UB 310/151 Auch (Horseshoe) Viaduct was built in August 1894 and is an early steel railway viaduct with 9 separate simply supported spans and is supported on mass concrete piers and abutments. The structure carries the single non-electrified track of the West Highland Line over a valley which contains the Allt Kinglass watercourse. The structure also has an inspection walkway between the bottom chords of the main girders, and the cross girders support a cantilevered cess walkway on both elevations of the structure.
The upgrading works included strengthening and painting of the main structure to provide a 25 year maintenance free design life and increasing the capacity of the structure, renewal of the existing deck, provision of new track, access systems and ballast retention.
The drainage culverts under the line were renewed and rebuilt which, given the recent weather, is an important investment to protect the integrity and resilience of this crucial lifeline rail link.
As part of this project MHB Consultants was commissioned by Story Contracting to carry out a range of design services including:
- Site inspections
- Structural assessments
- Design of condition led repairs and strengthening
- Design of re-decking works
- Temporary works designs
See the Jacobite steam train cross over the newly refurbished Auch Viaduct, video by Story Contracting.