A method for extracting and emergency handling of flooded water areas around subway stations

Abstract

The present invention discloses a method for extracting and handling waterlogging ranges around subway stations and emergency response, comprising determining key points around subway stations that cause waterlogging at subway stations, collecting elevation values ​​and coordinates of the key points; calculating the depth of surface waterlogging within the boundary range of a catchment area where the subway station is located; calculating the depth of waterlogging in the catchment area, establishing a spatial intersection of the key points and the depth of surface waterlogging within the boundary range of the catchment area where the subway station is located, and extracting the depth of waterlogging at the key points; automatically matching emergency response measures based on the depth of waterlogging at the key points to prevent waterlogging at the subway station. The present application clarifies the spatial information of key points around subway stations, spatially locates the coordinates of the key points and a surface waterlogging depth layer, compares the relationship between the elevation of the key points and the waterlogging depth, extracts the depth of waterlogging at the key points, and proposes corresponding emergency response measures according to the flooding depths of different key points.

Description

Technical Field

[0001] The invention relates to the technical field of preventing waterlogging from flooding at subway stations, and in particular to a method for extracting and handling waterlogging areas around subway stations. Background Art

[0002] With the acceleration of urbanization, subway stations are key points in urban transportation networks, and their safety and reliability are crucial to urban operations. However, due to extreme weather events, such as heavy rains and storm surges, water may accumulate in the areas around subway stations, affecting the normal operation of subway stations and the safety of passengers. Especially in areas with low terrain or poor drainage systems, subway stations and their surrounding areas are prone to water accumulation or even flooding, which not only affects the normal travel of passengers, but may also cause serious safety accidents. Therefore, it is particularly important to develop an effective method for extracting the flooding range and emergency disposal of key points around subway stations.

[0003] At present, the following methods are mainly used to analyze the flooding impact range around subway stations:

[0004] 1. Estimation method based on empirical formula: This method relies on historical data and expert experience, and predicts what may happen in the future by summarizing the water accumulation patterns in similar situations in the past;

[0005] 2. Finite element analysis: The finite element method is used to simulate groundwater flow and soil permeability, which is particularly suitable for evaluating the impact of rising groundwater levels on subway station structures.

[0006] The current methods have the following disadvantages:

[0007] 1. Although this method is simple and easy to implement, due to the lack of detailed consideration of specific environmental factors, its prediction accuracy is relatively low and it is difficult to meet the needs of refined management;

[0008] 2. Although finite element analysis is powerful in simulating groundwater flow and soil permeability, it has shortcomings and limitations such as input data accuracy, professional skill requirements, heterogeneity challenges, multi-scale issues, computational cost and time, software and method selection, model complexity, and accuracy of seismic fragility curves.

[0009] Therefore, a refined and highly accurate method for extracting the flooding range around subway stations and emergency response is needed. Summary of the invention

[0010] The purpose of the present invention is to provide a method for extracting and handling the flooded area around a subway station in an emergency, so as to solve the problems raised in the above-mentioned background technology.

[0011] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a method for extracting and emergency handling of the flooded area around a subway station, comprising:

[0012] S1: Determine the key points around the subway station that cause flooding in the subway station, and collect the elevation values ​​and coordinates of the key points;

[0013] S2: Calculate the depth of surface water within the boundary of the catchment area where the subway station is located;

[0014] S3: Calculate the water depth of the catchment area, establish the spatial intersection of the key points and the surface water depth within the boundary of the catchment area where the subway station is located, and extract the water depth of the key points;

[0015] S4: Automatically match emergency response measures based on the water depth at key points to prevent subway stations from being flooded.

[0016] This application clarifies the spatial information of key points around subway stations through detailed collection of elevation values ​​and coordinate positions of key points around subway stations, calculates the surface water depth, spatially locates the coordinates of key points and the surface water depth layer, compares the relationship between the elevation of key points and the water depth, extracts the water inundation depth of key points, and proposes corresponding emergency response measures according to the inundation depth of different key points.

[0017] Preferably, key points around the subway station that cause waterlogging in the subway station are preliminarily confirmed based on the planning and design of the subway station, and secondary adjustments are made when extracting the water depth at the key points to achieve refined adjustment of the key points with higher accuracy, which is conducive to accurate matching of subsequent emergency response measures.

[0018] Preferably, determining the boundary of the catchment area where the subway station is located includes:

[0019] S2.1: Directly obtain or define several first-level drainage zones based on the location of the subway station;

[0020] S2.2: Divide each primary drainage area into relatively independent mesoscale units to form secondary subcatchments;

[0021] S2.3: Spatially match the coordinates of the subway station with the secondary sub-catchment area to clarify the boundary of the catchment area where the subway station is located.

[0022] Preferably, the first-level drainage zones are defined based on the location of the subway station, including:

[0023] S2.11: Determine the watershed to which the subway station belongs, and delineate a number of waterlogging zoning units based on the watershed zoning and the natural and administrative boundaries of the city;

[0024] S2.12: Delineate several canal drainage zones within the waterlogging zone unit, and extract the canal drainage zone where the subway station is located as the boundary of the first-level drainage zone.

[0025] Preferably, the method for delineating the secondary sub-catchment includes: spatially matching the coordinates of the subway station with the primary drainage division, clarifying the primary drainage division where the subway station is located as the boundary condition for generating the secondary sub-catchment, taking the primary drainage division as the basis, based on the sample points within the primary drainage division, using the Thiessen polygon tool in the GIS tool, dividing the secondary sub-catchment according to the location of the sample points, ensuring that there is only one sample point in each polygon, and any position in the polygon is closest to the sample point, and further dividing each primary drainage division into relatively independent units of medium scale to form a secondary sub-catchment.

[0026] Preferably, the key points that are initially confirmed include subway station entrances and exits, emergency evacuation passages, wind shelters and cooling towers, off-site security areas, parking lots, municipal drainage network exits, low-lying areas and areas prone to water accumulation, identification of road intersections, positioning of entrances and exits of urban public service facilities, and the center point, lowest point, and highest point of sunken plaza facilities.

[0027] Preferably, after extracting the water depth of the key point, it is determined whether there are other points whose water depth difference with the key point is within the set threshold range. If so, the points whose water depth difference is within the set threshold range are extracted as supplementary key points.

[0028] Preferably, calculating the water depth of the catchment area includes:

[0029] A1: Rasterize the watershed area to obtain the DEM elevation pixel value of the watershed area;

[0030] A2: Calculate the total precipitation in the catchment area , Total drainage volume of drainage pipes in the catchment area And calculate the total surface flow of the catchment area , ;

[0031] A3: Arrange the DEM elevation pixel values ​​of the catchment area from large to small, and calculate the passive flooding depth starting from the smallest DEM elevation pixel value to obtain the i-th passive flooding depth of the catchment area. and the total inundation of the elevation raster Calculate, when , then continue to calculate the water depth. , the calculation of water depth is completed. At this time, As the maximum water depth.

[0032] Preferably, establishing a spatial intersection of the key point and the surface water depth within the boundary range of the catchment area where the subway station is located, and extracting the water depth of the key point includes:

[0033] B1: Based on the elevation information of key points, draw the height lines and rasterize them to obtain the key point distribution grid;

[0034] B2: Perform spatial intersection between the key point distribution grid and the catchment area grid, and obtain the water depth of the key points based on the water depth of the catchment area.

[0035] Preferably, the depth of accumulated water is divided into shallow water areas and deep water areas, and emergency response measures are matched according to the types of key points.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. This application collects the elevation values ​​and coordinate positions of key points around the subway station in a refined manner, clarifies the spatial information of key points around the subway station, calculates the surface water depth, spatially locates the coordinates of the key points and the surface water depth layer, compares the relationship between the elevation of the key points and the water depth, extracts the water inundation depth of the key points, and proposes corresponding emergency response measures according to the inundation depth of different key points;

[0038] 2. After the initial confirmation of the key points, this application makes a secondary adjustment when extracting the water depth of the key points, so as to achieve a refined adjustment of the key points with higher accuracy, which is conducive to the subsequent accurate matching of emergency response measures;

[0039] 3. This application uses elevation point data collection and geographic positioning technology to determine the spatial attributes of specific key point types, which can accurately describe the impact of the flooding depth of key points around the subway station on the normal operation of the subway station, providing a solid foundation for subsequent analysis and emergency response;

[0040] 4. This application can obtain the flooding depth of important key points by conducting a refined spatial intersection analysis of key points around the subway station and the water depth data, and clarify the affected geographical elements around the subway station, providing strong technical support for the refined formulation of emergency rescue plans;

[0041] 5. This application formulates corresponding emergency response measures according to the different flooding depths to ensure the safe operation of subway stations under extreme weather conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A flowchart of the steps in a method for extracting the flooded area around a subway station and emergency treatment proposed by the present invention;

[0043] Figure 2 A schematic diagram of key point delineation in a method for extracting the flooding range around a subway station and emergency disposal proposed by the present invention;

[0044] Figure 3 A schematic diagram of the delineation of primary drainage zones in a method for extracting the flooding range around a subway station and for emergency disposal proposed by the present invention;

[0045] Figure 4 A schematic diagram of delineating secondary sub-catchment areas in a method for extracting the flooding range around a subway station and for emergency disposal proposed by the present invention;

[0046] Figure 5 A schematic diagram of the boundary delineation of the water catchment area where the subway station is located in a method for extracting the flooded area around the subway station and emergency disposal proposed by the present invention;

[0047] Figure 6 A schematic diagram of the DEM grid flooding depth in a method for extracting the flooding range around a subway station and emergency disposal proposed by the present invention;

[0048] Figure 7 A schematic diagram of a grid of waterlogging depth in a method for extracting waterlogging range around a subway station and for emergency disposal proposed by the present invention;

[0049] Figure 8 This is a schematic diagram of the elevation grid of key points in a method for extracting the flooding range around a subway station and dealing with emergency situations proposed by the present invention;

[0050] Fig. 9 It is a schematic diagram of water depth at key points obtained by the intersection of key point elevation grid and water inundation depth grid in a method for extracting water inundation range around subway stations and emergency disposal proposed by the present invention. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] The present invention provides a method for extracting and emergency handling of the flooded area around a subway station. Figure 1 As shown, including:

[0053] S1: Determine the key points around the subway station that cause waterlogging at the subway station, and collect the elevation values ​​and coordinates of the key points, including: Based on the "GB / T50308-2017 Urban Rail Transit Engineering Survey Specification", "Subway Design Specification" GB50157, urban waterlogging prevention and control design, urban waterlogging model, excessive rainwater prevention and warning system and other standards and policies, identify the subway station entrances and exits, emergency evacuation passages, wind pavilions and cooling towers, off-station security inspection areas, parking lots, municipal drainage network exits, low-lying areas and areas prone to waterlogging, identify road intersections, locate the entrances and exits of urban public service facilities, the center point, lowest point, and highest point of facilities such as sunken squares as the key points around the subway station that cause waterlogging at the subway station, such as Figure 2 As shown, the elevation values ​​and coordinate positions of key points are collected by on-site surveying using instruments such as total stations or GPS receivers. The star symbols in the figure represent subway stations, and dots of different colors represent key points.

[0054] S2: Calculate the depth of surface water within the boundary of the catchment area where the subway station is located, including:

[0055] Determine the boundaries of the catchment area where the subway station is located:

[0056] S2.1: Directly obtain or delineate several first-level drainage zones based on the location of subway stations. Direct acquisition specifically includes: the delineation standards of first-level drainage zones refer to the "Drainage (Rainwater) Flood Control Comprehensive Plan" of each city, and the plan includes the specific scope of all first-level drainage zones in the city.

[0057] If you need to define the location of the subway station yourself, the steps are as follows: Figure 3 As shown in the figure, first determine the watershed to which the subway station belongs according to the urban area where the subway station is located. On the basis of the watershed division, combine the natural and administrative divisions such as the urban backbone water system and ridgeline, focus on the development boundary range, and delineate several waterlogging division units. Combined with the distribution of water systems, vertical conditions, and the current distribution of pipes and canals, follow the principle of "high water and high drainage, low water and low drainage", and delineate several pipe and canal drainage divisions within the waterlogging division. The pipe and canal drainage division where the subway station is located is extracted as the division boundary of the first-level drainage division. The star symbol in the figure represents the subway station, the left side of the figure is a schematic diagram of the division boundary, and the right side of the figure is a schematic diagram of the first-level drainage division delineation.

[0058] S2.2: If Figure 4As shown, each first-level drainage area is divided into relatively independent units of mesoscale to form a secondary sub-catchment area, specifically including: taking a certain first-level drainage area where the subway station under study is located as the boundary condition for generating the secondary sub-catchment area, taking the first-level catchment area as the basis, using the sample points within the first-level drainage area, using the Thiessen polygon tool in the GIS tool, and dividing the secondary sub-catchment area according to the location of the rainwater well, ensuring that there is only one sample point in each polygon. In this embodiment, the rainwater well is used as the sample point, and any position in the polygon is closest to the sample point. Each first-level drainage area is further divided into relatively independent units of mesoscale to form a secondary sub-catchment area.

[0059] S2.3: If Figure 5 As shown, the coordinates of the subway station are spatially matched with the secondary sub-catchment area to clarify the boundary of the catchment area where the subway station is located. The catchment area boundary is the boundary range of a secondary sub-catchment area where the subway station is located.

[0060] S3: Calculate the water depth of the catchment area, establish the spatial intersection of the key points and the surface water depth within the boundary of the catchment area where the subway station is located, and extract the water depth of the key points.

[0061] The calculation of water depth in the catchment area includes:

[0062] A1: Rasterize the catchment area to obtain the DEM elevation pixel value of the catchment area. Digital elevation model analysis is a technology that uses remote sensing technology and geographic information system platform to analyze terrain features. This technology generates a continuous terrain surface model by acquiring and processing surface elevation data, thereby determining low-lying areas and water flow directions, and then predicting possible waterlogging areas;

[0063] A2: Due to the particularity of the subway station, most of the key points around it are impermeable surfaces. Assuming that their permeability is 0, without considering the surface infiltration, the surface runoff is mainly related to the precipitation in the catchment area and the drainage volume of the drainage pipe. Calculate the total precipitation in the catchment area in turn: , ,in, is the total catchment area; is the total rainfall, the unit of total rainfall is mm. Calculate the total drainage volume of the drainage pipe in the catchment area , ,in, is the diameter of the rainwater pipe, is the drainage speed of the rainwater pipe. The minimum design flow rate of the rainwater pipe at full flow should be 0.75 m / s, and the maximum design flow rate of the non-metallic pipe is 5.0 m / s. The specific design flow rate should be selected according to the design standards of the drainage network around the local subway station. Calculate the total surface flow of the catchment area , .

[0064] A3: Arrange the DEM elevation pixel values ​​of the catchment area from large to small, and start the passive flooding depth calculation from the smallest DEM elevation pixel value, such as Figure 6 and 7 As shown in the figure, the i-th passive flooding depth of the catchment area is calculated. and the total inundation of the elevation raster Calculation, specifically:

[0065] ,

[0066] in, The number of times passive flooding is calculated; is the area of ​​the raster pixel.

[0067] when , then continue to calculate the water depth. , the calculation of water depth is completed. At this time, As the maximum water depth, the flooding depth value of a single pixel can be expressed as , Represents the elevation value of the pixel for which passive inundation depth calculation is required.

[0068] Establish the spatial intersection of the key points and the surface water depth within the boundary of the catchment area where the subway station is located, and extract the water depth of the key points, such as Figure 8 and 9 As shown, specifically including:

[0069] B1: Based on the elevation information of key points, draw the height lines and rasterize them to obtain the key point distribution grid;

[0070] B2: Perform spatial intersection between the key point distribution grid and the catchment area grid, and extract the water depth of the key points based on the water depth of the catchment area.

[0071] It should be noted that after extracting the water depth of the key point, it is determined whether there are other points whose water depth difference with the key point is within the set threshold range. If so, the points whose water depth difference is within the set threshold range are extracted as key points.

[0072] S4: Automatically match emergency response measures based on the water depth of key points to prevent subway stations from being flooded. Specifically, the water depth is divided into shallow water areas and deep water areas, and emergency response measures are matched according to the types of key points. The specific matching method is as follows:

[0073] .

[0074] In summary, the present invention adopts a refined spatial intersection analysis method to conduct a detailed analysis of key points around the subway station and obtain the flooding depth of important key points. This method can clearly identify the affected geographical elements around the subway station and provide strong technical support for the refined formulation of emergency rescue plans.

[0075] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for extracting and handling flooded areas around a subway station, characterized in that: include: S1: Determine the key points around the subway station that cause flooding in the subway station, and collect the elevation values ​​and coordinates of the key points; S2: Calculate the water depth of the catchment area within the catchment area boundary of the subway station. The calculation of the water depth of the catchment area includes: A1: Rasterize the watershed area to obtain the DEM elevation pixel value of the watershed area; A2: Calculate the total precipitation in the catchment area , Total drainage volume of drainage pipes in the catchment area And calculate the total surface flow of the catchment area , ; A3: Arrange the DEM elevation pixel values ​​of the catchment area from large to small, and calculate the passive flooding depth starting from the smallest DEM elevation pixel value to obtain the i-th passive flooding depth of the catchment area. and the total inundation of the elevation raster Calculate, when , then continue to calculate the water depth. , the calculation of water depth is completed. At this time, as the maximum depth of water accumulation; S3: Establish the spatial intersection of the key points and the water depth of the catchment area within the boundary of the catchment area where the subway station is located, and extract the water depth of the key points; S4: Automatically match emergency response measures based on the water depth at key points to prevent subway stations from being flooded.

2. The method for extracting and handling flooded areas around a subway station according to claim 1, characterized in that: The key points around the subway stations that cause waterlogging at the subway stations are initially confirmed based on the planning and design of the subway stations, and secondary adjustments are made when extracting the water depth at the key points.

3. A method for extracting and handling flooded areas around a subway station according to claim 1 or 2, characterized in that: The determination of the catchment area boundary of the subway station includes: S2.1: Directly obtain or define several first-level drainage zones based on the location of the subway station; S2.2: Divide each primary drainage area into relatively independent mesoscale units to form secondary subcatchments; S2.3: Spatially match the coordinates of the subway station with the secondary sub-catchment area to clarify the boundary of the catchment area where the subway station is located.

4. The method for extracting and handling flooded areas around a subway station according to claim 3 is characterized by: The first-level drainage zones are delineated based on the location of the subway station, including: S2.11: Determine the watershed to which the subway station belongs, and delineate a number of waterlogging zoning units based on the watershed zoning and the natural and administrative boundaries of the city; S2.12: Delineate several canal drainage zones within the waterlogging zone unit, and extract the canal drainage zone where the subway station is located as the boundary of the first-level drainage zone.

5. The method for extracting and handling flooded areas around a subway station according to claim 4, characterized in that: The method for delineating the secondary sub-catchment area includes: spatially matching the coordinates of the subway station with the primary drainage division, clarifying the primary drainage division where the subway station is located as the boundary condition for generating the secondary sub-catchment area, taking the primary drainage division as the basis, based on the sample points within the primary drainage division, using the Thiessen polygon tool in the GIS tool, dividing the secondary sub-catchment area according to the location of the sample points, ensuring that there is only one sample point in each polygon, and any position in the polygon is closest to the sample point, and further dividing each primary drainage division into relatively independent units of medium scale to form a secondary sub-catchment area.

6. A method for extracting and handling flooded areas around a subway station according to claim 1 or 2, characterized in that: The key points preliminarily confirmed include subway station entrances and exits, emergency evacuation passages, wind shelters and cooling towers, off-site security areas, parking lots, municipal drainage network exits, low-lying areas and areas prone to water accumulation, identification of road intersections, positioning of entrances and exits of urban public service facilities, and the center, lowest point, and highest point of sunken plaza facilities.

7. A method for extracting and handling flooded areas around a subway station according to claim 6, characterized in that: After extracting the water depth of the key point, determine whether there are other points whose water depth difference with the key point is within the set threshold range. If so, extract the points whose water depth difference is within the set threshold range as the key point.

8. The method for extracting and handling flooded areas around a subway station according to claim 1, characterized in that: Establish the spatial intersection of the key points and the surface water depth within the boundary of the catchment area where the subway station is located, and extract the water depth of the key points, including: B1: Based on the elevation information of key points, draw the height lines and rasterize them to obtain the key point distribution grid; B2: Perform spatial intersection between the key point distribution grid and the catchment area grid, and obtain the water depth of the key points based on the water depth of the catchment area.

9. A method for extracting and handling flooded areas around a subway station according to claim 8, characterized in that: The depth of accumulated water is divided into shallow water areas and deep water areas, and emergency response measures are matched according to the types of key points.

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