The foundation of any economy is the trading of goods and services. Trade allows for specialization, which is largely why today's world is so prosperous.
While America has the state system, allowing trade freely between our fifty states, Europe has the European Union, a long-standing agreement based on ease of trade, immigration, and defense. Simply put, the easier goods and services can travel within the EU, the better off the EU is.
The EU has an incredible highway and railway system capable of shuffling anything between Italy and Finland and everywhere in between. But there's one missing piece…
This brings us to the Fehmarn Belt, the gap between northern Germany and southern Denmark. The cold waters of the Baltic Sea form a gap of roughly nineteen kilometers or twelve miles.
The gap forces all car, truck, and rail traffic one of two ways — either the long way through Denmark, adding hours and additional cost, or a ferry across the water, also expensive in time and money.
Denmark and Germany needed a solution, so engineers began exploring options across the water decades ago. Two traditional options were on the table—a huge bridge or a giant bored tunnel. But both had issues.
Engineers couldn’t pencil out the bridge with wind conditions, poor subsea soil, and cost. When they considered a bored tunnel, like the Channel Tunnel between England and France, cost also presented a challenge, as they’d need five individual tunnels to transport cars/trucks and rail across.
Fortunately, there was a third option: an immersed tube tunnel.
The concept is quite simple… Workers can build tunnel segments on land, block both ends, float each segment, and sink it. Connect the segments, and you have a tunnel. Easy.
But this method had only worked for tunnels up to six kilometers or four miles. How could they build one spanning over three times the distance?
Fehmarn Belt Contractors has been answering that question for over a decade, and construction officially kicked off in 2021.
A consortium of Dutch contractors, including Boskalis and Van Oord, called FBC was up first. They had to dredge a perfect channel across the seafloor for the tunnel segments to eventually rest within, which meant they brought in the big guns. A fleet of some of the world’s largest backhoe and suction dredges worked 24/7 to remove over fifteen million cubic meters (20M CY) of mud, sand, and rock.
They placed all material within deliberate placement areas, creating vast amounts of new land for construction and future recreation.
As they worked at sea, the second consortium, FLC, began work on the tunnel element factory, a vital aspect of the operation.
This is the bananas part…
Ready for some numbers?
Each element has five passageways—two for three lanes of traffic in both directions, two for rail traffic in both directions, and a service corridor.
A standard element weighs 73,500 tonnes and is 217 meters (712 feet long) long. To cross the channel, FLC must produce 89 elements in total.
The $1B factory they've built on the coastline features five lines, each capable of simultaneously producing elements. Each line is indoors to provide a consistent environment year-round for casting and curing.
As each element is ENORMOUS, they split them into nine segments, with one segment formed and poured at a time. As they finish one segment, they slide it out of the building, allowing room for the next.
After pouring all nine segments, the element is ready for final touches and bulkhead installation.
And before we get to the floating 73,500-tonne concrete blocks part of the story, the project will use fifty Eiffel Towers' worth of reinforcing steel!
Great, we have a finished element. Now, how do we get it to the bottom of the sea?
As I mentioned, each one is slid on rails out of the factory lines and into dry docks.
With an enormous gate, they can close the dry dock and flood it with seawater, floating the segment given the air trapped within it thanks to the bulkheads, or caps, at either end.
Tugs can then pull/push the floating element to the deep end, where they pump the added water out, leaving it floating at sea level.
After adding more weight to lower each element's buoyancy, tugs can tow each element out into the channel and, using special equipment for the project, lower each within the dredged trench.
The tolerance between each element? 10mm, or 0.4 inches. At the bottom of the ocean. I'm chuckling as I write this.
As they connect them, starting at either coastline, crews can remove the bulkheads and finish the tunnel as they place new elements. Eventually, the two sides will meet in the middle, forming a completed tunnel from one end to the other.
If you want to see INCREDIBLE videos and additional information on the project, check out the project's website, which is linked below. It's incredible how much they've invested in the animations and information to help inform the general public!
And stay tuned for YouTube videos explaining the project in greater detail later this year!
https://femern.com/the-construction/building-the-tunnel/
Dan Moon and Jenna Moon Co-Owners/Operators of Total Excavating talk about what it’s like to own a business while also running a household together. Dan has been on the jobsite most of his life (specifically for total excavation) and Jenna comes from a background in non-profit work, together they make quite the duo!
PALFINGER called and asked if I wanted to check out their latest and greatest service truck. They didn't have to twist my arm… This video features our visit with them in June. We spent the day with Thompson Tractor welder/fabricator Patrick, who, with the help of his wildly cool service truck, was adding height to a D8 coal blade. I've seen service trucks worldwide, and it's safe to say this Palfinger setup is among the nicest I know of. We had a lot of fun exploring the truck and getting in Patrick's way as he attempted to get real work done. Check out the link below to learn more about PALFINGER's service truck offerings!