At the Gardiola landslide a topographic monitoring network has been installed on March 2004.

The topographic network consists of a robotic total station (LEICA TCA 2003 with ATR - Automatic Target Recognition), located on the opposite valley side, and associated to a radio modem that allows download of the data by remote connection in a station located at Pomeifrè (1.5 km northeast to the test site and equipped by a PSTN connection), twenty-three optical target, and three reference points outside the landslide, located on stable ground.

The topographic network recorded from March 2004 to April 2009, with a temporal sampling of an hour.

The monitoring network allowed several automatic displacement measurements of the prisms installed, using a robotic total station Leica TCA 2003. This high-performance instrument for the ground displacement surveying, allow to measure the angle (Hz and V) and distance measurement. Data collected by this total station permit to improve knowledge on surface ground deformation, and the geomorphological evolution of the landslide.

In particular, the TCA 2003 total station used is characterized by:

- Angle-measurement accuracy: Standard deviation (ISO 17123-2) of 0.5” (0.15 mgon);

- Distance measurement (IR): Standard deviation (ISO 17123-4) 1mm + 1 ppm; Range 2.500 m, under average atmospheric conditions, i.e. visibility 15 km.

- Automatic target recognition (ATR), under good atmospheric conditions: Accuracy at below 200 m of 1 mm; Accuracy at 500 m of 2 mm – 3 mm.

For more information:

http://www.leica-geosystems.com/downloads123/zz/tps/tps2000/brochures/tps2000_brochure_it.pdf