Local measurement
In geodesy, local measurement is understood to be a local measurement for the integration of new boundary lines, structures and parts of buildings, traffic areas and other objects in existing plans or ground-related information systems .
This also includes the subsequent determination of the coordinates of individual switch-on and limit points , twin and fork points , tower bolts , etc. in the fixed point field . Work on a larger scale, on the other hand, is referred to as remeasurement or mains connection .
Methods
The measurement is usually carried out with the theodolite or tachymeter by determining polar points if the previously marketed polygon points are still visible. Otherwise, the instrument is connected to certain coordinated points (building corners, border points , etc.) through free stationing , whereby the local measurement is also immediately integrated into the system of the national coordinates . If there are only a few details to be measured, the arched section is sometimes used, and in the case of right-angled buildings or parallel lines, pure distance measurement is also used. The effort is too high for GPS measurements that are otherwise frequent .
Single points
In addition to the new measurement points that sometimes have to be switched on, there are a number of tasks in which only individual or very few points have to be measured - for example
- new light masts , satellite antennas, sewer shafts
- Level , gravimeter points etc.
- Land divisions in the cadastral survey
- Surveying pillars at tunnel portals
- Connection of a tower bolt to the bell tower or vice versa
- local reference points for archeology and other small-scale surveys.
The recording of slightly curved courses (e.g. roadsides, sidewalks ) is often carried out from a tangent or a similar straight line by measuring the height of the arrow (distance from the straight line) at regular intervals . This procedure is also used to stake out curves.
Literature and web links
- Franz Ackerl: Geodesy and Photogrammetry , Chapter 20. Verlag Georg Fromme, Vienna 1959
- Heribert Kahmen: Surveying , Volume 1. De Gruyter Berlin, New York 1988, ISBN 3-11-011759-2
- Volker Matthews: Surveying I , BGTeubner, Stuttgart 2003
- State of Hessen: Measurement of buildings and their components