Talk:Wylam Railway Bridge

Dubious Age?

There is nothing dubious about saying that is one of the earliest examples in the world of a through-arch bridge when it is the oldest surviving example in the world and considering the history of its design, it is very likely the very first through-arch bridge of this design in the world. So to suggest that it is merely an early example is not dubious and requires no further discussion. Certainly the sign explaining the history of the bridge located on the Wylam side of the bridge claims it to be the very first example of this design in the world and I find no reason or evidence of an older bridge in existence to dispute this claim. Although I am unable to prove it, there is a good possibility that the design for the bridge was inspired by Stephenson's design of the High Level Bridge, which although built on pillars, demonstrates the ability for the possibility of a through arch bridge as the railway sits on top of the arches and the road sits between the arches... as the high level bridge predates the Wylam railway bridge and is not so far away, it strikes me as a distinct possibility - sadly we will never know.— Preceding unsigned comment added by 83.143.83.200 (talk) 21:18, 26 January 2017 (UTC)

It's some decades too late to be the oldest (not even first) through arch bridge (not even a tied arch bridge). Just look at Brunel's 1849 Windsor Railway Bridge for the most obvious precursor, which is both a through arch and a tied arch; and is still in mainline use. Andy Dingley (talk) 22:02, 26 January 2017 (UTC)

I have no idea whether or not this is one of the earliest examples of a through arch bridge, but it certainly appears to be a through arch bridge, whereas Windsor Railway Bridge is not. Arches of all forms exert outward forces. A through arch bridge is like a traditional arched bridge and transmits the horizontal forces onto massive abutments. Windsor is a a tied arch bridge (specifically a bowstring arch) which joins the two bottom ends of the arch with a tension member, in the case of Windsor and other bowstring arches this is the deck itself. Abutments as such aren't needed and the bridge supports only need to carry the weight of the bridge, which sits on top of them. There are two fairly easy and reliable ways of telling the two apart. If the bridge sits on top of its supports rather than between them then it has to be a tied arch. If it doesn't have diagonal bracing between the arch and the deck then it has to be a through arch. Zipperdeedoodah (talk) 21:22, 18 February 2017 (UTC)

I can make no sense of your last sentence.

A through arch bridge is defined by a load-carrying deck which passes beneath the crown of the arch, nothing more. It says nothing about how the forces are distributed within the arch or its abutments. Many arches are through, many are tied and many are simultaneously both. Windsor is both, Hagg Bank Bridge is a through arch but untied. Andy Dingley (talk) 02:53, 19 February 2017 (UTC)

We are using different definitions. Unfortunately I cannot find a definitive reference either way to say which of us is right. As I was taught, a through arch brige is distinct from a tied arch bridge and the two are mutually exclusive. A through arch bridge acts on its supports like a true arch, exerting outward as well as a downward forces. A tied arch bridge is essentially a beam, exerting only downward forces. In engineering terms the two are very different, however similar they may look. Zipperdeedoodah (talk) 21:02, 23 February 2017 (UTC)

Just found this out and thought it might be of interest: on reading WG Laws' article on his bridge in Proceedings of the Institution of Civil Engineers (https://www.icevirtuallibrary.com/doi/abs/10.1680/imotp.1879.22365) The final paragraph reads (for those who don't have access):

The Author makes no claim to originality of design, though only one example of this form of bridge has come under his notice, viz., a bridge for a carriage road, erected in 1833 by Mr. Leather, over the River Aire, at Leeds, the span being 140 feet or thereabouts. In that case the ribs were of cast iron, and not braced internally. It embodies, however, the principle of the arched rib and suspended roadway.

— WG Laws, RAILWAY BRIDGE OVER THE RIVER TYNE AT WYLAM, NORTHUMBERLAND

Clearly the Laws is aware of a similar design of bridge, i.e. the one at Leeds - South Accommodation Road Suspension Bridge (http://www.leodis.net/display.aspx?resourceIdentifier=2003919_21020144) but notes the differences in his design. I'm no expert but could this bridge be described as "through arch" as the traffic seems only to pass next to arches?

On a personal note, I was brought up in Wylam and was lead to believe that this was the first of it's type. rfwebster (talk) 02:45, 10 January 2018 (UTC)

Name of Bridge

This bridge is officially known as Hagg Bank Bridge. It is nearer to the hamlet of Hagg Bank than Wylam. I know of more people that call it Hagg Bank bridge than Points Bridge. Sco1996 | I will respond. 10:02, 5 October 2010 (UTC)

I added a redirect, so anyone entering Hagg Bank Bridge will arrive at this article. --DThomsen8 (talk) 00:34, 17 June 2012 (UTC)

The bridge was always referred to as the Points Bridge by the older inhabitants of Wylam... because the Points (where the north line and south line met) were located shortly after the bridge. Also Hagg Bank is part of Wylam Parish. — Preceding unsigned comment added by 82.221.104.11 (talk) 04:25, 3 December 2015 (UTC)

I am not sure of the "official" name of the bridge, but in it's listing it is called the | West Wylam Bridge though I've never heard any one refer to it as such nor have I heard of Bird Cage Bridge, or The Tin Bridge mentioned in the article, perhaps that's what people from Prudhoe call it?? For my own part I would refer to it as the points bridge or Hagg Bank bridge rfwebster (talk) 07:43, 13 January 2018 (UTC)

Requested move

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: No move. No clear justification nor consensus. Cúchullain ^t/c 17:51, 7 November 2012 (UTC)

---

---

Wylam Railway Bridge → Hagg Bank Bridge relisted --Mike Cline (talk) 12:52, 24 October 2012 (UTC) – Andy Dingley (talk) 16:56, 15 October 2012 (UTC)

• Relisting Comment: What is the rationale for this move? --Mike Cline (talk) 12:52, 24 October 2012 (UTC)

This is the common name for the bridge and is the most widely used. The name "Wylam Bridge" is only used outside the local area (it is indeed near to Wylam) as a constructed name based on the only local placename big enough to be printed on typical maps. It also ignores the fact there is more than one bridge at Wylam. Andy Dingley (talk) 16:53, 24 October 2012 (UTC)

• Oppose I considered a non-admin closure based on my finding that Wylam name is more common based on Google hits, but that felt too much like a supervote. As such, I'll just say I don't think we have sufficient evidence to justify this move. For better or worse, sometimes exonyms are the more common name. --BDD (talk) 16:48, 31 October 2012 (UTC)

The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.