GB22021-2008

Basic specifications for national geodesy

国家大地测量基本技术规定

GB 22021-2008 es una norma nacional china obligatoria vigente: Basic specifications for national geodesy. Sector: Maquinaria. Enfoque: Métodos de ensayo. Entrada en vigor: 1 dic 2008.

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Resumen de cumplimiento

Este resumen está disponible por ahora solo en inglés.

Alcance y aplicabilidad

This standard applies to all geodetic activities conducted within the territory and other maritime jurisdictions of the People's Republic of China. It covers the establishment and maintenance of geodetic control networks, height control networks, and gravity control networks, as well as the determination of the quasi-geoid. It is mandatory for all surveying and mapping entities operating in China. The standard is referenced in national mapping regulations and applies to both terrestrial and marine surveying projects.

Requisitos técnicos

The standard specifies the fundamental technical indicators for China's national geodetic systems. It mandates the use of the CGCS2000 (China Geodetic Coordinate System 2000) as the unified national geodetic coordinate system, though a transition period allows the use of older systems like Beijing 1954 and Xi'an 1980. The geodetic control network is divided into four classes, with the first-class network consisting of Continuously Operating Reference Stations (CORS) to maintain the dynamic geocentric coordinate system. For height datums, China utilizes the 1985 National Height Datum based on the Yellow Sea mean sea level. The height control network is established through leveling and is categorized into four classes, with specific precision requirements for each. Surveying instruments must be legally calibrated before use. The standard also defines the gravity benchmark based on the 2000 National Gravity Basic Network, categorized into basic, first-class, and second-class networks. Furthermore, it outlines the requirements for the quasi-geoid, divided into national, provincial, and city levels, with specific resolution and precision limits. The depth datum for coastal waters uses the theoretical lowest tide level, while inland waters use the design water level.

Métodos de ensayo

The standard outlines the use of satellite positioning technologies for the first-class geodetic control network to ensure high-precision 3D geocentric coordinates. Precise leveling methods are mandated for the height control networks to maintain the 1985 National Height Datum. For gravity measurements, the standard requires relative and absolute gravity measurements to establish the gravity control networks and refine the quasi-geoid. All measurement processes must adhere to national technical specifications.

Preguntas frecuentes

What is the official geodetic coordinate system in China under GB 22021-2008?

The official coordinate system is the CGCS2000 (China Geodetic Coordinate System 2000), which is a right-handed Earth-fixed rectangular coordinate system.

Is GB 22021-2008 a mandatory standard?

Yes, all technical content in this standard is mandatory for geodetic activities in China.

What are the height and gravity datums specified in the standard?

The standard specifies the 1985 National Height Datum (based on the Yellow Sea mean sea level) and the 2000 National Gravity Basic Network as the national gravity datum.

The summary above provides a high-level overview of GB 22021-2008. To ensure complete compliance for your surveying and mapping projects in the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 22021-2008 today to access all detailed parameters, tables, and testing procedures.

Indicaciones de aplicabilidad

Tipo: Básica
CCS: A76
ICS: 07.040
Organismo competente: Ministry of Natural Resources (Surveying, Mapping and Geography)
Comité técnico: National Technical Committee on Geographic Information of Standardization Administration of China