Footbridge Awards 2011 - aesthetics up to 30m span

Excellent! Those spiffy bloggers at Frame and Form have provided some images of the structures shortlisted for these awards, kindly saving me the bother and making it easier for me to comment on some of the entrants. So far, they've posted pictures of the entries under the short span (below 30 metres) / aesthetics category - go to their post for the images, I won't repost them here.

Judged purely on aesthetics, I'd want the Castleford Footbridge to win. It's a beautifully well-judged structure, tip-toeing gracefully across the river like a slow-motion ballerina, artful and expressive without ever having to be inappropriately demonstrative. It doesn't exhibit the need to show off, but its sinuous layout, use of the main girders as benches, and extensive presence of timber, all offer a humanistic approach to bridge design that's entirely appropriate to its setting.

Lisbon's Glass Bridge is technically impressive but somehow a bit inert, too simply cylindrical. The Corporation Street Bridge in Manchester does it better, as did the Glazen Brug in Rotterdam.

The Bracklinn Falls Bridge, at Callander in Scotland is another structure which is undoubtedly interesting but not necessarily "beautiful". I plan to visit it at some point and cover it in more detail. The combination of huge, rustic tree trunks with more modern timber and steel elements is striking, as is the setting. However, the triangular elevation, while robustly pragmatic, has no finesse to it.

I find the Buitengragt Pedestrian Bridge, in Cape Town, South Africa, more disconcerting than attractive. The deck is supported by stays from an inverted steel pyramid. It gives an impression of instability, and its hard to see why a stayed bridge was justified for such a short span at all.

The Yale Hillhouse Pedestrian Bridges, in Connecticut, USA, are not my favourite bridges for overall appearance, but I hugely admire their ingenuity. I recall seeing these previously, and the perforated, corrugated steel webs remain a delight. The corrugations help to stiffen the upper member of the side trusses against buckling, as well as preventing buckling of the webs themselves, while allowing the web plate to be very thin. The perforations hark back to Ithiel Towne's 19th century lattice trusses, one of many old truss designs ripe for reinvention.

Together, these two features significantly reduce the weight of the girders (although clearly only at the expense of much increased fabrication costs). An article in the ASCE's Civil Engineering magazine explains more. It's a shame this design isn't in the "technical short span" category, it's a very impressive piece of structural engineering.

International Bridge Conference Awards 2011

Various 2011 award winners have been announced by the International Bridge Conference, which will be held in Pittsburgh, USA, from 5-8 June.

John A. Roebling Medal
Michael J. Abrahams, P.E., New York, NY, recognising an individual for lifetime achievement in bridge engineering

George S. Richardson Medal
Stonecutters Bridge, Hong Kong, for a single, recent outstanding achievement in bridge engineering

Gustav Lindenthal Medal
North Arm Fraser Crossing, British Columbia, Canada, for an outstanding structure that is also aesthetically and environmentally pleasing

Eugene C. Figg, Jr. Medal
Mike O'Callaghan-Pat Tillman Memorial (Hoover Dam By-Pass) Bridge, connecting Arizona and Nevada, for Signature Bridges, recognising a single recent outstanding achievement for bridge engineering, which is considered an icon to the community for which it is designed

Arthur C. Hayden Medal
Te Rewa Rewa Bridge in New Plymouth, New Zealand, recognising a single recent outstanding achievement in bridge engineering demonstrating vision and innovation in special use bridges

Engineering Excellence Award
FHWA Manual "Analysis and Design of Skewed and Curved Steel Bridges with LRFD Reference Manual", awarded to be special and beyond the traditional guidelines of the medal categories

James C. Cooper Student Award
Behrouz Ahafei , University of California at Irvine, for undergraduate and graduate students who demonstrate an interest and passion for bridge engineering

The IBC presents itself as "the" international bridge conference, but is generally dominated by North American attendance with a strong Asia-Pacific presence. It's nice to see the awards are more wide-ranging, although possibly still somewhat inward-looking - is an FHWA Manual really the most excellent example of bridge engineering worldwide in the last year?

I've covered the Te Rewa Rewa bridge here previously.

Bridges news roundup

'World's longest' composite bridge debuts in Madrid
44m long carbon-fibre reinforced plastic u-frame footbridge took 30 days to prepare and 2 hours for constructor Acciona to install.

Architectural secrets of Houston's newest landmark — the Rosemont Bridge, revealed
An interview with Julia Mandell of SWA Group regarding a new US$5m footbridge. The treatment of the balustrading wrapped around the trusses is nice, drawing on their experience from their previous footbridge near Houston's Hobby Center.

Dallas City Council approves cheaper alternative for McDermott Bridge over the Trinity River
It's hard to know where to start with this story. It was to be the second of three Santiago Calatrava-designed bridges in Dallas (the first is the US$93m Margaret Hunt Hill Bridge, spanning 365m, and due to be completed later this year). The Margaret McDermott Bridge was planned as a 610m long bridge with a 305m main span, with a road deck slung below a quartet of arches, the tallest of which would rise 76m. Cost estimates for this spectacular design varied between US$314m to US$500m, and despite securing some US$92m of external funding for the project, the state of Texas has found the bill to be simply too high.

Having ditched the Calatrava arches, they are reportedly going for a less extravagant US$220m project, which still seems grossly inflated for a bridge of this size. What's particularly striking, however, is the news that they want to retain Calatrava to design only the bicycle and pedestrian elements of the cut-price design, and will be paying him some US$10.7m to do so - US$2.1m left over from his incomplete arch bridge contract, US$3.5m of Dallas funds, and an amazing US$5m of donations from an anonymous philanthropist.

There is clearly an argument that it's worth paying over the odds for the prestige of a brand name designer, but with the iconic element of the bridge gone, it's hard to credit why anyone would pay so much money simply to design its footways.

Million pound bombshell could wreck Perth bridge plan
This project for a Sustrans-supported cycle bridge near Perth had already been struggling with land purchase issues, but having seemingly resolved those, it has now been hit by the design consultant's announcement that it may cost £1m more than expected - extra money that simply isn't in the budget. Indeed, it's not even that simple. An original estimate of £1.8m for construction costs was apparently based on a simple "per square metre" figure. However, according to the Perthshire Advertiser, an additional £755k for craneage costs was later added, with the capital cost rising first to £3.5m and then eventually to £5.25m.

The bridge design consists of three arch spans, 200m long in total, supporting a 3m wide deck. So, for the original £1.8m estimate, that works out at £3,000 per square metre, which is cheap for a landmark bridge, but certainly achievable for a footbridge with no unusual construction issues. The latest £5.25m estimate would work out at £8,750 per square metre, which is expensive for the relatively straightforward structural form, but not unreasonable given the difficult access for construction in a wide river.

What will happen next is unclear - I would guess the scheme will be dropped completely, although the simple exercise of inviting preliminary tenders or getting an ECI contractor on board might help increase cost certainty.

Renowned Architect Designs a New Pedestrian Bridge for Revere Beach
Rosales & Partners propose a cable-stayed footbridge which is simple and elegant.

Where to now? 10 years of 21st century bridge design

This could be an interesting talk, for anyone in the London area on 5th May.

The IABSE British Group's Annual Lecture is being presented by Keith Brownlie of Wilkinson Eyre, the venue is the Institution of Structural Engineers, near Victoria, with the lecture starting at 6pm. Full details are available online, including a flyer.

Brownlie has been prominently involved in many of Wilkinson Eyre's landmark bridge designs, including the Gateshead Millennium Bridge. The talk will address the influence of the Millennium structures on his design team's more recent projects, and "consider the bridge design market as it pulls clear of the influence of the Millennium".

I would expect it to be very interesting, as the turn of the Millennium and the flurry of design contests and investment in icons which followed was simultaneously a short-lived bubble and also a source of inspiration to bridge promoters everywhere. Was it a brief golden age, or a period which has permanently changed design aspirations, options for bridge procurement, and the way bridge design teams operate?

Shortlist announced for Footbridge Awards 2011

The shortlist has been announced for the 2011 Footbridge Awards. The winners will be announced at the Footbridge 2011 conference in Poland on 6th July.

I've included links below only if I've covered the bridge on this blog previously.

Aesthetics short

• Bracklinn Footbridge, Scotland
• Buitengragt Pedestrian Bridge, Cape Town, South Africa
• Castleford Footbridge, England
• Glass Bridge, Lisbon, Portugal
• Hillhouse Pedestrian Bridges, New Haven, CT, USA

Aesthetics medium

• Butarque Footbridge, Leganes, Spain
• Knokke Heist Footbridge, Belgium
• Lyon Confluence Footbridge, France
• Paloma Footbridge, Madrid, Spain
• Riverside Footbridge, Cambridge, UK
• Sant Fruitos Footbridge, Barcelona, Spain
• Te Rewa Rewa Bridge, New Plymouth, New Zealand

Aesthetics long

• Center Street Bridge, Des Moines, Iowa, USA
• College Bridge, Kortrijk, Belgium
• Esch-sur Alzette Footbridge, Luxembourg
• Footbridge la Defense, Paris, France
• Rhein-Herne Canal Footbridge, Gelsenkirchen, Germany

Technical short

• Buitengragt Pedestrian Bridge, Cape Town, South Africa
• Castleford Footbridge, England
• Glass Bridge, Lisbon, Portugal
• Marinic Bridge, Slovenia
• Stahlhillebrug, Belgium

Technical medium

• Bridge of Peace, Tblisi, Georgia
• Knokke Heist Footbridge, Belgium
• Paloma Footbridge, Madrid, Spain
• Riverside Footbridge, Cambridge, England
• Robert I Schroder Overcrossing, California, USA
• Tradeston Bridge, Glasgow, Scotland

Technical long

• College Bridge, Kortrijk, Belgium
• Center Street Bridge, Des Moines, Iowa, USA
• Footbridge la Defense, Paris, France
• Forthside Bridge, Stirling, Scotland
• Kurilpa Bridge, Brisbane, Australia
• Rhein-Herne Canal Footbridge, Gelsenkirchen, Germany

Last October, I put together my own list of bridges that I would have liked to see nominated for these awards. Particularly significant omissions from the shortlist are the Infinity Bridge and Ponte della Costituzione, although this may simply be because nobody bothered to nominate them.

I'll be attending the announcement of the winners, and will hopefully find time to cover them in more detail here when that happens. I haven't yet had a chance to look for details of the several shortlisted bridges which are unfamiliar to me, so I won't hazard any guesses as to which bridges will do well in the awards.

Calgary Peace Bridge in trouble again

I've reported extensively on the awkward progress of Santiago Calatrava's Peace Bridge in Calgary, with my last post in October noting the bridge was delayed until this January. Then, January came and went with no news, although it's now reported that several of the bridge welds have failed an independent inspection.

The scheme initially achieved bad publicity courtesy of the City of Calgary's decision to break its own procurement rules and award Calatrava the CAN$3m design contract without any competition. Unsurprisingly, tenders came in above budget, for a scheme which was already one of the most expensive footbridges ever conceived. The key steelwork fabrication sub-contract was awarded to a Spanish firm, with Canadian suppliers judged either too expensive or lacking the requisite expertise, prompting more grumbling from the locals.

It's therefore doubly embarrassing now that welds made in Spain have failed to pass muster once shipped to Canada and subjected to independent testing. It's not entirely clear what the welding flaws are, with the contractor saying:

"There are probably some deficiencies in the welding, but it could just be different testing results and specifications in Spain. Now we need to make sure there is conformity."

Elsewhere, Calgary's representative says:

"We're not seeing an even joint between joining the two plates of metal."

In some ways, it's astounding that the welds were not properly tested before the steelwork was shipped, but in the real world it is not unusual for something like this to go wrong, even on such a prestige project. Unless it turns out that it is all a matter of misinterpreting the standards for weld testing, then someone clearly needs a major slap on the wrist. As the welds are re-tested and debated, the date for completion of the bridge slips further back, such that now nobody is even confident to say it will be completed this year.

At least the client's costs should not overrun - the risk of errors in manufacture lies with the contractor under the D&B contract. That's on the assumption that the problem is not with the original client specification, of course.

Faced with questions on who is to blame, the Calgary Herald turns, with dizzying irrelevance, to "local architects", who say that the simple matter of getting welds right is unsurprisingly difficult on such complex work. And they should know, right?

Officials and politicians seem to be queueing up to make sure the blame is placed with the contractor rather than the designer, and I have some sympathy with this. However, I've seen the welds on a Calatrava bridge - enormous, chunky, beasts of metal deposition, all laboriously hand-welded because of the highly curved and geometrically complex joints required. While the contractor ought to know what they are taking on, it also must be recognised that the designer has a part to play in coming up with a structural form which is buildable safely, economically, and which makes high quality work straightforward rather than a headache. There is, ultimately, a price to be paid for the Peace Bridge's spectacularly daft helical geometry, and this is it.

While most commenters are sanguine about what has happened, I'd recommend the inimitable Rick Bell of the Calgary Sun for the contrarian view, that it's an almighty balls-up borne of the arrogance of politicians and experts.

While the Peace Bridge saga drags ever more slowly on, it's nice to see that Calgary's other landmark footbridge, the St Patrick's Island Bridge, designed by RFR, is making steady progress, having just received unanimous approval from a city committee. I hope Calgary's desire to make it out of bits of old oil pipeline doesn't lead to trouble down the line.

Meanwhile, in Dallas, another Calatrava design is bogged down by an unaffordable price tag and a lack of funding to match. At least the reported US$8m design fee appears safe.

And just to conclude, proposals to add a second deck to Calatrava's Sundial Bridge, in California, have hit a major hurdle as well, although in this case they've been blocked neither by cost nor cock-up, but simply by being exposed as an April Fool's Day story.

Open thread

A mixture of lack of time on my part, and a lack of interesting bridge news, means it is all quiet on the pontist front, and likely to remain so for a little while, what with workload and Easter holidays on the way. I have a few posts in gestation but they will take some time to get ready.

Rather than whistling aimlessly and drumming fingers impatiently on the (virtual) table, here's an open thread.

Is there some bridge-related news I've missed?

A topic you'd like me to cover in the future?

Something you meant to comment on previously but never got around to?

Here's your chance: just click the Comment link at the bottom of this post!