After suspension bridges – what about Cable-Stayed bridges

Cable-stayed bridges seem to be taking over from suspension bridges so after discussing at Hungerford and Clifton, I thought I’d investigate this type. Although many have been built in the last 50 years or so, the design has been around for much longer. Some notable early bridges are either cable-stayed or a combination of suspension and cable-stayed:  the Victoria Bridge, Bath (1836) the Albert Bridge across the Thames (1872) and the Brooklyn Bridge in New York (1883)



Victoria Bridge and Albert Bridge

 The first modern cable-stayed bridge is usually quoted as the Strömsund Bridge in Sweden, built in 1955.

Strömsund Bridge

Since that date may have been built: the Queen Elizabeth II bridge which takes the M25 over the Thames and the Second Severn Crossing are two in the UK.

Second Severn Crossing

Probably the most famous is the Millau Bridge in France, designed by the French structural engineer Michel Virlogeux and British architect Norman Foster, it is the tallest bridge in the world. It also has the highest structure in France – one of the piers at 343M is taller than the Eiffel Tower (323M). The Millau has 7 piers and 8 spans. This, I believe, makes it the longest cable-stayed span in the world. Interestingly Wikipedia, in it’s list of longest cable-stayed bridges, doesn’t include the Millau because the others have longer approach bridges which are not cable-stayed.

Millau Bridge

The main difference between suspension and cable-stayed bridges is that in the latter, much of the weight of the bridge is taken by the cables to the anchorages which need to be substantial. In cable-stayed, the weight is taken to the piers. Also multiple-span suspension bridges are not possible.

Another recycled construction – Hungerford Bridge and the Clifton Suspension Bridge, Bristol

Another ‘green’ construction , but much older than the Olympic stadium is the Hnngerfrod Bridge across the Thames from Charing Cross to the South Bank near the Festival Hall. The original bridge was built by Isombard Kingdom Brunel in 1845. It was a suspension bridge linking the north bank of the Thames with the Hungerford Market – hence the name. 

When the railway company extended their track to the new Charing Cross station in 1859, they replaced the suspension bridge with a wrought iron gifder bridge designed by John Hawksmoor. At this stage, the suspension links were reused for the Clifton Suspension Bridge which still spans the Clifton Gorge in Bristol. 

We rather take for granted today engineering standards but in Brunel’s day, they didn’t have any standard components. Brunel had to calculate the size and strength of the links needed for his design. All the links were individually cast on site and tested to ensure they were strong enough to support the calculated weights. That they are still in use today supporting the Clifton bridge is a tribute to Brunel’s engineering skill.

The Olympics are nearly here – I’ve had a look at the stadium design

While the stadium doesn’t have the same iconic look as the Beijing “Bird’s Nest” stadium, it has a number of interesting features. One is that it is a very green building – I haven’t been able to find out how green, but one reference says “Most, if not all, of the structure was made with recycled materials like rejected plastic crates and excess concrete from other areas of the park”

The architect Peter Cook has also designed the stadium so that after the games the top sections can be removed, reducing the capacity from 80,000 to 25,000. The stadium has been shortlisted today for the Stirling Prize – the RIBA’s annual architecture prize. The full shortlist can be seen at http://ribastirlingprize.architecture.com/. The Guardian’s comments are at http://www.guardian.co.uk/artanddesign/2012/jul/22/riba-stirling-prize-shortlist-2012-revealed


More info about the stadium:


http://populous.com/project/london-2012/

http://www.artlog.com/2012/34-olympic-architecture-beijing-vs-london#.UAx1nGGe4oI

http://www.olympicgames2012london.org/londonolympicstadiumuniquedesign.html

http://www.designcruzer.com/london-olympics-stadium-olympics-games-2012/

A good day

A good day for two reasons. Firstly an important day for physics: CERN has confirmed with nearly 100% certainty that the Higgs Boson exists. I won’t try to explain - or understand it but it is a very significant confirmation of the explanation of matter. It’s existence was forecast in 1964: earlier models couldn’t explain mass (weight to us) until this particle was added to the models. The whole elementary particle and quantum mechanics world is fascinating but difficult to take in: electrons - whose existence is fundamental to our modern high-tech world - don’t exist as ‘things’ in the sense that we understand, rather they have a probability that places them over a range of locations with a most likely location. When in university, I played with tunnel diodes - devices that have negative electrical resistance which can be explained by this probability theory. Light normally behaves as waves but can also exhibit characteristics of particles - photons. Proving the existence of these elementary particles is a complex game: they only exist for fractions of a second and need complex mechanisms to detect their existence. 


The second ‘good day’ reason was a Young Enterprise event at the Cooper School, Bicester. Sell for Success is a day of business games to give students an intensive introduction to enterprise and business skills. Groups of year 11 (5th form in old currency) students have to design, market and finance a game console. We had five groups of about a dozen each today from a range of Oxford schools. I played the role of Supplier of the consoles - manufactured in India. Each company has to decide on the spec for the console, sort out financing (another adviser plays bank manager) and market the device once they’ve decided on all the options. They don’t make a real console, of course, but do make a mock-up and have to make a presentation to the judges and the rest of the students. 

It’s a high-pressure day, particularly as most of the groups come together for the first time so they have to build themselves into a team very rapidly before negotiating with bank manager and me. They all did exceptionally well, gelling as teams very rapidly and having great fun. I’m sure they have started to develop a range of skills that they will find very useful whatever career they chose. One of the teachers reported that several had said that based on their experience of the day, they want to take part in the YE Company Programme during the next academic year. This involves groups of students forming their own companies and developing and selling products or services: no business games, this is for real.


Apart from the fun of the day, all the students today were great. Youngsters get such a bad press these days but everyone I saw today was well behaved, courteous and mature. Not the image one sees in the press.


Altogether a great day!

I’m not sure what to call this – British science, engineering?

And now for something different: after the Lent poetry and the Jubilee, I’ve been looking for a theme. Richard Morrison in The Times yesterday has triggered something: his comment is headed “We do nostalgia well, but the future needs much more attention.”  Prompted by the nostalgia of the Thames Pageant, he argues that we need to make more of our design skills – “The curse of British Design over the past century has not been a lack of talent, but lack of the commercial nous to turn great drawing-board ideas into objects that will transform the lives of millions”


I half agree with this sentiment: we are not the best at turning our ideas into big commercial successes but we are also not good at owning up to what we are doing. So I’m going to try to find British scientific and engineering successes. I was hoping to quote more from Richard’s article but the Times website is misbehaving. (By the way, the web was invented by the British computer scientist Tim Berners-Lee.)


Let’s start with ARM microchips: did you know that most (90 to 95%) mobile phones are powered by chips designed and licensed by the Cambridge company ARM? They started life designing the BBC Micro (remember that?) and went on to design RISC (Reduced Instruction Set Computer) microchips. So the iPhone, the Samsung Galaxy (and, incidentally, the iPad) are powered by chips designed in the UK. If you really want to find out about RISC and ARM look them up on Wikipedia.

The Jubilee at Gt Missenden

First pictures at www.missendenchurch.org.uk/jubilee/

Trip to the Loire – Chateau de Brézé

We’re just back from a few days at Saumur on the Loire. One of the fascinating places we visited was the Chateau de Brézé: advertised as a chateau beneath a chateau, the comparatively modern building is built on a rock that has been lived in since the 11th century. Much of the Loire valley is tofu – a chalk-like rock. This has been dug out to provide building materials for hundreds of years, leaving vast underground caves. At Brézé, these man-made caves have been used for a range of activities: as living quarters originally, then stables and for defence. More recently, a wine press and a bakery have been excavated. The caves form excellent wine cellars, of course, a fact realised by the valley inhabitants some time ago.

The Chateau is surrounded by a moat which is 50 meters deep and it’s from this moat that the various caves are accessible.

The access to the Chateau is over a bridge that is quite scary...

... but the footbridge (no longer in use) is even more frightening

The chateau is surrounded by vines and we came away with a case of their Saumur Brut – made by the ‘traditional method’ (they are not allowed to call it the Champagne method any more – but it is the same.)

There is more information on the Chateau’s web site http://www.chateaudebreze.com/

Rainbow at Little Hampden – and Street Art

A wonderful rainbow at Little Hampden this evening. We all know the end of the rainbow is here!






Rather late, I’m afraid, here are pictures of the Street Art on the final day of Zone Plus:

More Zone Plus

Here are pictures of the Treasure Hunt - Thursday morning and Street Dance - Thursday aftrnoon:









Today we had Will Rosie from Graffiti Peace. Will ran a workshop for 26 youngsters all who went away with their own artwork. Here's an example, more pictures soon:

Another good day for Zone Plus

... actually two good days. Yesterday was in the Oldham Hall; Zone Fun in the morning and Cooking in the afternoon. Today we had the fantastic Treasure Hunt and Lydia Rose did a very professional job with the Street Dancing. Here are yesterday’s pictures, today’s to follow:

Zone Plus - day 1

Zone Plus started today. The morning session of African Drumming, led by Justine Hart of Hartbeats, went very well: 16 drummers including a few helpers. The Church was very noisy. Edna commented at some stage that it was good that nobody wanted a time for quiet prayer.

The Resound session in the afternoon was less well supported but was still thoroughly enjoyed by everyone.

Here are some pictures from the first day. Click on the pictures to see larger versions: 

Zone Plus starts tomorrow

Zone Plus starts tomorrow. The first day has African Drumming in the morning and the Resound children’s choir in the afternoon. I hope to post some pictures tomorrow.

The poetry in "The Heart's Time" continues through Easter week but I'm stopping now. We're meeting next Saturday for a bring-and-share evening to compare notes on our favourite poem.

Saturday 7th April

Another Denise Levertov: "Ikon: The Harrowing of Hell" Another poem that it's difficult to find any images for so I'm just reading it

Good Friday - 6th April

Today's poem is "Good Friday, 1613. Riding Westward" by John Donne. Brenda reads it. The version in the book has been spellchecked: there are several original versions on the web with words like 'Spheares' and 'forraigne'


Here's the first part from one version:



Let mans Soule be a Spheare, and then, in this,
The intelligence that moves, devotion is,
And as the other Spheares, by being growne
Subject to forraigne motion, lose their owne,
And being by others hurried every day,
Scarce in a yeare their naturall forme obey:
Pleasure or businesse, so, our Soules admit
For their first mover, and are whirld by it.

There's also a web site with Jeremy Northam reading the poem: click here