I've been in Bristol and took the opportunity to attend this debate, held at the
Arnolfini as part of the Architecture Centre's
Bridge150 season, celebrating 150 years since the inauguration of Brunel's
Clifton Suspension Bridge.
The debate was set up as architects against engineers, but from the start you could tell there would be a happy ending and both parties would make the case for living happily together ever after.
On the side of the engineers were
Ian Firth, of Flint and Neill, and
Julia Elton, engineering historian and proprietor of Elton Engineering Books.
Firth has been responsible for a significant number of innovative and architecturally interesting bridges. He introduced most of the key points that would recur throughout the debate. He noted the different involvement of the professions in projects of different scale, with the architect's role diminishing in inverse proportion to the size of the bridge. He was clear that both architects and engineers can be responsible for bad bridges, and that this usually occurs where one party fails to properly challenge their co-designer (
River Wear and
Glasgowbridge were offered as two examples). He tagged badly run design competitions where the engineering was sidelined or the client badly advised.
Firth identified the cult of the celebrity as one recent phenomenon which worked against engineers receiving proper recognition. Architects tend to be better known, and better at presenting themselves, and therefore are sometimes the only designer credited for a structure, however significant the engineer's role may be.
I was most pleased when he noted that good engineers could design very good bridges without architects involved, citing the work of
Schlaich Bergermann und Partner in the present day, and
Robert Maillart in the past. However, I was left with the impression that engineers should better aspire to working in collaboration with good architects, and that this was where good design was more likely to arise. Firth noted that the engineering education did not produce design-led, creative types, and that architects could contribute a better-trained imagination.
Elton also focused on education, citing a series of innovative engineers in the past who were perfectly capable of designing excellent structures with only minimal architectural assistance. She decried the lack of awareness amongst engineers about their forebears, suggesting this was why modern-day engineers lacked the confidence and context in which to be creative in their own right.
Jean-Rodolphe Peronnet was offered as an example: few in the audience had heard of one of the greatest structural engineers of the 18th century. In contrast, architects understand their history very well, and see themselves as part of a tradition of productive, creative personalities.
I have a lot of sympathy for this point, seeing it in both colleagues and students. I see it as an issue of aspiration: designers need role models to learn from and to set scales of ambition. Many engineers simply fail to understand how great they could be, and along with an education which concentrates on analysis to the almost total exclusion of communication, presentation and creative design, this really does hold them back. I don't personally think we need to develop engineers who are good collaborators with architects - I think we need engineers who can be great designers in their own right, and they will then be successful both alone and in collaboration.
The architectural side of the debate was presented by
Jim Eyre, of Wilkinson Eyre, and critic
Hugh Pearman. Eyre addressed many of the same points, and presented a few quite ugly examples of what an engineer could produce alone, citing Maillart's
Zuoz Bridge as the start of an era of boring engineer-designed bridges. Eyre noted that an architect's training made them far more aware of issues of context, culture, the experiential rather than solely functional side of a bridge, and that engineering training produced people ill-suited to addressing these issues.
He highlighted a period post-Zuoz when the engineer became king, and poor quality visual design resulted: the age of the motorway expansion, where least-cost no longer meant least-material (i.e. elegant), but fastest-to-build, and dull identikit concrete structures resulted.
Eyre also highlighted the key role that the procurement process plays in determining the success of design. Projects are increasingly led from a commercial rather than design perspective, with the contribution that design can make devalued. The increase in contractor-led design, in particular, has led to a focus on value-engineering which often reduces cost while simultaneously diminishing genuine value.
These are fair complaints, but appeared to attack the symptoms rather than the cause. Why do clients not value design? I think that both fee-paying clients and end-users, the public, share a lack of understanding of quality, and hence of value. Put simply, they do not know what a good bridge is, particularly where "good" is defined by engineering attributes. This even extends to visual aspects, where a widespread lack of visual literacy leads to some really spectacularly ugly architect-led designs being lauded as if they were actually good. The internet is full of such designs, and design competitons attract them like super-magnets. Instead, clients and the public often fall back on more straightforward yardsticks such as least-cost, or false signifiers of value, such as celebrity (the "it's Zaha Hadid so it must be good" syndrome).
Pearman did draw attention to the role of the public, who would not normally care about who "owns" bridge design. Architects were simply better at articulating their vision, at explaining design, but even they remain for the most part un-named and unknown to the general public.
I think this issue of "credit" for design is, or should be, a red herring. It seems to exercise many engineers who feel their contribution is often ignored, and while this is true, I think back to the motorway era. Although Jim Eyre suggested this period was the nadir of low-visual-quality, engineer-led design, I think there were also some very creative engineers at work during this period, highly innovative, and visually aware. I've recently posted a series of examples from the Sheffield-to-Leeds and Leeds-to-Manchester motorways on this blog: remarkable, sometimes beautiful structures, where no architect was involved, and where the engineers were not seeking any special recognition, but content to serve the public with humility.
I think it's vital that we train better-rounded engineers, who aspire to emulate the great engineers of the past. It's vital that we train people who can explain and articulate their designs. We should aim to encourage great designers who can transcend their training, from whichever background they come. But the relative roles of different designers only serve as the means towards an end, which is producing great bridges. More effort is require to explain to clients and end-users what "great" actually is, and why it can mean structures without flash, bling or spectacle. Only then can the people who use and pay for our bridges be in a position to "own" bridge design, and allow the designers to slip happily back into the shadows.
The steel arch is 18m tall, and sits in between two single-lane carriageways. The tied arch is a fabricated steel box, which varies in cross-section from base to crown in an unusual manner. A weathering steel spine box girder sits below the deck and is suspended from the arch by cables. The deck is supported on either side of the spine girder with weathering steel cantilevers.
The strength of the bridge's design is in its simplicity, particularly the use of the single arch, which renders it an immediately legible landmark. The arch is nicely shaped in elevation, being wider at its base than at its crown, but its width is a little disconcerting - it is wider at the crown than at the base. From some angles this gives it a top-heavy appearance, and it doesn't seem to make structural sense to me, as resistance to lateral buckling of the arch is to a large extent determined by the transverse fixity at the ends.
The cantilevers supporting the deck from below are another detail which is not entirely happy. They make use of the full depth of the spine beam, meaning they are stronger and stiffer than the shallower cantilevers more normally seen. This allows large parts of their material to be cut away, but also has the effect of making these essentially secondary elements visually quite prominent.
Perhaps this doesn't matter, as the underside of the bridge cannot be seen from most public vantage points. Although my photos show a small road passing below, this is a private access road behind a secure fence. Perhaps future developments in the area may render this part of the bridge more visible.
The issue of perspective is significant. To photograph the underside of the bridge I had to walk down a dead-end road and peer through a security fence. To photograph the bridge in elevation, I had to peer over a bridge parapet which clearly was not meant as a vantage point - there was no footway in front of it!
Along with the other interesting bridges to emerge from the Olympic park, Bridge 20 can't disguise the essential issue with the whole area, which is that it is criss-crossed with waterways and railway lines, both of which render significant parcels of land unreachable. The bridges are essential to make connections across this landscape, but the focus on their external appearance belies the fact that they are principally viewed by the people actually crossing each bridge. With this in mind, both Bridge 20 and Bridge 14 present a somewhat sterile, industrial appearance to their users, almost brutalist in their treatment of the streetscape.
