Engineering magic (Still fitting the ar(T)chitecture category very well!): The Gotthard Base Tunnel
It’s been a while since I last got myself to publish on this blog and I’m happy to be back, funnily enough I’m back in London and that’s where this blog started.. so maybe it’s something about London and blog writing which influences me haha! But since we need to be realistic, I’m setting myself the goal of posting at least once a week (come on, is better than none!), so you should be able to read something interesting at least once a week – topic and day is at random! Oh the suspense haha! Then maybe, I can get back into the blogging flow and write more and more.. you know what it is..? It’s the Spring air! It’s finally Spring, the sky is blue, the birds are singing and the grass is green.. everything is different with this kind of air!
Yesterday I was on quite a long tube ride and since we are not lucky (or maybe we are lucky) to have the 3G network down there, I was “forced” to read. I had in my bag the latest issue of Time magazine and was reading about the Gotthard Base Tunnel. I heard about it, but never researched in-depth about it. It is, to say the least, astonishing!
But before we go ahead and check out why this tunnel is so astonishing, let me give a warning. IF you are fainthearted OR you vote for Green Parties, please LOOK AWAY NOW as this post is not for you – here I’ll be just talking from an engineering wonder point of view. Politics for another day.
The Gotthard Base Tunnel – A man-made world wonder!
Expected to open in June 2016, with more than 2,600 people working on it and at a cost of more than $10 billion, after 23 years of exhausting work, “the result is spectacular”, says Vivienne Walt from Time.
Through this tunnel, you will be able to fast forward from the Italian city of Milan to Zürich in less than three hours and further north into Germany, cutting the journey time by an hour.
The Gotthard Base Tunnel consists of two 57-kilometres-long single-track tubes, connected together every 325 metres by cross passages. Including all cross-passages, access tunnels and shafts, the total length of the tunnel system is over 152 km.
With a rock overburden of up to 2300 metres, the Gotthard Base Tunnel is also the world’s deepest railway tunnel constructed to date and the longest in the world, longer than the Seikan Tunnel in northern Japan and the Channel Tunnel connecting England and France.
But is not only the length that makes the Gotthard Base Tunnel so astonishing. Unlike other tunnels that travel partly under water, to build the Gotthard meant drilling under tropical temperatures due to the high pressure and meant drilling through exceedingly hard granite and quartz part of the Gotthard massif in the Alps.
Due to the high-pressure and high-temperatures, as high as 45°C, the tunnel has what Renzo Simoni, a Swiss civil engineer and CEO of AlpTransit Gotthard AG, the company that is overseeing the project, calls “the world’s most powerful ventilation system”.
Peter Schuster, of the Ernst Basler+Partner engineering firm, explains that they had to build refrigerated areas and ventilation equipment for the workers and once the tunnel starts operating, the temperature will be able to be kept down using the cooler air carried into the tunnel by the trains passing through.
Another challenge was the presence of water in the rock. One of the trickiest sections was the notorious Piora syncline, an area rich in dolomite where geologists feared they might encounter an expanse of rock filled with water and under high pressure. Luigi Jorio, from swissinfo.ch explains that to make the tunnel completely watertight, the engineers decided on an “umbrella” approach. The vault of the tunnel was covered with a layer of concrete and a waterproof mantle, which allows the water to flow down inside the walls and be channeled out through pipes placed under the railway tracks.
Not to mention the emergency exits, just mentioning it makes me get a headache.. how do you just.. do them? Peter Schuster explains that they had to design doors that can be opened by a child and that at the same time will stop the spread of fire and smoke. They have to work even if there is no electricity, and stand up to the wave of pressure, equal to ten tons, caused by trains going by. Basically… magic 😀
The Gotthard Base Tunnel, started in 1996, will soon be opened and become the longest rail tunnel in the world. It is a stunning example of engineering mastery and a route to be tried, at least once in a lifetime.
According to planners, around 300 trains should be able to speed through the Gotthard Base Tunnel twin tubes every day, at up to 250 kilometers per hour (155 mph) for passenger trains.
Today, April 12 2015, is 417 days away from the grand opening and if you feel a bit nerdy, here you can check out live cams from the Tunnel, sit back and enjoy!