Up to four times a year, the geodesists and geologists measure vibrations, rockfalls and mudslides on the mountain, which are triggered by erosion, temperature fluctuations and heavy rainfall. Localised deformations are even recorded continuously. Due to climate change, rock from the main dolomite is decomposing faster and faster and rockfalls will occur more frequently in the future. The data should help to better understand trigger factors and rockfall processes in order to predict the imminent collapse of rock masses and issue warnings.
The researchers use laser scanners to record 3D geodata and high-resolution point clouds and derive surface models from them. Tachymeters analyse rock towers and use them to determine the fall speeds and inclination angles of potentially collapsing rocks. Global navigation systems, including GPS, identify the stable areas of the summit. Seismic measurements, such as geophones, record the vibrations on the mountain, and fissurometers measure cracks in the rock.
A web-based app for 3D visualisation includes a digital twin of the mountain, created by photogrammetric digitisation of aerial images. Hotspots, change analyses, real-time monitoring data and annual comparisons are available for the Hochvogel.
Prof. Christoph Holst and Lukas Raffl from the Chair of Engineering Geodesy at the Department of Aerospace and Geodesy of TUM School of Engineering and Design developed and published innovative methods for the early detection of changes in the Hochvogel. High-resolution photogrammetric surveys, paired with digital twins from laser scans and reference points permanently marked in the rock, make it possible to identify the smallest rocks and localise them over time.
The derived results, in collaboration with the Chair of Landslide Research, provide unique information on spatial and temporal patterns of rockfall based on interdisciplinary research. They are a first step towards a better understanding of the role of sediment input for the frequency, magnitude and persistence of sediment waves in alpine catchments.
‘Our scientific work on the Hochvogel provides ideal conditions for observations and predictions. Thanks to the multi-method approach, we can follow the natural process and develop ways to adapt to the changes. To do this, it is important to have a well-founded basis for decision-making, on the basis of which the safety of local residents and hikers can be guaranteed and, for example, paths can be closed,’ explains Prof. Christoph Holst, Chair of Engineering Geodesy.
Links:
Project AlpSenseRely in cooperation with:
Chair of Landslide Research (coordination)
Chair of Engineering Geodesy
Professorship of Photogrammetry and Remote Sensing
Publication 1: Photogrammetric rockfall monitoring in Alpine environments using M3C2 and tracked motion vector
Publication 2: Extending geodetic networks for geo-monitoring by supervised point cloud matching