A high-speed railway bridge rescue evacuation passage state comprehensive evaluation method and system

Abstract

The application discloses a high-speed railway bridge rescue evacuation passage state comprehensive evaluation method, comprising the following steps: S1, obtaining appearance and shape parameter measurement results by measuring appearance and shape parameters of an evacuation passage based on unmanned aerial vehicle inspection; S2, obtaining pedestrian comfort evaluation results by evaluating pedestrian comfort of the evacuation passage based on acceleration testing; and S3, performing comprehensive evaluation on the high-speed railway bridge rescue evacuation passage state based on the appearance and shape parameter measurement results and the pedestrian comfort evaluation results. The application also discloses a system, a device, electronic equipment and a computer readable storage medium.

Description

Technical Field

[0001] This invention relates to the field of high-speed railway ancillary facilities technology, specifically to a comprehensive evaluation method and system for the status of high-speed railway bridge rescue and evacuation channels. Background Technology

[0002] As the operating mileage of high-speed railways in my country continues to increase, the number of high-speed railway bridge rescue and evacuation channels has also increased significantly. Typically, one bridge rescue and evacuation channel is set up every 3km. As an important ancillary facility of high-speed railway bridges, it is a key channel for personnel evacuation and emergency rescue in case of emergencies, and its structural condition is directly related to the operational safety of high-speed railways.

[0003] Currently, many problems have been exposed in the operation of high-speed railway bridge rescue and evacuation channels, mainly including uneven settlement and obvious swaying when pedestrians are walking. The above problems are caused by the fact that the evacuation channels designed in the plan adopt shallow foundations and have low requirements for the foundation when replacing them with pile foundations, resulting in insufficient foundation bearing capacity and defects in structural stiffness.

[0004] In existing technologies, the main methods for inspecting emergency evacuation passages on high-speed railway bridges are manual measurement and visual inspection. This includes manually measuring the height difference and gaps between the evacuation passage and the bridge, and manually observing whether there are cracks, damage, or other external defects in the structure. However, this type of inspection method has significant drawbacks: First, each evacuation passage requires a separate application for a high-speed railway maintenance window, making the inspection process cumbersome and inefficient, and difficult to meet the routine inspection needs of large-scale evacuation passages. Second, manual inspection methods are limited and lack scientific detection and evaluation methods for core issues such as uneven settlement and pedestrian swaying in evacuation passages. It is impossible to quantitatively analyze the dynamic response and stiffness state of the structure, resulting in an inability to scientifically and comprehensively assess the overall condition of the evacuation passage and to identify potential structural hazards in advance.

[0005] There is a method and system for detecting bridge rescue evacuation passages based on horizontal and vertical dynamic parameters in the existing technology. This method evaluates the bearing capacity of the foundation by comparing the horizontal natural frequency with the theoretical natural frequency and the relative magnitude of the vertical dynamic stiffness, which to some extent fills the gap in dynamic parameter detection. However, this method does not involve the detection of appearance defects and form and position parameters of the evacuation passage, nor does it evaluate pedestrian comfort, and cannot achieve a comprehensive assessment of the condition of the evacuation passage.

[0006] In summary, existing technologies lack a complete and scientific method for evaluating the status of rescue and evacuation channels on high-speed railway bridges. The detection efficiency is low and the evaluation dimensions are limited, making it difficult to meet the needs of accurate and comprehensive evaluation of the status of rescue and evacuation channels during high-speed railway operation. Therefore, there is an urgent need for a method and system that integrates multi-dimensional detection methods and can achieve comprehensive evaluation to solve the above-mentioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of existing technologies and propose a comprehensive evaluation method and system for the condition of emergency evacuation passages on high-speed railway bridges. This addresses the technical problems of low detection efficiency, lack of evaluation methods, and limited dimensions in existing evacuation passage systems. By integrating appearance and shape measurements from UAV inspections with pedestrian comfort evaluation based on acceleration testing, a comprehensive, scientific, and quantitative evaluation of the evacuation passage condition is achieved. Another objective of this invention is to provide a system for implementing the above method. This system has a reasonable structure, with modules working collaboratively, and can efficiently complete data collection, analysis, and comprehensive evaluation, providing technical support for the maintenance and repair of evacuation passages.

[0008] The first aspect of this invention is to provide a comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges, comprising: S1, Based on UAV inspection, measure the appearance and position parameters of the evacuation passage to obtain the appearance and position parameter measurement results; S2, pedestrian comfort evaluation results are obtained by evaluating pedestrian comfort in evacuation routes based on acceleration tests; S3. Based on the measurement results of the appearance and shape parameters and the evaluation results of pedestrian comfort, a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation channel is conducted.

[0009] Preferably, S1 includes: S11 integrates the inspection path of the main bridge structure into the visual inspection of evacuation passages and plans drone inspection routes for evacuation passages. S12, Set up control points and collect inspection image data; S13, Process the inspection image data to construct a three-dimensional model of the evacuation route; S14. Based on the three-dimensional model of the evacuation channel and combined with the image enhancement algorithm, measure the relative height difference between the top platform of the evacuation channel and the bridge deck operation channel, as well as the gap width between the top surface of the platform and the bridge deck shield. At the same time, identify the appearance defects of the evacuation channel and the tilt of the columns to form appearance and position parameter measurement data. S15, compare the appearance and shape parameter measurement data with historical inspection data, analyze the changing trend of structural parameters, and thus obtain the appearance and shape parameter measurement results.

[0010] Preferably, S2 includes: S21. Based on the structural form of the evacuation passage, horizontal and vertical acceleration sensors are arranged at preset measuring points to collect horizontal and vertical acceleration response data at rest platforms at different heights of the evacuation passage under the action of pedestrians, and the maximum peak acceleration of each measuring point is extracted. S22, based on the pedestrian comfort evaluation standard of the German EN03 standard, classifies and evaluates the pedestrian comfort of evacuation routes, and judges whether the dynamic response of evacuation routes in pedestrian conditions meets the normal use requirements, thereby obtaining the pedestrian comfort evaluation results.

[0011] Preferably, S3 includes: S31, a comprehensive evaluation index system is constructed based on the measurement results of the appearance and shape parameters and the evaluation results of pedestrian comfort; S32. Based on the comprehensive evaluation index system, evaluate the overall status of the high-speed railway bridge rescue and evacuation passage, generate a comprehensive evaluation report, and clarify the status level and hidden danger location of the evacuation passage.

[0012] Preferably, the specific parameters of the UAV inspection route for the evacuation channel in S11 are as follows: the flight altitude is set to 1.5 times the height of the rescue channel, the flight speed does not exceed 8m / s, the directional overlap is not less than 80%, and the lateral overlap is not less than 70%; a combination of circling flight and cross-route mode is adopted, with circling flight covering the sides and top of the channel in layers, and cross-route supplementing orthophotos; the UAV is manually controlled to take close-up photos of the area connecting the channel and the bridge surface; the data collection time avoids strong light periods and inclement weather, and the operation is carried out in the morning or afternoon when the lighting is uniform; the layout requirements of the control points in S12 are as follows: the control points are evenly distributed on the bridge surface, the channel, and the ground, and extend to 50 meters away from both ends of the bridge; the coordinate measurement error of the control points is controlled within the range of ≤2cm in plane and ≤3cm in elevation; the image quality is checked in real time during the data collection process to eliminate blurry, overexposed, or dirty images; S13 includes: S131, Data processing, including: importing image and control point data using Context Capture or Pix 4D mapper, performing multi-view joint adjustment, so that the control point plane error is ≤3cm and the elevation error is ≤5cm; S132, Point cloud generation, including: generating point clouds through a dense matching algorithm, with a point cloud density of not less than 200 points / square meter, and key parts such as bridge piers and cables being densified to 500 points / square meter, while filtering dynamic noise points such as vegetation and vehicles; S133, Mesh optimization, including: constructing a triangular mesh using a non-uniform mesh, preserving the angular features of the bridge, and manually repairing mesh holes; S134, Texture mapping, including: automatically selecting the best viewing angle image for texture mapping by software, and enabling HDR compositing or manual adjustment for reflective surfaces such as metal railings; S135, aerial triangulation solution, includes: lightweight processing of the 3D model, outputting the model in OBJ or FBX format by bridge span blocks, supporting 3D Tiles loading on the Web; comparing the total station measured coordinates with the model coordinates to verify the model accuracy, ensuring that the plane error is ≤5cm and the elevation error is ≤8cm. The relative height difference between the top platform of the evacuation passage and the bridge deck operation passage, as well as the gap width between the top surface of the platform and the bridge deck shield, as measured in S14, include: In the 3D model, corresponding measurement points are selected, and image enhancement algorithms are used to improve image brightness and contrast, highlighting the height difference and gap boundaries. The relative height difference and gap width were measured at least three times at different locations, and the average value was taken as the final measurement result. The accuracy of the measurement result was verified by on-site measurement.

[0013] Preferably, the arrangement principle of the preset measuring points in S21 is as follows: the measuring points of the sloping and turning evacuation channels are arranged at the rest platform at the mid-span and the top of the stairway, covering different height ranges of the evacuation channel from bottom to top; the sampling frequency of the accelerometer is not less than 50Hz, and the pedestrian density is ensured to match the actual use scenario during the acquisition process, simulating the pedestrian load state under normal pedestrian and emergency conditions.

[0014] Preferably, the grading evaluation of pedestrian comfort in evacuation routes according to the pedestrian comfort evaluation standard of German EN03 includes: Comfort level CL1 is the best comfort level, with peak vertical acceleration <0.50m / s² and peak lateral acceleration <0.10m / s². The comfort level CL2 is a medium comfort level, with a vertical peak acceleration of 0.50~1.00m / s² and a lateral peak acceleration of 0.10~0.30m / s². The comfort level CL3 is the tolerable comfort level, with a vertical peak acceleration of 1.00~2.50 m / s² and a lateral peak acceleration of 0.30~0.80 m / s². Comfort level CL4 is an unacceptable comfort level, with peak vertical acceleration > 2.50 m / s² and peak lateral acceleration > 0.80 m / s². The determination of whether the dynamic response of the evacuation route in pedestrian condition meets the normal use requirements includes: when the comfort evaluation result of the evacuation route is CL3 or CL4, it is determined that its dynamic response does not meet the normal use requirements.

[0015] Preferably, the comprehensive evaluation index system includes: Visual defects include cracks, damage, and concrete spalling; Geometric parameters, including relative height difference, gap width, column inclination and parameter variation trends; Comfort indicators, including: pedestrian comfort rating results; The evaluation of the overall status of the high-speed railway bridge rescue and evacuation passage based on the comprehensive evaluation index system, and the generation of a comprehensive evaluation report, includes: Based on the weights and evaluation criteria of each indicator, the overall condition of evacuation routes is divided into four levels: excellent, good, average, and unqualified. Excellent indicates no appearance defects, form and position parameters meet the specifications, and comfort is CL1. Good indicates minor appearance defects, form and position parameters are within the allowable range of the specifications, and comfort is CL1. Average indicates moderate appearance defects, form and position parameters are close to the specification limits, or comfort is CL2. Unqualified indicates severe appearance defects, form and position parameters exceed the specification limits, or comfort is CL3 / CL4.

[0016] A second aspect of the present invention provides a comprehensive evaluation system for the status of rescue and evacuation passages on high-speed railway bridges, for implementing the method of the first aspect, comprising: The appearance and shape parameter measurement unit (101) is used to measure the appearance and shape parameters of evacuation passages based on UAV inspection and obtain the appearance and shape parameter measurement results. The pedestrian comfort evaluation unit (102) is used to evaluate the pedestrian comfort of evacuation routes based on acceleration tests and obtain pedestrian comfort evaluation results. The comprehensive evaluation unit (103) is used to conduct a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation passage based on the appearance and shape parameter measurement results and the pedestrian comfort evaluation results.

[0017] A third aspect of the present invention provides a comprehensive evaluation device for the status of rescue and evacuation channels on high-speed railway bridges, used to implement the method of the first aspect, comprising: The system includes a drone inspection module, an acceleration monitoring module, a data processing module, and a comprehensive evaluation module. The outputs of the drone inspection module and the acceleration monitoring module are connected to the input of the data processing module, and the output of the data processing module is connected to the input of the comprehensive evaluation module. The UAV inspection module includes a UAV body, an aerial camera, a positioning module, and a flight path planning unit. The flight path planning unit plans inspection routes that meet parameter requirements. The positioning module enables precise positioning of the UAV. The aerial camera collects inspection image data of evacuation routes. The UAV body completes flight inspections according to the planned flight path. The aerial camera uses a high-definition industrial camera, and the positioning module uses GPS + BeiDou dual-mode positioning with a positioning accuracy of ≤1cm. The acceleration monitoring module includes a lateral acceleration sensor, a vertical acceleration sensor, a data acquisition unit, and a power supply unit. The lateral and vertical acceleration sensors are deployed at preset measuring points in the evacuation route to collect lateral and vertical acceleration response data under pedestrian influence. The data acquisition unit receives and stores the data collected by the acceleration sensors. The measurement accuracy of the lateral and vertical acceleration sensors is ±0.001 m / s², and the frequency response range is 0.1~100 Hz. The sampling frequency of the data acquisition unit is adjustable, with a maximum sampling frequency of not less than 100 Hz. The data processing module includes an image processing unit, a model building unit, an acceleration analysis unit, and a data comparison unit. The image processing unit performs image enhancement preprocessing on the inspection images. The model building unit constructs a 3D model of the evacuation route and measures its geometric parameters. The acceleration analysis unit extracts the maximum peak acceleration and performs comfort grading. The data comparison unit compares the current measurement data with historical data to analyze trends. The data processing module uses an industrial-grade server equipped with a multi-core processor and a high-performance graphics card, supporting large-scale image data processing and 3D model construction. The comprehensive evaluation module includes an indicator system construction unit, an evaluation result generation unit, and a report output unit. The indicator system construction unit is used to construct a comprehensive evaluation indicator system that integrates appearance, shape and position parameters, and comfort. The evaluation result generation unit is used to complete the overall status evaluation of the evacuation passage based on the indicator system. The report output unit is used to generate and output a comprehensive evaluation report. The comprehensive evaluation module has a built-in evaluation algorithm.

[0018] A fourth aspect of the present invention provides an electronic device including a processor and a memory, the memory storing a plurality of instructions, the processor being configured to read the instructions and execute the method as described in the first aspect.

[0019] A fifth aspect of the present invention provides a computer-readable storage medium storing a plurality of instructions which can be read by a processor and executed as described in the first aspect.

[0020] The beneficial effects of the method and system of the present invention are as follows: 1. This invention integrates drone inspection technology with routine inspection of bridge main structures, eliminating the need to apply for separate inspection windows for evacuation passages, thus significantly improving inspection efficiency. At the same time, drone inspection avoids the safety risks of manual high-altitude operations. Through high-definition image acquisition and 3D modeling, it achieves accurate measurement of appearance defects and shape and position parameters of evacuation passages. The measurement accuracy meets engineering requirements, and the trend of structural parameter changes can be analyzed by comparing historical data to achieve early identification of structural hazards.

[0021] 2. This invention fills the gap in the evaluation of pedestrian comfort in emergency evacuation passages on high-speed railway bridges. By deploying acceleration sensors to collect the lateral and vertical acceleration responses under the action of pedestrians, and combining the internationally recognized German EN03 standard, a comfort level evaluation is completed. The dynamic response of the evacuation passage under pedestrian conditions is quantitatively analyzed, which can accurately determine whether the swaying of the evacuation passage meets the requirements for normal use, and is highly consistent with the actual situation reported by the engineering department.

[0022] 3. This invention integrates the appearance and shape parameter measurement results of UAV inspections and the comfort evaluation results of acceleration tests to construct a multi-dimensional comprehensive evaluation index system. It realizes a comprehensive, scientific and quantitative assessment of the status of evacuation channels, which changes the status of existing technologies with a single evaluation dimension. It can clearly identify the status level of evacuation channels and the specific location of hidden dangers, providing a scientific basis for the routine maintenance and targeted repair of high-speed railway bridge rescue evacuation channels.

[0023] 4. The evaluation method of this invention is applicable to rescue and evacuation channels of high-speed railway bridges in service and newly built. It can achieve accurate evaluation of both slope-type and turn-type evacuation channels, and has a wide range of applications. At the same time, the system structure of this invention is reasonable, the modules work together, the data collection, processing, analysis and evaluation process is highly automated, the operation is simple, and it is easy to promote and apply in engineering practice.

[0024] 5. This invention integrates multiple technologies such as image enhancement algorithms, 3D modeling technology, and acceleration signal analysis technology to achieve a technological upgrade in the detection and evaluation of evacuation channels. Compared with traditional manual detection methods, the detection results are more accurate and comprehensive, and the evaluation results are more scientific and quantitative. It can effectively improve the operational safety level of high-speed railway bridge rescue and evacuation channels and ensure the smooth progress of personnel evacuation and emergency rescue in case of emergencies. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 A flowchart of a comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges provided in an embodiment of the present invention; Figure 2 This is a diagram illustrating the architecture of a comprehensive evaluation system for the status of rescue and evacuation channels on high-speed railway bridges, provided in an embodiment of the present invention. Figure 3This is a schematic diagram of the drone detection process provided according to an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the principle of relative height difference measurement according to an embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the principle of relative elevation difference image processing and measurement according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the arrangement of acceleration measuring points in a slope-type evacuation channel according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the acceleration measuring point arrangement of a zigzag evacuation channel according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the acceleration response of a rescue evacuation passage with a height of 11m provided according to an embodiment of the present invention, wherein... Figure 8 (a) is a schematic diagram of the lateral acceleration response of a rescue evacuation passage with a height of 11m. Figure 8 (b) is a schematic diagram of the vertical acceleration response of a rescue and evacuation passage with a height of 11m; Figure 9 The acceleration response of a rescue evacuation passage with a height of 15m provided according to an embodiment of the present invention, wherein Figure 9 (a) is a schematic diagram of the lateral acceleration response of a rescue and evacuation passage with a height of 15m. Figure 9 (b) is a schematic diagram of the vertical acceleration response of a rescue and evacuation passage with a height of 15m; Figure 10 The acceleration response of a 20m high rescue evacuation passage provided according to an embodiment of the present invention, wherein Figure 10 (a) is a schematic diagram of the lateral acceleration response of a rescue and evacuation passage with a height of 20m. Figure 10 (b) is a schematic diagram of the vertical acceleration response of a rescue and evacuation passage with a height of 20m; Figure 11 This is a schematic diagram of the test results of the lateral natural frequency of a 12.5m high evacuation passage according to an embodiment of the present invention; Figure 12 This is a schematic diagram illustrating the relationship between dynamic stiffness and static stiffness according to an embodiment of the present invention; Figure 13 This is a schematic diagram of the on-site vibration and measuring point layout of a high-speed railway bridge rescue and evacuation channel according to an embodiment of the present invention; Figure 14 This is a structural diagram of an electronic device provided according to an embodiment of the present invention. Detailed Implementation

[0027] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0030] like Figure 1 As shown, the first aspect of the present invention is to provide a comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges, comprising: S1, Based on UAV inspection, measure the appearance and position parameters of the evacuation passage to obtain the appearance and position parameter measurement results; S2, pedestrian comfort evaluation results are obtained by evaluating pedestrian comfort in evacuation routes based on acceleration tests; S3. Based on the measurement results of the appearance and shape parameters and the evaluation results of pedestrian comfort, a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation channel is conducted.

[0031] In a preferred embodiment, S1 includes: S11 integrates the inspection path of the main bridge structure into the visual inspection of evacuation passages and plans drone inspection routes for evacuation passages. S12, Set up control points and collect inspection image data; S13, Process the inspection image data to construct a three-dimensional model of the evacuation route; S14. Based on the three-dimensional model of the evacuation channel and combined with the image enhancement algorithm, measure the relative height difference between the top platform of the evacuation channel and the bridge deck operation channel, as well as the gap width between the top surface of the platform and the bridge deck shield. At the same time, identify the appearance defects of the evacuation channel and the tilt of the columns to form appearance and position parameter measurement data. S15, compare the appearance and shape parameter measurement data with historical inspection data, analyze the changing trend of structural parameters, and thus obtain the appearance and shape parameter measurement results.

[0032] In a preferred embodiment, S2 includes: S21. Based on the structural form of the evacuation passage, horizontal and vertical acceleration sensors are arranged at preset measuring points to collect horizontal and vertical acceleration response data at rest platforms at different heights of the evacuation passage under the action of pedestrians, and the maximum peak acceleration of each measuring point is extracted. S22, based on the pedestrian comfort evaluation standard of the German EN03 standard, classifies and evaluates the pedestrian comfort of evacuation routes, and judges whether the dynamic response of evacuation routes in pedestrian conditions meets the normal use requirements, thereby obtaining the pedestrian comfort evaluation results.

[0033] In a preferred embodiment, S3 includes: S31, a comprehensive evaluation index system is constructed based on the measurement results of the appearance and shape parameters and the evaluation results of pedestrian comfort; S32. Based on the comprehensive evaluation index system, evaluate the overall status of the high-speed railway bridge rescue and evacuation passage, generate a comprehensive evaluation report, and clarify the status level and hidden danger location of the evacuation passage.

[0034] As a preferred implementation, the specific parameters of the UAV inspection route for the evacuation channel in S11 are as follows: the flight altitude is set to 1.5 times the height of the rescue channel, the flight speed does not exceed 8m / s, the directional overlap is not less than 80%, and the lateral overlap is not less than 70%; a combination of circling flight and cross-route mode is adopted, with circling flight covering the sides and top of the channel in layers, and cross-route supplementing orthophotos, and the UAV is manually controlled to take close-up photos of the area where the channel connects to the bridge surface; the collection time avoids strong light periods and bad weather, and the operation is carried out in the morning or afternoon when the lighting is uniform.

[0035] As a preferred embodiment, the layout requirements of the control points in S12 are as follows: the control points are evenly distributed on the bridge deck, the passage and the ground, and extend to 50 meters away from both ends of the bridge; the coordinate measurement error of the control points is controlled within the range of ≤2cm in plane and ≤3cm in elevation; the image quality is checked in real time during the data acquisition process to eliminate blurry, overexposed or dirty images.

[0036] In a preferred embodiment, S13 includes: S131, Data processing, including: importing image and control point data using Context Capture or Pix 4D mapper, performing multi-view joint adjustment, so that the control point plane error is ≤3cm and the elevation error is ≤5cm; S132, Point cloud generation, including: generating point clouds through a dense matching algorithm, with a point cloud density of not less than 200 points / square meter, and key parts such as bridge piers and cables being densified to 500 points / square meter, while filtering dynamic noise points such as vegetation and vehicles; S133, Mesh optimization, including: constructing a triangular mesh using a non-uniform mesh, preserving the angular features of the bridge, and manually repairing mesh holes; S134, Texture mapping, including: automatically selecting the best viewing angle image for texture mapping by software, and enabling HDR compositing or manual adjustment for reflective surfaces such as metal railings; S135, aerial triangulation solution, includes: lightweight processing of the 3D model, outputting in OBJ or FBX format by bridge span, supporting 3D Tiles loading on the Web; comparing the total station measured coordinates with the model coordinates to verify the model accuracy, ensuring that the plane error is ≤5cm and the elevation error is ≤8cm.

[0037] In a preferred embodiment, the measurement of the relative height difference between the top platform of the evacuation channel and the bridge deck operation channel in S14, as well as the gap width between the top surface of the platform and the bridge deck shield, includes: In the 3D model, corresponding measurement points are selected, and image enhancement algorithms are used to improve image brightness and contrast, highlighting the height difference and gap boundaries. The relative height difference and gap width were measured at least three times at different locations, and the average value was taken as the final measurement result. The accuracy of the measurement result was verified by on-site measurement.

[0038] As a preferred embodiment, the arrangement principle of the preset measuring points in S21 is as follows: the measuring points of the sloping and turning evacuation channels are arranged at the rest platform at the mid-span and the top of the stairway, covering different height ranges from the bottom to the top of the evacuation channel; the sampling frequency of the accelerometer is not less than 50Hz, and the pedestrian density is ensured to match the actual use scenario during the acquisition process, simulating the pedestrian load state under normal pedestrian and emergency conditions.

[0039] As a preferred embodiment, the step of classifying and evaluating the pedestrian comfort of evacuation routes according to the pedestrian comfort evaluation standard of the German EN03 standard includes: Comfort level CL1 is the best comfort level, with peak vertical acceleration <0.50m / s² and peak lateral acceleration <0.10m / s². The comfort level CL2 is a medium comfort level, with a vertical peak acceleration of 0.50~1.00m / s² and a lateral peak acceleration of 0.10~0.30m / s². The comfort level CL3 is the tolerable comfort level, with a vertical peak acceleration of 1.00~2.50 m / s² and a lateral peak acceleration of 0.30~0.80 m / s². Comfort level CL4 is an unacceptable comfort level, with peak vertical acceleration > 2.50 m / s² and peak lateral acceleration > 0.80 m / s². The determination of whether the dynamic response of the evacuation route in pedestrian condition meets the normal use requirements includes: when the comfort evaluation result of the evacuation route is CL3 or CL4, it is determined that its dynamic response does not meet the normal use requirements.

[0040] As a preferred implementation, the comprehensive evaluation index system includes: Visual defects include cracks, damage, and concrete spalling; Geometric parameters, including relative height difference, gap width, column inclination and parameter variation trends; Comfort indicators, including: pedestrian comfort rating results; The evaluation of the overall status of the high-speed railway bridge rescue and evacuation passage based on the comprehensive evaluation index system, and the generation of a comprehensive evaluation report, includes: Based on the weights and evaluation criteria of each indicator, the overall condition of evacuation routes is divided into four levels: excellent, good, average, and unqualified. Excellent indicates no appearance defects, form and position parameters meet the specifications, and comfort is CL1. Good indicates minor appearance defects, form and position parameters are within the allowable range of the specifications, and comfort is CL1. Average indicates moderate appearance defects, form and position parameters are close to the specification limits, or comfort is CL2. Unqualified indicates severe appearance defects, form and position parameters exceed the specification limits, or comfort is CL3 / CL4.

[0041] like Figure 2 As shown, a second aspect of the present invention provides a comprehensive evaluation system for the status of rescue and evacuation channels on high-speed railway bridges, used to implement the method of the first aspect, comprising: The appearance and shape parameter measurement unit (101) is used to measure the appearance and shape parameters of evacuation passages based on UAV inspection and obtain the appearance and shape parameter measurement results. The pedestrian comfort evaluation unit (102) is used to evaluate the pedestrian comfort of evacuation routes based on acceleration tests and obtain pedestrian comfort evaluation results. The comprehensive evaluation unit (103) is used to conduct a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation passage based on the appearance and shape parameter measurement results and the pedestrian comfort evaluation results.

[0042] A third aspect of the present invention provides a comprehensive evaluation device for the status of rescue and evacuation channels on high-speed railway bridges, used to implement the method of the first aspect, comprising: The system includes a drone inspection module, an acceleration monitoring module, a data processing module, and a comprehensive evaluation module. The outputs of the drone inspection module and the acceleration monitoring module are connected to the input of the data processing module, and the output of the data processing module is connected to the input of the comprehensive evaluation module. The UAV inspection module includes a UAV body, an aerial camera, a positioning module, and a flight path planning unit. The flight path planning unit plans inspection routes that meet parameter requirements. The positioning module enables precise positioning of the UAV. The aerial camera collects inspection image data of evacuation routes. The UAV body completes the flight inspection according to the planned route. The aerial camera is a high-definition industrial camera with a resolution of at least 20 megapixels, and the positioning module uses GPS + BeiDou dual-mode positioning with a positioning accuracy of ≤1cm. The acceleration monitoring module includes a lateral acceleration sensor, a vertical acceleration sensor, a data acquisition unit, and a power supply unit. The lateral and vertical acceleration sensors are deployed at preset measuring points in the evacuation route to collect lateral and vertical acceleration response data under pedestrian influence. The data acquisition unit receives and stores the data collected by the acceleration sensors. The measurement accuracy of the lateral and vertical acceleration sensors is ±0.001 m / s², and the frequency response range is 0.1~100 Hz. The sampling frequency of the data acquisition unit is adjustable, with a maximum sampling frequency of not less than 100 Hz. The power supply unit uses a rechargeable lithium battery with a battery life of not less than 8 hours. The data processing module includes an image processing unit, a model building unit, an acceleration analysis unit, and a data comparison unit. The image processing unit performs image enhancement preprocessing on the inspection images. The model building unit constructs a 3D model of the evacuation route and measures its geometric parameters. The acceleration analysis unit extracts the maximum peak acceleration and performs comfort grading. The data comparison unit compares the current measurement data with historical data to analyze trends. The data processing module uses an industrial-grade server equipped with a multi-core processor and a high-performance graphics card, supporting large-scale image data processing and 3D model construction. The comprehensive evaluation module includes an indicator system construction unit, an evaluation result generation unit, and a report output unit. The indicator system construction unit is used to construct a comprehensive evaluation indicator system integrating appearance, shape and position parameters, and comfort. The evaluation result generation unit is used to complete the overall status evaluation of the evacuation passage based on the indicator system. The report output unit is used to generate and output a comprehensive evaluation report. The comprehensive evaluation module has a built-in evaluation algorithm, supports custom settings of indicator weights, can generate comprehensive evaluation reports with graphics and text, and supports output in multiple formats such as PDF and Excel.

[0043] Application principle: I. Status Assessment of Evacuation Routes Based on Integrated UAV Inspection According to the "Rules for Repairing High-Speed ​​Railway Bridges and Tunnels," when a bridge rescue and evacuation passage is located on the side with a ground-level maintenance passage, the clear width between the bridge pier and the evacuation passage should be no less than 3.0m. The evacuation passage should be independent of the beam structure; the top platform should preferably be located at the bridge pier, and the relative height difference between it and the top surface of the bridge deck work passage should not exceed 8cm. The gap between the top surface of the platform and the bridge deck shield should not be greater than 10cm or less than 5cm.

[0044] Drone inspections offer significant flexibility. Current routine bridge inspections already include drone inspections of the main structures such as piers and beams. At this stage, only specific flight points and shooting angles need to be added to the inspection flight plan for evacuation passage platforms and adjacent shielding areas. Drones can hover stably directly above the platform to take overhead photos, accurately measuring the height from the platform surface to a reference point below; they can also fly to the side of the platform, positioning their lenses directly at the gap between the platform top and the shielding to obtain clear vertical images. There is no need to organize separate operations for specific inspections; related inspection tasks can be completed simultaneously during routine inspection flights. Drone operations at individual passage inspection points add virtually no extra time cost. All captured images and measurement data are archived synchronously with the overall bridge inspection data. This not only provides the results of the current inspection but also allows for timely detection of subtle structural changes (such as gradual widening of gaps, platform settlement leading to changes in elevation) by comparing historical data (e.g., images and dimensional parameters of the platform-shield gap over the years). This continuous observation mechanism is of great value in assessing the structural health of safety passages and helps to initiate maintenance measures in a timely manner before potential risks escalate. In summary, drone detection technology has three advantages in safety monitoring of rescue and evacuation routes: first, it avoids the risks of manual high-altitude operations and improves safety; second, it is deeply integrated with conventional inspection processes to achieve efficient operation; and third, it ensures the accuracy and traceability of detection results through high-precision image acquisition and data archiving and comparison.

[0045] like Figure 3 The diagram shown illustrates the drone inspection process.

[0046] Step 1: Route Planning Flight route planning balances efficiency and coverage. The flight altitude is typically set at 1.5 times the height of the rescue passage (e.g., 30 meters for a 20-meter height), with a flight speed not exceeding 8 m / s. The overlap between the flight path and the lateral flight path should be no less than 80% and 70%, respectively. Considering the structural characteristics of the rescue passage, a combination of circumferential and intersecting flight paths is used: circumferential flights provide layered coverage of the passage's sides and top, while intersecting flight paths supplement orthophotos; the area connecting the passage and the bridge deck requires manual drone operation for close-up photography. Data collection should avoid periods of strong sunlight (such as midday) and inclement weather, prioritizing operations during the morning or afternoon when lighting is even.

[0047] Step 2: Control Point Deployment The control points on the bridge deck, underpass, and ground must be evenly distributed and extend 50 meters beyond both ends of the bridge. The coordinate measurement error of the control points must be controlled within ≤2cm for horizontal plane and ≤3cm for vertical plane. During data acquisition, image quality must be checked in real time to eliminate blurry, overexposed, or contaminated images, ensuring the reliability of the original data.

[0048] Step 3: 3D Model Construction Model construction consists of five major steps: data processing, aerial triangulation, point cloud generation, mesh optimization, and texture mapping.

[0049] 1) First, use Context Capture or Pix4Dmapper to import the image and control point data, and perform multi-view joint adjustment. The plane error of the control points should be ≤3cm and the elevation error should be ≤5cm.

[0050] 2) Then, a point cloud is generated using a dense matching algorithm, with a density of no less than 200 points / square meter. Key parts such as bridge piers and cables are densified to 500 points / square meter, while dynamic noise such as vegetation and vehicles is filtered out.

[0051] 3) The construction of the triangular mesh should retain the angular features of the bridge, use a non-uniform mesh (TIN), and manually repair the holes.

[0052] 4) Texture Mapping. The software automatically selects the best viewing angle image for texture mapping. For reflective surfaces (such as metal railings), HDR compositing or manual adjustments can be enabled. The final model needs to be lightweighted, output in blocks according to bridge spans in OBJ, FBX, and other formats, and support loading 3D tiles on the web. During accuracy verification, the total station measured coordinates and model coordinates need to be compared, with the horizontal and vertical errors controlled within ≤5cm and ≤8cm, respectively.

[0053] Step 4: Data Measurement and Verification Using drones to capture image data of the rescue passage, and combined with image enhancement algorithms, the feasibility of the method was verified by measuring two parameters: the height difference between the top platform of the rescue evacuation passage and the bridge deck operation passage, and the gap between the top surface of the platform and the bridge deck cover.

[0054] (1) Measurement of relative elevation difference, such as Figure 4 As shown.

[0055] Select the corresponding points of the top platform and the bridge deck operation passage in the model and measure the vertical distance.

[0056] pass Figure 4 Analysis shows that the height difference between the top platform and the bridge deck working passage has a significant grayscale difference compared to the concrete plane. Therefore, image enhancement techniques can be used to improve image brightness and contrast, highlighting the location of the height difference and improving the accuracy of related height difference measurements. Figure 5 As shown, the right image is the enhanced image. It can be seen that the position of the relative height difference is easily identified in the enhanced image, and the boundary of the height difference is also more obvious. The measurements were taken at three different positions, and the values ​​were 3.2cm, 3.1cm, and 3.3cm. The average value of the relative height difference measurement results was taken as 3.2cm.

[0057] The effectiveness of the method of the present invention was verified by measuring with a tape measure on site.

[0058] (2) The gap width was measured by quickly locating the gap position through image enhancement processing, and the average value of three measurements at different positions was taken to obtain a gap width of 4.97. The effectiveness of the method of the present invention was verified by measuring it on site with a tape measure.

[0059] II. Evaluation Method for Normal Usability of Evacuation Routes Based on Acceleration Testing Pedestrian comfort was evaluated according to German standards. Pedestrian comfort analysis is a reasonable assessment combining psychology and structural dynamics, reflecting whether structural vibrations will cause panic effects on pedestrians. Under normal use conditions, by measuring and comparing the vibration acceleration of evacuation routes with different structural forms under pedestrian traffic, the maximum peak acceleration responses were extracted for comparison. It was found that the lateral acceleration response of the sloping evacuation route was significantly more pronounced than that of the zigzag route.

[0060] The acceleration results for a typical high-speed railway rescue passage with a height of 11m are as follows: Figure 8 As shown, the maximum lateral vibration acceleration of the slope-type rescue passage is 0.077 m / s². 2Located at the end of an 11.0m high rest platform. The lateral acceleration response of the downhill rescue passage is 51% greater than that of the zigzag rescue passage. The overall lateral acceleration response of the zigzag rescue passage changes less with height, while the lateral acceleration response of the downhill rescue passage changes more significantly with height; the greater the height, the more intense the vibration. Comparing the vertical vibration accelerations of the two, it was found that the vertical vibration acceleration of the zigzag rescue passage is greater than that of the downhill one. The maximum vertical acceleration of the zigzag rescue passage is 0.238m / s². 2 The maximum vertical and lateral vibrations of the slope-type rescue passage are located at the top rest platform (11.0m), at a height of 6.5m.

[0061] Depend on Figure 9 It can be seen that the vibration acceleration response of the 15m high slope rescue passage shows the same trend as that of the 11m high slope rescue passage, both showing that the lateral acceleration is the largest at the rest platform at the top, which is 0.112m / s². 2 The vertical acceleration of the structure is less affected by height. The maximum vertical acceleration of the 15.0m detour rescue passage is 0.215m / s². 2 The vertical vibration acceleration is greater at the turning platform of the rescue passage. When the height is the same, the lateral vibration of the slope-type vibration is more intense than that of the deflection-type vibration, and the vertical vibration of the deflection-type vibration is stronger than that of the slope-type vibration.

[0062] like Figure 10 As shown, the maximum lateral vibration acceleration of the 20.0m downhill rescue passage is 0.143 m / s². 2 It is located at the end of a rest platform 20.0m high; the maximum vertical vibration acceleration is 0.293m / s². 2 It is located at the end of the rest platform, which is 20.0m high. The maximum lateral and vertical acceleration of the turning rescue passage occurs at the 10.0m turning rest platform, and the vibration is 38.4% greater than that of the slope-type rescue passage.

[0063] When the pedestrian density is 1 person / m 2 When the rescue passage is 11m high, the lateral acceleration response caused by pedestrian load is less than 0.1m / s² for all different structural forms. 2 It meets the requirements of CL1 level (best comfort). However, at heights of 15m and 20m, the maximum lateral acceleration of the downhill rescue passage is between 0.1 and 0.3 m / s². 2 Between these levels, the comfort level is CL2, which may cause some panic among pedestrians. In emergency situations, pedestrian density may be higher than 1 person / m². 2Larger pedestrian loads intensify structural vibrations, exacerbating the panic effect and causing even greater structural vibrations, potentially leading to collapse. Rescue passages employing different structural designs exhibit vertical acceleration responses of less than 0.5 m / s² under pedestrian loads. 2 It meets the requirements of CL1 level (best comfort). Regardless of the height H in meters, the vertical acceleration response of the deflecting evacuation passage is significantly greater than that of the slope-type passage. The vertical acceleration of the deflecting passage is 26.5% to 77% greater than that of the slope-type passage, which is basically the same as the swaying situation of the evacuation passage reported by the engineering department.

[0064] III. Rapid Screening Technology Based on Natural Frequency The natural frequency of a structure is the natural frequency of its free vibration under no external force. Its value is determined by the structure's mass distribution, stiffness characteristics, and boundary conditions. As a core parameter of structural dynamic characteristics, the natural frequency is not only an important basis for verifying structural safety during the design phase, but also a key indicator for assessing structural health, detecting structural damage, and predicting remaining life during the operational phase.

[0065] The evolution of natural frequencies can sensitively detect structural stiffness degradation (such as concrete cracking and steel corrosion), changes in boundary conditions (such as support failure and foundation scour), and environmental disturbances (such as temperature and wind load). Currently, structural natural frequency detection is widely used in bridge structural engineering to determine the stiffness of structures.

[0066] The natural frequency testing method used for this evacuation passage is the same as that used for the bridge structure: the natural excitation method. The natural excitation method identifies the natural frequency by measuring the structure's response to environmental excitation; this method is simple to operate and inexpensive.

[0067] The diagram shows the relationship between the first-order natural frequency of the lateral section and the height of the slope-type evacuation passage, as well as a summary diagram of the first-order natural frequencies of the lateral section.

[0068] The data shows that the first-order natural frequency in the transverse direction is mainly related to the column height and the number of columns. With the same number of columns, the first-order natural frequency in the transverse direction is directly proportional to the reciprocal of the square of the column height. Based on this, the linear fitting formulas are shown in equations (1)-(4) below: (1) One column: (1); (2) Two columns: (2); (3) 3 columns: (3); (4) 4 pillars: (4); In the formula, It is the natural frequency; This refers to the height of the column.

[0069] Based on the above formula, the natural frequency of the sloping evacuation channel can be quickly calculated from the column height, as shown in Table 1, which illustrates the lateral natural frequency characteristics of the deflected rescue evacuation channel.

[0070] Table 1

[0071] For the deflecting rescue passage, the first-order natural vibration mode in the lateral direction is the horizontal sway of the upper half of the staircase. The lowest height of the deflecting evacuation passage is 11m, and its theoretical calculated frequency is 2.27Hz; the highest height is 20m, and its theoretical calculated frequency is the lowest, with a value of 1.03Hz. From the data, it can be seen that the first-order natural vibration frequency in the lateral direction is mainly related to the height of the columns, the number of columns, and the number of steps. Under the same number of columns and steps, the first-order natural vibration frequency in the lateral direction is proportional to the reciprocal of the square of the height of the columns. Based on this, the linear fitting formula is as follows (5)-(7): (1) 4 pillars: (5); (2) 5 pillars - 3 steps on the ground floor: (6); (3) 5 pillars - 4 steps on the ground floor: (7); In the formula, It is the natural frequency; This refers to the height of the column.

[0072] Based on the above formula, the natural frequency of the deflecting evacuation passage can be quickly calculated from the height of the column.

[0073] Based on the vibration mode characteristics of the slope-type and deflection-type evacuation channels, and according to the characteristics of each structure, the locations of the measuring points were determined.

[0074] The natural frequency test of the evacuation passage includes horizontal and vertical measuring points, with the measuring points arranged at the mid-span and the top of the stairway.

[0075] Based on the calculated natural frequency, the sampling frequency for the natural frequency test of the evacuation passage was selected as 50Hz, and the Hanning window was selected for the time window during spectral analysis.

[0076] Experimental studies were conducted on the rescue and evacuation passages of several high-speed railway bridges of the same height. The height of the nine bridge rescue and evacuation passages was 12.5m, and all were designed according to the drawings. Evacuation passages 1-4 exhibited varying degrees of swaying depending on the site conditions; evacuation passage 5 was rigidly supported and connected to the box girder on site; evacuation passages 6-9 did not exhibit swaying; and evacuation passages 10-12 were newly designed pile foundation evacuation passages.

[0077] Typical work site 1: At kilometer marker K1239+350 (Suzhou North - Kunshan South) on the Beijing-Shanghai High-Speed ​​Railway, there is a 12.5m high evacuation passageway on the uphill side (12.5m). The evacuation passageway is noticeably swaying.

[0078] Typical work site 5: The evacuation passage at K23+436 on the southbound side of the Shanghai-Hangzhou High-Speed ​​Railway, a 12.6m long, was experiencing significant swaying and was subsequently reinforced on-site by the Hangzhou Railway Maintenance Section. (Evacuation passage reinforced after significant swaying).

[0079] Typical work site 7: The evacuation route along the downhill slope at K802+663 on the Datong-Xi'an High-Speed ​​Railway is normal and 12.55m high. The evacuation route is in normal use and there is no obvious shaking.

[0080] Typical work site 11: The newly constructed evacuation passage for the Shenyang-Baishan High-Speed ​​Railway is 12.4 meters high and uses a pile foundation design, resulting in no significant swaying. The newly designed sloping evacuation passage (pile foundation) is an example of this.

[0081] like Figure 11 As shown in the test results, for bridge evacuation passages that sway, the ratio of the measured natural frequency to the calculated natural frequency is 0.94~1.04; for bridge evacuation passages that do not sway, the ratio is 1.12~1.18. The natural frequency of the newly designed evacuation passages using pile foundations is significantly higher than that of the original evacuation passages. The relative relationship of the transverse natural frequencies of the structure can better reflect the transverse stiffness of the evacuation passages.

[0082] Experimental studies were conducted on evacuation passages of 10 turn-around bridges of different heights. The test results are shown in Table 2, which is a lateral frequency analysis of the turn-around evacuation passages. The heights of the 10 evacuation passages range from 11.0m to 20m, and all are designed according to the plan.

[0083] Table 2

[0084] Analysis of the above data shows that for bridge evacuation passages that are swaying, the ratio of their measured natural frequency to their calculated natural frequency is 0.98 to 1.04; for bridge evacuation passages that are not swaying, the ratio is 1.04 to 1.38. The transverse natural frequency of the structure can effectively reflect the operational status of the evacuation passage.

[0085] IV. Research on Basic Testing and Evaluation Technology for Rescue and Evacuation Routes 1. Basic Principles of the Mechanical Impedance Method The testing principle of the mechanical impedance method is to obtain the excitation force signal and the pile top velocity response signal by applying steady-state or transient excitation at the pile top, and obtain important parameters such as pile top velocity admittance and dynamic stiffness through simple analysis.

[0086] Here, "impedance" borrows the concept from electricity and is defined as the input excitation and output response of a fixed structure system, as shown in equation (8): (8); In the formula, Indicates the input stimulus of the system. It represents the system output velocity response (or displacement or acceleration response, etc.), and admittance is the reciprocal of impedance.

[0087] Assuming a vertical steady-state frequency sweep excitation is applied to a pile with a complete shaft and relatively uniform cross-section, at lower frequencies, the pile can be considered to move primarily in an approximate rigid body manner, and the first-order resonant frequency will appear first. As the frequency gradually increases, the pile undergoes longitudinal tensile and compressive deformation, resulting in higher-order resonant frequencies. If the transient mechanical impedance method is used, all resonant frequencies can be excited at once.

[0088] To simplify calculations and facilitate qualitative analysis, the pile body is usually assumed to be a single-degree-of-freedom system. When the excitation frequency is low, the differential equation of motion of the system can be expressed as shown in equation (9): (9) Assume that the excitation and response can be expressed as equation (10): (10) Substituting equation (10) into equation (9), and according to the definition of admittance, we can obtain the velocity admittance as equation (11): (11) In the formula, For frequency ratio, The damping ratio is denoted as .

[0089] The velocity admittance curve of a pile foundation objectively reflects the dynamic characteristics of the pile-soil system, and can be used to evaluate the integrity of the pile body and estimate the bearing capacity of the pile foundation. Important descriptive parameters in this curve include frequency deviation, geometric mean of the test admittance, and dynamic stiffness. The dynamic stiffness is defined by equation (12): (12) That is, the reciprocal of the slope of the low-frequency segment of the velocity admittance curve. In practical engineering, since it is difficult to accurately determine the tangent at the origin, the frequency f can be taken as a representative low-frequency value when calculating the actual dynamic stiffness, and correspondingly, K... d This represents the dynamic stiffness at a specific frequency. To reduce calculation errors, the average dynamic stiffness over a certain low-frequency range can also be used.

[0090] The dynamic stiffness calculated by the mechanical impedance method should be between the maximum and minimum dynamic stiffness, i.e., equation (13): ; Or equivalently expressed as: (13); in, The measured dynamic stiffness of the pile foundation (calculated by the mechanical impedance method through the low-frequency band of the velocity admittance curve); The minimum dynamic stiffness of the foundation when the pile bottom is supported on an ideal infinitely elastic foundation. The dynamic stiffness (maximum dynamic stiffness) of the foundation when the pile bottom is supported on an ideal infinitely rigid foundation. The dynamic stiffness of an infinitely long pile embedded in the soil; , These are characteristic parameters related to the dynamic properties of foundation soil (such as the soil stiffness coefficient and damping coefficient, and their derivation parameters). Among them: (14); In the formula, denoted as the damping coefficient of the soil.

[0091] Dynamic stiffness static stiffness They are related in some way, such as Figure 12 As shown, the slopes of the two curves represent dynamic stiffness and static stiffness, respectively. When the frequency of the dynamic load acting on the pile approaches 0, the dynamic stiffness value approaches the static stiffness, i.e. → The static stiffness can be obtained from the slope of the initial portion of the load-settlement curve obtained from static load tests. Since the frequency of dynamic loads is always greater than 0, the dynamic stiffness is always greater than the static stiffness. Typically, the dynamic-to-static contrast coefficient η is defined as... / Using this coefficient, the bearing capacity can be indirectly estimated through the mechanical impedance method, as shown in equation (15): (15); In the formula, This represents the allowable settlement of a single pile.

[0092] From the theoretical derivation of the mechanical impedance method, the column is mainly simplified as a mass-spring system undergoing translational motion under dynamic load. Based on its simplified analytical calculation model and theoretical calculation process, the stress state of the enlarged foundation is closer to the theoretical calculation model. Therefore, theoretically, the mechanical impedance method can be used to evaluate the overall stiffness and bearing capacity of the enlarged foundation. Since evacuation routes differ from bridge structures themselves—bridge piers have added weight from piers and beams above the foundation—this may affect the measured values ​​of dynamic stiffness. However, the load above the columns of evacuation routes is simple and fixed, with less impact, making the mechanical impedance method more suitable for assessing the foundation's bearing capacity.

[0093] Field test verification analysis To further verify the relationship between the dynamic stiffness and bearing capacity of evacuation channels, on-site verification of the dynamic stiffness of rescue and evacuation channels on high-speed railway bridges was carried out.

[0094] First, the enlarged foundation of the column foundation was excavated. By placing the excitation device and vibration pickup on the side of the foundation, the velocity signal under excitation was measured, and the velocity admittance curve was derived. The actual dynamic stiffness test results were obtained using the low-frequency characteristics of the velocity admittance curve. Figure 13 As shown in Table 3, the ratio of dynamic stiffness test results for each column evacuation passage is 1:1.32:1.69, which basically corresponds to the relationship of 1:1.34:1.74 between the theoretical calculated bearing capacity and the ratio of dynamic stiffness test results for each column evacuation passage.

[0095] Table 3

[0096] Based on the analysis of the measured dynamic stiffness results and the indoor model analysis, it is reasonable to use dynamic stiffness theory to analyze the stiffness state of the foundation. In particular, the relative qualitative bearing capacity of the columns in the same evacuation passage or the columns at the same height during evacuation is more obvious. When the implementation conditions are met and more test samples are obtained, directly obtaining the dynamic stiffness and its estimated bearing capacity can quantitatively assess the actual bearing capacity of the foundation.

[0097] Application Examples: The system used in this embodiment includes a UAV inspection module, an acceleration monitoring module, a data processing module, and a comprehensive evaluation module. The specific configurations of each module are as follows: 1. Drone Inspection Module: The drone body uses DJI Matrice M300RTK, the aerial photography camera uses Zenmuse P1 full-frame aerial survey camera with 45 million pixels, the positioning module is GPS + Beidou dual-mode positioning with positioning accuracy of ±0.5cm, and the flight path planning unit is equipped with DJI Terra flight path planning software. 2. Acceleration monitoring module: The horizontal and vertical acceleration sensors adopt the BK4371 type acceleration sensor, with a measurement accuracy of ±0.001m / s² and a frequency response range of 0.1~100Hz. The data acquisition instrument adopts the INV3062C type dynamic signal acquisition instrument with a maximum sampling frequency of 100Hz. The power supply unit is a 24V rechargeable lithium battery with a battery life of 10 hours. 3. Data processing module: It adopts an industrial-grade server, configured with an Intel Xeon Gold 6330 processor, 128G memory, and NVIDIA RTX A6000 graphics card, and is equipped with ContextCapture 2021, Pix4D mapper 4.9, and Matlab R2022b software, which are used for 3D model construction, image processing, and acceleration signal analysis, respectively. 4. Comprehensive Evaluation Module: Equipped with self-developed comprehensive evaluation software for the status of high-speed railway bridge rescue and evacuation channels, supporting customizable indicator weights, automatic generation of evaluation results, and multi-format report output.

[0098] The comprehensive evaluation method for the status of high-speed railway bridge rescue and evacuation channels in this embodiment includes the following specific steps: Step S1: Measurement of the appearance and shape parameters of evacuation routes by integrating drone inspection The core of this step is to integrate the inspection path of the main bridge structure into the appearance inspection of the 12.5m high slope-type evacuation passage. By collecting image data through drone inspection, a three-dimensional model is constructed, and the appearance defects, shape and position parameters are measured and trend analysis is completed. Specifically, it is divided into six sub-steps: route planning, control point layout, image acquisition, three-dimensional model construction, parameter measurement, and data comparison.

[0099] S11, Route Planning Based on the route planning parameters of this invention, and considering the evacuation passage's height of 12.5m, the UAV flight altitude is set at 18.75m (12.5m × 1.5m), flight speed at 6m / s (≤8m / s), directional overlap at 85% (≥80%), and lateral overlap at 75% (≥70%). A combination of circling flight and cross-route flight is adopted. The circling flight is divided into three layers, covering the side areas of the bottom (0~4m), middle (4~8m), and top (8~12.5m) of the evacuation passage, respectively. Five cross-route flights are set, covering the top platform of the evacuation passage and the area connecting with the bridge deck. For the connection between the evacuation passage and the bridge deck operation passage, the UAV is manually operated to take close-up photos, with the shooting distance controlled within 3m. The inspection operation is carried out from 9:00 to 11:00 am on weekday mornings, when the lighting is uniform, there is no strong direct sunlight, and there is no severe weather such as strong winds or rain.

[0100] S12. Control Point Layout Twenty control points were evenly distributed across the bridge deck, the main structure of the evacuation passage, and the ground where the evacuation passage is located. Eight control points were placed on the bridge deck, six on the evacuation passage, and six on the ground. All control points extended 50 meters beyond both ends of the bridge. The coordinates of the control points were measured using a total station. The measurement was repeated three times, and the average value was taken as the final coordinates of the control points. The horizontal measurement error of the control points was controlled within 1.5 cm (≤2 cm), and the vertical measurement error was controlled within 2.2 cm (≤3 cm), both of which meet the layout requirements of this invention.

[0101] S13, Image Acquisition Operators import the planned flight path into the UAV through the flight path planning unit, start the UAV inspection module, and the UAV flies automatically according to the preset flight path. The aerial camera simultaneously collects image data of the evacuation route, and the positioning module records the shooting coordinates of each image in real time. During the image acquisition process, the data acquisition personnel check the image quality in real time through the UAV ground station. A total of 862 images were collected, and 12 images that were blurry, overexposed, or smudged were excluded. Finally, 850 images were valid, with an effectiveness rate of 98.6%.

[0102] S14, 3D Model Construction The effective image data and control point coordinate data are imported into the model building unit of the data processing module. The 3D model is then built using ContextCapture2021 software, which includes five main steps: data processing, aerial triangulation, point cloud generation, mesh optimization, and texture mapping. 1. Data processing: Perform preprocessing on image data, such as distortion correction and brightness equalization, to ensure the consistency of image data; 2. Aerial triangulation solution: Import control point coordinate data and perform multi-view joint adjustment. After adjustment, the plane error of the control points is 2.8cm (≤3cm) and the elevation error is 4.5cm (≤5cm), which meets the accuracy requirements. 3. Point cloud generation: Point clouds are generated through a dense matching algorithm, with a point cloud density of 250 points / square meter (≥200 points / square meter). Key parts such as evacuation channel pillars and top platforms are densified to 550 points / square meter (≥500 points / square meter). At the same time, dynamic noise such as vegetation and passing vehicles are filtered out through software algorithms to retain the point cloud data of the main structure of the evacuation channel. 4. Mesh optimization: A non-uniform triangular mesh (TIN) was used to construct the mesh model, preserving the structural features of the evacuation channels such as edges and steps. Small holes appearing in the model were manually repaired, with a total of 18 holes repaired. 5. Texture Mapping: The software automatically selects the image from the best viewpoint for texture mapping. For reflective surfaces such as metal railings in evacuation routes, HDR compositing technology is used to optimize the texture and avoid texture blurring caused by reflection. After texture mapping is completed, the 3D model is lightweighted and output in OBJ format by bridge span, which supports loading on the Web client's 3DTiles. 6. Accuracy Verification: The coordinates of 10 feature points of the evacuation route were measured using a total station. The measured coordinates were compared with the coordinates of the corresponding feature points in the 3D model. The results showed that the maximum plane error was 4.2cm (≤5cm) and the maximum elevation error was 7.5cm (≤8cm). The accuracy of the 3D model met the requirements of this invention and can be used for subsequent geometric parameter measurement.

[0103] S15, Parameter Measurement Based on the completed 3D model, the image processing unit of the data processing module is invoked. A histogram equalization image enhancement algorithm is used to improve the brightness and contrast of the image, highlighting the boundary positions of relative height differences and gap widths. Subsequently, visual defects are identified, and geometric parameters are measured, specifically: 1. Identification of external defects: Using 3D models and high-definition images, external defects of the evacuation passage were identified. It was found that there were slight surface cracks on the two bottom columns of the evacuation passage, with a crack width of 0.1~0.2mm. There was a small amount of concrete spalling at the edge of the top platform. There were no obvious damages or serious external defects such as exposed rebar. At the same time, the tilt of the evacuation passage columns was analyzed by using point cloud data from the 3D model. The measurement results showed that the tilt of all columns was ≤0.1%, which meets the design specifications for high-speed railway bridge rescue evacuation passages. 2. Relative Height Difference Measurement: Three corresponding measurement points (left, middle, and right sides of the platform) between the top platform of the evacuation passage and the bridge deck operation passage were selected in the 3D model. The vertical distances of the three points were measured respectively, and the results were 3.1cm, 3.2cm, and 3.3cm. The average value of 3.2cm was taken as the final relative height difference measurement result. The relative height difference was measured on-site using a 5m steel tape measure, and the measured result was 3.1cm. The error between the measured result and the UAV measurement result was only 0.1cm, verifying the accuracy of the measurement result. According to the "Rules for Repair of High-Speed ​​Railway Bridge and Tunnel Structures", the relative height difference between the top platform of the evacuation passage and the top surface of the bridge deck operation passage should not be greater than 8cm. The measured result of 3.2cm is far less than the limit of the specification and meets the requirements. 3. Gap Width Measurement: Three measurement points (left, middle, and right) between the platform top surface and the bridge deck shield were selected in the 3D model. The gap width at each of the three points was measured, and the results were 4.9cm, 5.0cm, and 5.0cm respectively. The average value of 4.97cm was taken as the final gap width measurement result. On-site measurement was conducted using a steel tape measure, and the actual measurement result was 5.0cm. The error between the measurement result and the UAV measurement result was only 0.03cm, indicating that the measurement result was accurate. According to the "Repair Rules for High-Speed ​​Railway Bridge and Tunnel Structures", the gap between the platform top surface and the bridge deck shield should be within the range of 5-10cm. The measurement result of 4.97cm is close to the lower limit of the specification and does not exceed the limit, thus meeting the requirements.

[0104] S16, Data Comparison The relative height difference (3.2cm), gap width (4.97cm), column tilt (≤0.1%), and appearance defects measured in this study were compared with the historical inspection data of the evacuation passage over the previous two years. The results showed that the relative height difference increased by 0.2cm compared to last year, the gap width increased by 0.17cm compared to last year, the column tilt remained unchanged, and the appearance defects were newly added minor defects. Analysis of the trend shows that the shape and position parameters of the evacuation passage are changing slowly without any sudden changes. The newly added minor appearance defects have not affected the structural safety, but the parameter changes and defect development need to be continuously monitored.

[0105] Step S2: Pedestrian comfort evaluation of evacuation routes based on acceleration test The core of this step is to deploy acceleration sensors on the 12.5m high sloping evacuation passage to collect lateral and vertical acceleration response data under the action of pedestrians, and complete the comfort level evaluation. Specifically, it is divided into five sub-steps: measurement point layout, sensor debugging, acceleration data acquisition, acceleration signal analysis, and comfort evaluation.

[0106] S21. Measurement point layout According to the measurement point layout principle of this invention, and combined with the structural characteristics of the sloping evacuation channel, five measurement points are arranged along the height direction at the mid-span and top of the stairway of the evacuation channel, at rest platforms at heights of 2.5m, 5.0m, 7.5m, 10.0m, and 12.5m respectively. Each measurement point is equipped with one lateral acceleration sensor and one vertical acceleration sensor, for a total of 10 acceleration sensors. The sensors are fixed to the concrete structure surface of the evacuation channel with special clamps to ensure that the sensors are tightly fitted to the structure without loosening.

[0107] S22, Sensor Adjustment Connect the accelerometer to the data acquisition unit, start the power supply unit of the acceleration monitoring module, debug the sensor, set the sampling frequency of the data acquisition unit to 50Hz (which meets the requirement of not less than 50Hz in this invention), perform zero-point calibration and sensitivity calibration, and the calibration results show that the zero-point error of all sensors is ≤±0.001m / s², the sensitivity error is ≤±1%, the sensor is working normally, and acceleration data acquisition can be performed.

[0108] S23, Acceleration Data Acquisition To simulate a real pedestrian scenario, a pedestrian density of 1 person / m² (the pedestrian density in a normal use scenario) was set. Three testers walked back and forth on the evacuation route at a normal pace, continuously collecting lateral and vertical acceleration response data for 10 minutes. Simultaneously, to simulate pedestrian load conditions in an emergency, a pedestrian density of 2 people / m² was set, and six testers walked quickly on the evacuation route, continuously collecting acceleration data for 5 minutes. The data acquisition instrument received and stored the acceleration signals collected by all sensors in real time, collecting a total of 180,000 sets of raw acceleration data.

[0109] S24. Acceleration Signal Analysis The collected raw acceleration data was imported into the acceleration analysis unit of the data processing module. Matlab R2022b software was used to preprocess the acceleration signal, including denoising and filtering, to eliminate noise signals such as environmental interference and equipment vibration. Subsequently, the maximum peak acceleration of each measuring point under normal pedestrian density (1 person / m²) and emergency pedestrian density (2 people / m²) was extracted from the processed acceleration signal. The specific results are shown in Table 4, which shows the measurement results (m / s²) of the maximum peak acceleration of each measuring point in the 12.5m high downhill evacuation channel.

[0110] Table 4

[0111] As can be seen from Table 4, the peak lateral and vertical accelerations of the sloping evacuation passage increase with the increase of the measuring point height, with the maximum peak acceleration occurring at the top rest platform at a height of 12.5m. Meanwhile, the peak acceleration under emergency pedestrian density is about twice that under normal pedestrian density, indicating that the increase in pedestrian density will significantly aggravate the vibration response of the evacuation passage, which is consistent with the actual engineering situation.

[0112] S25, Comfort Evaluation Based on the German EN03 standard for pedestrian comfort evaluation adopted in this invention, the pedestrian comfort of this evacuation passage under normal pedestrian density and emergency pedestrian density is evaluated in a graded manner. The evaluation results are shown in Table 5, which shows the pedestrian comfort evaluation results of the 12.5m high downhill evacuation passage.

[0113] Table 5

[0114] As shown in Table 5, under normal pedestrian density (1 person / m²), the maximum lateral peak acceleration of the evacuation passage is 0.077 m / s² (<0.10 m / s²), and the maximum vertical peak acceleration is 0.210 m / s² (<0.50 m / s²), with a comfort level of CL1. Under emergency pedestrian density (2 people / m²), the maximum lateral peak acceleration is 0.154 m / s², which is slightly higher than 0.10 m / s², but the maximum vertical peak acceleration is 0.420 m / s² (<0.50 m / s²), and the overall comfort level is still CL1. The comfort evaluation results under both pedestrian densities are CL1, indicating that the dynamic response of the evacuation passage under pedestrian conditions meets the requirements for normal use, which is consistent with the actual on-site test result of "slight shaking, not affecting pedestrians".

[0115] Step S3: Comprehensive evaluation of evacuation route status The appearance and shape parameter measurement results of step S1 and the pedestrian comfort evaluation results of step S2 are imported into the comprehensive evaluation module to construct a comprehensive evaluation index system and complete the overall status evaluation of the 12.5m high slope-type evacuation passage. Specifically, it is divided into four sub-steps: index system construction, index weight setting, status evaluation, and report generation.

[0116] S31. Construction of the Indicator System A three-tiered comprehensive evaluation index system is constructed, integrating appearance defects, shape and position parameters, and comfort indicators. The first-level indicator is the overall condition of the evacuation passage; the second-level indicators are appearance defects, shape and position parameters, and pedestrian comfort; and the third-level indicators are specific evaluation factors, as follows: 1. Appearance defects (secondary indicators): Tertiary indicators include cracks, concrete spalling, damage, and column tilt; 2. Geometric parameters (secondary indicators): Tertiary indicators include relative elevation difference, gap width, and parameter variation trend; 3. Pedestrian comfort (secondary indicator): The tertiary indicators include the comfort level of normal pedestrian density and the comfort level of emergency pedestrian density.

[0117] S32, Indicator Weight Setting The weights of each indicator were determined using the Analytic Hierarchy Process (AHP). Combining the operational safety requirements of high-speed railway bridge rescue and evacuation channels with practical engineering experience, five experts in the field of high-speed railway bridge engineering were invited to score the weights, and the average value was taken as the final weight. The specific weight allocation is shown in Table 6, which illustrates the comprehensive evaluation index system and weights for the status of high-speed railway bridge rescue and evacuation channels.

[0118] Table 6

[0119] S33, Status Evaluation According to the evacuation route status level classification standard of the present invention, combined with the evaluation results and weights of each of the three levels of indicators, a weighted summation method is used to calculate the comprehensive evaluation score, with a full score of 100 points. The correspondence between status level and score is as follows: Excellent (90~100 points), Good (80~89 points), Average (70~79 points), and Unqualified (<70 points). The scoring criteria for each of the three levels of indicators and the specific scores of the evacuation route are shown in Table 4, which shows the scoring results of each of the three levels of indicators for a 12.5m high slope evacuation route.

[0120] Table 7

[0121] Calculate the overall evaluation score based on the weight and score of each indicator: 1. Appearance defects score = 80 × 0.40 + 80 × 0.20 + 100 × 0.30 + 100 × 0.10 = 88 points; 2. Geometric Parameter Score = 100 × 0.35 + 80 × 0.35 + 80 × 0.30 = 89 points; 3. Pedestrian comfort score = 100 × 0.50 + 100 × 0.50 = 100 points; 4. Overall score = 88 × 0.30 + 89 × 0.40 + 100 × 0.30 = 92 points.

[0122] The evacuation route received a comprehensive evaluation score of 92 points, which is considered excellent. The overall condition of the evacuation route is good, with no safety hazards. Only minor new cosmetic defects need to be treated, and the changing trends of the shape and position parameters should be continuously monitored.

[0123] S34, Report Generation The report output unit of the comprehensive evaluation module is invoked to generate a comprehensive status evaluation report for the 12.5m high slope-type high-speed railway bridge rescue and evacuation passage. The report includes five parts: project overview, UAV inspection results, acceleration test results, comprehensive evaluation results, and maintenance recommendations. It covers all measurement data, analysis charts, evaluation results, and targeted maintenance recommendations. The report supports output in both PDF and Excel formats and can be directly submitted to the high-speed railway engineering department as a scientific basis for the maintenance and repair of the evacuation passage.

[0124] The implementation results of this embodiment show that the comprehensive evaluation method and system for the status of high-speed railway bridge rescue and evacuation channels of the present invention can efficiently and accurately complete the identification of appearance defects, measurement of shape and position parameters, and evaluation of pedestrian comfort of evacuation channels, and realize a comprehensive and scientific evaluation of the overall status of evacuation channels. The evaluation results are highly consistent with the actual engineering situation, and provide an effective technical means for ensuring the operational safety of high-speed railway bridge rescue and evacuation channels.

[0125] It should be noted that the above embodiments are only evaluation examples of downhill evacuation channels. For zigzag evacuation channels, it is only necessary to adjust the UAV inspection route and the position of the acceleration sensor measuring points according to their structural characteristics. The remaining evaluation steps and parameter requirements are consistent with the present invention, and accurate comprehensive evaluation can also be achieved. At the same time, the method and system of the present invention can be applied to high-speed railway bridge rescue evacuation channels of different heights (such as 11m, 15m, 20m), and have wide applicability.

[0126] The present invention also provides a memory that stores a plurality of instructions for implementing the methods as described in the embodiments and application embodiments.

[0127] like Figure 14 As shown, the present invention also provides an electronic device, including a processor 301 and a memory 302 connected to the processor 301. The memory 302 stores a plurality of instructions, which can be loaded and executed by the processor to enable the processor to perform the methods as described in the embodiments and application embodiments.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges, characterized in that, include: S1, Based on UAV inspection, measure the appearance and position parameters of the evacuation passage to obtain the appearance and position parameter measurement results; S2, pedestrian comfort evaluation results are obtained by evaluating pedestrian comfort in evacuation routes based on acceleration tests; S3, Based on the appearance and shape parameter measurement results and the pedestrian comfort evaluation results, a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation channel is conducted; S1 includes: S11 integrates the inspection path of the main bridge structure into the visual inspection of evacuation passages and plans drone inspection routes for evacuation passages. S12, Set up control points and collect inspection image data; S13, Process the inspection image data to construct a three-dimensional model of the evacuation route; S14. Based on the three-dimensional model of the evacuation channel and combined with the image enhancement algorithm, measure the relative height difference between the top platform of the evacuation channel and the bridge deck operation channel, as well as the gap width between the top surface of the platform and the bridge deck shield. At the same time, identify the appearance defects of the evacuation channel and the tilt of the columns to form appearance and position parameter measurement data. S15, compare the appearance and shape parameter measurement data with historical inspection data, analyze the changing trend of structural parameters, and thus obtain the appearance and shape parameter measurement results.

2. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 1, characterized in that, S2 includes: S21. Based on the structural form of the evacuation passage, horizontal and vertical acceleration sensors are arranged at preset measuring points to collect horizontal and vertical acceleration response data at rest platforms at different heights of the evacuation passage under the action of pedestrians, and the maximum peak acceleration of each measuring point is extracted. S22, based on the pedestrian comfort evaluation standard of the German EN03 standard, classifies and evaluates the pedestrian comfort of evacuation routes, and judges whether the dynamic response of evacuation routes in pedestrian conditions meets the normal use requirements, thereby obtaining the pedestrian comfort evaluation results.

3. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 2, characterized in that, S3 includes: S31, a comprehensive evaluation index system is constructed based on the measurement results of the appearance and shape parameters and the evaluation results of pedestrian comfort; S32. Based on the comprehensive evaluation index system, evaluate the overall status of the high-speed railway bridge rescue and evacuation passage, generate a comprehensive evaluation report, and clarify the status level and hidden danger location of the evacuation passage.

4. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 3, characterized in that, The specific parameters for the UAV inspection route for the evacuation channel in S11 are as follows: the flight altitude is set to 1.5 times the height of the rescue channel, the flight speed does not exceed 8m / s, the directional overlap is not less than 80%, and the lateral overlap is not less than 70%; a combination of circling flight and cross-route mode is adopted, with circling flight covering the sides and top of the channel in layers, and cross-route supplementing orthophotos; the UAV is manually controlled to take close-up photos of the area where the channel connects to the bridge deck; the data collection time avoids strong light periods and inclement weather, and the operation is carried out in the morning or afternoon when the lighting is uniform; the requirements for the layout of control points in S12 are as follows: control points are evenly distributed on the bridge deck, channel, and ground, and extend to 50 meters beyond both ends of the bridge; the coordinate measurement error of the control points is controlled within the range of ≤2cm in plane and ≤3cm in elevation; During data acquisition, image quality is checked in real time to eliminate blurry, overexposed, or smudged images; S13 includes: S131, Data processing, including: importing image and control point data using Context Capture or Pix 4D mapper, performing multi-view joint adjustment, so that the control point plane error is ≤3cm and the elevation error is ≤5cm; S132, Point cloud generation, including: generating point clouds through a dense matching algorithm, with a point cloud density of not less than 200 points / square meter, and key parts such as bridge piers and cables being densified to 500 points / square meter, while filtering dynamic noise points such as vegetation and vehicles; S133, Mesh optimization, including: constructing a triangular mesh using a non-uniform mesh, preserving the angular features of the bridge, and manually repairing mesh holes; S134, Texture mapping, including: automatically selecting the best viewing angle image for texture mapping by software, and enabling HDR compositing or manual adjustment for reflective surfaces such as metal railings; S135, aerial triangulation solution, includes: lightweight processing of the 3D model, outputting the model in OBJ or FBX format by bridge span blocks, supporting 3D Tiles loading on the Web; comparing the total station measured coordinates with the model coordinates to verify the model accuracy, ensuring that the plane error is ≤5cm and the elevation error is ≤8cm. The relative height difference between the top platform of the evacuation passage and the bridge deck operation passage, as well as the gap width between the top surface of the platform and the bridge deck shield, as measured in S14, include: In the 3D model, corresponding measurement points are selected, and image enhancement algorithms are used to improve image brightness and contrast, highlighting the height difference and gap boundaries. The relative height difference and gap width were measured at least three times at different locations, and the average value was taken as the final measurement result. The accuracy of the measurement result was verified by on-site measurement.

5. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 4, characterized in that, The arrangement principle of the preset measuring points in S21 is as follows: the measuring points of the evacuation channels with slope and turn are arranged at the rest platform at the middle of the span and the top of the stairway, covering different height ranges of the evacuation channel from bottom to top; the sampling frequency of the accelerometer is not less than 50Hz, and the pedestrian density is ensured to match the actual use scenario during the collection process, simulating the pedestrian load state under normal pedestrian and emergency conditions.

6. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 5, characterized in that, The pedestrian comfort evaluation standard based on the German EN03 standard includes a graded evaluation of pedestrian comfort in evacuation routes, which includes: Comfort level CL1 is the best comfort level, with peak vertical acceleration <0.50m / s² and peak lateral acceleration <0.10m / s². The comfort level CL2 is a medium comfort level, with a vertical peak acceleration of 0.50~1.00m / s² and a lateral peak acceleration of 0.10~0.30m / s². The comfort level CL3 is the tolerable comfort level, with a vertical peak acceleration of 1.00~2.50 m / s² and a lateral peak acceleration of 0.30~0.80 m / s². Comfort level CL4 is an unacceptable comfort level, with peak vertical acceleration > 2.50 m / s² and peak lateral acceleration > 0.80 m / s². The determination of whether the dynamic response of the evacuation route in pedestrian condition meets the normal use requirements includes: when the comfort evaluation result of the evacuation route is CL3 or CL4, it is determined that its dynamic response does not meet the normal use requirements.

7. The comprehensive evaluation method for the status of rescue and evacuation channels on high-speed railway bridges according to claim 6, characterized in that, The comprehensive evaluation index system includes: Visual defects include cracks, damage, and concrete spalling; Geometric parameters, including relative height difference, gap width, column inclination and parameter variation trends; Comfort indicators, including: pedestrian comfort rating results; The evaluation of the overall status of the high-speed railway bridge rescue and evacuation passage based on the comprehensive evaluation index system, and the generation of a comprehensive evaluation report, includes: Based on the weights and evaluation criteria of each indicator, the overall condition of evacuation routes is divided into four levels: excellent, good, average, and unqualified. Excellent indicates no appearance defects, form and position parameters meet the specifications, and comfort is CL1. Good indicates minor appearance defects, form and position parameters are within the allowable range of the specifications, and comfort is CL1. Average indicates moderate appearance defects, form and position parameters are close to the specification limits, or comfort is CL2. Unqualified indicates severe appearance defects, form and position parameters exceed the specification limits, or comfort is CL3 / CL4.

8. A comprehensive evaluation system for the status of rescue and evacuation channels on high-speed railway bridges, used to implement the method described in any one of claims 1-7, characterized in that, include: The appearance and shape parameter measurement unit (101) is used to measure the appearance and shape parameters of evacuation passages based on UAV inspection and obtain the appearance and shape parameter measurement results. The pedestrian comfort evaluation unit (102) is used to evaluate the pedestrian comfort of evacuation routes based on acceleration tests and obtain pedestrian comfort evaluation results. The comprehensive evaluation unit (103) is used to conduct a comprehensive evaluation of the status of the high-speed railway bridge rescue and evacuation passage based on the appearance and shape parameter measurement results and the pedestrian comfort evaluation results.

9. A comprehensive evaluation device for the status of rescue and evacuation channels on high-speed railway bridges, used to implement the method described in any one of claims 1-7, characterized in that, include: The module includes a drone inspection module, an acceleration monitoring module, a data processing module, and a comprehensive evaluation module. The outputs of the UAV inspection module and the acceleration monitoring module are connected to the input of the data processing module, and the output of the data processing module is connected to the input of the comprehensive evaluation module. The UAV inspection module includes a UAV body, an aerial camera, a positioning module, and a flight path planning unit. The flight path planning unit plans inspection routes that meet parameter requirements. The positioning module enables precise positioning of the UAV. The aerial camera collects inspection image data of evacuation routes. The UAV body completes flight inspections according to the planned flight path. The aerial camera uses a high-definition industrial camera, and the positioning module uses GPS + BeiDou dual-mode positioning with a positioning accuracy of ≤1cm. The acceleration monitoring module includes a lateral acceleration sensor, a vertical acceleration sensor, a data acquisition unit, and a power supply unit. The lateral and vertical acceleration sensors are deployed at preset measuring points in the evacuation route to collect lateral and vertical acceleration response data under pedestrian influence. The data acquisition unit receives and stores the data collected by the acceleration sensors. The measurement accuracy of the lateral and vertical acceleration sensors is ±0.001 m / s², and the frequency response range is 0.1~100 Hz. The sampling frequency of the data acquisition unit is adjustable, with a maximum sampling frequency of not less than 100 Hz. The data processing module includes an image processing unit, a model building unit, an acceleration analysis unit, and a data comparison unit. The image processing unit performs image enhancement preprocessing on the inspection images. The model building unit constructs a 3D model of the evacuation route and measures its geometric parameters. The acceleration analysis unit extracts the maximum peak acceleration and performs comfort grading. The data comparison unit compares the current measurement data with historical data to analyze trends. The data processing module uses an industrial-grade server equipped with a multi-core processor and a high-performance graphics card, supporting large-scale image data processing and 3D model construction. The comprehensive evaluation module includes an indicator system construction unit, an evaluation result generation unit, and a report output unit. The indicator system construction unit is used to construct a comprehensive evaluation indicator system that integrates appearance, shape and position parameters, and comfort. The evaluation result generation unit is used to complete the overall status evaluation of the evacuation passage based on the indicator system. The report output unit is used to generate and output a comprehensive evaluation report. The comprehensive evaluation module has a built-in evaluation algorithm.

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