11 May 2022

"An Encyclopaedia of World Bridges" by David McFetrich

This new book is the follow-up to the author's previous Encyclopaedia of British Bridges, which I reviewed in 2019 (and its predecessor, back in 2010).

It lists and briefly describes over 1200 bridges in over 170 different countries, and there truly is nothing else quite like it.

An Encyclopaedia of World Bridges (Pen and Sword Books, 352pp, 2022 - also available in ePub and Kindle format) starts with an introduction and useful glossary of terms, and finishes with 90 pages of Appendices (of which, more later). However the core of the book is an A-Z of bridges around the world: well-known, not-so-well-known, significant, and curious.

It's smaller in size, and shorter than its predecessor (British Bridges had 444 pages covering over 1600 bridges) but it's still a mammoth undertaking. I've pictured it as part of its family for scale.

The entry for each bridge has a paragraph giving key details, and every page in the main section is illustrated with colour photos, although less than half of the structures have an accompanying image. There is sufficient information in almost every case to answer key questions, and the internet will beckon if an entry particularly piques anyone's curiosity.

Nitpicking Pontists can go through the book looking for surprising omissions (and there are plenty - I will leave this as an exercise for readers to address through this blog's comments function, if they wish!) However, I found I discovered far more that was unknown to me than I felt was missing. There are bridges of every conceivable age, shape and size. The sheer variety gives the lie to the traditional idea that there are really only four types of bridge (beam, arch, suspension, and stayed), with plenty of bridges that defy these simple categorisations.

The Appendices include helpful indexes of bridges by country and according to key participants in construction, obstacle spanned etc. There is an excellent bibliography with over 325 entries (although sadly for true enthusiasts, the sources of information for each bridge are not linked to the bibiliography, as was the case in the British Bridges volume).

The most interesting Appendix offers no less than 76 lists of bridges by various categories, some obvious, some much less so. Here you will find lists of Inhabited Bridges, Highest Bridges, Monorail Bridges, Chain Suspension Bridges etc. But also the less obvious Copy Bridges, Bridges Stranded by Changes in the Course of Rivers, Natural Fibre Bridges, Pilgrim Routes over Bridges and many more. I found this a particularly intriguing section of the book, giving the reader a number of ways to engage with the topic other than simply flipping through from A to Z.

I can heartily recommend the book to anyone with an interest in the history or architecture of bridges. For the world tourist, it could easily have been titled 1001 Bridges to See Before You Die (and a few more), in the vein of the popular bucket-list books aimed at people who lack the time or opportunity to travel.

I must confess I have not actually read every page yet: but it will be sitting on my desk for the foreseeable future, a book to dip into repeatedly.

09 May 2022

Welsh Bridges: 23. Dernol Footbridge, River Wye

This was the third of three bridges that I tried to visit on the River Wye in Powys in August this year.

The first was barely a ghost, and the second a literal washout. Would it be third time lucky?

I parked up in a layby on the A470, north-east of the bridge, and followed a public right of way through the fields and downhill towards the site of the bridge.

A bridge! A palpable bridge!

Alan Crow's book Bridges on the River Wye indicates that a suspension footbridge was built here in 1975 by the Newbridge-on-Wye firm N.R. Hope. From the description, it is the same bridge that can be seen today, except that all or much of the fabric may have been renewed. Powys County Council tell me that the bridge was "refurbished" in 2018.

The bridge is of essentially the same design as the now-destroyed Cwmcoch footbridge, constructed by the same builder in 1967.

Timber towers sit on concrete footings, and support a steel tube or roller over which the main cables pass. Additional stay cables are attached to the rear face of the towers.

The main cables are anchored to steel cantilever beams at each end of the bridge. Three parapet wires on each side of the bridge are also tensioned against these cantilevers, and the tower stay cables are spliced into the lower of these parapet wires.

The bridge floor comprises three timber planks running longitudinally, sitting on transverse timber members. Every third cross-member also provides the support for braced parapet posts.

Below the bridge decking, six parallel wires run longitudinally, and these provide substantial support to the deck along most of its length, as there are no vertical hangers as you would expect on a conventional suspension bridge. The deck wires are anchored to steel cross-members attached to the main anchor stanchions.

The main suspension cables only directly support the middle part of the deck. The two cables pass below grooved longitudinal timber members on each edge of the bridge.

In the absence of the under-deck wires, this would be quite an unstable arrangement, as the central portion would "rock" longitudinally under load. The deck wires are therefore essential both to prevent that rocking, and to support the deck between the points where the main cables connect.

I've included a few more photographs to illustrate both the details and the setting of this attractive, economical bridge, and a video to show how much it moves under a single person load.

Further information:

08 May 2022

Welsh Bridges: 22. Cwmcoch Footbrige, River Wye

This is the next crossing of the River Wye upstream from  the Cwmbach Footbridge discussed in my previous post.

It was built in 1967 by N.R. Hope of Newbridge-on-Wye, a "swing" suspension bridge of total length around 53m. A wooden beam bridge had previously spanned the river here, before being destroyed in the 1960 floods.

If you were unaware that this bridge existed, you would never look for it. I parked in the entrance to a farm track (although I can't recommend this) on the A470, and walked downhill. There is also space to park on the minor road on the opposite side of the river.

And indeed ... there was no bridge to find. At least, not one that you can still cross.

Powys County Council have no record of the bridge, suggesting this may have been a private bridge as there is no recorded public right of way.

However, Alan Crow's book Bridges on the River Wye, indicates that the bridge was built by the council, after an application to the Ministry of Agriculture and Fisheries for a grant to build a vehicular bridge was rejected.

Considering that the remains of the bridge are still visible, attached to the western abutment, I guess that this bridge may have been destroyed in the floods of February 2020.

Peering closely at the debris of the bridge, it can be seen that there was a timber walkway, three planks wide, supported on timber cross-members. Below these are a set of six parallel wires, an arrangement similar to the Invermark Footbridge in Scotland. The remains of suspension towers and cables are also just about visible.

I have included a picture of this bridge from Crow's book, to show it as it once was.

Further information:

07 May 2022

Welsh Bridges: 21. Cwmbach Footbridge, River Wye

Back in August 2021 (yes, time has been moving slowly here at Pontist Towers), I had the chance to look for three interesting footbridges along the River Wye in Powys. I had discovered all three in Alan Crow's excellent 1995 book Bridges on the River Wye.

Unfortunately, my search was less successful than I had hoped!

To reach the first of these spans, I parked in a layby on the A470 (see Google Maps link below), then crossed the road and headed downhill towards the river. Slightly further south, a public right of way is marked on the OS map, but no bridge is shown.

Crow's book records that a "swing" bridge was built here in 1962, to replace a structure that had been destroyed by a flood in 1960. This is the term "swing" bridge in its colloquial sense, referring to a slightly unstable suspension bridge. It was demolished in 1991 on safety grounds, and a new bridge was installed in August 1994 by Tysons plc, of Liverpool.

This was the bridge I had come to see: an arched beam bridge constructed in laminated timber, described by Crow as "one of the most attractive small bridges on the River Wye".

Sadly, there was no bridge to be found. If you look very closely at my main photo, perhaps you can spot the abutments.

The concrete abutments are still there, as are the remnants of steel hinges attached to them. Originally, there was third hinge at the crown of the arch as well.

It's an attractive river setting, and it was disappointing there was no bridge.

Powys County Council have told me that the bridge was removed for safety reasons in 2013, "as it had reached the end of its working life". There are no plans to replace it. I imagine the public right of way saw very little use before anyway.

Since there was little else to see here, I have included an image from Alan Crow's book showing the previous bridges.

Further information:

27 July 2021

Email subscriptions update

Hello!

Yes, it's me.

This is a quick note aimed at the 314 readers who subscribe to get updates from the Happy Pontist via feedburner. That email subscription service is going to be switched off in August.

I am looking to transfer all email subscribers to the alternative platform follow.it instead. If you think you'd rather no longer receive emails from the Happy Pontist, that's fine, just click on any emails you get from follow.it to unsubscribe.

Obviously, blog posts are few and far between right now, but I'm not shutting the blog, so hopefully there will be more to come!

13 May 2021

Yorkshire Bridges: 33. Western Bank Bridge, Sheffield


Ah, it was good to get out and see an actual bridge again.

I'm not quite sure how I missed this beauty on my previous visits to Sheffield, but never mind.

It was built in 1969 to a design by Ove Arup and Partners and architect Yuzo Mikami. I say "it", but actually there are two bridges here, as shown in the cross-section below.


The bridges carry the steeply sloping A57 Western Bank highway above a pedestrian concourse area in the University of Sheffield campus. They are two-span structures, supported on single bearings below their tetrapodal centre pier, and a pair of bearings at each end.

The bridges were built in a period when the University campus was expanding, and the growth in road traffic had led to the highway being upgraded to a dual carriageway. Up to 10,000 pedestrians were reported to be crossing the road every day before the bridges were introduced.

The reinforced concrete slab decks vary in depth, being 1.2m deep over the central support and 0.84m at the abutments. It's a subtle feature that is not immediately obvious visually due to the large footway cantilevers on the edges of the deck.

Both decks are slightly curved in plan, but as can be seen in the photos, the main bridge deck slabs are straight, with the edge cantilevers varying in width to provide the curve.


From above, there is very little of interest to see. The interest is in the space created underneath the bridge. From below, this is a concrete roof held up on finger supports and providing some shelter from the weather. Glass blocks allow light through the central strip, and recently new lighting has been installed to make this a more attractive space at night.

It's a classic of modernist design, with some similarities to both Kingsgate Footbridge (1963) and Drochaid a' Chaolais Chumhaing (1984). The attraction is in its balance between the monolithic and the skeletal; it's clearly one "thing", like a sculpture, rather than one thing sitting upon another thing, like a conventional two-span road bridge.

The tetrapod supports have an interesting blend of straight and curved geometry: the outer edges form an inverted pyramid, while the inner surfaces of each arm are profiled with the curves of two intersecting hyperbolas. I'm not 100% convinced about the way the arms meet the deck slab and wonder whether a different detail would have been preferable e.g. having the arms project slightly from the side faces of the slab to give more of a "cradling" effect.

The sloping faces in front of the abutments were a conscious design choice, not so much to provide seating as to avoid the "tunnel" effect common to subways with vertical walls. The aim is to integrate the bridge with the adjacent landscaping. I guess the central tetrapods represent a similar visual impulse.

The block seating around the supports is not original. I wonder to what extent it was added to stop drunken students from bashing their heads into the angled support struts?

The concrete appears to have weathered well, and I'm left wondering why such a well-designed bridge isn't a little better known.


The article about the bridge in Arup Journal is well worth reading, including some excellent photographs, design drawings, explanations of the structural analysis, and an unexpected anecdote about students in mini-skirts.

The bridge was rewaterproofed, repaired and had new bearings installed in 2016.

Further information:

08 May 2021

"Link it! Masterpieces of Bridge Design" by Chris van Uffelen

There ought to be a name for this sort of coffee-table architecture book, churned out seemingly by the dozen every month, heavy on the photos, light on text, and filled with an uncritical gosh-gee-whizz approach to its subject. Publishers like Braun have a formula that works, whether the book is about bungalows, home conversions, factory design, corporate gardens, cinema architecture, bamboo architecture, apartment buildings, or, eventually bridges. And all those examples are just a small part of the output from one author, Chris van Uffelen.

Something similar can be found on architectural websites like Dezeen, Archboom, Architizer and Designboom: an ever-growing torrent of archi-gloss, much of it unedited from designer's self-promotional submissions. And make no mistake: it is responsible for a genuine and substantial dumbing down of how "design fans" perceive the built environment, such that even the worst examples of toxic architectural bloat are slurped down like nectar by an audience increasingly addicted to the hyperreal and incapable of rational analysis.

None of which is to say that I find nothing of value in "Link it! Masterpieces of Bridge Design" (Braun Publishing, 2014, 208pp).

This is essentially a sequel to van Uffelen's "Masterpieces: Bridge Architecture + Design" (2009), which I reviewed when it came out. I say "van Uffelen" as if he wrote these books, but they are actually put together by "Editorial Office van Uffelen", who provide publishers with the complete ready-made coffee-table service, even if much of that is simply emailing suitable architects and asking them to submit their marketing material. A disclaimer at the end of the book makes clear that if anything is incorrect, it's the fault of the design firms, not editors or publisher.

So: there's almost nothing in the book that you can't find freely on the internet, and essentially you're paying to fund the marketing efforts of the designers who participate in the publication. And yet ... there are plenty of structures and projects in this book that I was unaware of and intrigued to discover.

"Link It!" includes a smattering of generally remarkable bridges that should be well-known to dedicated pontists: Dublin's Samuel Beckett Bridge; the Millau Viaduct; the Hovenring; the Passerelle Simone-de-Beauvoir; Calgary's Peace Bridge; Jerusalem's Bridge of Strings; etc. I am sure these will be interesting and attractive examples of bridge design for the non-specialist (who are obviously the book's core audience).

Beyond that, there are bridges in China, Austria, Germany, Canada, the Netherlands, Belgium, Denmark, Indonesia which are interesting, in some cases attractive, and often have features that a designer could take inspiration from, or in others spot details to avoid. The quality of the designs is, inevitably, uneven, and each bridge has minimal explanation and certainly nothing in the way of criticism. There are, thankfully, only a handful of complete stinkers amongst those that have actually been built.

I mention that because the book also features a number of unbuilt bridges, generally with little or no detail on when they may be built, or whether they will happen at all. Some clearly won't, like the daft "Bouncing Bridge" proposed in Paris, the deliberately conceptual "Hydraspan" proposed for San Francisco, or the notorious Kazimierz Ludwinow Pedestrian Bridge, in Krakow, Poland.

There are a few designs which I would hope even the more cynical pontist would find appealing. Examples include the Wupperbrucke in Leverkusen, Germany; the timber truss Enniger Bridge in Switzerland; the Phyllis J. Tilley Memorial Footbridge in Texas; and the Green School Millennium Bridge, in Bali. Sadly, it's not hard to think of plenty of other fine bridges that didn't make the cut.

The photographs throughout the book are generally of an excellent quality that show off the subject matter to its best, although they are often the "day-before-opening" images beloved of the architectural press, showing the bridges pristine and generally unsullied even by people or traffic.

In summary, it's best to see this sort of book as a glossy brochure, assembled without any expert curation; but which can still provide some pleasant browsing if not taken too seriously.