29 August 2008

All bridges great and ... well, not so great

Two very nice sources have just come out showcasing a range of often spectacular bridges, mostly great although one or two merely bizarre.

Deputy Dog has big images of "nine amazingly unique bridges you may not have seen". Some are amazing and very attractive: the delightful Henderson Waves bridge in Singapore, for example. Arrayed on the opposite side are the strangely totalitarian Octavio Frias de Oliveira Bridge and the Juscelino Kubitschek Bridge, both in Brazil, triumphs of muscular spectacle but certainly not of elegance.

Also just out is the brochure for the Footbridge 2008 Awards. This has photos of all the winners and runners-up, plus extensive write-ups giving more background detail. There are few if any duds in here, with the Simone de Beauvoir Footbridge, Svratka River Bridge and the Sackler Crossing amongst the best of those featured. These are generally more sober structures than showcased at Deputy Dog, but they don't suffer for that.

27 August 2008

Bridges news roundup

A few more links to relevant news that I don't really want to address in detail (more original content coming soon, I promise!):

Viaduct price soars - The competition-winning Te Wero bridge (pictured above) in New Zealand has increased in budget from NZ$35m to NZ$51m. Some people remain keen, others note there are cheaper alternatives. Plenty of details at Auckland's project website including copies of the winning and runner-up submissions.

What are bridges for these days?

Venice cancels opening ceremony for hated Calatrava Bridge

Steel delay latest setback for Trinity River Bridge - another Calatrava bridge with cost concerns (pictured above)

Wear bridge designer's gloomy verdict - public consultation on secret competition-winning bridge due to start in September

14 August 2008

Bridge assessment explained

(Click on the cartoon for a larger version)

11 August 2008

McDowell & Benedetti on t' Telly

Channel 4 has tonight screened an interesting documentary ("Kevin McCloud and the Big Town Plan") about the Castleford Footbridge designed by McDowell + Benedetti, Alan Baxter Associates and Tony Gee & Partners. It's not yet up on their catchup website, but should be there to watch online tomorrow.

The 130m long footbridge has been shortlisted for awards including the World Architectural Festival Award, and is certainly a very impressive structure, taking advantage of a very attractive location just downstream of a weir on the flood-prone River Aire.

Hosted by Kevin McCloud, the documentary followed the bridge's progress from an invitation-only competition five years ago to its eventual opening this year. McCloud sees himself as promoting excellence in design to Joe Public, particularly excellence in architectural design. Engineering is often left by the wayside - lead architect Renato Benedetti is portrayed pretty much as the sole designer (he's the only person on the programme to acknowledge there were others), but much of this is because he offers one of the few fixed points in the bridges development - the initial structural engineer Alan Baxter Associates gave way to Tony Gee & Partners once the scheme was let as a design and build contract, not that you'd know any of that from the show.

Competing designer Mark Whitby is described alternately as an engineer and as an architect, while engineers (in the form of Rowecord, the steel fabricator) are much praised as the "craftsmen" or makers, but only the architect is seen as a designer. This might well be the case in this project (you can't tell from the programme), but it's an unwelcome hang-over from McCloud's day job televising domestic building design, where the structural engineer is rarely as key a participant as for an unusual bridge design. For example, Benedetti discusses the way in which seating on the bridge is used to disguise shallow fin-back box girders. These protrude above the deck, neatly reducing its apparent depth, but were they the architect's idea or the engineer's?

There's plenty more amusement on hand: the final design as built looks very much like that of rejected competitor Whitby, and nothing like the floating bridge that won Benedetti the job. I nearly coughed up my drink when he first suggested to the community judges that he could provide a bridge for £130,000 (the final cost is variously reported as £3.2m on the show and £4.8m on the Channel 4 website - that's a reasonable £6,100 per square metre of deck if you go with the lower of the two figures). A floating bridge would have been ridiculous at a flood-prone site where river levels can rise by 3m and river-borne debris includes boats and cars; however it took at least £50k of money wasted on a hydraulic study and the raised eyes of a sighing chap from the Environment Agency before this daft idea was ditched. Of course, it was the bargain-basement floating bridge and Benedetti's charm that had won over the "community champions" in the first place, and the local enthusiasts weren't deterred in their support however much the design changed course.

Yet again (assuming the programme to be "true" and ignoring how much it may have been edited to exaggerate the drama) the design competition format showed itself to be in many ways inferior to traditional optioneering, feasibility study, proper surveys etc. Most of the problems that the documentary suggested arose as the design stumbled onwards (land purchase costs, vulnerability to flood-borne impact, flood inundation during construction) were predictable from the start. Having said that, there's no doubt that it's an excellent design which well deserves the attention. And the film-makers have done a great job both of illustrating the difficulties such a project can experience, and the valuable contribution that high-quality design can make to a community.

One of the programme's key questions was whether the money spent will achieve its aims of triggering regeneration of a very run-down town. Surely it's long past time this question was studied properly - what's the change in economic activity in towns that build landmark bridges versus those that don't, and is there any real evidence that the benefits outweigh the costs? I'm not suggesting that simple economics should decide whether it's worth improving our aesthetic environment (on the contrary), just that it's a question where a proper answer might prove enlightening.

Lot's more very useful information on the design can be found at the Dezeen blog.

07 August 2008

Do RIBA bridge competitions work?

There have been a few interesting reports recently on RIBA bridge competitions, whether their rules are fair, and whether the winning bridges are too expensive or never get built.

I thought it might be interesting to review some of their competitions and see whether taken as a whole, they can be seen as a successful path to bridge procurement or not. Their website only holds results from 2005 onwards, so I've limited myself to those - I'm ignoring earlier RIBA-run bridge competitions including the London Millennium Bridge and Butterfly Bridge in Bedford.

Where I can find the information, I've included some key facts, such as the number of entrants, and the cost of the bridge per square metre of deck (a non-iconic footbridge can be built for as little as £1,000 per square metre, and £4,000 - £6,000 should be sufficient for many landmark bridges).

River Wear Crossing

Invitation only, 35 expressions of interest reduced to 6 shortlisted entrants. Winner announced in September 2005 as Techniker with Spence Associates. Budget £43 million. As of today, the winning entry has never been publicly revealed. However, it appears that proposals to build a bridge are moving ahead, with attempts to secure government funding and the more recent announcement that government funding has been secured, albeit for a "bog-standard" bridge. Cost per square metre of deck would have been about £4,000 based on the original budget.

River Avon Footbridge

Invitation only, with 5 shortlisted entrants. Winner announced in January 2007 as Schlaich Bergermann with Ian Ritchie Architects. Budget £2 million. Cancelled in July 2008 when budget reached £3.3 million, having spent £312,000 to get to planning application stage. Cost per square metre of deck would have been about £17,500.

Leeds-Liverpool Canal Footbridge

Open competition, with 88 entrants. Winner announced in February 2007 as Eckersley O'Callaghan with Softroom. Budget £400k. By May 2008, the budget was then stated as £700k, but planning permission had been secured. An August 2008 start on site was forecast. Cost per square metre of deck is £7,000 (based on planning drawings available at http://www.sefton.gov.uk/Default.aspx?page=5297 - search for "Pennington Road").

New Islington Footbridge

Open competition, with 87 entrants. Winner announced in July 2007 as Michael Hadi Associates with Gollifer Langston. Again, I seem to recall an original budget of about £350k. I've been unable to find any evidence of progress since the winner was declared. Does anyone know otherwise?

Sheffield Parkway Footbridge

Open competition, with "over 100" entrants. Winner announced in January 2008 as Ramboll Whitbybird with Tim Norlund. Budget was quoted as £1.5m in the original brief, but has been stated as £2m elsewhere. For the span of 37m and width of 4m stated in the brief, the £1.5m budget gives a cost per square metre of deck of £10,100, but the proposed design looks to be longer than that, so the real figure is probably much lower! Again, I can find no evidence of further progress, but it's still early days for this one.

River Douglas Footbridge

Open competition with 110 entrants, reduced to shortlist of 7. Winner set to be announced later this year. Budget is stated as £2-3 million in the brief, for a bridge about 85m long and 4m wide. That's about £5,880 - £8,820 per square metre of deck.


So, for the last 4 years, we can report 2 competitions that ended by going nowhere (Wear, Avon); 1 that seems to be going well (Liverpool); and 3 where it's too early yet to say (New Islington, Sheffield, River Douglas). Considering the amount of money spent by various parties (particularly for the open competitions, where the combined cost to the economy of all the entrants' time could easily exceed £0.25m per competition), that might not seem to be very good value.

This isn't necessarily a poke at RIBA and their competition office. For the two obvious failures, the key themes seem to be a lack of proper funding, feasibility study, and commitment from the promoters. But any cost-benefit analysis of these competitions would show a considerable loss to the wider economy in wasted professional time, both by unsuccessful entrants, and at Stratford, by the successful ones. The need for proper preparation by a client before running such a competition seems very clear.

04 August 2008

Bridges exhibition in London

It opened last week and runs until 20th September: "Spans: Viaducts, bridges and walkways", an exhibition of new bridges, mostly in Britain. There will also be a series of early-morning talks by some of the designers of the bridges on display.

The exhibition's catalogue shows 18 bridges, mostly reasonably current although including London's Millennium Bridge as something of a golden oldie (described somewhat daftly in the catalogue as "London's only pedestrian bridge"). Only 8 of these have actually been completed, which is fairly representative of the often uncertain funding situation for new landmark bridges.

The majority of the bridges are what can only be described as iconic, and several are structurally perverse, flag-bearing representatives of post-modernist abstraction. PoMo has finally hit the bridge design world several decades after building design, and of course any such trend is inescapable. However, bridge design more than building engineering cannot avoid the expression of structural form, and when the structure is as contorted and unnecessary as in several examples here, you have to ask whether there is a better approach.

The worst offenders include the Eel Net Bridge (pictured), Liverpool's Paradise Street Footbridge, and Bristol's Mobius Bridge. These follow the "blobitecture" trend where advanced CAD geometry allows the invention, analysis and construction of increasingly abstract forms, none of them bearing any relation to optimum structural behaviour. These blob-bridges are the post-modern descendents of the thin-shell and membrane engineering of masters like Eladio Dieste, Eduardo Torroja and Jörg Schlaich, and to my taste at least, completely lack the awe-inspiring elegance and charm of their ancestors.

It looks unlikely that I'll be in London to see the exhibition before it closes, so if anyone attends, please feel free to report in the comments!

Bridges news roundup

A few links to news that are relevant to this blog but that I don't want to digest in great detail here:

Design for iconic cable-stayed bridge in Dubai completed
(pictured above)

Michel Virlogeux interviewed - "We are in a very controversial period ... You have structures that are coming from fantasy, imagination and those from an artistic concept. This is not the way I like. I like structures for which the architecture is completely guided by the structural forces and the Millau Viaduct is a good example of th1at."

Yemen proposes 12.8km suspension bridge over Red Sea

World's largest arch bridge planned in Dubai

03 August 2008

River Douglas Footbridge - shortlist announced

RIBA have announced the 7 shortlisted entrants to their River Douglas Footbridge competition:
  • Amin Taha Architects, London
  • Guy Nordenson & Associates, USA
  • JDA with Arup, London
  • Nick Hancock Design Studio, London
  • NPS North West Ltd, Cumbria
  • Ramboll Whitbybird with Priestman Goode, London
  • t-hoch-n Architektur, Austria

There were 110 entries in total, which I think may be a new record, excessive even by the crazy standards of other recent RIBA open design competitions. It would be interesting to tot up the total amount of professional time spent on these competitions (at, say, £2k per entrant, that's over £200,000 spent on this single competition already). It might be even more interesting to compare that against what actually gets built and consider the cost/benefit balance to the various parties involved. Certainly, the client gets by far the best deal - loads of ideas for minimal outlay, plus as much publicity as they can squeeze out of it.

There are no pictures of any of the designs yet; apparently there will be public consultation in September.

The only non-shortlisted contender I could find on the web so far is by Architects in Residence. Please post in the comments if you find any others!

[PS: I ought to declare an interest, as I contributed to one of the 103 entries not shortlisted ...]