Jamestown Viaduct, UK: strengthening of an early steel viaduct Available to Purchase

Jamestown Viaduct is a six-span railway viaduct constructed between 1887 and 1890 in Scotland, UK. The four main spans are of early steel construction, supported by masonry piers and abutments. Each of the steel spans comprises two simply supported main truss girders with cross-girders supported on the top chords at truss nodes with rail bearers and steel deck plates supporting ballasted track. The structure is Grade B listed. Previous structural assessments had shown that the viaduct did not meet Network Rail's requirements in terms of live load-carrying capacity. A design competition was used by Network Rail and Mowlem (now part of Carillion plc) to choose an outline design for strengthening. This paper describes the unique solution proposed and developed by Corus to take advantage of an eight-day possession for maintenance work on the nearby Forth Bridge. The work involved removal of the track and construction of an in situ reinforced concrete slab at deck level designed to act compositely with the existing truss girder top chords and cross-girders.