In my latest blog post I showed you an intensity plot and a movie of the large commercial ships sailing in and out of the Baltic Sea through Fehmarnbelt.
But when building a tunnel across Fehmarnbelt it is also important to have knowledge about the intensity of movements with smaller local ships, such as pleasure boats, local fishing ships and the like.
The safety of these ships is equally important. Persons in a pleasure boat are vulnerable in collisions with construction vessels or large commercial ships and therefore a pleasure boat crossing Fehmarnbelt will draw much attention from construction vessels and the large commercial ships. When we know the intensity and sailing
pattern of the smaller local ships, we can plan how to handle this issue and introduce the necessary risk reducing measures for all vessels in Fehmarnbelt.
How to get that information?
So, how do we get the information we need? Luckily a radar is there is installed at the top of a silo in Rødbyhavn (Rødby Habour), and by using those data we were able to get an overview of the smaller local ships.
First we had to seek out and remove all the tracks from the larger commercial ships (also seen in AIS data – a GPS based system for tracking of ships).
We did that by creating an algorithm to match the tracks in radar with the tracks seen in AIS. As you see in the picture, the problem with matching data from the two data sets was that they were registered at almost the same spot at almost the same time.
Well, we solved the problem and were able to remove the international commercial traffic from the radar data and were left with illustrations of movements from smaller local ships, such as pleasure boats, local fishing ships and the like.
As you can see, the local traffic with smaller ships has quite another pattern than the international commercial traffic that I showed in my last blog post, and a significant seasonal variation: on top you see around 400 tracks in January, on the buttom you see around 1800 tracks in July.
Right now we continue our work on preparing the tender document and technical support for the Environmental Impact Assessment (EIA) in Denmark and in Germany. This time though, I will follow up on the four main contracts of the Fehmarn belt tunnel project and elaborate on the competitive dialogue described in the prequalification documents.
The contracts are so-called ‘design and build contracts’ where the contractors design their own project, but within a given framework in the tender documents.
Building the coast-to-coast link is such a large-scale and complex project that Femern A/S has divided the civil works into four major construction contracts. Several large, international contracting companies are expected to join forces in consortia in order to handle the job.
- The first contract concerns dredging of the seabed and land reclamation. Here the contractor is to dredge a trench, approx. 18 km long, approx. 80m wide and approx. 12m deep, in the Fehmarnbelt, where the tunnel will be placed.
- The second contract concerns the construction of the northern section of the tunnel, i.e. on the Danish side. The contractor is to carry out half of the actual tunnel construction and consequently build half of the tunnel element at a construction facility in Rødbyhavn.
- The third contract concerns the construction of the southern section of the tunnel, i.e. the German side. The contract contains principally the same elements as the northern tunnel contract.
- Finally, the fourth contract concerns the construction of portal structures, ramps and associated land facilities. The contractor is to build the tunnel’s two portals as well as cut-and-cover tunnels on land in Germany and Denmark, respectively.
Femern A/S is tendering in accordance with the Competitive Dialogue Procedure due to the scale and complexity of the project. Several issues are identified as dialogue aspects:
- risk allocation
- work areas
- parallel works and interfaces
- labour related topics and technical topics.
The dialogue will take place as a series of meetings between the owner and each bidder with the purpose of finding creative solutions, eliminating uncertainties and improving the quality of bids with respect to dialogue aspects.
As the technical consultant to Femern A/S we expect to be greatly involved in the technical part of the dialogue, to comment and analyse various design solutions and assess their consequences.
After the dialogue phase, the contractors are to submit binding bids including specified prices. This is expected to take place in Autumn 2014. The prices from this bidding round will form the basis of the updated information on the project’s construction finances which will be submitted to the Danish Parliament in connection with drafting the Construction Act.
Contracts will not be entered into until approval has been obtained in both Denmark and Germany.
I apologise for the blog being a bit quiet for a long time. It has been a very busy period for us where we have worked on three parallel processes: Preparation of the tender document and technical support to the Environmental Impact Assessment (EIA) in Denmark and in Germany. Continue reading “Prequalification for the Fehmarnbelt tunnel is a milestone for the project”
This blog post will pick up the underwater construction process where the last blog post left off. In the previous blog I explained how the trench was dredged, the element immersed and afterwards joined with the previously installed element; The bulkheads between the elements being removed to complete the operation. Continue reading “The construction of the Fehmarn tunnel”
This post will describe how a tunnel, consisting of 79 standard elements and 10 special elements, will be immersed and assembled under water. Continue reading “How is the Fehmarn tunnel constructed underwater?”
Immersed tube tunnelling is an efficient engineering solution for the Fehmarnbelt Fixed Link. An immersed tunnel is an underwater tunnel composed of segments, constructed elsewhere and then floated to the tunnel alignment to be sunk into place and then linked together.
Continue reading “Immersed Tube Tunnel”
I apologize for the blog being a bit quiet during the last month, but things have been rather hectic as the project is entering a new phase.
The 1st of June Wim Janssen (project manager from TEC in Holland) retired and Klavs Munch Koefoed (Rambøll) replaced him. Continue reading “New Project Manager on the Fehmarn Project”
The overall risk objective of the Fehmarnbelt tunnel is that it must be at least as safe to drive through the tunnel as it is driving on a highway in an open countryside. The tunnel has therefore been designed and has been given the status of an ordinary highway. Continue reading “Safety in the Fehmarnbelt tunnel”
You might never have heard of it, but some people (very few – 1-3% of the population) suffer from “tunnel phobia”. Tunnel anxiety/”tunnel phobia” is a broad popular term for a feeling that varies from real phobia Continue reading “Tunnel anxiety”
The landscape around the Fehmarn belt fixed link will, together with the immersed tunnel portal, make changes to the local area. The final landscape has not been decided yet, but in the Conceptual Design Phase, the Ramboll-Arup-TEC JV, has made the following proposal in close cooperation with Schonherr A/S and DHI.
Continue reading “The new landscape on Lolland”