Naslov
Independent control of GPS networks above long tunnels by astronomically determined azimuths or bearing angles

Autori
Solarić, Nikola ; Veršić, Zoran ; Špoljarić, Dragan

Izvornik
Survey review (0039-6265) 38 (2005), 298; 308-316

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Independent control of GPS networks above long tunnels; astronomically determined azimuths; astronomically determined bearing angles

Sažetak
At the Faculty of Geodesy, University of Zagreb, the automatic astronomical method of determining the azimuth by observing stars and the Sun has been developed within the frame of the scientific work. The classical astronomical method of azimuth determination is rather uneconomical because of extensive field measurements and long-lasting processing. The automation of measuring procedures and processing has enabled the application of the astronomical method in everyday surveying practice, and also in determining the tunnel cut direction, in the independent control of microtrilateration and GPS networks above tunnels. The importance of such an independent control of geodetic networks above tunnels lies in the fact: 1. That we control the relative positional relationships of the points at the entrance, and the exit of a tunnel, respectively, 2. That we control whether the exact value the deflection of the vertical have been taken into account. Namely, the deflection of the vertical at the points for traverse orientation used for entering the tunnel can be remarkable which can largely influence the traversing orientation, especially if the orientation sighting lines are steep. Applying the astronomical determination of azimuth as an independent control of trilateration or GPS networks over long tunnels, the surveyors can expect with more confidence that the tunnel be cut without any problems.

Izvorni jezik
Engleski

Znanstvena područja
Geodezija

POVEZANOST RADA