Thursday, 31 March 2016

Building Bridges - A Real Greek Dilemma

So here is the problem. We have a ferry service that is the only physical communication route linking the town of Rio on the Peloponnese peninsula to Antirrio on mainland Greece. Charilaos Trikoupis was a 19th century prime minister of Greece; he suggested the idea of building a bridge between Rio and Antirrio. Unfortunately there were many factors that prevented the construction of such a bridge, one of which was the overwhelming cost of such a construction, as Greece was trying to get a late start in the Industrial Revolution.

The cost was not the only problem. Although the Straights of The Gulf of Corinth that the bridge would have to span was only 3km wide, opposite sides are situated on two different tectonic plates, making earthquakes in this region a very likely deterrent to building a safe bridge. There were other minor problems too (I am understating of course). Firstly, the seabed beneath the Gulf of Corinth is sand with no rocky structure and one side of the straights is subject to liquefaction in the event of a seismic event. The likely occurrence of earthquake also means that the bridge must be able to withstand a tsunami. It also has to be constructed in very deep water. Add to this, the incredibly high winds that are a feature of this area, causing a suspension bridge of this length to swing and you have barely scratched the surface of the difficulties facing designers of such a mammoth engineering project.

So now fast forward to the 1990s. The bridge has to be built. It is essential to the future of the Greek economy that there is a better way to cross The Gulf of Corinth: the ferry service is incapable of handling the volume of traffic and the journey takes 45 minutes each way. In modern day Greece there is also another dilemma that must be factored in to the equation: the stanchions of the bridge must be strong enough to withstand impact from a 180,000 ton tanker sailing at 18 knots. Oh, and there is just one more thing: the South Rion coast drifts several millimetres away from the North Antirion coast every year.

Would you like the job?  Well somebody wanted to do this and to help them they used a technique derived from studying the roots of the traditional Indian incense plant. The foundations of the bridge are constructed on top of narrow vertical poles, driven deep into the sand and then topped with gravel. Specialist machines had to be designed and built to work at depths of 65m and the stanchions were built in dry docks and towed into the Gulf.




The Rion-Antirion Bridge in Greece, opened to traffic in August 2004 and was the product of a seven-year construction project from 1998 to 2004. It is the world's longest cable-stayed bridge,
with a suspended deck of 2,252m, with four pylons, (where there are usually two) and has a reference span of 560m. Currently 10,000 vehicles cross on a daily basis. The total cost  of the project was 630,000,000 Euros. Since its completion it has won many awards for civil engineering, innovative lighting, structure and the Outstanding Project Award 2007.

So there you go. The seed of an idea, over one hundred years ago was a cause for celebration at the opening ceremony of the 2004 Athens Olympics. The man who had the idea didn't see it completed but he believed that it could be done. Others believed it could be done. They built it.

We all have bridges to build, don't we. Surely we can use this analogy for being determined: for having the strength to believe in our own ability to succeed, despite the obstacles that life puts in our path. If you think there is a gaping gulf between you and your destination, shrink it down to manageable bite sized bits. In other words, as my wonderful Dad would often advise us, "Cross your bridges when you reach them and don't meet defeat halfway."

The poem this week is from Sophie Hannah.

On Westminster Bridge

I don't believe the building of a bridge
Should be an image that belongs to peace.
Raised eyebrow or the river's hardened ridge,
It wouldn't want hostilities to cease.
Aloof on tiptoes, it deserts each side
For the high ground and, though it has to touch
Land that real lives have made undignified,
I don't believe it likes that very much.
It knows that every time we try to cross
To a new place, old grudges bind our feet.
It holds out little hope and feels no loss,
Indifferent more then neutral, when we meet
Halfway to transfer ownership of blame,
Then both of us go back the way we came.

Thanks for reading.  Adele
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