Surveying. Measurement of the dimensional relationships between points, lines and physical features on or near the earth’s surface. Surveying basically determines horizontal distances, elevation differences, directions and angles. These obtained fundamental data are applied later to calculate areas and volumes, and to establish locations with respect to some coordinate system.
Summary
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- 1 Uses
- 1 Measurements
- 2 Reference or control
- 3 Surveying and topography
- 2 Sources
Applications
Surveying has as typical uses: the location and measurement of property limits; the outline of the location of buildings, bridges, channels, roads, sewers and conductive pipes for its construction; location of satellite launch and tracking stations ; and obtaining topographic information for planimetry and cartography .
Measurements
Horizontal distances are often assumed to be parallel to a common plane. Each measurement has both length and direction. Longitude is expressed in feet or meters, while direction is expressed as the azimuth angle formed at the point of observation between the object and the reference meridian, which is the north-south direction. This can be the true meridian, a grid meridian, or some other assumed meridian. In the United States, it is a norm to express angles using the minute-second degree system.
Reference or control
Reference or control is a concept that is applied to the position of the lines as well as their directions. In its simplest form, position control is an identifiable or understood point of origin for survey lines. In most coordinate systems, the origin to the west and south of the area in which the survey will be carried out is usually located for convenience, so that all the coordinates are positive and are in the northeast quadrant. The vertical measure represents the third dimension in the position of an object. Such a dimension is expressed as the distance over some reference surface, usually the mean sea level, and is called a reference plane. The mean sea level is determined by averaging the high and low tides during a lunar month, but, for greater safety,
Surveying and topography
Surveying was formerly considered the branch of topography intended for the delimitation of surfaces, the measurement of areas and the rectification of limits. Currently the international scientific community recognizes that it is an autonomous discipline, with its own statute and specific language that studies territorial objects at all scales, focusing on the establishment of all kinds of limits. In this way it produces cartographic documents and virtual infrastructure to establish plans, charts and maps, publicizing the property or government limits. In order to fulfill its objective, surveying thrives on topography , geometry , engineering , trigonometry , mathematics ,physics , law , geomorphology , soil science , architecture , history , computing , remote sensing.
