam at the position of the mth track plate; l mi is the distance from the track plate end point to the i-th fastener force; d m1 with d m2 are the distances between the end point of the limiting groove and the left end point of the track plate; k d is the stiffness of the isolation layer; k g is the stiffness of the elastic pad; A m1 , A m2 With A m3 is a constant;

[0127] Given the deformation of each position of the mth track plate, the deformation of the M×N track plates on the M-span main beam can be organized into the following matrix form:

[0128] [Y s ]=[S][F]+[C] (9)

[0129] In the formula, [Y s] is the deformation matrix of M×N track plates; [S] is the fastener spring force coefficient matrix of the track plate; [F] is the fastener spring force matrix of the track plate; [C] is the influence matrix of the main beam deformation on the track plate deformation;

[0130] The displacement expression of the bridge main beam is as follows:

[0131]

[0132] Where Y bi is the displacement of any position of the main beam of span i; h i1 is the residual displacement of the left end support of the main beam of span i; is the main beam deflection angle; L b is the total length of a single span of a simply supported beam bridge; L b0 is the distance from the support to the beam end; d is the distance between the expansion joints of the simply supported beams; X i is the distance from the point on the main beam of span i to the coordinate origin;

[0133] Under the action of horizontal deformation, the fastener spring force can be expressed as:

[0134] [F]=k r ([Y s ]-[Y r ]) (11)

[0135] Where k r is the fastener stiffness;

[0136] Substituting equations (7), (9) and (10) into equation (11), we can obtain:

[0137] [F]=([I]-k r [S]+k r [R]) -1 k r [C] (12)

[0138] Substituting formula (12) into formula (7), we can obtain the mapping deformation expression of the rail:

[0139] [Y r ]=[R]([I]-k r [S]+k r [R]) -1 k r [C] (13)

[0140] Since the mapping model between bridge structure deformation and track surface geometry has many nodes and heavy computational workload, the track deformation can be solved using MATLAB. The solution process is as follows: Figure 6 As shown;

[0141] S4, acquisition of earthquake-induced track random irregularity samples includes:

[0142] First, determine the initial track irregularity power spectrum, such as the German railway track irregularity power spectrum, the British railway track irregularity power spectrum, and the Chinese high-speed railway ballastless track irregularity power spectrum. This embodiment uses the Chinese high-speed railway ballastless track irregularity spectrum as an example. The power spectrum is represented in the form of a piecewise power function, which can better describe the distribution characteristics of ballastless track irregularities at different frequencies:

[0143] S(f)=Af -k (14)

[0144] Where, f is the spatial frequency (1 / m); A is the fitting coefficient;

[0145] Secondly, based on the selected initial track irregularity power spectrum, the initial track geometric irregularity samples are generated by numerical methods. Here, the trigonometric series superposition method is used. This method can quickly generate track irregularity samples with a specific power spectrum density. The calculation formula is as follows:

[0146]

[0147] Where w(x) represents the generated track irregularity random sample sequence; x is the mileage from the coordinate origin to the track extension position; S(f k ) is the selected track irregularity power spectrum; f k Indicates the spatial frequency of the power spectrum. When k = 1, N, it indicates the upper and lower cutoff limits of the spatial frequency of the orbital spectrum; Φ k represents the random phase corresponding to the k-th spatial frequency, which is randomly generated according to a uniform distribution and ranges from 0 to 2π; Δf represents the bandwidth of the spatial frequency interval;

[0148] Substitute the earthquake-induced damage values ​​of the track-bridge system into the mapping relationship between earthquake-induced damage of key track-bridge components and track irregularity to obtain additional track irregularity samples;

[0149] Finally, the initial track irregularity samples and the additional track irregularity samples are superimposed to obtain the vibration-induced random track irregularity samples, such as Figure 7 As shown;

[0150] S5, two sets of train-track-bridge coupled dynamic response results are obtained, including:

[0151] First, through the above steps, samples of random track irregularities induced by earthquakes and samples of initial track irregularities were obtained. These samples were then substituted into the established train-track-bridge coupling calculation model. Finally, two sets of train-track-bridge coupled dynamic response calculation results were obtained: the calculation results for only the initial track irregularities as input, and the calculation results for the superimposed earthquake-induced track irregularities as input.

[0152] S6, obtaining the first parameter and the second parameter includes:

[0153] First, the track-bridge system earthquake-induced damage value obtained above is used as the first parameter. Second, the two sets of train-track-bridge coupled dynamic response results obtained above are subtracted to obtain the train-track-bridge coupled dynamic response result corresponding to the track-bridge system earthquake-induced damage, which is used as the second parameter.

[0154] S7, training the pre-built model architecture using the first parameter and the second parameter to establish a quantitative mapping relationship between the structural earthquake-induced damage and the driving performance of the track-bridge system includes:

[0155] Using deep learning, a key implementation method in artificial neural networks, a quantitative mapping relationship is established between earthquake-induced damage to track-bridge structures and traffic safety and stability indicators. The values ​​of earthquake-induced damage to track-bridge structures include structural damage under different earthquakes. Finally, based on the established quantitative mapping relationship, train traffic safety and stability indicators are predicted, and the earthquake-induced damage threshold of the track-bridge structure is determined.

[0156] Specifically, the analysis process of deep learning is as follows: Figure 8 As shown, the basic steps are as follows:

[0157] (1) Data collection and preprocessing

[0158] First, based on the values ​​obtained in steps B and F, a preliminary dataset for deep learning is established. Second, the dataset is cleaned and denoised to ensure that the earthquake-induced damage data of the track-bridge system and the train-track-bridge coupled dynamic response data are completely caused by the earthquake, including the extremely small deformation data generated by the track-bridge system under its own weight. Data preprocessing can also improve data quality and availability, making subsequent analysis more accurate and reliable. Finally, the data is divided into training, validation, and test sets. This division helps to build, optimize, and evaluate machine learning models and ensure their generalization ability on unknown data. The general division ratio is: 60%-70% for training set, 15%-20% for validation set, and 15%-20% for test set.

[0159] (2) Design model architecture

[0160] First, based on the characteristics and type of the data, we select an appropriate deep learning model architecture, such as a multi-layer perceptron (MLP), convolutional neural network (CNN), or recurrent neural network (RNN). Based on the characteristics of this research direction, we use the MLP as an example of a deep learning model framework. The basic MLP architecture consists of an input layer, hidden layers, and an output layer. The MLP process can be divided into two phases: forward propagation and backward propagation.

[0161] Secondly, design the structure of the MLP, including the number of layers, number of nodes, and activation function; ① Number of layers: Set 3-5 hidden layers. Shallow networks have the advantages of fast training speed and easy debugging; ② Number of nodes: The number of nodes in the hidden layer is usually set according to the number of input features and the complexity of the task. Generally speaking, the number of nodes should not be less than the number of input features; the rule of thumb is to start with a larger number of nodes (for example, 128, 256, 512), and then adjust according to the performance of the model; ③ Activation function: Commonly used activation functions include Relu, Sigmoid, and Tanh. Compared with the Sigmoid function, which maps the input to the [0, 1] interval, the Tanh function's mapping output range is [-1, 1], which is more in line with the output range of the data. Therefore, this embodiment uses the Tanh function as the activation function. The formula is as follows:

[0162]

[0163] (3) Model training

[0164] First, the designed deep learning model is trained using the training dataset, and the model parameters are continuously adjusted through the back-propagation algorithm to minimize the loss function;

[0165] Then, consider training techniques such as optimization algorithms and learning rate adjustment strategies to improve the training efficiency and performance of the model. To improve the training efficiency and performance of deep learning models, the Adam optimization algorithm can be used in combination with momentum and adaptive learning rate to dynamically adjust the learning rate.

[0166] Finally, monitor indicators during the training process, such as loss value and accuracy, so as to adjust the model or training parameters in a timely manner. Common methods include recording the loss value and accuracy of the training set and validation set at the end of each training cycle (epoch), and visually observing the performance changes of the model by drawing loss curves and accuracy curves.

[0167] (4) Model evaluation and tuning

[0168] First, run the model through the validation set to calculate performance indicators such as loss value and accuracy;

[0169] Then, analyze the indicators and evaluate the results. Based on the evaluation results, adjust the model structure (such as the number of layers and nodes) and training parameters (such as learning rate and regularization strength), and further optimize them using techniques such as cross-validation and hyperparameter search.

[0170] Finally, through iterative evaluation and tuning, the performance and generalization ability of the model are gradually improved.

[0171] (5) Model preservation and application

[0172] Use the test set to test the final tuned model, evaluate its performance on unknown real data, analyze the test results, summarize the advantages and disadvantages of the model, and further improve and save the model as needed. Save the trained model as a formula or program and apply it to actual scientific problems, such as prediction tasks.

[0173] Let the track-bridge component seismic damage matrix obtained by S2 be D, which includes the seismic damage to the piers, bearings and track components of the track-bridge system;

[0174] Assume that the weight matrix obtained by deep learning is W i , W i Represented as the weight matrix of the i-th layer network structure;

[0175] Let the bias value obtained by deep learning be J i , J i Represented as the bias value of the i-th layer network structure;

[0176] Assuming the dynamic response of the train-track-bridge output by the model is V, the corresponding relationship between the earthquake-induced damage of the track-bridge system components and the driving response is as follows:

[0177] V=T(T(T(DW1+J1)W2+J2)W3+J3)W4+J4 (17)

[0178] Where T(·) represents the Tanh function transformation of the matrix;

[0179] It is worth emphasizing that the premise of this formula is to set up 3 hidden layers and no activation function is set in the output layer. The specific situation can be transformed accordingly as needed, and this application does not impose any restrictions on this.

[0180] Driving safety and stability indicators are selected. Driving safety indicators can be divided into indicators based on wheel-rail force criteria and indicators based on wheel-rail relative displacement criteria. Driving stability indicators mainly include train acceleration indicators and Sperling indicators. According to the "Specifications for the Evaluation and Experimental Appraisal of Locomotive and Train Dynamic Performance" and the "High-speed Railway Design Specifications", the limits of train driving safety and stability indicators can be determined as shown in Table 1 below:

[0181] Table 1

[0182]

[0183] In Table 1, Q is the lateral horizontal force of the wheelset; P is the dynamic wheel weight; ΔP is the vehicle axle weight reduction; P0 is the static axle weight; a z is the vertical vibration acceleration of the vehicle body; a y is the lateral vibration acceleration of the vehicle body; g is the acceleration due to gravity, which is generally taken as 9.8m / s 2 .

[0184] Based on the dynamic response results of the train-track-bridge output by the model and the limit values ​​of the train driving safety and stability indicators, the earthquake-induced damage threshold of the track-bridge structure is determined.

[0185] Example 2:

[0186] Figure 9 2 is a system schematic diagram of a railway bridge damage and driving performance mapping device according to another exemplary embodiment, the device comprising:

[0187] Railway-bridge coupling calculation module 1: used to establish train models of different train types using multi-rigid body dynamics theory, and to establish track models and bridge models using finite element theory; and to establish a train-track-bridge coupling system calculation model based on the train models, track models, and bridge models;

[0188] Component earthquake damage numerical acquisition module 2: used to obtain the component earthquake damage numerical value of the track-bridge system;

[0189] Track Irregularity Mapping Module 3: This module is used to set the basic assumptions of the theoretical model of the track-bridge structure and establish the equilibrium differential equations of the bridge and track structure mechanical models based on the mechanical properties of the track-bridge structure. Based on these equilibrium differential equations, the mapping relationship between seismic damage to key track-bridge components and track irregularity is obtained.

[0190] Irregularity sample acquisition module 4: used to respectively acquire initial track irregularity samples and additional track irregularity samples, and superimpose the initial track irregularity samples and the additional track irregularity samples to obtain earthquake-induced random track irregularity samples;

[0191] Coupled dynamic response module 5: used to input the earthquake-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupled system calculation model, respectively, to obtain two sets of train-track-bridge coupled dynamic response results;

[0192] Training parameter acquisition module 6: configured to use the earthquake-induced damage value of the track-bridge system components as a first parameter; subtract the two sets of train-track-bridge coupled dynamic response results to obtain a train-track-bridge coupled dynamic response result, and use the train-track-bridge coupled dynamic response result as a second parameter;

[0193] Mapping relationship acquisition module 7: used to train the pre-built model architecture through the first parameter and the second parameter, and then establish a quantitative mapping relationship between the structural earthquake-induced damage and driving performance of the track-bridge system.

[0194] Example 3:

[0195] This embodiment provides a storage medium, wherein the storage medium stores a computer program, and when the computer program is executed by a host controller, each step in the above method is implemented;

[0196] It is understandable that the storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0197] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0198] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is at least two.

[0199] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0200] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0201] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0202] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0203] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0204] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0205] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A railway bridge damage and driving performance mapping method, characterized in that: The method comprises: Using multi-rigid body dynamics theory to establish train models of different train models, and using finite element theory to establish track models and bridge models respectively; using the train models, track models, and bridge models to establish a train-track-bridge coupling system calculation model; Obtain earthquake-induced damage values ​​of components in the track-bridge system; The obtaining of earthquake-induced damage values ​​of components of the track-bridge system includes: Generating random seismic waves that take site characteristics into account by using an artificially synthesized seismic wave method or a natural seismic wave amplitude modulation method, inputting the random seismic waves into the train-track-bridge coupled system calculation model to obtain seismic-induced damage values ​​for components of the track-bridge system; or, Obtaining earthquake-induced damage data of the track-bridge system after a historical earthquake, and using the data as earthquake-induced damage values ​​of components of the track-bridge system; The basic assumptions of the track-bridge structure theoretical model are set, and the equilibrium differential equations of the bridge and track structure mechanical models are established based on the mechanical properties of the track-bridge structure. Based on the equilibrium differential equations, the mapping relationship between seismic damage to key track-bridge components and track irregularities is obtained; obtaining an initial track irregularity sample and an additional track irregularity sample respectively, and superimposing the initial track irregularity sample and the additional track irregularity sample to obtain a vibration-induced random track irregularity sample; Inputting the earthquake-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupling system calculation model respectively, and obtaining two sets of train-track-bridge coupling dynamic response results respectively; The earthquake-induced damage value of the track-bridge system components is used as a first parameter; the train-track-bridge coupled dynamic response result is obtained by subtracting the two sets of train-track-bridge coupled dynamic response results, and the train-track-bridge coupled dynamic response result is used as a second parameter; The pre-built model architecture is trained using the first and second parameters to establish a quantitative mapping relationship between structural earthquake-induced damage and driving performance of the track-bridge system.

2. The method according to claim 1, characterized in that The method of establishing train models of different train types using multi-rigid body dynamics theory and establishing track models and bridge models using finite element theory includes: The train model is obtained by using a rigid body to simulate the train body, front and rear bogies and four wheel sets, and using a spring-damper to simulate the primary and secondary suspension systems of the train. The track model is obtained by using spatial beam elements or plate elements to simulate the base plate and track plate of the track, using spatial beam elements to simulate the rails of the track, and using spring-damper elements to simulate the inter-layer connection components of the track. The spatial beam unit is used to simulate the foundation, abutment, piers and main beam of the bridge, and the spring-damper is used to simulate the support of the bridge to obtain the bridge model.

3. The method according to claim 2, characterized in that The establishing of a train-track-bridge coupling system calculation model by using the train model, track model, and bridge model includes: The train model, track model and bridge model are used to obtain the wheel-rail interaction between the train and the track, and between the track and the bridge, as well as the bridge-rail interaction; based on the wheel-rail interaction between the train and the track, and between the track and the bridge, a train-track-bridge coupling system calculation model is established; The wheel-rail interaction includes: normal action and tangential action between the wheelset and the rail; The normal action is obtained by using nonlinear Hertz contact theory, and the tangential action is obtained by using Kaller theory; The bridge rails interact with each other to connect the main beam and the base plate.

4. The method according to claim 3, characterized in that The method of establishing a balanced differential equation of the mechanical model of the bridge and track structure based on the mechanical characteristics of the track-bridge structure and obtaining a mapping relationship between earthquake-induced damage to key track-bridge components and track irregularity based on the balanced differential equation includes: Establishing deformation expressions of the rails, track plates, and base plates according to the track structure mechanics model, and obtaining matrix expressions of rail deformation, track plate deformation, and base plate deformation according to the deformation expressions of the rails, track plates, and base plates; Establishing a deformation expression of the bridge girder according to the bridge structure mechanics model; Obtaining spring force expressions for components between different layers of the track structure under horizontal deformation, substituting the matrix expressions for rail deformation, track plate deformation, base plate deformation, and bridge girder deformation into the spring force expressions for components between different layers of the track structure under horizontal deformation, and solving to obtain a fastener spring force matrix under horizontal action; The fastener spring force matrix under horizontal action is substituted into the matrix expression of the rail deformation to obtain the mapping relationship between the earthquake-induced damage to the key components of the track-bridge and the track irregularity.

5. The method according to claim 1, wherein The obtaining of the initial track irregularity sample and the additional track irregularity sample comprises: Acquiring an initial track irregularity power spectrum, and generating the initial track irregularity samples by a numerical method based on the initial track irregularity power spectrum; The earthquake-induced damage values ​​of the components of the track-bridge system are input into the mapping relationship between the earthquake-induced damage of the key components of the track-bridge and the track irregularity to obtain additional track irregularity samples.

6. The method according to claim 1, characterized in that The training of the pre-built model framework using the first parameter and the second parameter to establish a quantitative mapping relationship between the structural earthquake-induced damage and the driving performance of the track-bridge system includes: Preprocessing the first parameter and the second parameter, and selecting a deep learning model based on the characteristics and type of the data; constructing a data set using the first and second parameters, and training a selected deep learning model using the constructed data set, and using the trained model as a quantitative mapping relationship model between structural earthquake-induced damage and driving performance of the track-bridge system; Inputting the earthquake-induced damage values ​​of the components of the track-bridge system to be tested into a quantitative mapping relationship model between the structural earthquake-induced damage and the driving performance of the track-bridge system, and outputting the train-track-bridge coupled dynamic response results of the track-bridge system; Driving safety and stability indicators are selected, and the seismic damage threshold of the track-bridge structure is determined based on the obtained train-track-bridge coupled dynamic response results of the track-bridge system and the driving performance indicator limits specified in the specifications.

7. A railway bridge damage and driving performance mapping device, characterized in that: The device comprises: Railway-bridge coupling calculation module: used to establish train models of different train types using multi-rigid body dynamics theory, and to establish track models and bridge models using finite element theory; and to establish a train-track-bridge coupling system calculation model based on the train models, track models, and bridge models; Component earthquake damage value acquisition module: used to obtain the component earthquake damage value of the track-bridge system; The obtaining of earthquake-induced damage values ​​of components of the track-bridge system includes: Generating random seismic waves that take site characteristics into account by using an artificially synthesized seismic wave method or a natural seismic wave amplitude modulation method, inputting the random seismic waves into the train-track-bridge coupled system calculation model to obtain seismic-induced damage values ​​for components of the track-bridge system; or, Obtaining earthquake-induced damage data of the track-bridge system after a historical earthquake, and using the data as earthquake-induced damage values ​​of components of the track-bridge system; Track irregularity mapping module: This module is used to set the basic assumptions of the track-bridge structure theoretical model and establish the equilibrium differential equations of the bridge and track structure mechanical models based on the mechanical properties of the track-bridge structure. Based on these equilibrium differential equations, the mapping relationship between seismic damage to key track-bridge components and track irregularity is obtained. An irregularity sample acquisition module is used to respectively acquire an initial track irregularity sample and an additional track irregularity sample, and superimpose the initial track irregularity sample and the additional track irregularity sample to obtain a vibration-induced random track irregularity sample; Coupled dynamic response module: used to input the vibration-induced random track irregularity samples and the initial track irregularity samples into the train-track-bridge coupled system calculation model, respectively, to obtain two sets of train-track-bridge coupled dynamic response results; A training parameter acquisition module is configured to use the earthquake-induced damage value of the track-bridge system components as a first parameter; subtract the two sets of train-track-bridge coupled dynamic response results to obtain a train-track-bridge coupled dynamic response result, and use the train-track-bridge coupled dynamic response result as a second parameter; Mapping relationship acquisition module: used to train the pre-built model architecture through the first parameter and the second parameter, and then establish a quantitative mapping relationship between the structural earthquake-induced damage and driving performance of the track-bridge system.

8. A storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by the main controller, each step of the method for mapping railway bridge damage and driving performance as described in any one of claims 1 to 6 is implemented.

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