Standard number: GB/T 35637-2017
Standard name: Basic technical requirements for urban surveying
and mapping English name: Basic technical requirements for urban surveying and mapping
Standard format: PDF
Release time: 2017-12-29
Implementation time: 2018-07-01
Standard size: 13.3M
Standard introduction: This standard specifies the overall requirements for urban surveying and mapping, as well as the basic requirements for basic control measurement, geographic information data acquisition, special surveying and mapping, geographic information data management and application, and quality control.
This standard applies to the technical design, operation implementation and quality management of urban surveying and mapping.
2 Normative reference documents
The following documents are indispensable for the application of this document. For all referenced documents with dates, only the versions with dates apply to this document. For any undated referenced documents, the latest version (including all amendments) applies to this document
GB/T13923 Basic geographic information element classification and code
GB/T17796 Administrative area boundary surveying and mapping specifications
GB/T17798 Geospatial data exchange format
GB/T17986.1 Property measurement specifications Unit 1: Property measurement regulations
GB/T18316 Quality inspection and acceptance of digital surveying and mapping results
GB/T20257.1 National basic scale map diagram Part 1: 1:500 1:1000 1:2000 Topographic map diagram GB/T20257.2 National basic scale map diagram Part 2 Part: 1:50001:10000 Topographic map format
GB/T20258.1 Basic geographic information element data dictionary Part 1: 1:5001:10001:2000 Basic geographic information element data dictionary
GB/T20258.2 Basic geographic information element data dictionary Part 2: 1:50001:10000 Basic geographic information element data dictionary
GB/T24356 Quality inspection and acceptance of surveying and mapping results
GB/T30318 Basic provisions of geographic information public platform
GB/T35636 Specification for urban underground space surveying and mapping This standard is drafted in accordance with the rules given in GB/T1.1-2009.
This standard is proposed by the State Administration of Surveying, Mapping and Geoinformation.
This standard is under the jurisdiction of the National Technical Committee for Geographic Information Standardization (SAC/TC230). Drafting units of this standard: Construction Comprehensive Survey Research and Design Institute Co., Ltd., Beijing Surveying and Mapping Design Institute, China Surveying and Mapping Research
Institute, Chongqing Surveying Institute, Guangzhou Urban Planning Survey and Design Institute, Surveying and Mapping Standardization Institute of the State Administration of Surveying, Mapping and Geoinformation, Shenzhen Construction
Comprehensive Survey and Design Institute Co., Ltd., Nanjing Surveying and Mapping Research Institute Co., Ltd., Wuhan Surveying and Mapping Research Institute, Harbin Surveying and Mapping Research Institute, Jinan Surveying and Mapping Research Institute, Tianjin Surveying Institute, Qingdao Surveying and Mapping Research Institute
Main drafters of this standard: Wang Dan, Yang Bogang, Li Chengming, Xie Zhenghai, Lin Hong, Geng Dan, Zhang Kun, Wang Shuanglong, Jia Guangjun, Wang Shudong, Chu Zhengwei, Wang Houzhi, Hu Yaming, Niu Shouming, Huang Enxing, Zhao Yabo, Yang Yongxing, Li Hua
This standard specifies the overall requirements for urban surveying and mapping, as well as the basic requirements for basic control measurement, geographic information data acquisition, special surveying and mapping, geographic information data management and application, and quality control. This standard applies to the technical design, operation implementation and quality management of urban surveying and mapping.

ICS07.040
YrrKAa~cJouaKAa
National Standard of the People's Republic of China
GB/T35637—2017
Basic technical requirements for urban surveying and mapping
Basic technical requirements for urban surveying and mapping2017-12-29Issued
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of ChinaStandardization Administration of the People's Republic of China
2018-07-01Implementation
YTrKAa-cJouaKAa-
Normative reference documents
Terms and definitions
Abbreviations
Overall requirements
Spatial-temporal benchmark
Accuracy indicators
Instruments and software
Implementation process
Basic control measurement
General provisions
Plane coordinate system
Plane control network
Elevation control network
Quasi-geoid refinement
Geographic information data acquisition
General provisions
Digital line drawing data
TTKAcJouaKAa=
Digital orthophoto and digital true orthophoto dataDigital elevation model and digital surface model dataNew image and point cloud data
Three-dimensional city model data
Thematic geographic information data
Special surveying and mapping
General provisions| |tt||Engineering surveying and mapping
Underground space surveying and mapping
Real estate surveying and mapping
Administrative boundary surveying and mapping
Map compilation:
Geographic national conditions census and monitoring
Other surveys and surveys
Geographic information data management and application:
General provisions
GB/T35637—2017
GB/T35637—2017
Geographic information database
Geographic information public platform.
Geographic information application system
Quality Control
General provisions
Quality inspection of results
System test evaluation
References
TiKAa-cJouaKAa
..............
...........
....................
..............
TrrKAa~cJouaKAa
This standard was drafted in accordance with the rules given in GB/T1.1-2009. This standard was proposed by the State Administration of Surveying, Mapping and Geoinformation. This standard is under the jurisdiction of the National Technical Committee for Geographic Information Standardization (SAC/TC230). GB/T35637-—2017
Drafting units of this standard: Construction Comprehensive Survey Research and Design Institute Co., Ltd., Beijing Surveying and Mapping Design Institute, China Academy of Surveying and Mapping, Chongqing Surveying Institute, Guangzhou Urban Planning Survey and Design Institute, Surveying and Mapping Standardization Institute of the State Administration of Surveying, Mapping and Geoinformation, Shenzhen Construction Comprehensive Survey and Design Institute Co., Ltd., Nanjing Surveying and Mapping Research Institute Co., Ltd., Wuhan Surveying and Mapping Research Institute, Harbin Surveying and Mapping Research Institute, Jinan Surveying and Mapping Research Institute, Tianjin Surveying Institute, Qingdao Surveying and Mapping Research Institute The main drafters of this standard: Wang Dan, Yang Bogang, Li Chengming, Xie Zhenghai, Lin Hong, Geng Dan, Zhang Kun, Wang Shuanglong, Jia Guangjun, Wang Shudong, Chu Zhengwei, Wang Houzhi, Hu Yaming, Niu Shouming, Huang Enxing, Zhao Yabo, Yang Yong Xing, Li Hua GB/T35637—2017
YirKAacouakAa
In order to standardize urban surveying and mapping work and better meet the needs of economic construction and social development, this standard is formulated in accordance with the "Surveying and Mapping Law of the People's Republic of China", "Urban and Rural Planning Law of the People's Republic of China", "Regulations on the Management of Surveying and Mapping Results of the People's Republic of China", "Basic Surveying and Mapping Regulations" and "Map Management Regulations" and other laws and regulations and current relevant national standards, combined with the current urban surveying and mapping production practice and related technical development in my country. Urban surveying and mapping referred to in this standard refers to surveying and mapping geographic information activities that guarantee and serve urban planning, construction and management, mainly including basic control measurement, geographic information data acquisition, special surveying and mapping, geographic information data management and application, and quality control. The city here includes small towns; special surveying and mapping generally refers to other urban surveying and mapping work except basic control measurement, geographic information data acquisition, geographic information data management and application.
1 Scope
TTrKA-cJouaKAa-
Basic Technical Requirements for Urban Surveying and Mapping
GB/T35637-—2017
This standard specifies the overall requirements for urban surveying and mapping, as well as the basic requirements for basic control measurement, geographic information data acquisition, special surveying and mapping, geographic information data management and application, and quality control. This standard applies to the technical design, operation implementation and quality management of urban surveying and mapping. Normative References
The following documents are indispensable for the application of this document. For all dated references, only the dated version applies to this document. For any undated referenced documents, the latest version (including all amendments) shall apply to this document GB/T13923
GB/T17796
GB/T17798
GB/T17986.1
GB/T18316
GB/T20257.1
Classification and Codes of Basic Geographic Information Elements
Measurement of Administrative Boundaries Drawing specification
Geospatial data exchange format
Property measurement specification Unit 1: Property measurement regulations Digital surveying and mapping results quality inspection and acceptance
National basic scale map format
GB/T20257.2
GB/T20258.1
Feature data dictionary
GB/T20258.2
Data dictionary
GB/ T24356
GB/T30318
GB/T35636
Part 1: 1:5001:10001:2000 Topographic map patterns National basic scale map patterns Part 2: 1:50001:10000 Topographic map patterns Basic geographic information element data dictionary
Basic geographic information element data dictionary
Quality inspection and acceptance of surveying and mapping results||tt ||Basic provisions of geographic information public platform
Specifications for urban underground space surveying and mapping
Specifications for engineering surveying
GB50026
CJJ/T8 specifications for urban surveying
TD/T1001
Terms and definitions
Cadastral survey procedures
The following terms and definitions apply to this document. 3.1
Urban surveying and mapping
Urban surveying and mapping
Part 1: 1:50001:100001:2000 Basic geographic information Part 2: 1:50001:10000 Basic geographic information elements Surveying and mapping geographic information activities that support and serve urban planning, construction and management. 3.2
Digital true-orthophotoimages
digital true-orthophotoimages are digital orthophotos that use digital surface models to geometrically process image data and eliminate projection errors caused by terrain and artificial objects.
GB/T35637—2017
TrKAa-cJouaKAa-
obliquephotographicimages
Obliquephotographicimages
Multi-view images obtained using oblique mathematical aerial cameras, generally including a bird's-eye view image and multiple side-view images. 3.4
Measurable real-scene images
digital measurableimages
Ground digital images with positioning and attitude parameters and time parameters obtained using mobile measurement technology. 3.5
fpublic platform of geographic information Public platform of geographic information
A general term for data, software and supporting environment that provide public services of geographic information such as geographic information system construction, spatial positioning, spatial analysis and other applications for government departments, enterprises, institutions or the public Note: The service modes of the public platform of geographic information include online calling, server hosting and offline services. 4 Abbreviations
The following abbreviations apply to this document
BIM Building Information Modeling CAD Computer Aided Design GIS Geographic Information System GNSS Global Navigation Satellite System LOD Level of Detail
5 General requirements
Spatiotemporal benchmark
5.1.1 The plane coordinate system of urban surveying and mapping adopts the 2000 National Geodetic Coordinate System: When it is necessary to adopt other relatively independent plane coordinate systems, they should be linked to the 2000 National Geodetic Coordinate System. 5.1.2 The elevation system of urban surveying and mapping adopts the normal height system, and the elevation benchmark adopts the 1985 national elevation benchmark: when it is necessary to adopt other elevation benchmarks, they should be linked to the 1985 national elevation benchmark. 5.1.3 The gravity benchmark of urban surveying and mapping adopts the national gravity benchmark embodied by the 2000 National Gravity Basic Network. 5.1.4 The depth benchmark of urban surveying and mapping adopts the theoretical lowest tide surface in coastal waters and the design water level in inland waters. The depth benchmark and the national elevation benchmark are linked through the leveling joint survey of tide gauge stations. 5.1.5 The date of urban surveying and mapping adopts the Gregorian calendar and the time adopts Beijing time. 5.1.6 When urban surveying and mapping involves coastal waters, land and sea surveying and mapping should adopt a unified time and space benchmark. The surveying and mapping of the same city should adopt a unified time and space benchmark. 5.1.7
Accuracy index
Urban surveying and mapping adopts the mean error as the technical index of accuracy, and 2 times the mean error as the limit error. 5.3
Instruments and equipment and software
5.3.1 The instruments and equipment used in urban surveying and mapping that need to be calibrated shall be qualified by the calibration agency recognized by the competent department and used within the validity period of the calibration: other instruments and equipment shall be inspected and calibrated according to the requirements of their instruction manuals. 5.3.2 The instruments and equipment used in urban surveying and mapping shall be used under the operating conditions given in their instruction manuals and be in normal condition. During the operation, the necessary inspection and calibration of the instruments and equipment shall be carried out in a timely manner according to the requirements of relevant standards and changes in operating conditions. When the instruments and equipment are abnormal, they shall be inspected and calibrated or repaired and calibrated in a timely manner GB/T35637—2017
5.3.3 The software used in urban surveying and mapping shall be tested and verified by a third party or the user unit, and the relevant documents and data of the test and verification shall be retained. 5.4 Implementation process
Urban surveying and mapping and its results shall comply with the requirements of national laws and regulations and mandatory national standards. 5.4.1
5.4.2 Before the implementation of urban surveying and mapping, data should be collected, and on-site investigation and technical design should be carried out according to the task requirements. The technical design should meet the following requirements:
The name and number of the standard adopted by the project should be clearly stated: In addition to following this standard, the basic standards related to data description and definition, quality control, etc. should adopt the current national standards, and b)
can be expanded according to the rules given in the corresponding national standards according to the special circumstances of the city: c
The specific surveying and mapping content, accuracy requirements, technical methods, results form, metadata files, etc. should be implemented in accordance with the provisions of the current national standards and industry standards.
5.4.3 Urban surveying and mapping should be implemented according to the requirements of technical design. When changes are required, they should be approved according to the original technical design approval procedures. After the project is completed, the results data should be sorted out according to the requirements of technical design and relevant standards, and the technical summary should be compiled, and the results should be archived and submitted as required.
5.4.4 Urban surveying and mapping should establish a confidentiality mechanism for results. The management of confidential surveying and mapping results should comply with the current national regulations. 5.4.5 Urban surveying and mapping should strictly implement relevant safety laws, regulations and standards, establish safety production mechanisms and emergency plans, and take effective safety protection measures.
6 Basic control measurement
6.1 General provisions
6.1.1 Urban basic control measurement includes the determination of urban plane coordinate system, the establishment of plane control network, the establishment of elevation control network and the refinement of quasi-geoid.
6.1.2 Fixed markers or signs should be buried at control network points, and their types and arrangements should be based on the principle of stability and suitability for permanent preservation. 6.1.3 The control network should be continuously maintained to maintain its currentness, accuracy, reliability and suitability. 6.2 Plane coordinate system
The urban plane coordinate system shall meet the requirement that the projection length deformation value within the urban area shall not be greater than 25mm/km. 6.2.2 When the requirements of 6.2.1 are met, the urban plane coordinate system shall adopt a 3° Gaussian projection plane rectangular coordinate system, and its reference ellipsoid shall use the 2000 National Geodetic Coordinate System reference ellipsoid, the central meridian shall use the national unified 3° central meridian, and the projection surface shall use the reference ellipsoid surface. 6.2.3 When the requirements of 6.2.2 are not met, the following plane coordinate systems may be used in sequence: a) A Gauss projection plane rectangular coordinate system with a customized central meridian is used. Its reference ellipsoid adopts the reference ellipsoid of the 2000 National Geodetic Coordinate System, the projection surface adopts the reference spherical surface, and the central meridian is customized at the city center; b) A national unified 3° zone Gauss projection plane rectangular coordinate system with an elevation compensation surface is used. Its central meridian is the same as the national unified 3° zone:
c) A Gauss projection plane rectangular coordinate system with a customized central meridian and an elevation compensation surface is used. Its central meridian is customized at the city center;
A customized central meridian city plane coordinate system with different elevation compensation surfaces is defined for different regions. d
6.3 Plane control network
The urban plane control network consists of a plane framework network, a basic network and a dense network: generally laid out step by step6.3.2
The plane framework network is the basic control framework for establishing and maintaining the urban plane control network. It is composed of satellite navigation and positioning base station network points that are evenly distributed within its service range and are jointly measured with national high-level geodetic control points. It is advisable to build 1~2 bedrock stations or deep buried soil stations. The main technical requirements of the plane framework network should comply with the provisions of Table 1. Main technical requirements for urban plane framework network
Average distance between points
Baseline between adjacent points
Mean error in horizontal component
Baseline between adjacent points
Mean error in vertical component
Relative accuracy of each control point
Not less than 1×10-?
The plane basic network is the basic plane control network of the city. It can be encrypted based on the plane framework network using the GNSS measurement method. 6.3.3
According to the scale of the city, the plane basic network can choose the second or third class network and its network points should be leveled. The main technical requirements of the plane basic network should meet the requirements of Table 2.
Average distance between points
Main technical requirements for urban plane basic network
Baseline between adjacent points
Mean error in horizontal component
Baseline between adjacent points
Mean error in vertical component
Relative accuracy of each control point
Not less than 1×10-*
Not less than 1×10
6.3.4 Plane densification network can be densified and expanded based on plane basic network by GNSS measurement or traverse measurement method. According to the scale of the city, plane densification network is divided into four levels, first level, second level or third level, which can be laid out step by step or across levels. Plane densification network points of each level should also be used as elevation control network points. Each network point should have line of sight with at least one adjacent network point. The main technical requirements of plane densification network should comply with the provisions of CJ/T8.
Elevation control network
The urban elevation control network consists of the elevation primary network and the densification network, which are generally laid out step by step. 6.4.1
6.4.2 The primary elevation network is the basic elevation control network of the city. The first, second or third leveling network can be selected according to the scale of the city. It is advisable to include the plane framework network points, basic network points and important elevation control points into the primary elevation network. 6.4.3 The elevation density network is composed of the fourth-level leveling network that forms a ring line or is attached to the high-level leveling points. The network point spacing is 1km~2km, and its point positions should be shared with the plane density network points. 6.4.4 The main technical requirements of each leveling network shall comply with the provisions of Table 3. Table 3 Main technical requirements of each leveling network
Calculated from the round-trip measurement discrepancy
Per kilometer accidental mean error
Calculated from the loop closure error
Per kilometer total mean error
5 Refinement of quasi-geoid
TTKAa-cJouaKAa
GB/T35637—2017
The quasi-geoid can be refined by GNSS measurement, leveling, combined with gravity measurement, topographic measurement results and gravity field model. The refined quasi-geoid can be used for height control measurement. 6.5.2 The resolution of the quasi-geoid should not be less than 2.5'×2.5, and the accuracy should not be less than 50mm. The elevation anomaly control points used in the refinement of the quasi-geoid should use the basic grid points of the urban plane, and their elevation accuracy should not be lower than the accuracy of the three leveling grid points.
Geographic Information Data Acquisition
7.1 General Provisions
Urban geographic information data includes digital line drawing, digital orthophoto, digital true orthophoto, digital elevation model, digital surface model, new image, point cloud, three-dimensional city model and thematic geographic information data. 7.1.2 Geographic information data can be produced and updated by conventional measurement, GNSS measurement, photogrammetry and remote sensing. When using aerial photography or satellite remote sensing images to produce geographic information data, the ground resolution of the original image data should not be lower than the ground resolution required by the result data. Geographic information data with smaller scale, lower resolution or fineness can be obtained by using geographic information data with larger scale, higher resolution or fineness through cartographic synthesis, reducing resolution or fineness, etc. 7.1.3 Geographic information data should be updated in a timely manner according to the social and economic development of the city and the changes in geographic information. 7.2
Digital line data
The basic scales of urban digital line data are 1:500, 1:1000, 1:2000, 1:5000 and 1:10000. Each city can choose an appropriate series of scales according to its city size and application needs. 7.2.2
The basic contour interval of digital line data shall be selected according to the terrain type (see Table 4) and shall not be greater than the provisions of Table 5. Table 4 Terrain classification
Terrain type
Hills
Mountains
Scale
1:1000
1:2000
1:5000
1:10:000
Classification principle
Most areas with a ground slope below 2°Most areas Areas with surface slope of 2~6°
Areas with most surface slope of 6~25
Areas with most surface slope of more than 25\Basic contour interval of digital line drawing data
Basic contour interval/m
Hills
Mountains
GB/T35637—2017
TTrKAa-cJouaKAa
The plane accuracy of digital line drawing data is measured by the mean error of the plane position of obvious ground object points relative to the adjacent control points and the mean error of the spacing between adjacent ground object points. Its value should meet the requirements of Table 6. For difficult areas such as forests and hidden areas, the value specified in Table 6 can be relaxed by 0.5 times. Table 6
Plane accuracy of digital line drawing data
Meanwhile, the plane position error of obvious ground object points
Scale
1:1000
1:2000
1+5000
1:10:000
Plain land, hilly land
Mountainous land, high mountainous land
The elevation accuracy of digital line drawing data shall meet the following requirements: a)
Adjacent ground object points The mean error of the spacing
plain land, hilly land
mountainous land, high mountainous land
urban built-up areas and flat areas with basic contour interval of 0.5m, the mean error of the elevation annotation points of the digital line data with a scale of 1:500, 1:1000.1:2000 relative to the adjacent control points should not be greater than 0.15m: the elevation accuracy of other areas is measured by the mean error of the elevation of the contour line interpolation points relative to the adjacent control points, and should comply with the provisions of Table 7. For difficult areas such as forests and hidden areas, the elevation accuracy of the contour interpolation points of digital line drawing data can be relaxed by 0.5 times according to the specified value in Table 7. Table 7
Terrain type
Hills
Mountains
Elevation error (in units of basic contour interval) ≤1/3
≤2/3
The collection content and density of digital line drawing data shall comply with the provisions of CJJ/T8. 7.2.5
7.2.6The feature classification and code of digital line drawing data shall comply with the provisions of GB/T13923. If necessary, the classification and code can be increased according to the given rules: the attribute items and geometric representation of the elements shall comply with the provisions of GB/T20258.1 and GB/T20258.2. 7.2.7 The graphic expression of digital line drawing data shall comply with the provisions of GB/T20257.1 and GB/T20257.2: New symbols may be added according to the rules given in the graphic when necessary.
7.2.8 Digital line drawing data may be organized according to feature types and geometric features such as points, lines, and surfaces, and may be stored and managed according to regions, map sheets, feature types, or geometric features. When printing or printing output, the map sheet shall be used as the unit, and the inner frame size of the map sheet shall be 0.4m×0.5m or 0.5m×0.5m.
Digital orthophoto and digital true orthophoto data 7.3.1
The scale of urban digital orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000, 1:10000: The scale of digital true orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000. Each city can choose an appropriate series of scales according to the city size and application requirements. The ground resolution of digital orthophoto and digital true orthophoto data should comply with the provisions of Table 8. 6000
Division principle
Areas with most ground slopes below 2°Areas with most ground slopes between 2 and 6°
Areas with most ground slopes between 6 and 25
Areas with most ground slopes above 25\Basic contour interval of digital line drawing data
Basic contour interval/m
Hills
Mountains
GB/T35637—2017
TTrKAa-cJouaKAa
The plane accuracy of digital line drawing data is measured by the mean error of the plane position of obvious ground object points relative to the adjacent control points and the mean error of the spacing between adjacent ground object points. Its value should comply with the provisions of Table 6. For difficult areas such as forests and hidden areas, the value specified in Table 6 can be relaxed by 0.5 times. Table 6www.bzxz.net
Plane accuracy of digital line drawing data
Meanwhile, the plane position error of obvious ground object points
Scale
1:1000
1:2000
1+5000
1:10:000
Plain land, hilly land
Mountainous land, high mountainous land
The elevation accuracy of digital line drawing data shall meet the following requirements: a)
Adjacent ground object points The mean error of the spacing
plain land, hilly land
mountainous land, high mountainous land
urban built-up areas and flat areas with basic contour interval of 0.5m, the mean error of the elevation annotation points of the digital line data with a scale of 1:500, 1:1000.1:2000 relative to the adjacent control points should not be greater than 0.15m: the elevation accuracy of other areas is measured by the mean error of the elevation of the contour line interpolation points relative to the adjacent control points, and should comply with the provisions of Table 7. For difficult areas such as forests and hidden areas, the elevation accuracy of the contour interpolation points of digital line drawing data can be relaxed by 0.5 times according to the specified value in Table 7. Table 7
Terrain category
Hills
Mountains
Elevation error (in units of basic contour interval) ≤1/3
≤2/3
The collection content and density of digital line drawing data shall comply with the provisions of CJJ/T8. 7.2.5
7.2.6The feature classification and code of digital line drawing data shall comply with the provisions of GB/T13923. If necessary, the classification and code can be increased according to the given rules: the attribute items and geometric representation of the elements shall comply with the provisions of GB/T20258.1 and GB/T20258.2. 7.2.7 The graphic expression of digital line drawing data shall comply with the provisions of GB/T20257.1 and GB/T20257.2: New symbols may be added according to the rules given in the graphic when necessary.
7.2.8 Digital line drawing data may be organized according to feature types and geometric features such as points, lines, and surfaces, and may be stored and managed according to regions, map sheets, feature types, or geometric features. When printing or printing output, the map sheet shall be used as the unit, and the inner frame size of the map sheet shall be 0.4m×0.5m or 0.5m×0.5m.
Digital orthophoto and digital true orthophoto data 7.3.1
The scale of urban digital orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000, 1:10000: The scale of digital true orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000. Each city can choose an appropriate series of scales according to the city size and application requirements. The ground resolution of digital orthophoto and digital true orthophoto data should comply with the provisions of Table 8. 6000
Division principle
Areas with most ground slopes below 2°Areas with most ground slopes between 2 and 6°
Areas with most ground slopes between 6 and 25
Areas with most ground slopes above 25\Basic contour interval of digital line drawing data
Basic contour interval/m
Hills
Mountains
GB/T35637—2017
TTrKAa-cJouaKAa
The plane accuracy of digital line drawing data is measured by the mean error of the plane position of obvious ground object points relative to the adjacent control points and the mean error of the spacing between adjacent ground object points. Its value should comply with the provisions of Table 6. For difficult areas such as forests and hidden areas, the value specified in Table 6 can be relaxed by 0.5 times. Table 6
Plane accuracy of digital line drawing data
Meanwhile, the plane position error of obvious ground object points
Scale
1:1000
1:2000
1+5000
1:10:000
Plain land, hilly land
Mountainous land, high mountainous land
The elevation accuracy of digital line drawing data shall meet the following requirements: a)
Adjacent ground object points The mean error of the spacing
plain land, hilly land
mountainous land, high mountainous land
urban built-up areas and flat areas with basic contour interval of 0.5m, the mean error of the elevation annotation points of the digital line data with a scale of 1:500, 1:1000.1:2000 relative to the adjacent control points should not be greater than 0.15m: the elevation accuracy of other areas is measured by the mean error of the elevation of the contour line interpolation points relative to the adjacent control points, and should comply with the provisions of Table 7. For difficult areas such as forests and hidden areas, the elevation accuracy of the contour interpolation points of digital line drawing data can be relaxed by 0.5 times according to the specified value in Table 7. Table 7
Terrain category
Hills
Mountains
Elevation error (in units of basic contour interval) ≤1/3
≤2/3
The collection content and density of digital line drawing data shall comply with the provisions of CJJ/T8. 7.2.5
7.2.6The feature classification and code of digital line drawing data shall comply with the provisions of GB/T13923. If necessary, the classification and code can be increased according to the given rules: the attribute items and geometric representation of the elements shall comply with the provisions of GB/T20258.1 and GB/T20258.2. 7.2.7 The graphic expression of digital line drawing data shall comply with the provisions of GB/T20257.1 and GB/T20257.2: New symbols may be added according to the rules given in the graphic when necessary.
7.2.8 Digital line drawing data may be organized according to feature types and geometric features such as points, lines, and surfaces, and may be stored and managed according to regions, map sheets, feature types, or geometric features. When printing or printing output, the map sheet shall be used as the unit, and the inner frame size of the map sheet shall be 0.4m×0.5m or 0.5m×0.5m.
Digital orthophoto and digital true orthophoto data 7.3.1
The scale of urban digital orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000, 1:10000: The scale of digital true orthophoto data should be 1:500, 1:1000, 1:2000, 1:5000. Each city can choose an appropriate series of scales according to the city size and application requirements. The ground resolution of digital orthophoto and digital true orthophoto data should comply with the provisions of Table 8. 6
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.