250:). The span of the swing bridge was 44 metres, providing a clear opening of 19 metres for river vessels on each side of a steam-powered, rotating, central pier that housed a cabin structure to allow operation of the steam engine. The central pier of the rotating span was protected by a timber cutwater that projected 43 metres up and down river. When the swing bridge was opened for river traffic, the ends of the rotating span were supported by structures at each end of the cutwater. The deck of the bridge was at a level of 7 metres above high water level and was supported on piers, each consisting of two stone columns connected by ironwork at top and base. Several aerial and deck level photographs of the bridge that illustrate the layout of the structure are available from the
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August 1920, a German warship, surrendered at the end of the First World War, broke free from its moorings and crashed into the bridge. The damage was serious enough to close the bridge to rail traffic until March 1921. As a result of these incidents, three stone piers were replaced by cast iron ones and additional cross-bracing was added to all piers.
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The bridge was damaged by collisions on at least three occasions. In 1899, gales drove a sailing ship against one of the piers. In
October 1904, a schooner also collided with one of the piers as it passed through the swing span, displacing some girders. Rail traffic was suspended until June 1905. In
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and both opened on 1 October 1885. The rail line was double track except for the bridge crossing, which was single track. The swing bridge design was necessary to allow the passage of shipping up and downstream at a time when
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The bridge was designed by the consulting civil engineers, Crouch and Hogg, and built by contractors Watt and Wilson, both of
Glasgow. The bridge was designed as a 492 metre long (1,615
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Throughout its existence the bridge had carried passenger and freight traffic, but both gradually declined and in the 1960s, the passenger service was replaced by a four-wheeled
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431:"Alloa, Railway Station View of Park Royal Railbus (M 79971) on the Alloa to Larbert service; photographed on last day of operation (see also under Larbert Station)"
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obtained authority through an Act of
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18:Bridge in Throsk to Alloa, United Kingdom
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217:The new line was also connected to the
385:Paxton, Roland; Shipway, Jim (2007).
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527:1971 disestablishments in Scotland
401:"Alloa Railway Bridge - Galleries"
330:"Alloa, Forth Rail Bridge (80302)"
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522:1885 establishments in Scotland
368:"Alloa bridge (Throsk Viaduct)"
267:Decline, closure and demolition
507:Demolished bridges in Scotland
449:"100 Weeks of Scotland: Alloa"
238:Alloa Viaduct and Swing Bridge
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512:Railway bridges in Scotland
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170:swing bridge
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127:Swing bridge
85:Rail traffic
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405:Rmweb.co.uk
174:River Forth
172:across the
94:River Forth
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44:Coordinates
491:Categories
415:29 January
279:References
54:56°06′04″N
57:3°49′52″W
474:Railscot
224:Stirling
154:Location
479:25 July
341:24 July
335:Canmore
303:25 July
273:railbus
192:History
133:History
90:Crosses
82:Carries
299:. 1897
248:chains
178:Throsk
146:Closed
138:Opened
123:Design
104:Throsk
100:Locale
532:Alloa
212:Alloa
182:Alloa
108:Alloa
481:2020
417:2018
343:2020
305:2020
244:feet
202:The
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149:1968
141:1885
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
