Early warning method for water disasters along railways in areas without hydrological data

Abstract

The invention belongs to the technical field of flood early warning, and provides a water disaster early warning method along a railway in a region without hydrological data, which comprises the following steps: S1, determining starting and ending positions of a disaster-prone section of the railway; s2, drawing a flood catchment area corresponding to the disaster-prone section of the railway; s3, the early warning water level of the drainage facility of the railway disaster-prone section is obtained, and the early warning flood flow is calculated; and S4, obtaining a rainstorm recurrence period to carry out early warning in advance. According to the method, the corresponding early warning rainfall capacity and the flood control recurrence period can be calculated according to the specific requirements of the disaster-prone section of the railway, so that the flood response capacity along the railway is greatly improved, the railway transportation safety and continuity are ensured, and meanwhile, an important basis is provided for relevant departments to formulate flood control strategies.

Description

Technical Field

[0001] The invention belongs to the technical field of flood early warning, and in particular relates to a flood early warning method along a railway line in an area without hydrological data. Background Art

[0002] As an important transportation infrastructure in my country, railways undertake a large number of tasks in transporting people and materials. It is estimated that by 2035, the national railway network will reach 200,000 kilometers, including 70,000 kilometers of high-speed railways. However, due to the frequent occurrence of natural disasters in my country, especially water disasters, the safe operation of railways faces severe challenges. Railway lines extend over long distances and the environment along the lines is complex. Once a water disaster occurs, it may paralyze railway facilities and even trigger the collapse of the system-level transportation network, causing major safety accidents.

[0003] At present, most areas along the railway lack real-time hydrological monitoring systems, which makes it difficult to effectively assess and warn of flood risks without direct flow test data. In addition, although flood warnings are important safety measures, compared with rainstorm warnings, the latter are easier to implement and operate because they are more direct and clear. Rainstorm warnings rely on rainfall forecasts provided by meteorological departments and can accurately predict the risk level of railway water damage in advance.

[0004] In view of this, it is particularly urgent to study and develop a method that can effectively predict and warn of railway water disaster risks. Summary of the invention

[0005] The present invention provides a method for early warning of flood disasters along railways in areas without hydrological data, aiming to infer the rainfall at a certain railway location and infer whether a flood may occur at that location. The present invention is implemented in this way: a method for early warning of water disasters along railway lines in areas without hydrological data comprises the following steps: S1. Determine the starting and ending locations of the disaster-prone sections of the railway; S2. Draw the flood catchment areas corresponding to the vulnerable railway sections; S3. Obtain the warning water level of drainage facilities in the disaster-prone sections of the railway and calculate the warning flood flow; S4. Obtain the rainstorm recurrence period for early warning.

[0006] Optionally, the step S1 includes: S1a. Conduct field surveys along the railway to detect and record flood signs in the railway and surrounding areas; S1b. Analyze field survey data and historical flood records to determine the start and end locations of vulnerable railway sections.

[0007] S1c. Combine field survey results with historical flood data to accurately measure and mark the geographic coordinates of the start and end locations of disaster-prone sections of the railway.

[0008] Optionally, step S2 includes: S2a. Obtain elevation information of disaster-prone sections of railways and their surrounding terrain; S2b. Draw a watershed map of the vulnerable railway section from the starting location to the end location.

[0009] Optionally, step S3 includes: S3a. Measure the drainage facilities in the affected railway section and draw a structural diagram of the drainage facilities; S3b. Calculate the water flow capacity according to the drainage facility structure diagram; S3c. Determine the upper limit of safe flood discharge level and warning flood flow of drainage facilities.

[0010] Optionally, the drainage facility of S3b is an open channel, and the calculation formula for the water flow capacity of the open channel is: in, is the water flow rate in cubic meters per second (m 3 / s); is the cross-sectional area of ​​the drainage ditch, in square meters (m 2 ); is Xiecai coefficient; is the water conservancy radius, in meters (m); is the gradient; is the Manning coefficient; is the wet perimeter in meters (m).

[0011] Optional, S4a. Determine the hydrogeological characteristics of the railway sections that are susceptible to floods and develop flood models to predict the likelihood and potential impacts of floods; S4b. Identify the most likely railway sections to be affected by disasters and the average maximum 24-hour rainfall over the past few years , coefficient of variation The ratio of the coefficient of skewness to the coefficient of variation ,in is the safety flow coefficient; S4c. Calculate different guarantee rates based on the design flood calculation method for small watersheds Designed for 24-hour rainfall Design flood ; S4d. Calculate the warning flood flow and rainfall probability. First, determine the warning flood flow How to decay over time from a peak value. Using the probability of rainfall and the maximum expected rainfall height in 24 hours , calculate the peak flood flow .

[0012] Optionally, the hydrogeological characteristics include rainfall intensity, terrain slope geographical parameters and runoff parameters.

[0013] The beneficial effects achieved by the present invention are as follows: the flood warning method provided by the present invention is aimed at disaster-prone sections of railways in areas without hydrological data, and significantly improves the accuracy and timeliness of flood control preparations by calculating and deducing early warning floods. First, the method conducts flood risk assessment based on the actual flood discharge capacity of disaster-prone sections of railways to ensure the scientificity and practicality of early warning measures. Secondly, by comprehensively adopting topographic, meteorological and watershed confluence models, the amount of rainstorm floods in areas without data is accurately calculated, providing the railway department with a new method for calculating early warning flood flow. In addition, the invention can calculate the corresponding early warning rainfall and flood control recurrence period according to the specific needs of disaster-prone sections of railways, thereby greatly improving the flood response capabilities along the railway, ensuring the safety and continuity of railway transportation, and also providing an important basis for relevant departments to formulate flood control strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 It is a flood investigation plan of a railway line susceptible to disasters in a specific implementation method of the water disaster early warning method along the railway in the area without hydrological data provided by the present invention.

[0016] Figure 2 It is a watershed map of the starting position K26+846 to K27+22 of a disaster-prone section of a certain railway in a specific implementation method of the water disaster early warning method along the railway in the area without hydrological data provided by the present invention.

[0017] Figure 3 It is a structural diagram of drainage facilities in a disaster-prone section of a railway in a specific implementation method of a water disaster early warning method along a railway in an area without hydrological data provided by the present invention.

[0018] Figure 4 The present invention discloses a water level-flow relationship curve of an open channel section, which is a specific implementation method of a water disaster early warning method along a railway in an area without hydrological data.

[0019] Figure 5 The invention discloses a design flood process line with different guarantee rates for a specific implementation method of a water disaster early warning method along a railway in an area without hydrological data. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0021] The terms "first" and "second" in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps, operations, components or modules is not limited to the listed steps, operations, components or modules, but may optionally include steps, operations, components or modules that are not listed, or may optionally include other steps, operations, components or modules that are inherent to these processes, methods, products or devices.

[0022] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] like Figures 1 to 5 As shown, an exemplary embodiment of a water disaster early warning method along a railway in an area without hydrological data comprises the following steps: S1. Determine the starting and ending locations of the disaster-prone sections of the railway.

[0024] Step S1 includes: S1a. Conduct field surveys along the railway to detect and record flood signs in the railway and surrounding areas. Figure 1 , which shows a flood survey plan for a vulnerable railway line.

[0025] S1b. Analyze field survey data and historical flood records to determine the starting and ending locations of the vulnerable railway sections. For example, the vulnerable section that can be determined is K26+846 to K27+22.

[0026] S1c. Combine the field survey results and historical flood data to accurately measure and mark the geographic coordinates of the start and end positions of the disaster-prone sections of the railway. Furthermore, the real-time dynamic global positioning system (RTK) is used for accurate measurement. For example, the geographic coordinates of the start and end positions of the disaster-prone section: starting position K26+846 (longitude: 125.563059, latitude: 43.755641) to K27+22 (longitude: 125.561554, latitude: 43.752178).

[0027] S2. Draw the flood catchment areas corresponding to the vulnerable railway sections.

[0028] Step S2 includes: S2a. Obtain and use a digital elevation model (DEM) map with a resolution of no less than 30 meters, which provides detailed elevation information of the disaster-prone sections of the railway and its surrounding terrain.

[0029] S2b. Using ArcGIS software, we draw a watershed map corresponding to the vulnerable railway section from the starting position K26+846 to the ending position K27+22 based on the DEM elevation data. The watershed map reveals the possible flood flow direction and waterlogging area, providing basic data for further risk assessment. Figure 2 A watershed map showing the starting position of a disaster-prone section of a railway from K26+846 to K27+22.

[0030] S3. Obtain the warning water level of drainage facilities in disaster-prone sections of the railway and calculate the warning flood flow.

[0031] Step S3 includes: S3a. Survey the drainage facilities in the affected sections of the railway and draw up a structural diagram of the drainage facilities to ensure that all relevant details are accurately recorded.

[0032] S3b. The hydraulic calculation formula is determined according to the drainage facility structure diagram, and the hydraulic parameters are calibrated in combination with the actual operation of the drainage facility (see Table 1). The drainage ditch meets the characteristics of an open channel, so the open channel constant flow formula is used to calculate the water flow capacity. The formula is as follows: in, is the water flow rate in cubic meters per second (m 3 / s); is the cross-sectional area of ​​the drainage ditch, in square meters (m 2 ); is Xiecai coefficient; is the water conservancy radius, in meters (m); is the gradient; is the Manning coefficient (roughness); is the wet perimeter in meters (m).

[0033] Table 1 shows an example of specific parameters of a drainage channel, including channel width, channel depth, gradient and roughness, and the calculated water flow rate.

[0034] S3c. According to the railway operation safety requirements, determine the upper limit of the safe flood flow level of the drainage facilities and the warning flood flow, that is, the warning water level, and deduce the warning flood flow. Since floods may cause surges, a certain safety superelevation is usually set in engineering to enhance flood control safety. In this example, the safety superelevation is 0.3 meters, so the warning water level is set to 0.5 meters (0.8 meters from the water surface to the bottom of the channel minus 0.3 meters of safety superelevation). According to the set warning water level, the calculation result of the warning flood flow is 0.460 cubic meters per second (m³ / s), see Table 2 for details.

[0035] Furthermore, in order to refine the analysis, the present invention proposes to perform step length calculation with a water depth increment of 0.01 meters. The calculation result is as follows: Figure 4 As shown in Table 2, the flow rate of the open channel at the highest water level reaches 0.814 cubic meters per second (m³ / s), which also represents its maximum water flow capacity.

[0036] Figure 4 The water level and flow relationship curve of the open channel section is displayed, providing an important visual reference for engineering design and risk assessment.

[0037] Table 2 shows the open channel flow data at different water level heights, which is used to evaluate the water flow capacity under various water level conditions. The water level measurement range is from 0.0 m to 0.8 m, and the relationship between the flow rate and the flow rate is recorded in detail. The flow rate measurement range is from 0.0 cubic meters per second to 0.814 cubic meters per second.

[0038] From the data in the table, it can be seen that as the water level rises, the flow capacity of the open channel increases accordingly. In particular, when the safety warning water level is 0.5 meters, the flow rate reaches 0.460 cubic meters per second, and when the highest water level is 0.8 meters, the flow rate of the open channel reaches a maximum value of 0.814 cubic meters per second.

[0039] In addition, the table can also be used for step length calculation to determine the growth trend of flow under gradually increasing water level conditions, thereby providing accurate data support and risk assessment basis for engineering design.

[0040] S4. Obtain the rainstorm return period.

[0041] Step S4 includes: S4a. Determine the hydrogeological characteristics of the vulnerable sections of the railway, including rainfall intensity, terrain slope geographical parameters, and confluence parameters. Based on the above parameters, a flood model is established to predict the possibility and potential impact of floods. As shown in Table 3, the table lists the key parameters such as regional rainfall and terrain characteristics.

[0042] S4b. Calculate the early warning flood flow. This step includes hydraulic analysis of drainage facilities to ensure that they can effectively handle the predicted flood volume. According to the local hydrological manual, find out the average maximum 24-hour rainfall in the vulnerable railway section over the years. , coefficient of variation The ratio of the coefficient of skewness to the coefficient of variation ,in is the safety flow coefficient.

[0043] Based on the obtained risk factor and actual rainfall conditions, calculate the warning flood flow that may affect the vulnerable areas The calculations are based on a 24-hour rainfall event, taking into account runoff effects and topographic influences, ensuring that the warning system reflects immediate hydrological conditions and safety needs.

[0044] S4c. First determine the maximum rainfall height that may occur within 24 hours Based on this data, the corresponding warning flood flow is calculated , based on historical rainfall data and statistical probability models, allows railway managers to assess the possible flood risks under different rainfall scenarios.

[0045] See also Figure 5 , different guarantee rates Design flood process line.

[0046] Table 6 shows the rainfall probability under five different Conditions, early warning flood flow How it changes over time. Flow data (unit: m³ / s) is recorded minute by minute, from zero to 130 minutes, and details the peak flow of floods and their decay process.

[0047] S4d. Calculate the warning flood flow and rainfall probability. First, determine the warning flood flow How to decay over time from a peak value. Using the probability of rainfall and the maximum expected rainfall height in 24 hours , calculate the peak flood flow .

[0048] According to the calculation results of step 3.3 (Table 2), when the highest observed rainfall intensity is 0.766 m³ / s, please refer to Table 6, the flood flow peak of 0.763 m³ / s is reached at the 40th minute. This shows that even when the rainfall intensity decreases slightly, the flood flow is still close to the peak value. At this time, the flood is defined as a warning flood, corresponding to the warning rainstorm of 28.286 mm / d, that is, the design 24-hour rainfall, and the recurrence period is once a year. After verification with relevant departments, this data is consistent with the flooding along the railway, that is, it is flooded every year.

[0049] In summary, the present invention proposes a method for early warning of flood disasters along railways in areas without hydrological data. This example is only an example of the method described in this patent. With the continuous accumulation of flood monitoring data in vulnerable railway sections, when the sample capacity adequacy is properly met, the rationality and reliability of the early warning rainstorm deduction results will be improved.

[0050] The flood warning method provided by the present invention is aimed at disaster-prone sections of railways in areas without hydrological data, and significantly improves the accuracy and timeliness of flood control preparations by calculating and deducing warning floods. First, the method conducts flood risk assessment based on the actual flood discharge capacity of disaster-prone sections of railways to ensure the scientificity and practicality of early warning measures. Secondly, by comprehensively adopting topographic, meteorological and watershed confluence models, the amount of rainstorm floods in areas without data is accurately calculated, providing the railway department with a new method for calculating early warning flood flow. In addition, the invention can calculate the corresponding early warning rainfall and flood control recurrence period according to the specific needs of disaster-prone sections of railways, thereby greatly improving the flood response capabilities along the railway, ensuring the safety and continuity of railway transportation, and also providing an important basis for relevant departments to formulate flood control strategies.

[0051] The exemplary embodiments of the present application may be combined with each other, and the exemplary embodiments obtained by the combination also fall within the scope of the present application.

[0052] This application uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core idea of ​​this application. At the same time, for technical personnel in this field, according to the idea of ​​this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on this application.

Claims

1. A method for early warning of flood hazards along railways in areas without hydrological data, characterized in that: The steps include: S1. Determine the starting and ending locations of the disaster-prone sections of the railway; S2. Draw the flood catchment areas corresponding to the vulnerable railway sections; S3. Obtain the warning water level of drainage facilities in the disaster-prone sections of the railway and calculate the warning flood flow; S4. Obtain the rainstorm recurrence period for early warning.

2. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 1, characterized in that: The step S1 comprises: S1a. Conduct field surveys along the railway to detect and record flood signs in the railway and surrounding areas; S1b. Analyze field survey data and historical flood records to determine the start and end locations of vulnerable railway sections. S1c. Combine field survey results with historical flood data to accurately measure and mark the geographic coordinates of the start and end locations of disaster-prone sections of the railway.

3. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 1, characterized in that: The step S2 comprises: S2a. Obtain elevation information of the disaster-prone sections of the railway and its surrounding terrain; S2b. Draw a watershed map of the vulnerable railway section from the starting location to the end location.

4. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 1, characterized in that: Step S3 includes: S3a. Measure the drainage facilities in the affected railway section and draw a structural diagram of the drainage facilities; S3b. Calculate the water flow capacity according to the drainage facility structure diagram; S3c. Determine the upper limit of safe flood discharge level of drainage facilities and the warning flood flow.

5. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 4, characterized in that: The drainage facility of S3b is an open channel, and the calculation formula of the water flow capacity of the open channel is: in, is the water flow rate in cubic meters per second (m 3 / s); is the cross-sectional area of ​​the drainage ditch, in square meters (m 2 ); is Xiecai coefficient; is the water conservancy radius, in meters (m); is the gradient; is the Manning coefficient; is the wet perimeter in meters (m).

6. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 1, characterized in that: The step S4 comprises: S4a. Determine the hydrogeological characteristics of the railway sections that are vulnerable to floods and establish flood models to predict the likelihood and potential impact of floods; S4b. Identify the most likely railway sections to be affected by disasters and the average maximum 24-hour rainfall over the past few years , coefficient of variation The ratio of the coefficient of skewness to the coefficient of variation ,in is the safety flow coefficient; S4c. Calculate different guarantee rates based on the design flood calculation method for small watersheds Designed for 24-hour rainfall Design flood ; S4d. Calculate the warning flood flow and rainfall probability. First, determine the warning flood flow How to decay over time from a peak value. Using the probability of rainfall and the maximum predicted rainfall height in 24 hours , calculate the peak flood flow .

7. The method for early warning of flood hazards along railway lines in areas without hydrological data according to claim 6, characterized in that: The hydrogeological characteristics include rainfall intensity, terrain slope geographical parameters and runoff parameters.

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