Railway Subgrade Dynamic Safety Assessment Method Combined with Vehicle-Track Coupling Analysis

Abstract

The present invention discloses a method for evaluating the dynamic safety of railway subgrades in combination with vehicle-track coupling analysis, which relates to the technical field of safety evaluation and includes: retrieving to obtain K unit train formation models of K passing trains and K train-related parameter information; detecting the track state to obtain the track geometric flatness spectrum; obtaining the subgrade mechanical parameter information of the local subgrade; establishing a subgrade-rail coupling model; integrating the K unit train formation models into the subgrade-rail coupling model to obtain a vehicle-track coupling dynamics model; using the target construction task to drive the vehicle-track coupling dynamics model to simulate the external disturbance of the subgrade, and outputting the critical condition space as the evaluation result of the railway subgrade safety. The present invention solves the technical problem that the existing technology is not accurate enough in evaluating the dynamic safety of railway subgrades, and achieves the technical effect of improving the accuracy of the dynamic safety evaluation of railway subgrades by establishing a vehicle-track coupling dynamics model and simulating external disturbances.

Description

Technical Field

[0001] The present invention relates to the technical field of safety assessment, and particularly to a method for dynamically assessing the safety of railway subgrades by combining vehicle-track coupling analysis. Background Art

[0002] With the continuous expansion of the railway transportation network and the increase in train operation speed, the dynamic safety assessment of railway subgrades has become particularly important. As an important supporting structure for train operation, railway subgrades are long-term affected by various external factors such as train loads, natural environment impacts, and construction disturbances, and are prone to problems such as settlement, deformation, and reduced stability. Ensuring the safety of railway subgrades in a complex dynamic environment is crucial for guaranteeing the stability of train operation and reducing operation risks.

[0003] However, existing methods for dynamically assessing the safety of railway subgrades mainly rely on static mechanical analysis or limited monitoring data for prediction, lacking accurate dynamic modeling of the interaction between trains, tracks, and subgrades, and it is difficult to effectively simulate the dynamic impacts of external disturbances (such as construction vibrations, earthquakes, etc.) on subgrades during train operation. Traditional methods have insufficient assessment of subgrade responses under different construction disturbance scenarios, resulting in deviations in assessment results and making it difficult to provide a reliable basis for construction optimization and risk control. Summary of the Invention

[0004] This application provides a method for dynamically assessing the safety of railway subgrades by combining vehicle-track coupling analysis to address the technical problem of inaccurate assessment of the dynamic safety of railway subgrades in the prior art.

[0005] In view of the above problems, this application provides a method for dynamically assessing the safety of railway subgrades by combining vehicle-track coupling analysis.

[0006] This application provides a method for dynamically assessing the safety of railway subgrades by combining vehicle-track coupling analysis, and the method includes:

[0007] Perform associated retrieval of passing trains based on the railway line code of the railway traversed by the target construction area to obtain K unit train formation models of K passing trains and K train associated parameter information; detect the track status of the target construction area to obtain the track geometric flatness spectrum of the local traversed railway; through the investigation of the subgrade soil characteristics of the local traversed railway, obtain the subgrade mechanical parameter information of the local subgrade; taking the railway line code as the modeling benchmark, perform subgrade simulation coupling based on the track geometric flatness spectrum and subgrade mechanical parameter information to establish a subgrade-rail coupling model; according to the K train associated parameter information, integrate the K unit train formation models into the subgrade-rail coupling model to obtain a vehicle-rail coupling dynamics model; drive the vehicle-rail coupling dynamics model with the target construction task, perform subgrade external disturbance simulation, and output the critical condition space as the railway subgrade safety evaluation result.

[0008] In a possible implementation manner, driving the vehicle-rail coupling dynamics model with the target construction task to perform subgrade external disturbance simulation and outputting the critical condition space as the railway subgrade safety evaluation result includes: performing historical disturbance retrieval based on the target construction task to obtain construction external disturbance data; using the construction external disturbance data to drive the vehicle-rail coupling dynamics model to perform railway subgrade dynamic simulation to obtain the critical condition distributions of multiple external disturbance scenarios; performing linear interpolation processing on the critical condition distributions of the multiple external disturbance scenarios and outputting the critical condition space; using the critical condition space as the railway subgrade safety evaluation result of the railway traversed by the target construction area.

[0009] In a possible implementation manner, performing associated retrieval of passing trains based on the railway line code of the railway traversed by the target construction area to obtain K unit train formation models of K passing trains and K train associated parameter information includes: performing passing train retrieval according to the railway line code and outputting the train timetable; aggregating the train timetable to obtain K passing trains; based on the train types of the K passing trains, calling and obtaining K unit train formation models and K train associated parameter information from the vehicle manufacturing factory.

[0010] In a possible implementation manner, taking the railway line code as the modeling benchmark and performing subgrade simulation coupling based on the track geometric flatness spectrum and subgrade mechanical parameter information to establish a subgrade-rail coupling model includes: retrieving the unit track model according to the railway line code; replicating and connecting the unit track model based on the track geometric flatness spectrum to obtain the local rail model; using the local rail model as the basic model and performing subgrade simulation coupling on the local rail model according to the subgrade mechanical parameter information to establish the subgrade-rail coupling model.

[0011] In a possible implementation, the train-related parameter information includes train operation dynamic information, train static parameter information, and train operation formation information.

[0012] In a possible implementation, based on the K train-related parameter information, the K unit train formation models are integrated into the subgrade-rail coupling model to obtain a vehicle-rail coupling dynamics model, including: extracting first train static parameter information, first train operation dynamic information, and first train operation formation information from the first train-related parameter information of the first passing train; defining the physical properties of the first unit train formation model by applying the first train static parameter information to obtain a first unit train physical model; using the first train operation formation information and the first train operation dynamic information as simulation constraints to control the dynamics simulation of the first unit train physical model in the subgrade-rail coupling model to obtain a first train dynamics model; integrating the second unit train formation model into the first train dynamics model according to the second train-related parameter information to obtain a second train dynamics model; and so on. Through superimposed simulation, based on the K-2 train-related parameter information, the dynamic characteristics of the K unit train formation models are successively integrated into the subgrade-rail coupling model to complete the construction of the vehicle-rail coupling dynamics model.

[0013] In a possible implementation, using the first train operation formation information and the first train operation dynamic information as simulation constraints to control the dynamics simulation of the first unit train physical model in the subgrade-rail coupling model to obtain a first train dynamics model includes: decomposing the first train operation formation information to obtain multiple first train formation characteristics; adjusting the formation of the first unit train physical model with reference to the multiple first train formation characteristics and outputting multiple first-formed train physical models; and integrating the multiple first-formed train physical models into the subgrade-rail coupling model according to the first train operation dynamic information for train operation dynamics simulation to obtain the first train dynamics model.

[0014] In a possible implementation, the construction external disturbance data is used to drive the vehicle-track coupling dynamics model to perform dynamic simulation of the railway subgrade, and multiple critical condition distributions of multiple external disturbance scenarios are obtained, including: aggregating the construction external disturbance data to obtain various construction external disturbance characteristics of the multiple external disturbance scenarios; extracting the extreme value of the first train speed from the first train operation dynamic information; during the process of driving the vehicle-track coupling dynamics model to perform dynamic simulation of the railway subgrade by using the first construction external disturbance characteristic, the extreme value of the first train speed, and multiple first train formation characteristics, performing subgrade settlement detection to obtain the first element settlement condition distribution of the first passing train; and so on, obtaining the K-element settlement condition distributions of the K passing trains; spatially aligning the K-element settlement condition distributions and outputting the first critical condition distribution; and so on, obtaining multiple critical condition distributions of the multiple external disturbance scenarios.

[0015] In a possible implementation, obtaining the first train dynamics model further includes: evaluating the formation complexity of the multiple first train formation characteristics to obtain a dynamics simulation sequence; using the dynamics simulation sequence as a constraint, and integrating the multiple first formation train physical models into the subgrade-rail coupling model in sequence according to the first train operation dynamic information to perform train operation dynamics simulation, thereby obtaining the first train dynamics model.

[0016] In a possible implementation, performing track state detection on the target construction area to obtain the track geometric flatness spectrum of the local passing railway includes: presetting a construction disturbance correlation scale; extending the construction disturbance correlation scale with the target construction area as the starting point to delimit a target analysis area; taking the target analysis area as the boundary to delimit a track detection interval to obtain the local passing railway; and obtaining the track geometric flatness spectrum by performing track state detection on the local passing railway.

[0017] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0018] This application performs associated train retrieval based on the railway line code of the railway passed through in the target construction area, obtaining K unit train formation models and K train associated parameter information of K passing trains; detecting the track state of the target construction area to obtain the track geometric flatness spectrum of the local passing railway; through the investigation of the subgrade soil characteristics of the local passing railway, obtaining the subgrade mechanical parameter information of the local subgrade; using the railway line code as the modeling reference, performing subgrade simulation coupling based on the track geometric flatness spectrum and subgrade mechanical parameter information to establish a subgrade-rail coupling model; according to the K train associated parameter information, integrating the K unit train formation models into the subgrade-rail coupling model to obtain a vehicle-rail coupling dynamics model; using the target construction task to drive the vehicle-rail coupling dynamics model to perform subgrade external disturbance simulation, and outputting the critical condition space as the railway subgrade safety evaluation result. The present invention solves the technical problem that the prior art's evaluation of the dynamic safety of railway subgrades is not accurate enough, and through establishing a vehicle-rail coupling dynamics model and performing external disturbance simulation, achieves the technical effect of improving the accuracy of the dynamic safety evaluation of railway subgrades. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0020] Figure 1 Schematic flow chart of the method for evaluating the dynamic safety of railway subgrades combined with vehicle-rail coupling analysis provided by the embodiment of the present application;

[0021] Figure 2 Schematic flow chart of performing subgrade external disturbance simulation in the method for evaluating the dynamic safety of railway subgrades combined with vehicle-rail coupling analysis provided by the embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The present application provides a method for evaluating the dynamic safety of railway subgrades combined with vehicle-rail coupling analysis, which is used to solve the technical problem that the prior art's evaluation of the dynamic safety of railway subgrades is not accurate enough. By establishing a vehicle-rail coupling dynamics model and performing external disturbance simulation, the technical effect of improving the accuracy of the dynamic safety evaluation of railway subgrades is achieved.

[0023] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0024] It should be noted that any variations of the terms "including" and "having" are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or server that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or modules that are not clearly listed or are inherent to these processes, methods, products, or devices.

[0025] Embodiments, such as Figure 1 As shown, the present application provides a method for evaluating the dynamic safety of a railway subgrade in combination with vehicle-track coupling analysis. The method includes:

[0026] Step S100: Perform an associated search for passing trains according to the railway line code of the railway passing through the target construction area, and obtain K unit train formation models and K train associated parameter information of K passing trains.

[0027] In the embodiments of the present application, when performing an associated search for passing trains according to the railway line code of the railway passing through the target construction area, first query the train timetable on this line through the railway line code, aggregate the timetable data, and screen out K passing trains. Subsequently, based on the vehicle type information of the K passing trains screened out, call the vehicle manufacturer's database to obtain the corresponding unit train formation models and train associated parameter information. Among them, the unit train formation model refers to a train model in the railway transportation system that is composed of a locomotive head and one or more carriages combined according to certain rules and requirements and is used as a basic unit for research and management. The train associated parameter information includes train operation dynamic information, train static parameter information, and train operation formation information, which are used to accurately describe the operation state, structural characteristics, and formation method of the train.

[0028] Furthermore, in the method provided by the embodiments of the application, performing an associated search for passing trains according to the railway line code of the railway passing through the target construction area, and obtaining K unit train formation models and K train associated parameter information of K passing trains further includes:

[0029] Perform a passing train search according to the railway line code and output the train timetable; aggregate the train timetable to obtain K passing trains; based on the vehicle types of the K passing trains, call and obtain K unit train formation models and K train associated parameter information from the vehicle manufacturer.

[0030] In the embodiment of the present application, first, taking the railway line code of the railway passed through by the target construction area as the query benchmark, retrieve the passing trains in the railway operation management system or the relevant database. The railway line code is a code used to uniquely identify a specific railway line. Through this code, the train operation information on this line can be quickly queried, and a train timetable is output, which includes information such as train numbers, operation intervals, departure times, arrival times, and stopping stations of the trains.

[0031] After obtaining the train timetable, next, perform data processing on it, that is, screen out K passing trains. The core of this step lies in data aggregation, that is, extract the train information directly related to the target construction area from the timetable and exclude the trains that do not pass through this area. The screening criteria are based on the train's running track, passing time period, stopping situation, etc., to ensure that the selected trains can truly reflect the train operation situation in the construction area. Finally, K passing trains are screened out.

[0032] After determining the K passing trains, next, obtain their detailed train models and operation parameters. Specifically, first extract the vehicle type information of each train, and accordingly call the corresponding unit train formation model and train-related parameter information from the vehicle manufacturer's database or the railway vehicle file system. Among them, the unit train formation model refers to a train model in the railway transportation system that is composed of a locomotive head and one or more carriages combined according to certain rules and requirements and is used as a basic unit for research and management. The train-related parameter information includes train operation dynamic information, train static parameter information, and train operation formation information. Through this process, K unit train formation models and K train-related parameter information are obtained.

[0033] Furthermore, the method provided by the application embodiment further includes:

[0034] The train-related parameter information includes train operation dynamic information, train static parameter information, and train operation formation information.

[0035] In the embodiment of the present application, the train-related parameter information includes train operation dynamic information, train static parameter information, and train operation formation information. Among them, the train operation dynamic information includes the running speed range of the vehicle type, that is, parameters such as the maximum speed and average speed of the train under different working conditions. The train static parameter information includes parameters such as the total weight of the train, axle load distribution, and car body structure characteristics. The train operation formation information includes the head type of the train, the number of carriages, and the formation method.

[0036] Step S200: Detect the track state of the target construction area to obtain the track geometric flatness spectrum of the local passing railway.

[0037] In the embodiment of the present application, when detecting the track state of the target construction area, first preset the construction disturbance correlation scale, that is, determine the range where the construction may affect the track state, so as to reasonably evaluate the affected degree of the track. Subsequently, with the target construction area as the center, expand outward according to the preset disturbance correlation scale, so as to delimit the target analysis area and ensure that the track state detection covers all possible affected track ranges. On this basis, with the target analysis area as the boundary, further delimit the track detection interval to accurately define the local through-railway that needs to be monitored. Finally, use the track detection equipment to measure the track state in this area, and process and analyze the data to generate the track geometric flatness spectrum.

[0038] The track geometric flatness spectrum is a curve or data that describes the unevenness degree and distribution law of the track geometric shape. It can reflect the size and change frequency of geometric deviations such as height, level, alignment, and twist of the track at different positions.

[0039] Furthermore, in the method provided by the application embodiment, when detecting the track state of the target construction area to obtain the track geometric flatness spectrum of the local through-railway, it further includes:

[0040] Preset the construction disturbance correlation scale; expand the construction disturbance correlation scale starting from the target construction area to delimit the target analysis area; with the target analysis area as the boundary, delimit the track detection interval to obtain the local through-railway; obtain the track geometric flatness spectrum by detecting the track state of the local through-railway.

[0041] In the embodiment of the present application, first, a length value is preset by a technical expert according to the type of construction activities to obtain the construction disturbance correlation scale.

[0042] Next, starting from the target construction area, expand outward according to the construction disturbance correlation scale to form a new area. Specifically, based on the tangent line of the boundary of the target construction area, draw a vertical line, and use the length of this vertical line as the construction disturbance correlation scale. In this way, extend the influence range of the target construction area outward to determine the target analysis area, that is, the area occupied by the target construction area plus the construction disturbance correlation scale.

[0043] Subsequently, with the target analysis area as the boundary, delimit the track detection interval. The purpose is to determine the track segments located in the target analysis area, that is, to find those tracks that may be affected by construction disturbances. Through this process, clarify the specific monitoring area, so as to obtain the local through-railway, that is, the specific section that needs to be detected for the track state.

[0044] Finally, use an orbital inspection vehicle to detect the status of the tracks of the local through-railway. The orbital inspection vehicle is equipped with a laser measurement system and an inertial sensor to measure the geometric status of the tracks in real time, collect data on geometric deviations such as track elevation, alignment, and horizontal deviation, and finally generate an orbital geometric flatness spectrum through processing and analysis of these data.

[0045] Step S300: Obtain the subgrade mechanical parameter information of the local subgrade by conducting an investigation on the characteristics of the subgrade soil mass of the local through-railway.

[0046] In the embodiment of the present application, when conducting an investigation on the characteristics of the subgrade soil mass of the local through-railway, drill to obtain soil samples. Drilling technology is widely used in soil mass investigation, and soil samples are obtained by drilling holes at different positions and depths in the construction area. During the drilling process, the operator selects the position and depth of the holes according to the preset requirements to ensure that representative soil samples of the soil layer can be obtained, helping to understand the basic composition and hierarchical structure of the soil mass. Next, send the obtained soil samples to the laboratory for a triaxial shear test, which can test the shear strength and deformation characteristics of the soil. In the test, by applying different pressures to the soil samples, the failure situation of the soil under shear action is tested, and thus important parameters such as the shear strength and elastic modulus of the soil are obtained.

[0047] Then, conduct an unconfined compressive strength test, which mainly tests the compressive strength of the soil. In the test, by gradually applying pressure until the soil sample ruptures or deforms, the maximum compressive force that the soil mass can withstand is obtained, reflecting the bearing capacity of the soil mass. Through this process, the subgrade mechanical parameter information of the local subgrade is obtained, including parameters such as the elastic modulus, Poisson's ratio, compressive strength, and shear strength of the soil mass.

[0048] Step S400: Using the railway line code as the modeling benchmark, conduct subgrade simulation coupling based on the orbital geometric flatness spectrum and the subgrade mechanical parameter information, and establish a subgrade-rail coupling model.

[0049] In the embodiment of the present application, first, using the railway line code as the benchmark, retrieve and obtain the corresponding unit track model to ensure that the track modeling conforms to the structural characteristics of the target line. Subsequently, based on the orbital geometric flatness spectrum, construct a local rail model by copying and connecting the unit track models, so as to accurately reflect the geometric shape and unevenness characteristics of the track. Finally, based on the local rail model, combined with the subgrade mechanical parameter information, simulate the interaction between the track and the subgrade to complete the establishment of the subgrade-rail coupling model.

[0050] Furthermore, in the method provided by the embodiment of the application, using the railway line code as the modeling benchmark, conducting subgrade simulation coupling based on the orbital geometric flatness spectrum and the subgrade mechanical parameter information, and establishing a subgrade-rail coupling model, further includes:

[0051] Retrieve the unit track model according to the railway line code; replicate and connect the unit track models according to the track geometric flatness spectrum to obtain the local railway track model; use the local railway track model as the basic model, and perform subgrade simulation coupling on the local railway track model according to the subgrade mechanical parameter information to establish the subgrade-railway track coupling model.

[0052] In the embodiment of the present application, first, retrieve and obtain the unit track model from the railway engineering database or the track structure modeling software according to the railway line code. The unit track model is a representative track structure model, which includes the main components of the track such as rails, sleepers, and ballast, and defines the interaction relationships between them. Specifically, the parametric modeling method can be used to generate a unit track model that conforms to the actual line characteristics according to parameters such as the curve radius of the track, gauge, sleeper spacing, and rail specifications.

[0053] After obtaining the unit track model, next, expand the track shape according to the track geometric flatness spectrum to construct the local railway track model. The track geometric flatness spectrum is a set of data or curves that describe the unevenness of the track, including the magnitude and change frequency of geometric deviations such as elevation, level, alignment, and cross-level. By using data interpolation methods or spectrum analysis techniques, the data of the track geometric flatness spectrum is parsed into track shape information that can be used for numerical modeling. Then, by replicating and connecting the unit track models, the track geometric flatness information is superimposed on the unit track model to obtain the local railway track model.

[0054] Subsequently, perform subgrade simulation coupling on the local railway track model according to the subgrade mechanical parameter information. Specifically, the finite element method (FEM) is used to divide the subgrade into multiple discrete elements, and each element is assigned values according to the subgrade mechanical parameters to simulate the stress characteristics of different subgrade materials. Subsequently, through numerical solution methods, analyze the stress, displacement, and settlement responses of the track-subgrade system under the action of train loads, so as to realize the simulation coupling of the track and the subgrade. Finally, by integrating the local railway track model and the subgrade simulation coupling model, a complete subgrade-railway track coupling model is established. This model can simulate the dynamic interaction between the track and the subgrade under the action of train loads, and predict the deformation, settlement, and vibration characteristics of the track under different operating conditions.

[0055] Step S500: Integrate the K unit train formation models into the subgrade-railway track coupling model according to the K train-related parameter information to obtain the vehicle-track coupling dynamics model.

[0056] In the embodiment of the present application, based on K train-related parameter information, by gradually integrating K unit train formation models into the subgrade-rail coupling model, a vehicle-rail coupling dynamics model is finally established. Specifically, first, the static parameter information, operation dynamic information, and formation information of the first passing train are extracted from the train-related parameter information. These parameters are used to define the physical characteristics of the first unit train formation model, and a first unit train physical model is constructed to ensure the accurate simulation of the train structure and dynamic attributes.

[0057] Next, the operation dynamic information and formation information of the first train are used as simulation constraints to control the dynamic behavior of the first unit train physical model in the subgrade-rail coupling model, and the construction of the first train dynamics model is completed. This process calculates the interaction between the train wheelset and the track through the wheel-rail contact dynamics model, including rolling, slipping, and changes in wheel-rail contact forces, so as to simulate the dynamic impact of the train during driving on the track and subgrade.

[0058] Then, based on the train-related parameter information of the second train, using the same method as the first train, the second unit train formation model is integrated into the first train dynamics model to form the second train dynamics model. And so on, the K - 2 unit train formation models are gradually superimposed in the same way in sequence, and the dynamic characteristics are matched to ensure the coordination of the running states of all trains, the track force conditions, and the subgrade response characteristics, and finally the construction of the vehicle-rail coupling dynamics model is completed.

[0059] Furthermore, in the method provided by the application embodiment, based on the K train-related parameter information, integrating the K unit train formation models into the subgrade-rail coupling model to obtain a vehicle-rail coupling dynamics model further includes:

[0060] Extracting the first train static parameter information, the first train operation dynamic information, and the first train operation formation information from the first train-related parameter information of the first passing train; defining the physical attributes of the first unit train formation model by applying the first train static parameter information to obtain a first unit train physical model; using the first train operation formation information and the first train operation dynamic information as simulation constraints to control the dynamic simulation of the first unit train physical model in the subgrade-rail coupling model to obtain a first train dynamics model; integrating the second unit train formation model into the first train dynamics model according to the second train-related parameter information to obtain a second train dynamics model; and so on. Through superimposed simulation, based on the K - 2 train-related parameter information, the dynamic characteristics of the K unit train formation models are successively integrated into the subgrade-rail coupling model to complete the construction of the vehicle-rail coupling dynamics model.

[0061] In the embodiments of the present application, first, the first train static parameter information, the first train operation dynamic information, and the first train operation formation information are extracted from the first train-related parameter information of the first passing train. Among them, the static parameter information includes the axle load of the train, the car body mass distribution, the stiffness and damping characteristics of the suspension system. The operation dynamic information includes the speed, acceleration, wheel-rail contact force, braking characteristics, etc. of the train. The operation formation information defines the head type of the train, the number of carriages, the axle pitch distribution, and the formation mode.

[0062] Next, the static parameter information of the first train is applied to the definition of the physical properties of the first unit train formation model to establish the first unit train physical model. Specifically, by adopting multi-body dynamics modeling (MBD), the train is split into multiple independent but interacting rigid body units (such as car body, bogie, wheel set, etc.), and corresponding mass, inertia, stiffness, and damping are assigned to each unit. This physical model can accurately simulate the physical properties and structural characteristics of the train to ensure the correct calculation of the forces acting on the train during operation. The first unit train physical model is obtained through this step.

[0063] Subsequently, the operation formation information and operation dynamic information of the first train are used as simulation constraints, and the first unit train physical model is introduced into the subgrade-rail coupling model for dynamic simulation calculation to obtain the first train dynamic model. In this step, first, the operation formation information of the first train is decomposed into multiple first train formation characteristics, which describe the different components and structural characteristics of the train. According to these formation characteristics, the first unit train physical model is adjusted in formation to generate multiple first formation train physical models. Then, based on the operation dynamic information of the first train, these adjusted physical models are integrated into the subgrade-rail coupling model, and simulation is carried out through train operation dynamics simulation, and finally the first train dynamic model is obtained.

[0064] Next, according to the train-related parameter information of the second train, the second unit train formation model is integrated into the first train dynamic model to obtain the second train dynamic model. This process is similar to the first train modeling. First, according to the static parameters, operation dynamic information, and formation information of the second train, the physical model of the second train is generated. Subsequently, through the wheel-rail contact force model, the interaction force between the second train and the track is simulated and added to the first train dynamic model. In this way, the second train dynamic model is finally obtained, and the dynamic coupling between the first train and the second train is completed.

[0065] And so on. Following the same steps, gradually integrate the dynamic characteristics of the K - 2 unit train formation models into the established dynamic model for superposition simulation. Each superposition is based on the corresponding train - related parameter information. When adding a new train each time, adjust the force conditions and dynamic constraints in the existing model to ensure that the dynamic behaviors of all trains are coordinated with each other in the multi - train system. Finally, through this process, gradually integrate the dynamic characteristics of all K trains to obtain a complete vehicle - track coupling dynamic model.

[0066] Furthermore, in the method provided by the application embodiment, using the first train operation formation information and the first train operation dynamic information as simulation constraints to control the dynamic simulation of the first unit train physical model in the subgrade - railway track coupling model to obtain the first train dynamic model, it further includes:

[0067] Decompose the first train operation formation information to obtain multiple first train formation characteristics; refer to the multiple first train formation characteristics to adjust the formation of the first unit train physical model and output multiple first - formation train physical models; according to the first train operation dynamic information, integrate the multiple first - formation train physical models into the subgrade - railway track coupling model for train operation dynamic simulation to obtain the first train dynamic model.

[0068] In the embodiment of the present application, first decompose the operation formation information of the first train and extract multiple first train formation characteristics, such as formation order, number of carriages, locomotive type, carriage type, vehicle wheelbase, etc. By extracting these characteristics, the formation structure of the train and its possible impact on the track and subgrade can be accurately reflected.

[0069] Next, refer to the multiple first train formation characteristics to adjust the formation of the first unit train physical model. Based on information such as the formation order, number of carriages, and locomotive type of the train, adjust the physical properties such as mass distribution, suspension system stiffness, and damping characteristics in the first unit train physical model to ensure that the model can truly reflect the train operation state under different formation configurations. In this process, use the multi - body dynamics modeling (MBD) method to divide the train into multiple rigid body units (such as car body, bogie, wheel set, etc.) and assign appropriate physical properties to each unit to simulate its movement on the track. Through this step, finally obtain multiple first - formation train physical models, each model representing a different train formation configuration and providing a basis for subsequent dynamic simulation.

[0070] Finally, based on the operation dynamic information of the first train, such as the maximum running speed, acceleration, traction force, braking force, etc. of the train, multiple physical models of the first formation trains are integrated into the subgrade-rail coupling model for train operation dynamics simulation. In this process, by combining the physical model of the train with the track model and the subgrade model, the finite element method (FEM) and the rigid-flexible coupling dynamics method are used to simulate the dynamic response of the train under different operation conditions. During the simulation calculation process, factors such as the wheel-rail contact force of the train, the force distribution of the track, and the deformation and settlement of the subgrade are considered, and finally the first train dynamics model is obtained.

[0071] Furthermore, the method provided by the application embodiment further includes:

[0072] Evaluating the formation complexity of the multiple first train formations to obtain a dynamics simulation sequence; taking the dynamics simulation sequence as a constraint, and based on the operation dynamic information of the first train, successively integrating the multiple physical models of the first formation trains into the subgrade-rail coupling model for train operation dynamics simulation to obtain the first train dynamics model.

[0073] In the embodiment of the present application, first, the formation complexity of multiple first train formations is evaluated. This evaluation measures the formation complexity by analyzing the types of goods transported by the train. Different types of goods (such as heavy goods, light goods, liquid goods, bulk goods, etc.) have different impacts on the dynamic behavior of the train and the track system. For example, heavy goods trains usually have larger axle loads and traction force requirements, which require the train to have higher stiffness and stronger carbody connections, while light goods trains may exhibit greater vibrations and track impacts due to lighter loads. Bulk goods may increase the vibrations and uneven load distribution during train operation due to the instability of the goods themselves, thus having a more complex impact on the track and subgrade. Therefore, the formation complexity evaluation not only depends on train structure parameters such as the number of cars, car spacing, and connection methods, but also needs to evaluate their impacts on the train formation structure and dynamic response according to the type of goods. This process is simulated through multi-body dynamics modeling (MBD). By gradually introducing the formation characteristics of trains with different types of goods, the dynamic behavior of the train under different formation configurations and goods conditions is simulated, and a dynamics simulation sequence is generated. This simulation sequence provides constraint conditions for the subsequent model construction.

[0074] Next, with the dynamic simulation sequence as a constraint, based on the first train operation dynamic information (such as the maximum running speed), multiple physical models of the first formation trains are sequentially integrated into the subgrade-rail coupling model for train operation dynamic simulation. The first train operation dynamic information reflects the working conditions of the train and its performance under different working conditions. These data are collected through the train operation monitoring system (TCMS) to ensure that the actual running state of the train can be accurately reflected in the simulation. For example, heavy freight trains may need to simulate a large traction force, a high running speed, and a strong braking force, while light freight trains may run at a lower speed, and their impact on the track is mainly manifested as larger vibrations and smaller track impact forces. Therefore, first, the finite element method (FEM) is used to simulate the track and subgrade, simulate the elastic response of the track and subgrade, and use the rigid-flexible coupling dynamics method to connect the physical model of the train with the track-subgrade system to accurately simulate the vertical vibration, lateral vibration, wheel-rail contact force, and track force distribution of the train. As the number of train formations increases (for example, from five carriages to ten or thirteen carriages), the simulation model gradually considers the complexity of the connection methods between carriages, such as hard joints, soft joints, and changes in the suspension system between carriages. These factors will affect the dynamic behavior of the train and the response of the track system. Through this method, the forces exerted by the train on the track and subgrade are simulated for each different formation configuration, and it is ensured that the simulation results can provide consistency and accuracy under different formation configurations.

[0075] Finally, after gradually integrating multiple physical models of the first formation trains and conducting train operation dynamic simulation, the first train dynamic model is obtained.

[0076] Step S600: Drive the vehicle-rail coupling dynamic model with the target construction task, conduct external disturbance simulation of the subgrade, and output the critical condition space as the railway subgrade safety assessment result.

[0077] In the embodiment of the present application, first, the vehicle-rail coupling dynamic model is driven with the target construction task. By setting specific disturbance conditions in the construction task (such as the vibration and load of construction equipment), external disturbance simulation of the railway subgrade is carried out. These disturbance conditions are derived from historical disturbance data and are dynamically simulated through the driving model to simulate the possible impacts on the track and subgrade during the construction process. During this process, by analyzing different external disturbance scenarios, multiple critical condition distributions are obtained, and these distributions reflect the maximum deformation, stress, and other dynamic responses of the railway subgrade under different construction disturbances. Finally, these critical condition distributions are processed by linear interpolation to output the critical condition space, which can comprehensively represent the safety status of the railway subgrade under the disturbance conditions in the target construction area. Finally, the critical condition space is used as the railway subgrade safety assessment result.

[0078] Further, asFigure 2 As shown, in the method provided by the application embodiment, the vehicle-track coupling dynamics model is driven by the target construction task to simulate the external disturbance of the subgrade, and the critical condition space is output as the railway subgrade safety evaluation result. It further includes:

[0079] Retrieve historical disturbances according to the target construction task to obtain construction external disturbance data; drive the vehicle-track coupling dynamics model with the construction external disturbance data to perform dynamic simulation of the railway subgrade, obtain the critical condition distributions of multiple external disturbance scenarios; perform linear interpolation processing on the critical condition distributions of the multiple external disturbance scenarios, and output the critical condition space; use the critical condition space as the railway subgrade safety evaluation result of the railway passing through the target construction area.

[0080] In the embodiment of the present application, first retrieve historical disturbances according to the target construction task. The purpose of this step is to obtain the external disturbance data generated during past construction, specifically including key information such as occurrence time, duration, frequency range, and acceleration amplitude. These data are obtained by querying the construction equipment monitoring system or ground vibration monitoring instruments, or by analyzing construction records and historical data. Specifically, data mining methods are used to organize and screen the disturbance data in historical construction to identify various disturbance sources related to construction (such as vibrations of heavy machinery, blasting operations, changes in ground loads, etc.). Through this step, construction external disturbance data is obtained.

[0081] Subsequently, drive the vehicle-track coupling dynamics model with the construction external disturbance data to perform dynamic simulation of the railway subgrade. Specifically, first aggregate the construction external disturbance data and extract the construction external disturbance characteristics under multiple external disturbance scenarios. These characteristics include the type, intensity, frequency, and duration of the disturbance. Then, extract the speed extreme values from the first train operation dynamic information, that is, the highest and lowest speeds of the train under different operation conditions. On this basis, combine the speed extreme values of the first train and multiple formation characteristics to drive the vehicle-track coupling dynamics model to perform dynamic simulation of the railway subgrade. During the simulation process, perform subgrade settlement detection to obtain the first element settlement condition distribution of the first passing train, that is, the maximum settlement value generated by the train on the track and subgrade in the simulation result. Then, through the same process, simulate K passing trains in sequence to obtain the K-element settlement condition distribution, and perform spatial alignment to output the first critical condition distribution. This process is repeated for each disturbance scenario, and finally, the critical condition distributions of multiple external disturbance scenarios are obtained.

[0082] Next, linear interpolation is performed on the critical operating condition distributions of multiple external disturbance scenarios to smooth and connect the critical operating condition data obtained under different external disturbance scenarios. The purpose of this process is to interpolate and smooth the critical operating condition data under different disturbance conditions to obtain a continuous critical operating condition space. By using the linear interpolation method, based on the known critical operating condition points, the subgrade behavior under other possible operating conditions can be deduced. For example, for construction vibrations with different frequencies and durations, the critical deformations or failure modes that may occur in the subgrade under these conditions are estimated through linear interpolation. The result of this step is to obtain a critical operating condition space that comprehensively reflects the safety status of the railway subgrade under construction disturbance conditions.

[0083] Finally, the critical operating condition space is used as the railway subgrade safety assessment result of the railway traversed by the target construction area. This process outputs the final safety assessment based on the aforementioned simulation results. The critical operating condition space comprehensively shows whether the deformations, stresses, settlements, etc. of the railway subgrade reach the critical safety thresholds under different construction disturbance conditions, that is, whether there is a risk of failure.

[0084] Furthermore, in the method provided by the application embodiment, using the construction external disturbance data to drive the vehicle-track coupling dynamics model for railway subgrade dynamic simulation to obtain the critical operating condition distributions of multiple external disturbance scenarios further includes:

[0085] Aggregating the construction external disturbance data to obtain various construction external disturbance characteristics of the multiple external disturbance scenarios; extracting the extreme value of the first train speed from the first train operation dynamic information; during the process of driving the vehicle-track coupling dynamics model for railway subgrade dynamic simulation by using the first construction external disturbance characteristic, the extreme value of the first train speed, and multiple first train formation characteristics, performing subgrade settlement detection to obtain the first element settlement condition distribution of the first passing train; and so on, obtaining the K-element settlement condition distributions of the K passing trains; spatially aligning the K-element settlement condition distributions and outputting the first critical operating condition distribution; and so on, obtaining the critical operating condition distributions of the multiple external disturbance scenarios.

[0086] In the embodiment of the present application, first, the construction external disturbance data is aggregated. By collecting disturbance source data related to construction, this data includes key information such as the time of disturbance occurrence, duration, frequency range, and acceleration amplitude. Through the data acquisition system, the vibrations or load changes generated during the construction process are recorded. Using data sorting and screening methods, all disturbance data is summarized and divided into multiple external disturbance scenarios, and each scenario represents the disturbance characteristics under different construction conditions. Finally, a data set containing the external disturbance characteristics of multiple construction disturbance scenarios is obtained through this process.

[0087] Next, the maximum and minimum speeds of the first train are extracted from the first train operation dynamic information, including the maximum running speed and the minimum running speed of the train. These information help to understand the dynamic performance of the train under different running states and provide the speed condition input for the subsequent dynamic simulation.

[0088] On this basis, combining the first construction external disturbance characteristics, the first train speed extreme values, and multiple train formation characteristics, the vehicle-track coupling dynamics model is driven to conduct dynamic simulation of the railway subgrade. Specifically, by bringing all input data (including construction disturbance characteristics, train speed, and formation characteristics) into the model, the multi-body dynamics modeling (MBD) is used to simulate the interactions between the train, the track, and the subgrade. During the simulation process, special attention is paid to the subgrade settlement detection. By calculating the settlement and deformation of the subgrade under the action of construction disturbance and train load, the first element settlement condition distribution of the first passing train is obtained. The output result of this step is the settlement influence of the first train on the subgrade, which reflects the dynamic response of the train under specific construction disturbance conditions.

[0089] Next, by analogy, the K-element settlement condition distributions of K passing trains are obtained. Each train is calculated through the same dynamic simulation process as before to obtain the settlement influence of each train on the track and the subgrade. At each simulation, different train formation characteristics, operating conditions, and construction disturbance data are input to calculate the settlement and deformation conditions of each train under different disturbance conditions. Through this step, the K-element settlement condition distributions of K passing trains are finally obtained, which are used to describe the influence of multiple trains under the same construction disturbance conditions.

[0090] Then, the K-element settlement condition distributions are spatially aligned. Through coordinate system alignment, the settlement data of all trains are mapped into a unified coordinate system to ensure that the influences of each train on the track and the subgrade can be compared and combined. The purpose of this process is to integrate the settlement data of all trains in the same coordinate system to generate a complete first critical condition distribution.

[0091] Finally, through the above process, multiple critical condition distributions of multiple external disturbance scenarios are obtained. For each different construction disturbance scenario, the simulation and data processing are repeated to generate the critical condition distributions under different conditions, which provide the safety status of the railway subgrade under different construction disturbance conditions.

[0092] In the embodiments of the present application, in summary, the embodiments of the present application have at least the following technical effects:

[0093] This application performs associated retrieval of passing trains based on the railway line code of the railway passed through in the target construction area, and obtains K unit train formation models of K passing trains and K train associated parameter information; detects the track state of the target construction area to obtain the track geometric flatness spectrum of the local passing railway; through the investigation of the subgrade soil characteristics of the local passing railway, obtains the subgrade mechanical parameter information of the local subgrade; uses the railway line code as the modeling reference, and performs subgrade simulation coupling based on the track geometric flatness spectrum and subgrade mechanical parameter information to establish a subgrade-rail coupling model; according to the K train associated parameter information, integrates the K unit train formation models into the subgrade-rail coupling model to obtain a vehicle-rail coupling dynamics model; uses the target construction task to drive the vehicle-rail coupling dynamics model to perform external disturbance simulation of the subgrade, and outputs the critical condition space as the railway subgrade safety evaluation result. The present invention solves the technical problem that the existing technology is not accurate enough in the dynamic safety evaluation of railway subgrades, and achieves the technical effect of improving the accuracy of the dynamic safety evaluation of railway subgrades by establishing a vehicle-rail coupling dynamics model and performing external disturbance simulation.

[0094] It should be noted that the above order of the embodiments of the present application is only for description and does not represent the superiority or inferiority of the embodiments. And the above describes specific embodiments of this specification. The processes depicted in the drawings do not necessarily require the specific order and continuous order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0095] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0096] This specification and the drawings are only exemplary descriptions of the present application and are considered to have covered any and all modifications, variations, combinations, or equivalents within the scope of the present application. Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the present application and its equivalent technologies, the present application is intended to include these changes and modifications.

Claims

1. A railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis is characterized by: The method comprises: According to the railway line code of the railway passing through the target construction area, the passing train association search is performed to obtain K unit train formation models and K train association parameter information of the K passing trains; Performing track status detection on the target construction area to obtain a track geometric flatness spectrum of the local railway; By conducting a survey of the characteristics of the subgrade soil of the local railway, the subgrade mechanical parameter information of the local subgrade is obtained; Taking the railway line code as a modeling benchmark, performing roadbed simulation coupling according to the track geometric flatness spectrum and roadbed mechanical parameter information, and establishing a roadbed-rail coupling model; According to the K train-related parameter information, the K unit train formation models are integrated into the roadbed-rail coupling model to obtain a vehicle-rail coupling dynamic model; The vehicle-track coupling dynamics model is driven by the target construction task to simulate the external disturbance of the roadbed, and the critical working condition space is output as the railway roadbed safety assessment result.

2. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 1 is characterized in that: The vehicle-rail coupling dynamics model is driven by a target construction task to simulate external disturbances of the roadbed, and a critical working condition space is output as a railway roadbed safety assessment result. The method includes: Perform historical disturbance retrieval based on the target construction task to obtain external disturbance data of the construction; The vehicle-track coupling dynamics model is driven by the construction external disturbance data to perform a dynamic simulation of the railway subgrade, and a plurality of critical operating condition distributions of a plurality of external disturbance scenarios are obtained; Performing linear interpolation processing on the distribution of multiple critical operating conditions of the multiple external disturbance scenarios, and outputting the critical operating condition space; The critical operating condition space is used as a railway subgrade safety assessment result of the railway passing through the target construction area.

3. The method for dynamic safety assessment of railway subgrade combined with vehicle-track coupling analysis according to claim 2, characterized in that: According to the railway line code of the railway passing through the target construction area, a passing train association search is performed to obtain K unit train formation models and K train association parameter information of the K passing trains, and the method includes: Searching for passing trains according to the railway line code and outputting a train timetable; By aggregating the train schedules, K passing trains are obtained; Based on the vehicle types of the K passing trains, K unit train formation models and K train-related parameter information are obtained from the vehicle manufacturer.

4. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 1, characterized in that: Taking the railway line code as a modeling reference, performing roadbed simulation coupling according to the track geometric flatness spectrum and roadbed mechanical parameter information, and establishing a roadbed-rail coupling model, the method includes: Retrieving a unit track model according to the railway line code; According to the track geometric flatness spectrum, the unit track model is copied and connected to obtain a local rail model; The local rail model is used as a basic model, and roadbed simulation coupling is performed on the local rail model according to the roadbed mechanical parameter information to establish the roadbed-rail coupling model.

5. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 3 is characterized in that: The train-related parameter information includes train operation dynamic information, train static parameter information and train operation formation information.

6. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 5, characterized in that: According to the K train-related parameter information, the K unit train formation models are integrated into the roadbed-rail coupling model to obtain a vehicle-rail coupling dynamic model. The method includes: Extracting first train static parameter information, first train operation dynamic information and first train operation marshaling information from first train associated parameter information of a first passing train; Applying the first train static parameter information to define the physical properties of the first unit train marshaling model to obtain the first unit train physical model; Using the first train running marshaling information and the first train running dynamic information as simulation constraints, controlling the dynamic simulation of the first unit train physical model in the roadbed-rail coupling model, and obtaining a first train dynamic model; Integrating the second unit train formation model into the first train dynamics model according to the second train associated parameter information to obtain a second train dynamics model; By analogy, through superposition simulation, according to the K-2 train-related parameter information, the dynamic characteristics of the K unit train formation models are integrated into the roadbed-rail coupling model in turn to complete the construction of the vehicle-rail coupling dynamic model.

7. The method for dynamic safety assessment of railway subgrade combined with vehicle-track coupling analysis according to claim 6, characterized in that: The first train running formation information and the first train running dynamic information are used as simulation constraints to control the dynamic simulation of the first unit train physical model in the roadbed-rail coupling model to obtain a first train dynamic model, the method comprising: Decomposing the first train running marshaling information to obtain a plurality of first train marshaling features; Referring to the plurality of first train formation characteristics, adjusting the formation of the first unit train physical model, and outputting a plurality of first train formation physical models; According to the first train operation dynamics information, the plurality of first marshaling train physical models are integrated into the roadbed-rail coupling model to perform train operation dynamics simulation to obtain the first train dynamics model.

8. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 7, characterized in that: The vehicle-track coupling dynamics model is driven by the construction external disturbance data to perform a dynamic simulation of the railway subgrade, and multiple critical operating condition distributions of multiple external disturbance scenarios are obtained. The method includes: Aggregating the construction external disturbance data to obtain multiple construction external disturbance features of the multiple external disturbance scenarios; Extracting a first train speed extreme value from the first train running dynamic information; In the process of driving the vehicle-track coupling dynamics model to perform a dynamic simulation of a railway subgrade by using the first construction external disturbance feature, the first train speed extreme value and a plurality of first train formation features, a subgrade settlement detection is performed to obtain a first-element settlement condition distribution of a first passing train; By analogy, the K-yuan settlement condition distribution of the K passing trains is obtained; Spatially aligning the K-dimensional settlement condition distribution and outputting the first critical condition distribution; By analogy, multiple critical operating condition distributions of the multiple external disturbance scenarios are obtained.

9. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 7, characterized in that: The method further comprises: Performing a formation complexity evaluation on the plurality of first train formation characteristics to obtain a dynamic simulation sequence; Taking the dynamic simulation sequence as a constraint and according to the first train operation dynamic information, the multiple first marshaling train physical models are sequentially integrated into the roadbed-rail coupling model to perform train operation dynamics simulation to obtain the first train dynamics model.

10. The railway subgrade dynamic safety assessment method combined with vehicle-track coupling analysis according to claim 1, characterized in that: Performing track status detection on the target construction area to obtain a track geometric flatness spectrum of a local railway, the method comprising: Preset construction disturbance correlation scale; Taking the target construction area as a starting point, extending the construction disturbance association scale to frame the target analysis area; Taking the target analysis area as the boundary, the track detection interval is delineated to obtain the local passing railway; The track geometric flatness spectrum is obtained by performing track status detection on the local railway.

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