Project Overview
Barmouth Viaduct, a 150 year old Grade II listed structure bridge, required replacement of its steelwork spans.
The task was complex due to the historical significance of the bridge, the need for precision in maintaining the appearance of the original structure, and the logistical challenges of working on a site with limited access.
Our Approach
Carver embarked on the project with meticulous planning and innovative strategies. We first conducted a full trial assembly in our yard of all four spans using purpose-made and reusable temporary works stools.
This ensured the trial assembly was within tolerance to how it would sit in its final position on site. To maintain the look of the original bridge, we used fake studs during the fabrication process.
Critical assemblies, including VIPA, VOSSLEH, and GUARD RAIL, were installed on the deck. These were height critical as the rail track would be sitting on these. Additionally, we created a full-length bespoke handrail system down the bridge.
Execution and Installation
Following the trial assembly, the bridge was disassembled for painting and then transported to the site. The sides of the two main spans were then reassembled on site
The decks were taken under the bridge by barge and lifted into place. Concurrently, the old bridge was cut away and removed by barge. In preparation for the installation of the new spans, pier head structures and ‘H frame’ were installed for the spans to sit on in their final position. The span sides were then rolled towards the track, lifted onto a rail cart, and transported down the track. After the old bridge was cut away, the new bridge sides were jacked out into position and decks lifted into place.
The outcome
Our temporary works allowed for the Mabey crane to run along the top of the two spans. After the old bridge was cut away, the new bridge sides were jacked into position and decks lifted into place.
The project was successfully completed in December 2023, demonstrating Carver’s commitment to delivering high-quality fabrication for the rail industry. The replacement of the Barmouth Viaduct’s steelwork spans not only preserved the historical integrity of the structure but enhanced its safety and functionality for modern use.