Vertical elevation calculation method and device for super-large city and calculation equipment

Abstract

The invention belongs to the technical field of urban planning, and discloses a vertical elevation calculation method and device for an ultra-large city and calculation equipment. Hydrological analysis and slope analysis are carried out by obtaining processed geographic space data in a research range to obtain catchment subareas and slope analysis data, and the slope type of each catchment subarea is determined through catchment subarea superposition slope analysis; drawing a rainwater drainage path of each water collection subarea in combination with the gradient type of each water collection subarea, determining calculation points, and extracting a current situation elevation value of each calculation point; determining the design elevation of each calculation point by combining the elevation of the rainwater discharge outlet and the current elevation of the calculation point, and finally generating designed target terrain grid data; urban vertical planning control points are determined through road traffic data, and control elevations of the control points are determined. By adopting the embodiment of the invention, a calculation reference can be provided for the vertical planning in the whole city through the vertical planning control point, and the problem that the vertical planning lacks overall consideration is solved.

Description

Technical Field

[0001] The present application relates to the field of urban planning technology, and in particular to a method, device and computing equipment for calculating vertical elevations of a megacity. Background Art

[0002] Urban vertical planning plays an important and positive role in solving urban waterlogging problems. In recent years, urban waterlogging caused by frequent excessive rainfall has caused serious waterlogging disasters in major cities, and urban vertical planning has gradually received widespread attention from the society.

[0003] In the early stages of urbanization, vertical planning was mainly prepared separately for each area. Due to the lack of overall coordination and design at a higher level in urban vertical planning, the traditional vertical elevation calculation method has shortcomings such as inconsistent control element standards and insufficient overall consideration, which can easily lead to relatively low-lying local areas in later construction. Megacities generally have the characteristics of dense urban population, high urbanization, and complex and diverse topography, and the vertical planning problems they face are more prominent. Therefore, an effective method is needed to comprehensively consider the vertical planning influencing factors such as the city's terrain characteristics, rainwater discharge needs, and current construction, unify the vertical elevation calculation benchmark, and solve the problem of lack of overall consideration in vertical planning. Summary of the invention

[0004] To this end, the embodiments of the present application provide a method, device and computing equipment for calculating the vertical elevation of a megacity, so that the calculated elevation value is more systematic and holistic, providing guidance and basis for the preparation of urban vertical planning.

[0005] In a first aspect, the present application provides a method for calculating vertical elevations for a megacity.

[0006] This application is achieved through the following technical solutions:

[0007] A vertical elevation calculation method for a megacity, comprising:

[0008] Acquire geospatial data within the research scope, preprocess the geospatial data, and obtain preprocessed geospatial data; wherein the geospatial data includes terrain data, river system data, road traffic data, and rainwater pipe network data;

[0009] Analyze the preprocessed geospatial data to obtain the watershed division results and slope analysis results. Based on the slope analysis results, convert the raster map into slope vector surface data. Then, analyze the watershed division results based on the slope vector surface data to obtain the slope type of each watershed division.

[0010] Based on the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment area, the rainwater discharge path of each catchment area is drawn, the calculation points of the vertical elevation are determined based on the rainwater discharge path, and the current elevation value of each calculation point is extracted;

[0011] According to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point, determine the design elevation value of each calculation point along the rainwater discharge path;

[0012] The target terrain grid data is generated based on the design elevation value, the intersections of the main roads and the secondary roads are determined through the road traffic data, the intersections are used as control points of the urban vertical master plan, and the control elevation values ​​of the control points are determined through the target terrain grid data.

[0013] In a preferred example of the present application, it can be further configured that the acquiring of the geospatial data within the research scope and preprocessing of the geospatial data to obtain the preprocessed geospatial data include:

[0014] Obtain terrain data, river system data, road traffic data and rainwater pipe network data in the same geographic coordinate system within the research scope;

[0015] Erasing the elevated bridge surface and river system surface data in the road traffic data from the terrain data, and using the difference method to regenerate the terrain data within the research scope;

[0016] The starting point and the end point of the rainwater pipe network vector line are determined from the rainwater pipe network data, wherein the starting point of the rainwater pipe network vector line is set as the discharge outlet of the rainwater pipe network, and the end point of the rainwater pipe network vector line is set as the starting point of the rainwater pipe network.

[0017] In a preferred example of the present application, it can be further configured that the pre-processed geographic spatial data is analyzed to obtain the watershed partition results and slope analysis results, the raster map is converted into slope vector surface data based on the slope analysis results, and then the watershed partition results are analyzed based on the slope vector surface data to obtain the slope type of each watershed partition, including:

[0018] The hydrological analysis tools in ArcGIS were used to perform depression filling, water collection analysis and flow direction analysis on the pre-processed geospatial data to determine the rainwater catchment zones.

[0019] Use the surface analysis tool in ArcGIS to perform slope analysis on the preprocessed geospatial data and output the slope analysis results;

[0020] The slope analysis results are converted into integer slope data, and the integer slope data is converted into slope vector surface data through the raster to surface tool in ArcGIS. Based on the slope vector surface data, the research area is divided into plain area, gentle slope area and steep slope area;

[0021] The slope vector surface data of each rainwater catchment zone is obtained, and the proportion of plain area, gentle slope area and steep slope area in the rainwater catchment zone is analyzed to obtain the slope type of the rainwater catchment zone.

[0022] In a preferred example of the present application, it can be further configured that the research scope is divided into a plain area, a gentle slope area and a steep slope area based on the slope vector surface data, including:

[0023] When the slope vector surface data is between 0 and 0.003, the corresponding research range is determined to be a plain area;

[0024] When the slope vector surface data is between 0.003 and 0.03, the corresponding research range is determined to be a gentle slope area;

[0025] When the slope vector surface data is greater than 0.03, the corresponding research range is determined to be a steep slope area.

[0026] In a preferred example of the present application, it can be further configured to determine the calculation points of the vertical elevation based on the rainwater discharge path, and extract the current elevation value of each calculation point, including:

[0027] Use the Generate Points Along Line tool in ArcGIS to generate a calculation point every 50 meters along the stormwater drainage path, and number the starting point to the end point from small to large;

[0028] The sampling tool in ArcGIS was used to extract the current elevation value of each calculation point.

[0029] In a preferred example of the present application, it can be further configured that the design elevation value of each calculation point along the rainwater discharge path is determined according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point, including:

[0030] Using the identification tool in ArcGIS, the calculation point of vertical elevation is used as input data, and the urban spatial attribute is used as the identification item to generate the vertical elevation calculation point with spatial attributes. The attribute field belonging to the built-up area is assigned to 1, and the attribute field not belonging to the built-up area is assigned to 0.

[0031] Export the vertical elevation calculation points with spatial attributes to an Excel file, and filter the data in the Excel file using Python;

[0032] Read the first value in the object column in the Excel file, subtract the first value from each value in the object column and assign them to the number column starting from 0;

[0033] Create a height difference column, multiply the value of the number column by 0.05 and assign it to the height difference column;

[0034] Create the discharge outlet elevation, and assign the corresponding elevation value of the number column numbered 0 to the discharge outlet elevation;

[0035] Create calculated elevation columns and design elevation columns, and determine the calculated elevation values ​​and design elevation values ​​of the calculation points row by row according to preset rules.

[0036] In a preferred example of the present application, it can be further set as follows:

[0037] Determine the design elevation values ​​of the calculation points row by row according to the preset rules, including:

[0038] When the calculated elevation value is less than the current elevation value and the space attribute is 1, the design elevation value is equal to the current elevation value;

[0039] When the calculated elevation value is less than the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value;

[0040] When the calculated elevation value is greater than or equal to the current elevation value, and the space attribute is 1, the design elevation value is equal to the calculated elevation value;

[0041] When the calculated elevation value is greater than or equal to the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value.

[0042] In a preferred example of the present application, it can be further set as follows:

[0043] The method of generating target terrain grid data based on the design elevation value, determining the intersection of the main road and the secondary road through the road traffic data, using the intersection as the control point of the urban vertical master plan, and determining the control elevation value of the control point through the target terrain grid data includes:

[0044] The target terrain raster data is generated based on the design elevation value of the calculation point using the triangle grid method in ArcGIS, and the target terrain raster data is preprocessed for filling depressions.

[0045] Extract the intersections of main roads and secondary roads from road traffic data as control points for urban vertical planning within the research scope;

[0046] The design elevation values ​​corresponding to the control points are extracted from the target terrain raster data after the preprocessing of the filling process as the control elevation values ​​of the control points, which are used to guide the vertical planning of the city.

[0047] In a second aspect, the present application provides a vertical elevation calculation device for a megacity.

[0048] This application is achieved through the following technical solutions:

[0049] A vertical elevation calculation device for a megacity, used to execute the method described in the first aspect, comprising:

[0050] A data acquisition module is used to acquire geospatial data within the research scope, preprocess the geospatial data, and obtain preprocessed geospatial data; wherein the geospatial data includes terrain data, river system data, road traffic data, and rainwater pipe network data;

[0051] The data analysis module is used to analyze the pre-processed geographic spatial data to obtain the watershed partition results and slope analysis results, convert the raster map into slope vector surface data based on the slope analysis results, and then analyze the watershed partition results based on the slope vector surface data to obtain the slope type of each watershed partition;

[0052] The current elevation extraction module is used to draw the rainwater discharge path of each catchment zone according to the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment zone, determine the calculation points of the vertical elevation based on the rainwater discharge path, and extract the current elevation value of each calculation point;

[0053] A design elevation determination module is used to determine the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point;

[0054] The control elevation calculation module is used to generate target terrain grid data based on the design elevation value, determine the intersection of the main road and the secondary road through road traffic data, use the intersection as the control point of the urban vertical master plan, and determine the control elevation value of the control point through the target terrain grid data.

[0055] On the third aspect, the present application is realized through the following technical solutions:

[0056] A vertical elevation calculation device for a megacity comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the methods of the first aspect when executing the computer program.

[0057] In summary, compared with the prior art, the technical solution provided in the embodiment of the present application has at least the following beneficial effects:

[0058] This application obtains the geospatial data of the research scope, pre-processes the geospatial data, and obtains the pre-processed geospatial data; analyzes the pre-processed geospatial data to obtain the watershed division results and slope analysis results, converts the raster map into slope vector surface data based on the slope analysis results, and then analyzes the watershed division results based on the slope vector surface data to obtain the slope type of each watershed division; according to the slope vector surface data, combined with the slope type of each watershed division, river system data and road traffic data, draws the rainwater discharge path of each watershed division, determines the calculation points of the vertical elevation based on the rainwater discharge path, and extracts the current elevation value of each calculation point; determines the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point; generates the target terrain raster data based on the design elevation value, determines the intersection of the main road and the secondary road through the road traffic data, takes the intersection as the control point of the urban vertical planning, and determines the control elevation value of the control point through the target terrain raster data. After obtaining the geospatial data of the research scope, this application first pre-processes the data, deducts the areas that cannot reflect the real terrain, and improves the calculation accuracy; through detailed analysis of the terrain slope zoning and rainwater discharge path, it can more accurately determine the flow direction and accumulation area of ​​rainwater, and can more accurately determine the vertical elevation requirements of different areas. Compared with the traditional vertical planning method that is limited to point data, this application generates two-dimensional surface data based on the calculated design elevation value, avoiding the problem of relatively low-lying local areas, and can provide an accurate basis for the lower-level vertical planning. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A schematic diagram of a flow chart of a vertical elevation calculation method for a megacity provided in one embodiment of the present application;

[0060] Figure 2 A schematic diagram of the structure of a vertical elevation calculation device for a megacity provided in one embodiment of the present application;

[0061] Figure 3 A schematic diagram of the structure of a vertical elevation calculation device for a megacity provided by another embodiment of the present application;

[0062] Description of reference numerals:

[0063] Data acquisition module-01, data analysis module-02, current elevation extraction module-03, design elevation determination module-04, control elevation calculation module-05. DETAILED DESCRIPTION

[0064] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0066] In addition, the term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application, unless otherwise specified, generally indicates that the associated objects before and after are in an "or" relationship.

[0067] In this application, the terms "first", "second", etc. are used to distinguish identical or similar items with basically the same effects and functions. It should be understood that there is no logical or temporal dependency between "first", "second", and "nth", nor is there any limitation on quantity and execution order.

[0068] The following is a further detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The vertical elevation calculation method proposed in the present application is applicable to the vertical planning of a super-large-scale city, where a super-large-scale city refers to a city that includes multiple urban districts, counties or larger areas. Figure 1 As shown, the vertical elevation calculation method for a megacity provided in this application includes the following steps:

[0069] S10: Acquire the geospatial data of the research scope, preprocess the geospatial data, and obtain the preprocessed geospatial data; wherein the geospatial data includes terrain data, river system data, road traffic data, and rainwater pipe network data.

[0070] Among them, the terrain data is the terrain raster data of the research scope, and the resolution of the terrain raster data is 2m×2m, which can be obtained through aerial photogrammetry, satellite remote sensing, ground laser scanning and other means; the river system data is the river system surface data composed of river system embankments under the current situation; the road traffic data includes elevated road distribution surface data, bridge distribution surface data and urban road distribution data, as well as information such as road width and grade; the rainwater pipe network data includes drainage pipe discharge direction data, discharge outlet distribution data, and discharge outlet water level data.

[0071] S20: Analyze the preprocessed geographic spatial data to obtain watershed division results and slope analysis results, convert the raster map into slope vector surface data based on the slope analysis results, and then analyze the watershed division results based on the slope vector surface data to obtain the slope type of each watershed division.

[0072] Specifically, the spatial analysis toolbox of ArcGIS geographic information system provides a series of spatial analysis functions. ArcGIS can be used to effectively process geospatial data, perform hydrological analysis and slope analysis, and record the slope analysis results obtained from the slope analysis as "SLOPE", and the watershed division results obtained from the hydrological analysis as "JSFQ".

[0073] S30: Based on the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment area, the rainwater discharge path of each catchment area is drawn, the calculation points of the vertical elevation are determined based on the rainwater discharge path, and the current elevation value of each calculation point is extracted.

[0074] Specifically, the slope type of each catchment area is determined based on the slope vector surface data. Different slope types reflect different characteristics of the terrain. For different types of catchment areas, the calculation points of the vertical elevations are determined differently, and the current elevation values ​​of each calculation point are extracted to ensure that the vertical design conforms to the natural terrain and can achieve efficient drainage.

[0075] S40: Determine the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point.

[0076] This application considers the design elevation value of the calculation point for calculating the vertical elevation, taking into account the rainwater surface runoff, and at the same time increases the comparison with the current elevation value. When the current elevation value can meet the minimum requirement for rainwater surface runoff, the vertical elevation calculation point is regarded as the current limiting factor, and the current elevation value is maintained unchanged. In addition, this application standardizes the calculation process of the vertical elevation calculation point, providing a basis for the dynamic update of planning data.

[0077] S50: Generate target terrain raster data based on the design elevation value, determine the intersections of main roads and secondary roads through road traffic data, use the intersections as control points for the city's vertical master plan, and determine the control elevation values ​​of the control points through the target terrain raster data.

[0078] Compared with the traditional vertical planning method which is limited to the calculation of vertical elevations of road intersections, this application generates two-dimensional DEM data from the calculated vertical elevation calculation points, converts the traditional one-dimensional point data of vertical planning into two-dimensional surface data, and then performs depression filling processing, which solves the problem of relatively low-lying areas in some areas. Identifying and extracting the intersections of main roads and secondary roads as vertical planning control points, and assigning elevation values ​​to control points can provide accurate calculation basis for the lower-level vertical detailed vertical planning, solving the problem of inconsistent calculation basis for the elevation of the lower-level vertical planning.

[0079] In some embodiments, step S10 obtains the geospatial data of the research scope, preprocesses the geospatial data, and obtains the preprocessed geospatial data, specifically including: obtaining the shapefile data of terrain data, river system data, road traffic data, and rainwater pipe network data in the same geographic coordinate system within the research scope; using the erase tool in the ArcGIS analysis toolbox to erase the elevated bridge surface and river system surface data in the road traffic data from the terrain data, and using the difference method to regenerate the geospatial data of the research scope; combining the rainwater discharge direction, determining the starting point and end point of the rainwater pipe network vector line from the rainwater pipe network data, wherein the starting point of the rainwater pipe network vector line is set to the discharge port of the rainwater pipe network, and the end point of the rainwater pipe network vector line is set to the starting point of the rainwater pipe network. It should be noted that the discharge port is the outlet where rainwater is finally discharged from the rainwater pipe network system. Usually, these outlets are located at the downstream end of the pipe network and connected to natural water bodies (such as rivers, lakes, oceans) or artificial drainage facilities (such as drainage ditches, reservoirs); the starting point of the rainwater pipe network is the entrance where rainwater begins to enter the pipe network. These starting points can be rainwater inlets, rainwater wells or other collection facilities. In the actual implementation process, it was found that the water system and the viaduct pavement cannot reflect the actual ground elevation, which will affect the calculation results. Erasing the water system and the viaduct pavement is to improve the accuracy of subsequent elevation calculations.

[0080] In some embodiments, in step S20, the pre-processed geographic spatial data is analyzed to obtain watershed partition results and slope analysis results, and the raster map is converted into slope vector surface data based on the slope analysis results, and then the watershed partition results are analyzed based on the slope vector surface data to obtain the slope type of each watershed partition, specifically including:

[0081] The hydrological analysis tool in ArcGIS was used to perform depression filling, watershed area and flow direction analysis on the terrain data of the preprocessed geospatial data to determine the rainwater catchment zone, which was named "JSFQ". The slope analysis in the surface analysis tool in ArcGIS was used to analyze the terrain data of the preprocessed geospatial data, and the slope analysis result with the measurement unit of PERCENT_RISE was output, named "SLOPE". The slope analysis result was converted into integer slope data, and the integer slope data was converted into slope vector surface data through the raster to surface tool in ArcGIS. Specifically, the "SLOPE" data was multiplied by 10 to generate "SLOPE_t ime10" data, convert "SLOPE_time10" data to integer, output "INT_SLOPE_time10" data, convert "INT_SLOPE_time10" data to surface data through the raster to surface tool, the field is the raster value "value", and obtain the terrain slope surface data after the terrain slope value is magnified 10 times, named "XZDXPD", which is the current terrain slope, add the field "SLOPE" to the "XZDXPD" vertical table, use the field calculator tool, the formula is "SLOPE = [value]", that is, get the slope vector surface data with the current terrain slope attribute, the unit is ‰. Based on the slope vector surface data, the research scope is divided into plain area, gentle slope area and steep slope area; obtain the slope vector surface data of each rainwater catchment zone, analyze the proportion of plain area, gentle slope area and steep slope area in the rainwater catchment zone, and obtain the slope type of the rainwater catchment zone. Specifically, the rainwater zoning result "JSFQ" (rainwater catchment zone) is used as the input element, and the slope zoning result is used as the identification element. The proportion of each slope zone area in each rainwater catchment zone is counted. When the proportion of a certain slope zone area is greater than 80%, the rainwater zone can be regarded as the terrain area. For example, when 85% of the area in the rainwater catchment zone JSFQ-1 belongs to the gentle slope area, 5% belongs to the plain area, and 10% belongs to the steep slope area, the slope type of the rainwater catchment zone JSFQ-1 is the gentle slope area.

[0082] The steps of dividing the research scope into plain area, gentle slope area and steep slope area include: when the slope vector surface data is between 0 and 0.003, the corresponding area is determined to be a plain area; when the slope vector surface data is between 0.003 and 0.03, the corresponding area is determined to be a gentle slope area; when the slope vector surface data is greater than 0.03, the corresponding area is determined to be a steep slope area. In the actual implementation process, the attribute selection tool in ArcGIS is used to divide the terrain slope in the slope vector surface data into areas between 0 and 0.003, 0.003 and 0.03 or more.

[0083] For rainwater catchment zones with different slope types, differential classification calculations can be performed. The calculation targets for vertical elevations are as follows:

[0084] For plain areas, vertical planning should be based on the principle of meeting rainwater discharge requirements to ensure that the overall terrain slopes towards the rainwater discharge area with a slope of not less than 0.001; for gently sloping areas, the existing terrain can basically meet the rainwater discharge requirements, and vertical planning should strengthen the connection with the existing area to avoid local low-lying areas; for steep slope areas, due to the steep slope of the terrain, rainwater discharge is no longer the main limiting factor, and vertical planning should focus on maintaining the status quo while meeting reasonable planning under the requirements of road design.

[0085] After obtaining the slope type of the rainwater catchment zone, the rainwater discharge path is drawn in combination with the river system distribution, road traffic distribution, rainwater pipe network, etc. in each rainwater catchment zone, named "YSJL", that is, rainwater runoff, and numbered. At the same time, the drawing principles of rainwater discharge paths of various slope types are as follows: for rainwater catchment zones in plain areas, the terrain slope is less than 0.003, and the hydrological analysis results are difficult to reflect the actual rainwater collection. The vertical planning should be aimed at satisfying the reasonable discharge of rainwater in the area. It should be based on the distribution of the rainwater pipe network, and the vector line data of the rainwater discharge path in each zone should be drawn against the drainage direction with the rainwater discharge outlet as the starting point; for rainwater catchment zones in gentle slope areas, the terrain slope is between 0.003 and 0.03, and the regional rainwater can basically meet the natural discharge conditions. The vertical planning should be based on the hydrological analysis results, combined with the distribution of traffic roads and river systems, to draw the vector line data of the rainwater discharge path in each zone; for rainwater catchment zones in steep slope areas, the terrain slope is greater than 0.03, and the regional rainwater discharge conditions are good, basically maintaining the status quo.

[0086] In some embodiments, in step S30, the steps of determining the calculation points of the vertical elevation based on the rainwater discharge path and extracting the current elevation value of each calculation point include:

[0087] The point-generating tool along the line in ArcGIS is used to generate a calculation point every 50m along the rainwater discharge path, and the starting point to the end point are numbered from small to large; the sampling tool in the extraction analysis in ArcGIS is used to extract the current elevation value of each calculation point. In the actual implementation process, the point-generating tool along the line in the sampling tool in ArcGIS is used to generate vertical elevation calculation points along the rainwater discharge path at a distance of 50m, including the end point. During this operation, the points generated by the same runoff path have the same number in the previous step, and the "OBJECTID" field in the point data attribute table is automatically sorted from small to large from the starting point to the end point; the sampling tool in the extraction analysis in ArcGIS is used to extract the current elevation value according to the generated vertical elevation calculation point in the current terrain raster data, and the current elevation value is named "RASTERVALU", and the "XZBG" field is created. The "RASTERVALU" value is assigned to the "XZBG" field, and the X and Y fields with horizontal and vertical coordinate attributes are added, and the coordinate values ​​are assigned to the X and Y fields respectively.

[0088] In some embodiments, in step S40, the steps of determining the design elevation values ​​of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point include: using the identification tool in ArcGIS, taking the calculation point of the vertical elevation as input data, and taking the urban space attribute as the identification item, generating vertical elevation calculation points with spatial attributes, assigning the attribute field belonging to the built-up area to 1, and assigning the attribute field not belonging to the built-up area to 0; exporting the vertical elevation calculation points with spatial attributes to an excel file, and filtering the data in the excel file through Python; reading the first value in the object column in the excel file, and subtracting the first value from each value in the object column and assigning it to the number column and numbering it from 0; creating a height difference column, multiplying the value of the number column by 0.05 and assigning it to the height difference column; creating a discharge outlet elevation, and assigning the corresponding elevation value of the number column numbered 0 to the discharge outlet elevation; creating a calculation elevation column and a design elevation column, and determining the design elevation value of the calculation point row by row according to preset rules.

[0089] Specifically, the identification tool in ArcGIS is used, with the calculation points of vertical elevation as input elements, and the urban space attributes of built-up areas and non-built-up areas as identification elements, to generate calculation points of vertical elevation with urban space attributes, and add fields "JCQ" (built-up area) and "FJCQ" (non-built-up area). The "JCQ" field corresponding to the calculation points in the built-up area is assigned a value of "1", otherwise the "JCQ" field corresponding to the calculation points in the non-built-up area is assigned a value of "0"; the attribute table of the calculation points of the vertical elevation with complete attribute information is exported to an excel file, and the "pandas" table reading and processing module in Python is used to filter the data according to the number of each rainwater discharge path, and create a separate sheet Table; read the first number in the "OBJECTID" column of each sheet, and subtract the first number from each value in "OBJECTID" and assign it to a new column "BH", i.e., the number. The value "0" indicates that the point is a rainwater pipe discharge outlet, and the number value of the calculation point increases in the opposite direction of rainwater discharge; create a new column "GC", i.e., height difference, and assign the value "BH" × 0.05 to the column "GC", and the column "GC" indicates the minimum height difference requirement from the calculation point to the rainwater discharge point; create a new column "PFKBG", i.e., the discharge outlet elevation, and assign the value "XZBG" in the first row "BH" = 0 to the column; create new columns "JSBG" and "SJBG", i.e., the calculated elevation and the designed elevation, and calculate the calculated elevation value and the designed elevation value row by row according to the number sorting.

[0090] The step of determining the design elevation values ​​of the calculation points row by row according to the preset rules includes:

[0091] When the calculated elevation value is less than the current elevation value and the space attribute is 1, the design elevation value is equal to the current elevation value;

[0092] When the calculated elevation value is less than the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value;

[0093] When the calculated elevation value is greater than or equal to the current elevation value, and the space attribute is 1, the design elevation value is equal to the calculated elevation value;

[0094] When the calculated elevation value is greater than or equal to the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value.

[0095] 1) For the first row "BH" = 0, that is, at the rainwater discharge outlet, it is generally the elevation of the road along the river or the river bank elevation, and the current elevation is maintained. Let "JSBG" = "XZBG" = "SJBG", that is, the calculated elevation value is equal to the current elevation value and equal to the design elevation value;

[0096] 2) For "BH" = 1, the "JSBG" value is equal to the "SJBG" of the previous row, i.e. "BH" = 0, plus the height difference of 0.05m. The design elevation value of this row needs to be judged according to the following judgment conditions:

[0097] ① Judgment condition 1:

[0098] If "JSBG"<"XZBG", and "JCQ"=1;

[0099] Then "SJBG" = "XZBG".

[0100] ② Judgment condition 2:

[0101] If "JSBG"<"XZBG", and "JCQ"=0;

[0102] Then "SJBG" = "JSBG".

[0103] ③ Judgment condition three:

[0104] If "JSBG" ≥ "XZBG", and "JCQ" = 1;

[0105] Then "SJBG" = "JSBG".

[0106] ④ Judgment condition four:

[0107] If "JSBG" ≥ "XZBG", and "JCQ" = 0;

[0108] Then "SJBG" = "JSBG".

[0109] 3) For "BH" = 2, the above process flow is looped.

[0110] In some embodiments, step S50 specifically includes: using the triangle mesh method in ArcGIS to generate target terrain raster data based on the design elevation value of the calculation point, and performing depression filling preprocessing on the target terrain raster data;

[0111] Extract the intersections of main roads and secondary roads from road traffic data as control points for urban vertical planning within the research scope;

[0112] The design elevation values ​​corresponding to the control points are extracted from the target terrain raster data after the preprocessing of the filling process as the control elevation values ​​of the control points, which are used to guide the vertical planning of the city.

[0113] The technical solution proposed in this application solves the problem that the original technical method is not generally applicable to super-large cities with complex and diverse terrains. At the same time, due to the large number of restrictive factors in the original technical method, it is difficult to apply it to the calculation of large-scale vertical elevations in the city. This application mainly provides a vertical planning elevation calculation method that can ensure the bottom line of regional flood safety within a large-scale urban area. Compared with the original vertical planning method that is limited to the calculation of vertical elevations at road intersections, this application is based on hydrological analysis, comprehensively considers limiting factors such as rainwater surface runoff and existing construction, and finely calculates the elevation along the rainwater runoff line, converts traditional vertical planning point data into two-dimensional surface data, and then fills the depression, which solves the problem of relatively low-lying areas in some areas and realizes the transformation of vertical planning from one-dimensional control to two-dimensional plane control. Finally, the intersections of main roads and secondary roads are identified and extracted as vertical planning control points, and the elevation values ​​are assigned to the control points, providing a calculation basis for the preparation of the lower-level vertical detailed planning, solving the problem of inconsistent calculation basis for the lower-level vertical planning elevation.

[0114] Another embodiment of the present application also provides a vertical elevation calculation device for a megacity, the calculation device is used to execute the above calculation method, such as Figure 2 As shown, the computing device includes:

[0115] Data acquisition module 01 is used to acquire geographic spatial data within the research scope, pre-process the geographic spatial data, and obtain pre-processed geographic spatial data; wherein the geographic spatial data includes terrain data, river system data, road traffic data, and rainwater pipe network data;

[0116] Data analysis module 02 is used to analyze the pre-processed geographic spatial data to obtain watershed partition results and slope analysis results, convert the raster map into slope vector surface data based on the slope analysis results, and then analyze the watershed partition results based on the slope vector surface data to obtain the slope type of each watershed partition;

[0117] The current elevation extraction module 03 is used to draw the rainwater discharge path of each catchment zone according to the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment zone, determine the calculation points of the vertical elevation based on the rainwater discharge path, and extract the current elevation value of each calculation point;

[0118] Design elevation determination module 04, used to determine the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point;

[0119] The control elevation calculation module 05 is used to generate target terrain grid data based on the design elevation value, determine the intersections of main roads and secondary roads through road traffic data, use the intersections as control points for the city's vertical master plan, and determine the control elevation values ​​of the control points through the target terrain grid data.

[0120] The specific definition of a vertical elevation calculation device for a megacity provided in this embodiment can be found in the embodiment of the vertical elevation calculation method for a megacity described above, and will not be repeated here. Each module in the vertical elevation calculation device for a megacity described above can be implemented in whole or in part by software, hardware, and a combination thereof. Each of the above modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each of the above modules.

[0121] In some embodiments, Figure 3 As shown, an embodiment of the present application also provides a vertical elevation calculation device for a megacity, which may include a processor, a memory, a network interface, and a database connected via a system bus. The processor of the computing device is used to provide computing and control capabilities. The memory of the computing device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computing device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, the processor executes the steps of the vertical elevation calculation method for a megacity as in any of the above embodiments.

[0122] The working process, working details and technical effects of the computer equipment provided in this embodiment can be found in the above embodiment of the vertical elevation calculation method for super-large cities, and will not be described in detail here.

[0123] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0124] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0125] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the system described in the present application is divided into different functional units or modules to complete all or part of the functions described above.

Claims

1. A method for calculating vertical elevation of a megacity, characterized in that: include: Acquire geospatial data within the research scope, preprocess the geospatial data, and obtain preprocessed geospatial data; The geospatial data include terrain data, river system data, road traffic data and rainwater pipe network data; Analyze the preprocessed geospatial data to obtain the watershed division results and slope analysis results. Based on the slope analysis results, convert the raster map into slope vector surface data. Then, analyze the watershed division results based on the slope vector surface data to obtain the slope type of each watershed division. Based on the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment area, the rainwater discharge path of each catchment area is drawn, the calculation points of the vertical elevation are determined based on the rainwater discharge path, and the current elevation value of each calculation point is extracted; According to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point, determine the design elevation value of each calculation point along the rainwater discharge path; The target terrain grid data is generated based on the design elevation value, the intersections of the main roads and the secondary roads are determined through the road traffic data, the intersections are used as control points of the urban vertical master plan, and the control elevation values ​​of the control points are determined through the target terrain grid data.

2. The vertical elevation calculation method for a megacity according to claim 1, characterized in that: The obtaining of the geospatial data within the research scope and preprocessing the geospatial data to obtain the preprocessed geospatial data includes: Obtain terrain data, river system data, road traffic data and rainwater pipe network data in the same geographic coordinate system within the research scope; Erasing the elevated bridge surface and river system surface data in the road traffic data from the terrain data, and using the difference method to regenerate the terrain data within the research scope; The starting point and the end point of the rainwater pipe network vector line are determined from the rainwater pipe network data, wherein the starting point of the rainwater pipe network vector line is set as the discharge outlet of the rainwater pipe network, and the end point of the rainwater pipe network vector line is set as the starting point of the rainwater pipe network.

3. The vertical elevation calculation method for a megacity according to claim 2, characterized in that: The pre-processed geospatial data is analyzed to obtain the watershed division results and slope analysis results. The raster map is converted into slope vector surface data based on the slope analysis results. The watershed division results are then analyzed based on the slope vector surface data to obtain the slope types of each watershed division, including: The hydrological analysis tools in ArcGIS were used to perform depression filling, water collection analysis and flow direction analysis on the pre-processed geospatial data to determine the rainwater catchment zones. Use the surface analysis tool in ArcGIS to perform slope analysis on the preprocessed geospatial data and output the slope analysis results; The slope analysis results are converted into integer slope data, and the integer slope data is converted into slope vector surface data through the raster to surface tool in ArcGIS. Based on the slope vector surface data, the research area is divided into plain area, gentle slope area and steep slope area; The slope vector surface data of each rainwater catchment zone is obtained, and the proportion of plain area, gentle slope area and steep slope area in the rainwater catchment zone is analyzed to obtain the slope type of the rainwater catchment zone.

4. The vertical elevation calculation method for a megacity according to claim 3 is characterized in that: Based on the slope vector surface data, the research area is divided into plain area, gentle slope area and steep slope area, including: When the slope vector surface data is between 0 and 0.003, the corresponding research range is determined to be a plain area; When the slope vector surface data is between 0.003 and 0.03, the corresponding research range is determined to be a gentle slope area; When the slope vector surface data is greater than 0.03, the corresponding research range is determined to be a steep slope area.

5. The vertical elevation calculation method for a megacity according to claim 1, characterized in that: Determine the calculation points of vertical elevation based on the rainwater discharge path, and extract the current elevation values ​​of each calculation point, including: Use the Generate Points Along Line tool in ArcGIS to generate a calculation point every 50 meters along the stormwater drainage path, and number the starting point to the end point from small to large; The sampling tool in ArcGIS was used to extract the current elevation value of each calculation point.

6. The vertical elevation calculation method for a megacity according to claim 1, characterized in that: The method of determining the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point includes: Using the identification tool in ArcGIS, the calculation point of vertical elevation is used as input data, and the urban spatial attribute is used as the identification item to generate the vertical elevation calculation point with spatial attributes. The attribute field belonging to the built-up area is assigned to 1, and the attribute field not belonging to the built-up area is assigned to 0. Export the vertical elevation calculation points with spatial attributes to an Excel file, and filter the data in the Excel file using Python; Read the first value in the object column in the Excel file, subtract the first value from each value in the object column and assign them to the number column starting from 0; Create a height difference column, multiply the value of the number column by 0.05 and assign it to the height difference column; Create the discharge outlet elevation, and assign the corresponding elevation value of the number column numbered 0 to the discharge outlet elevation; Create calculated elevation columns and design elevation columns, and determine the calculated elevation values ​​and design elevation values ​​of the calculation points row by row according to preset rules.

7. The vertical elevation calculation method for a megacity according to claim 6, characterized in that: Determine the design elevation values ​​of the calculation points row by row according to the preset rules, including: When the calculated elevation value is less than the current elevation value and the space attribute is 1, the design elevation value is equal to the current elevation value; When the calculated elevation value is less than the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value; When the calculated elevation value is greater than or equal to the current elevation value, and the space attribute is 1, the design elevation value is equal to the calculated elevation value; When the calculated elevation value is greater than or equal to the current elevation value and the space attribute is 0, the design elevation value is equal to the calculated elevation value.

8. The vertical elevation calculation method for a megacity according to claim 1, characterized in that: The method of generating target terrain grid data based on the design elevation value, determining the intersection of the main road and the secondary road through the road traffic data, using the intersection as the control point of the urban vertical master plan, and determining the control elevation value of the control point through the target terrain grid data includes: The target terrain raster data is generated based on the design elevation value of the calculation point using the triangle grid method in ArcGIS, and the target terrain raster data is preprocessed for filling depressions. Extract the intersections of main roads and secondary roads from road traffic data as control points for urban vertical planning within the research scope; The design elevation values ​​corresponding to the control points are extracted from the target terrain raster data after the preprocessing of the filling process as the control elevation values ​​of the control points, which are used to guide the vertical planning of the city.

9. A vertical elevation calculation device for a megacity, characterized in that: Used to perform the method according to any one of claims 1 to 8, comprising: A data acquisition module is used to acquire geospatial data within the research scope, preprocess the geospatial data, and obtain preprocessed geospatial data; wherein the geospatial data includes terrain data, river system data, road traffic data, and rainwater pipe network data; The data analysis module is used to analyze the pre-processed geographic spatial data to obtain the watershed partition results and slope analysis results, convert the raster map into slope vector surface data based on the slope analysis results, and then analyze the watershed partition results based on the slope vector surface data to obtain the slope type of each watershed partition; The current elevation extraction module is used to draw the rainwater discharge path of each catchment zone according to the slope vector surface data, combined with the slope type, river system data and road traffic data of each catchment zone, determine the calculation points of the vertical elevation based on the rainwater discharge path, and extract the current elevation value of each calculation point; A design elevation determination module is used to determine the design elevation value of each calculation point along the rainwater discharge path according to the discharge outlet elevation value of the rainwater discharge outlet and the current elevation value of the calculation point; The control elevation calculation module is used to generate target terrain grid data based on the design elevation value, determine the intersection of the main road and the secondary road through road traffic data, use the intersection as the control point of the urban vertical master plan, and determine the control elevation value of the control point through the target terrain grid data.

10. A vertical elevation calculation device for a megacity, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 8.

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