2 research outputs found
Modellierung der FelssturzgefÀhrdung am Mittelrhein- und Moseltal
Das Mittelrhein- und das Moseltal sind in den letzten Jahren hÀufig von SteinschlÀgen
und FelsstĂŒrzen betroffen gewesen. Durch die geomorphologische Grundsituation sowie
die dichte Verkehrsinfrastruktur innerhalb der TĂ€ler kommt es in diesem Gebiet immer wieder
zu erheblichen SchadensfÀllen. Diese haben weitreichende wirtschaftliche und infrastrukturelle
Folgen, bei denen auch PersonenschĂ€den nicht auszuschlieĂen sind. Es besteht daher der
konkrete Bedarf einer vorsorgenden Gefahrenanalyse um weitere SchÀden nach Möglichkeit zu
verhindern und PrĂ€ventionsmaĂnahmen zu realisieren. Der hier vorgestellte Forschungsansatz
hat die Ausweisung unterschiedlicher Gefahrenzonen von SteinschlĂ€gen und FelsstĂŒrzen fĂŒr die
anliegende Infrastruktur innerhalb des Mittelrhein- sowie Moseltals zum Ziel. DafĂŒr wurden auf
Basis von hochauflösenden LiDAR-GelÀndemodellen in die FlÀche gerechnete Steinschlagsimulationen
mittels der Open Source Software SAGA GIS durchgefĂŒhrt. Es konnte gezeigt werden,
dass durch die prÀzise Ausweisung der Steinschlagquellgebiete mittels Surf-Slope-Index, sowie
von Daten zur Vegetation und Geologie konkrete Felssturzereignisse plausibel nachgestellt werden
können. Durch die Validierung mittels der Rutschungsdatenbanken von LGB und LBM sowie
zahlreichen Groundchecks im GelÀnde konnten die Modellierungsergebnisse bestÀtigt und weitere
Verbesserungen erzielt werden. Anhand der Verschneidung mit realen Infrastrukturdaten
wurden VulnerabilitĂ€tsberechnungen durchgefĂŒhrt, die eine GefĂ€hrdungsabschĂ€tzung konkreter
Streckenabschnitte der Verkehrsinfrastruktur ermöglicht. Diese decken sich mit den tatsÀchlich
stattgefundenen SchadensfĂ€llen und SicherungsmaĂnahmen und können entsprechend als
plausibel eingeschĂ€tzt und fĂŒr eine GefĂ€hrdungszonierung verwendet werden.Abstract: In recent years the Middle Rhine- and Moselle-valley has often been affected by rockfall-
events. Due to the high geogenic exposure as well as the dense traffic infrastructure in the
valleys, significant cases of damage with far-reaching economic and infrastructural consequences
occurred in this area. Therefore there is a specific need for a precautionary risk analysis in
order to prevent further damage and to implement preventive measures. The research approach
presented here aims to identify different danger zones for adjacent infrastructure in the valleys.
For this purpose, rockfall simulations were calculated using the open source software SAGA GIS
on the base of high-resolution LiDAR terrain models. It could be shown that concrete rockfall
events were plausibly simulated through the precise identification of the rockfall source areas
and further input data like vegetation and geology. Validation using the LGB and LBM landslide
databases as well as numerous ground checks allowed the modelling results to be plausible. By
intersecting with real infrastructure data, it was possible to carry out risk assessments of specific
sections of roads and railway lines. These coincide with the actual cases of damage and safety
measures and can therefore be assessed as plausible and used for hazard zoning.researc
Multi-Methodological Investigation of the Biersdorf Hillslope Debris Flow (Rheinland-Pfalz, Germany) Associated to the Torrential Rainfall Event of 14 July 2021
The investigation of mass movements is of major interest in mountain regions as these events represent a significant hazard for people and cause severe damage to crucial infrastructure. The torrential rainfall event that mainly occurred on the 14 July 2021 in western Central Europe not only led to severe flooding catastrophes (e.g., Meuse, Ahr and Erft rivers) but also triggered hundreds of mass movements in the low mountain range. Here, we investigate a hillslope debris flow that occurred in Biersdorf in the Eifel area (Rhenish Massif, Rheinland-Pfalz) using a comprehensive geomorphologicalâgeophysical approach in order to better understand the triggering mechanisms and process dynamics. We combined field studies by means of Electrical Resistivity Tomography (ERT), Direct Push Hydraulic Profiling (HPT) and sediment coring with UAV-generated photogrammetry, as well as debris flow runout modelling. Our results show that for the Biersdorf hillslope debris flow, the geomorphological and geotectonic position played a crucial role. The hillslope debris flow was triggered at a normal fault separating well-draining limestones of the Lower Muschelkalk, from dense weathered clay and sandstones of the Upper Buntsandstein. The combination of a large surface runoff and strong interflow at the sliding surface caused a transformation from an initial translational slide into the high-energy and widespread hillslope debris flow. We further created and validated a stand-alone model of the debris flow on a local scale achieving promising results. The model yields a 97% match to the observed runout area as well as to deposition spreads and heights. Thus, our study provides a pathway for analyzing hillslope debris flows triggered by torrential rainfall events in low mountain ranges. General knowledge on hillslope debris flows, risk assessment and hazard prevention were improved, and results can be transferred to other regions to improve risk assessment and hazard prevention