Editing Tay Bridge (section)

===Design details===
[[Image:Tay Rail Bridge and Signal Box Wormit 2.JPG|thumb|right|Tay Bridge and Signal Box Wormit]]
[[File:Crossing the Tay Rail Bridge (northwards looking east).webm|thumb|right|Video showing view from northbound passenger train crossing bridge towards Dundee. Camera pointing primarily eastwards. (Contains some flickering).]]
[[File:Train crossing Tay Bridge (June 2019).webm|thumb|right|Video showing train approaching the Dundee end of the bridge.]]

The second Tay Bridge is a straightforward pier-and-lattice girder bridge; aside from its considerable length, it lacks any distinguishing characteristics.<ref name = "fife pictor"/> It has an overall length of {{convert|10780|ft||abbr=}}, which is covered by a total of 85 spans. These spans are ordinary brick arches, backed by cement concrete and set on top of piers which are supported by pairs of columns.<ref name = "fife pictor"/> Wanting to avoid a repeat of the fate of the First Tay Bridge, a principal intention of the design is stability, followed in importance by measures to minimise the bridge's weight and the adoption of aesthetically pleasing shaping where possible without compromising on structural strength.<ref name = "fife pictor"/>

The piers, which are primarily built from brick and concrete, are enclosed by a [[wrought iron]] caisson up to the low-water mark, above which a brick exterior is used, which cannot be infiltrated by water.<ref name = "fife pictor"/> The submerged portions are cased with blue vitrified brick. Above the high-water mark, each pair of piers has a connecting masonry section, terminating at the superstructure's base.<ref name = "fife pictor"/> Due to the high proportion of masonry on the piers, they were extremely heavy, which meant that Messrs Barlow worked to minimise the structure's weight without the piers being weakened. As such, a graceful iron superstructure was adopted.<ref name = "fife pictor"/>

Above the brickwork, two firmly braced octagonal columns continued upwards to meet the inner members in the form of an arch.<ref name = "fife pictor"/> Other members were used to provide a bed for the girders to provide for substantial pier that took much of its weight away from the basal area. Since the Second Tay Bridge's completion, the lattice girder arrangement has become a commonplace feature, near-universally adopted for bridge construction.<ref name = "fife pictor"/> The configuration provides for a high levels of compression strain despite the girders being comparatively light. The decking is composed of steel and is surrounded both sides of the bridge by a closely knit latticework, which functions as a wind screen as well as somewhat protecting the workers.<ref name = "fife pictor"/>