Track-bridge system anti-seismic evaluation method, medium and equipment

Abstract

The invention relates to the technical field of railway earthquake safety, in particular to a rail-bridge system earthquake resistance evaluation method, a medium and equipment. The method comprises the following steps: establishing a finite element model of a track-bridge system; carrying out nonlinear time-history analysis on the track-bridge system under different working conditions; analyzing control factors of earthquake response of the track-bridge system; establishing a mapping relation between the seismic response of the track structure and the seismic response of the main beam; calculating the earthquake response of the main beam, and evaluating the earthquake displacement response of the track structure; and the anti-seismic evaluation of the track-bridge system is realized. Through the method, the method can be used for all high-speed railway bridge types and rails at present, the anti-seismic evaluation of the rail-bridge system based on the driving performance can be indirectly and quickly realized based on the mapping relation, a large amount of time-consuming and labor-consuming train-rail-bridge system finite element simulation calculation does not need to be carried out, and the calculation efficiency is improved. The efficiency is effectively improved, the cost is reduced, the calculation is simple and convenient, and the calculation result is accurate.

Description

Technical Field

[0001] This invention relates to the field of railway earthquake safety technology, specifically to a method, medium, and equipment for seismic assessment of track-bridge systems. Background Technology

[0002] To shorten track distances, high-speed railways utilize numerous bridges in their construction. Many of these bridges are located in earthquake-prone areas, and earthquakes can damage the high-speed railway track-bridge system. This directly impacts post-earthquake operational safety and rapid emergency response. Therefore, quickly assessing the seismic response of high-speed railway track-bridge systems is crucial.

[0003] Currently, high-speed railway bridges inevitably experience seismic responses such as relative displacement at the beam ends and acceleration of the main beam under seismic loads. Existing methods for calculating the seismic response of high-speed railway bridges generally fall into two categories: one involves establishing a refined finite element model based on the structural and site characteristics of the high-speed railway track-bridge system, inputting seismic excitation, obtaining the response results, and then analyzing them to obtain the seismic response; the other involves establishing a seismic monitoring system to identify and extract structural damage characteristics through the structural response signals during an earthquake, thereby obtaining the seismic response.

[0004] However, the aforementioned research methods require extremely high accuracy from the finite element model. Post-earthquake nonlinear time-history analysis using finite element methods is resource-intensive and time-consuming, failing to quickly assess post-earthquake damage and thus hindering rapid emergency response. Furthermore, the sheer number of monitoring devices and the complexity of daily maintenance necessitate highly specialized knowledge and skills in signal processing. Moreover, existing simplified calculation methods for the seismic response of high-speed railway bridges focus solely on the bridge structure, neglecting track structure and post-earthquake traffic performance. This approach cannot treat the high-speed railway bridge as a whole for damage analysis, compromising the accuracy of the results. In addition, recent earthquake disasters have shown that track structures are more susceptible to seismic damage than bridge structures, directly threatening the safety of traffic on the bridge.

[0005] In summary, it is necessary to provide a universal and simplified calculation method that fully considers high-speed trains, bridges, and track systems as a whole, obtains the seismic response of track-bridge structures more accurately, and quickly realizes the seismic assessment of track-bridge systems based on train performance. Summary of the Invention

[0006] The purpose of this invention is to provide a versatile, efficient, and accurate method, medium, and equipment for seismic assessment of track-bridge systems. The specific technical solution is as follows: A seismic assessment method for a track-bridge system includes the following steps: S1: Establish a finite element model of the track-bridge system of high-speed railway; S2: Based on the response spectrum, artificial seismic waves are generated as the seismic excitation of the track-bridge system, and nonlinear time history analysis is performed on the track-bridge system under different working conditions to obtain the average value of the seismic response of the track structure under each working condition. S3: Based on the average value of the seismic response of the track structure, analyze the controlling factors of the seismic response of the track structure under different working conditions; S4: Based on the aforementioned control factors, establish a mapping relationship between the seismic response of the track structure and the seismic response of the main beam; S5: The seismic response of the main beam is calculated using a nonlinear time history calculation method. Based on the mapping relationship established in S4, the seismic displacement response of the track structure is evaluated. S6: Based on the mapping relationship established in S4, set the damage limits for the main components of the bridge structure, perform seismic verification of the main components of the bridge structure, and realize the seismic assessment of the track-bridge system.

[0007] Preferably, S1 specifically includes: The track-bridge system of high-speed railways was selected as the target object. In the track-bridge system, the concrete main beam is simulated using elastic beam elements, while the base plate, track plate, and rails are simulated using tensile fracture beam elements. Based on the OpenSEES platform, this paper integrates the simulation elements used in the bridge and track structures to establish a finite element model of the high-speed railway track-bridge system that takes into account both material nonlinearity and constraint nonlinearity and can accurately simulate the structural response of the target object under seismic motion.

[0008] Preferably, S2 specifically includes: Based on the target response spectrum, the characteristic period is adjusted to generate artificial seismic waves in batches. The peak ground acceleration of each seismic wave is adjusted and used as the longitudinal and lateral seismic excitation input to the finite element model of the track-bridge system. Nonlinear time history analysis is performed on the track-bridge system under different working conditions to obtain the average value of the seismic response of the track structure under each working condition. The different working conditions are divided according to the support type and beam end connection of the track-bridge system.

[0009] Preferably, the control factors are specifically: When there are gaps between the main beams, the seismic response of the track structure is controlled by the relative displacement between the beam ends; When a connecting beam device is used at the ends of adjacent beams, the seismic response of the track structure is controlled by the acceleration of the main beam.

[0010] Preferably, S4 specifically includes: Based on the aforementioned control factors, a quantitative analysis was conducted on all possible indicators of the seismic response of the main girder that could control the seismic response of the track structure. Mathematical methods were used to perform regression analysis on the seismic response of the track structure and the seismic response of the main beam to obtain the corresponding mapping relationship.

[0011] Preferably, the mapping relationship is specifically: For track-bridge systems without a connecting beam device, the seismic response of the track structure is a power function of the relative displacement at the beam ends, and other factors do not play a controlling role. For track-bridge systems using a continuous beam assembly, the seismic response of the track structure is linearly related to the acceleration of the main beam, and other factors do not play a controlling role.

[0012] Preferably, S5 specifically includes: A nonlinear time history calculation method for bridge structures with a simplified two-degree-of-freedom system is used, while considering the influence of uncertainties in bridge parameters, to quickly calculate the seismic response of the bridge structure and obtain its seismic response index. The seismic response indicators of bridges include the relative displacement at the beam ends and the acceleration of the main beam. Based on the aforementioned mapping relationship, the seismic displacement response of the track structure can be quickly estimated using the maximum relative displacement at the beam ends and the maximum acceleration of the main beam.

[0013] Preferably, S6 specifically includes: Based on the safety limits of track deformation under different damage levels and the deformation limits of related track structures calculated from existing post-earthquake bridge traffic simulations, the limits of the obtained bridge seismic response indices are calculated in reverse according to the mapping relationship for different bridge types and track types. A nonlinear time history calculation method for bridge structures using a simplified two-degree-of-freedom system is used to quickly calculate the seismic response of piers, bearings, and the bridge itself, determine whether the seismic response index limits are met, and rapidly assess the track structure response or post-earthquake traffic performance.

[0014] The present invention also provides a readable storage medium having stored computer program instructions thereon, which, when executed by a processor, implement the seismic assessment method for track-bridge systems as described above.

[0015] The present invention also provides an electronic device, comprising: at least one processor, at least one memory, and computer program instructions stored in the memory, wherein the computer program instructions are executed by the processor as described in the seismic assessment method for track-bridge systems.

[0016] The application of the technical solution of the present invention has the following beneficial effects: A method for seismic assessment of a track-bridge system includes: S1: establishing a finite element model of the track-bridge system of a high-speed railway; S2: generating artificial seismic waves based on the response spectrum as the seismic excitation of the track-bridge system, and performing nonlinear time history analysis on the track-bridge system under different working conditions to obtain the average value of the track structure seismic response for each working condition; S3: analyzing the controlling factors of the track structure seismic response under different working conditions based on the average value of the track structure seismic response; S4: establishing a mapping relationship between the track structure seismic response and the main beam seismic response based on the said controlling factors; S5: calculating the main beam seismic response using a nonlinear time history calculation method, and evaluating the seismic displacement response of the track structure based on the mapping relationship established in S4; S6: setting damage limits for the main components of the bridge structure based on the mapping relationship established in S4, performing seismic verification calculations for the main components of the bridge structure, and realizing the seismic assessment of the track-bridge system. This method is suitable for all current high-speed railway bridge types and track forms, establishing a mapping relationship between the seismic responses of the track structure and the bridge structure through the seismic response of the track-bridge system and its influencing factors. Based on existing research on track structure damage limits based on post-earthquake train performance, damage limits for the main components of the bridge structure were set. Thus, through seismic response analysis of the bridge structure and seismic verification of the main components, and based on the aforementioned mapping relationship, seismic assessment of the track-bridge system based on train performance can be achieved indirectly and quickly. The method of this invention eliminates the need for extensive and time-consuming finite element simulation calculations of the train-track-bridge system, effectively improving efficiency, reducing costs, and simplifying calculations. Furthermore, the calculation results are relatively accurate, providing a theoretical basis for in-depth research on the train safety and seismic design of high-speed railway track-bridge systems.

[0017] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic flowchart of a seismic assessment method for a track-bridge system according to an embodiment of the present invention; Figure 2 This is the finite element model of the high-speed railway track-bridge system established in the embodiments of the present invention; Figure 3 This is a schematic diagram illustrating the seismic response of a portion of the track structure in a track-bridge system under various working conditions in embodiments of the present invention; Figure 4The following is a correspondence between the transverse bridge response of the track structure under longitudinal earthquake and the longitudinal bridge relative displacement at the beam end in an embodiment of the present invention: (a-1) is the correspondence between the relative displacement at the beam end and the fastener displacement; (a-2) is the correspondence between the relative displacement at the beam end and the CA layer displacement; (a-3) is the correspondence between the relative displacement at the beam end and the sliding layer displacement. Figure 5 This invention presents the correspondence between the transverse bridge response of the track structure under transverse earthquake and the transverse bridge relative displacement at the beam end in an embodiment of the invention, wherein: (b-1) is the correspondence between the relative displacement at the beam end and the fastener displacement; (b-2) is the correspondence between the relative displacement at the beam end and the CA layer displacement; and (b-3) is the correspondence between the relative displacement at the beam end and the sliding layer displacement. Figure 6 This invention presents the correspondence between the transverse bridge response of the track structure and the longitudinal bridge acceleration response of the main beam under longitudinal earthquake conditions in this embodiment of the invention, wherein: (c-1) is the correspondence between the main beam acceleration and the fastener displacement; (c-2) is the correspondence between the main beam acceleration and the CA layer displacement; and (c-3) is the correspondence between the main beam acceleration and the sliding layer displacement. Figure 7 This invention presents the correspondence between the transverse bridge response of the track structure and the longitudinal bridge acceleration response of the main beam under a transverse earthquake, wherein: (d-1) is the correspondence between the main beam acceleration and the fastener displacement; (d-2) is the correspondence between the main beam acceleration and the CA layer displacement; and (d-3) is the correspondence between the main beam acceleration and the sliding layer displacement. Detailed Implementation

[0019] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered by the claims.

[0020] In one embodiment, see Figure 1 A seismic assessment method for a track-bridge system includes the following steps: S1: Establish a finite element model of the track-bridge system of the high-speed railway, such as Figure 2 As shown, it specifically includes: The target object is the track-bridge system of high-speed railway; the target object can be any existing bridge type and track form; The concrete main beam in the track-bridge system is simulated using elastic beam elements, while the base plate, track plate, and rails are simulated using tensile fracture beam elements. Two working conditions are provided: gaps between adjacent beam ends or the use of connecting beam devices. It is assumed that the connecting beam devices are rigidly constrained during an earthquake. The element properties of other components are defined according to the situation. Based on the OpenSEES platform, this paper integrates the simulation elements used in the bridge and track structures to establish a finite element model of the high-speed railway track-bridge system that takes into account both material nonlinearity and constraint nonlinearity and can accurately simulate the structural response of the target object under seismic motion.

[0021] S2: Based on the response spectrum, artificial seismic waves are generated as the seismic excitation for the track-bridge system, and nonlinear time history analysis is performed on the track-bridge system under different working conditions, specifically including: Based on the target response spectrum, the characteristic period is adjusted to generate artificial seismic waves in batches. The peak ground acceleration of each seismic wave was adjusted and used as the longitudinal and lateral seismic excitation input to the finite element model of the track-bridge system. Nonlinear time-history analysis was performed on the track-bridge system under different operating conditions to obtain the average value of the track structure's seismic response for each condition. Figure 3 As shown; The different working conditions are divided according to the support type and beam end connection of the track-bridge system. In this specific embodiment, there are 7 types: ordinary support without failure, ordinary support with failure, ordinary support with failure + connecting beam device, uniform friction pendulum support, concave friction pendulum support, uniform friction pendulum support + connecting beam device, and concave friction pendulum support + connecting beam device. In engineering applications, the classification can be made according to the actual situation.

[0022] S3: Based on the average seismic response of the track structure, analyze the controlling factors of the seismic response of the track structure under different working conditions, specifically including: Based on the average value of the seismic response of the track structure, the controlling factors of the seismic response of the track structure under different working conditions are analyzed. These controlling factors depend on the measurement index of the seismic response of the main beam. The control factors are specifically: When there are gaps between the main beams, the seismic response of the track structure is controlled by the relative displacement between the beam ends; When a connecting beam device is used at the ends of adjacent beams, the seismic response of the track structure is controlled by the acceleration of the main beam.

[0023] S4: Based on the aforementioned control factors, establish a mapping relationship between the seismic response of the track structure and the seismic response of the main beam, specifically including: Based on the aforementioned control factors, a quantitative analysis was conducted on all possible indicators of the seismic response of the main girder that could control the seismic response of the track structure, including but not limited to relative displacement at the girder ends and acceleration of the main girder. Mathematical methods were used to perform regression analysis on the seismic response of the track structure and the main girder to obtain the corresponding mapping relationship, such as... Figures 4-7 As shown in the figures, the coefficient of determination R of the regression formula is... 2Almost all values ​​are greater than 0.92, indicating that the mapping relationship established in this embodiment can describe the relationship between the seismic response of the track structure and the seismic response of the main beam in a good way.

[0024] The mapping relationship is specifically as follows: For track-bridge systems without a connecting beam device, the seismic response of the track structure is a power function of the relative displacement at the beam ends, and other factors do not play a controlling role. Since the beam end displacement is close to the support displacement in actual engineering, the adjacent support displacement at the beam end can be used to replace the beam end displacement. For track-bridge systems using a coupled beam assembly, the seismic response of the track structure is linearly related to the acceleration of the main beam. The acceleration of the main beam is close to the acceleration of the top surface of the support, so the acceleration of the support can be used to replace the acceleration of the main beam. Other factors do not play a controlling role.

[0025] S5: Using a nonlinear time history calculation method, the seismic response of the main beam is calculated. Based on the mapping relationship established in S4, the seismic displacement response of the track structure is evaluated, specifically including: After considering the damage or fracture of the track structure, its impact on the seismic response of the bridge structure is much smaller than the error caused by the inaccurate value of the seismic load. Without considering the influence of the track structure, the seismic response of the bridge structure is more inclined to the vibration of the bridge itself, which leads to a greater difference in vibration between adjacent bridges and is more conducive to conservatively estimating the maximum seismic response of the track structure on the bridge. A nonlinear time history calculation method for bridge structures with a simplified two-degree-of-freedom system is used, while considering the influence of uncertainties in bridge parameters, to quickly calculate the seismic response of the bridge structure and obtain its seismic response index. Using the method of this embodiment and the finite element method for track-bridge systems, the same working conditions were calculated. The results showed that the seismic response calculated by the method of this invention was greater than that calculated by the finite element method. Therefore, this method can conservatively estimate the main seismic response of the track-bridge system, which is practical and efficient. The seismic response indicators of bridges include the relative displacement at the beam ends and the acceleration of the main beam. Based on the aforementioned mapping relationship, the seismic displacement response of the track structure can be quickly estimated using the maximum relative displacement at the beam ends and the maximum acceleration of the main beam.

[0026] S6: Based on the mapping relationship established in S4, damage limits for the main components of the bridge structure are set, and seismic verification calculations are performed on the main components of the bridge structure to achieve seismic assessment of the track-bridge system. Specifically, this includes: Based on the safety limits of track deformation under different damage levels and the deformation limits of related track structures calculated by existing post-earthquake bridge traffic simulation calculations, for different bridge types and track types, the limits of the obtained bridge seismic response indicators are calculated in reverse according to the mapping relationship, including but not limited to the relative displacement limits between the longitudinal and transverse beam ends, the acceleration limits of the main beam, etc. In this embodiment, it is approximately assumed that the relative displacement between beam ends is approximately the same as the relative displacement between adjacent supports; therefore, the relative displacement limit of adjacent supports is used instead of the relative displacement limit of beam ends. Similarly, it is approximately assumed that the acceleration of the main beam is the same as the acceleration of the top surface of the supports; therefore, the acceleration limit of the top surface of the supports is used instead of the acceleration limit of the main beam. Based on the energy transfer relationship, the energy transferred from the pier to the supports must be less than the energy transferred from the earthquake to the pier; this is determined by the pier top drift ratio. ( Indicates the first The horizontal displacement of the pier top corresponding to each damage level The pier height is used to obtain the pier's limits under different damage levels. The relative displacement limits between adjacent supports and the support acceleration limits are jointly determined by the pier's own damage and the seismic response limits of the main beam. This embodiment also includes a readable storage medium storing computer program instructions that, when executed by a processor, implement the seismic assessment method for the track-bridge system as described above.

[0027] For example, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program in the electronic device.

[0028] This embodiment also includes an electronic device, comprising: at least one processor, at least one memory, and computer program instructions stored in the memory, wherein the computer program instructions are executed by the processor to perform the seismic assessment method for the track-bridge system as described above.

[0029] The electronic device can be a mobile phone, desktop computer, laptop, handheld computer, cloud server, or other computing device. The electronic device may include, but is not limited to, processors and memory. For example, the electronic device may also include input / output devices, network access devices, buses, etc.

[0030] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for seismic assessment of a track-bridge system, characterized in that, Includes the following steps: S1: Establish a finite element model of the track-bridge system of high-speed railway; S2: Based on the response spectrum, artificial seismic waves are generated as the seismic excitation of the track-bridge system, and nonlinear time history analysis is performed on the track-bridge system under different working conditions to obtain the average value of the seismic response of the track structure under each working condition. S3: Based on the average value of the seismic response of the track structure, analyze the controlling factors of the seismic response of the track structure under different working conditions; S4: Based on the aforementioned control factors, establish a mapping relationship between the seismic response of the track structure and the seismic response of the main beam; S5: The seismic response of the main beam is calculated using a nonlinear time history calculation method. Based on the mapping relationship established in S4, the seismic displacement response of the track structure is evaluated. S6: Based on the mapping relationship established in S4, set the damage limits for the main components of the bridge structure, perform seismic verification of the main components of the bridge structure, and realize the seismic assessment of the track-bridge system.

2. The seismic assessment method for a track-bridge system according to claim 1, characterized in that, S1 specifically includes: The track-bridge system of high-speed railways was selected as the target object. In the track-bridge system, the concrete main beam is simulated using elastic beam elements, while the base plate, track plate, and rails are simulated using tensile fracture beam elements. Based on the OpenSEES platform, this paper integrates the simulation elements used in the bridge and track structures to establish a finite element model of the high-speed railway track-bridge system that takes into account both material nonlinearity and constraint nonlinearity and can accurately simulate the structural response of the target object under seismic motion.

3. A seismic assessment method for a track-bridge system according to any one of claims 1 to 2, characterized in that, S2 specifically includes: Based on the target response spectrum, the characteristic period is adjusted to generate artificial seismic waves in batches. The peak ground acceleration of each seismic wave is adjusted and used as the longitudinal and lateral seismic excitation input to the finite element model of the track-bridge system. Nonlinear time history analysis is performed on the track-bridge system under different working conditions to obtain the average value of the seismic response of the track structure under each working condition. The different working conditions are divided according to the support type and beam end connection of the track-bridge system.

4. The seismic assessment method for a track-bridge system according to claim 3, characterized in that, The control factors are specifically: When there are gaps between the main beams, the seismic response of the track structure is controlled by the relative displacement between the beam ends; When a connecting beam device is used at the ends of adjacent beams, the seismic response of the track structure is controlled by the acceleration of the main beam.

5. The seismic assessment method for a track-bridge system according to claim 4, characterized in that, S4 specifically includes: Based on the aforementioned control factors, a quantitative analysis was conducted on all possible indicators of the seismic response of the main girder that could control the seismic response of the track structure. Mathematical methods were used to perform regression analysis on the seismic response of the track structure and the seismic response of the main beam to obtain the corresponding mapping relationship.

6. The seismic assessment method for a track-bridge system according to claim 5, characterized in that, The mapping relationship is specifically as follows: For track-bridge systems without a connecting beam device, the seismic response of the track structure is a power function of the relative displacement at the beam ends, and other factors do not play a controlling role. For track-bridge systems using a continuous beam assembly, the seismic response of the track structure is linearly related to the acceleration of the main beam, and other factors do not play a controlling role.

7. The seismic assessment method for a track-bridge system according to claim 6, characterized in that, S5 specifically includes: A nonlinear time history calculation method for bridge structures with a simplified two-degree-of-freedom system is used, while considering the influence of uncertainties in bridge parameters, to quickly calculate the seismic response of the bridge structure and obtain its seismic response index. The seismic response indicators of bridge structures include the relative displacement at the beam ends and the acceleration of the main beam. Based on the aforementioned mapping relationship, the seismic displacement response of the track structure can be quickly estimated using the maximum relative displacement at the beam ends and the maximum acceleration of the main beam.

8. The seismic assessment method for a track-bridge system according to claim 7, characterized in that, S6 specifically includes: Based on the safety limits of track deformation under different damage levels and the deformation limits of related track structures calculated from existing post-earthquake bridge traffic simulations, the limits of the obtained bridge seismic response indices are calculated in reverse according to the mapping relationship for different bridge types and track types. A nonlinear time history calculation method for bridge structures using a simplified two-degree-of-freedom system is used to quickly calculate the seismic response of piers, bearings, and the bridge itself, determine whether the seismic response index limits are met, and rapidly assess the track structure response or post-earthquake traffic performance.

9. A readable storage medium, characterized in that, It stores computer program instructions that, when executed by a processor, implement the seismic assessment method for track-bridge systems as described in any one of claims 1 to 8.

10. An electronic device, characterized in that, include: At least one processor, at least one memory, and computer program instructions stored in the memory, wherein the computer program instructions are executed by the processor as described in any one of claims 1 to 8, for seismic assessment of a track-bridge system.

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