Auch Viaduct: Restoring the Horseshoe, Glasgow

Overview

UB 310/151 Auch (Horseshoe) Viaduct is an early steel railway viaduct with 9 No. separate simply supported spans. Each span comprises 2 No. external main girders supporting 19 No. transverse cross-girders and a longitudinal timber deck. All girders are built-up riveted truss girders.

Cross bracing and plan bracing to the soffit of the main girders provide lateral restraint to the structure. The structure supports 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 structure carries the single non-electrified track of the West Highland Line over a valley which contains the Allt Kinglass watercourse and supported on mass concrete piers and abutments.

The works included strengthening and painting of the main structure to provide 25 year Maintenance free design life and increasing the capacity of the structure to the relevant RA (Route Availability) Rating. Renewal of the existing deck, provision of new track, access systems and ballast retention.

The core renewal works were undertaken over a 9 day disruptive blockade with the overall programme duration of 9 months.

The technical lecture will discuss the strategy behind the project development, the technical difficulties encountered through the design phase and the ultimate delivery of a complex renewals scheme in often inhospitable conditions. The collaborative approach shown by Network Rail, MHB, Story Contracting, supply chain partners and stakeholders allowed the safe and efficient delivery of this scheme.