Rollenbergtunnel
The tunnel rising from north-west to south-east passes through shell lime, Letten keuper before subsequently encountering gyspum keuper in the form of base gypsum layers, the "Bochinger Horizont" and dark-red marl. The shell lime comprises very hard limestone and dolomite. Letten keuper: grey-black hard clay stones with intrusions of thick-bedded dolomites and sandstones, fine laminar to thin-bedded silt clay stones with various degrees of weathering. Dark-red marl: thin to medium-bedded silt clay stones. Lot 1: cross-sectional size of the 3-track access section and passing through the subsurface with only 6 m overburden. Lot 2: Difficult rock mechanical and hydrogeological conditions, which required a pilot tunnel as well as a test drive in the crown of the subsequent tunnel. Execution: Excavation and supporting in accordance with the NATM divided up into crown, bench and base. Middle and eastern drives - excavation via tunnel excavator. Western drive - bore and blasting. Creation of the inner shell with watertight reinforced concrete. The western portal in the vicinity of the 3-track line has an inner shell thickness of 1.20 m. In the connected zone, where the line is reduced to the standard 2-track, the lining thickness progressively decreases until it reaches the standard inner shell thickness of 40 cm. The 2- track eastern portal has an inner shell thickness of 80 cm.
- Country: Germany
- Region: Baden-Württemberg
- Tunnel utilization: Traffic
- Type of utilization: Main-line rail
- Client: Deutsche Bahn AG
- Main construction method: Trenchless
- Type of excavation: Excavator/Drill-and-blast
- Lining: Shotcrete
- No. of tubes: 1
- Tunnel total length: 3303 m, pilot tunnel: 1575 m
- Cross-section: 114-260 m² / pilot tunnel: 12, 19, 250 m²
- Contract Volume: 90 mill. DM
- Construction start/end: 31 months
- Opening: pilot tunnel September 1984; main tunnel 1987