Germany – Works for complete or part construction and civil engineering work – Fels- und Hangsicherung in Mauel Strecke 2651, km 59,345 | Bauleistung KIB

Rock and slope stabilisation on the Mauel section, km 59.345 of line 2651

Deutsche Bahn plans to secure a rock and slope embankment at risk of rockfall along the DB line 2651 (Cologne-Deutz – Berzdorf) between rail km 59.344 and 59.387, south of the Mauel Tunnel. This is a single-track, electrified main line with passenger and freight traffic, running between Windeck-Nord and Windeck-Süd. Following special inspections after several rockfall incidents, it was found that the affected rock section, due to the weathering of the underlying sandstone and unfavourably oriented and partially widely open joint sets, shows a significant instability. These geological structures promote both sliding and toppling movements of individual rock bodies. Additionally, frost-thaw cycles and root pressure from vegetation act destabilising and promote the progressive disintegration of the rock. Fresh detachment marks and recent fall events have been documented at several locations, repeatedly impairing the operational safety of the line. Based on the geotechnical assessment and the stability analysis, it is recommended to secure the rock cut. Planned is the installation of a rockfall protection fence and two rockfall protection nets with a catch apron to permanently protect rail operations from rockfall hazards.