Project Description

Design optimization and 3D production model for the world’s longest immersed tunnel

The Fehmarnbelt tunnel will be an 18 km long immersed tunnel connecting Rødbyhavn on the Danish island of Lolland to the German island of Fehmarn. It will be the longest immersed tunnel in the world, consisting of a double-lane highway in both directions as well as two electrified rail tracks.

In the tender and dialogue phase, CN3 assisted the international contractor consortium, Femern Link Contractors (FLC), in the competition for three of the four general contracts. FLC is selected to build tunnels, portals and ramps.

CN3 was hired to fulfil the demanding BIM-requirements in the tender and dialogue phase. We contributed to the development of a complete BIM strategy for the project and assisted the design work through continuous verification of the consultant’s 2D design and development of detailed production models. CN3 modelled all permanent structures – incl. the immersed tunnel, portals and ramps, the connection between the immersed tunnel and the cut-and-cover and special elements – which resulted in a highly detailed production model, optimized both in relation to design and production. Furthermore, CN3 performed geometric verification of all concrete and alignments, as well as detailed reinforcement models, and earth models.

In addition to ensuring the efficient collaboration between all parties, the modelling work enabled the consortium to deliver a fully verified and constructible design, which can also be used as a complete and coordinated basis for production, operation and maintenance in the next phases of the project.

CLIENT: Femern
CONTRACTOR: Femern Link Contractors; VINCI Construction Grands Projects, Per Aarsleff, Wayss & Freytag Ingenieurbau, Max Bögl, CFE, Solétanche-Bachy International, BAM Infra, BAM International

LOD 400-500 production model
Design review and verification
Optimization for prefabrication
Digital production
Cut & bend schedules
Interface management
Integrated Project Delivery