Torvean Bridge - Inverness
Cleveland Bridge solves complex fabrication and environmental challenges to install new swing bridge
- Year: 2021
- Location: Inverness, Scotland
- Client: RJ McLeod
Stage 2 of the Inverness West Link project required the construction of a swing bridge over the Caledonian Canal to the south of the existing Tomnahurich swing bridge. This tandem bridge arrangement allows traffic on the A82 to flow freely at all times, while boats pass through one or other of the open swing bridges. Highland Council awarded the contract to RJ McLeod (Contractors), who needed to appoint an experienced bridge builder to fabricate and install the new bridge.
Cleveland Bridge offered all the expertise needed, including experience of installing complex swing bridge structures, and was selected to construct the new bridge to the design created by Capita Real Estate and Infrastructure.
The 39m-long bridge was fabricated from 150 tonnes of steel, plus 90 tonnes of steel counterweights to balance the bridge as it pivots. The bridge features a central 7.3m-wide cambered carriageway flanked on either side by cantilevered footways, each 3m wide.
Cleveland Bridge was responsible for fabricating, painting, delivering and assembling the bridge. The company conducted a full trial assembly at its factory in Darlington to ensure all components were fabricated accurately. The structure was divided into six fully welded units, which were each delivered to site on a just-in-time basis, then craned onto temporary works using a 500-tonne mobile crane. The sections were then connected and welded together.
The steel counterweight blocks were installed at the tail of the bridge once most on-site welding had been completed. The space around these steel blocks was filled with concrete to achieve the required weight for bridge balancing. The bridge was assembled in its open position, before being de-jacked onto permanent works ready for commissioning.
The bridge design posed considerable fabrication challenges, which meant Cleveland Bridge had to work to extremely tight tolerances. The main carriageway deck required cross frames to be fitted accurately over a 4.8m cambered deck with eight longitudinal troughs. Cleveland Bridge ensured the trough profiles were formed to the correct detail, and positioned to a 1mm tolerance when fitted on the submerged arcwelding machine used for deck panel stiffening.
Completing a project of this complexity demanded close working relationships between all sub-contractors. Cleveland Bridge coordinated its work closely with the client’s mechanical and electrical contractors, and worked with the scaffolding providers to ensure the bridge encapsulation created the right environment for all finishing works.
Cleveland Bridge developed a positive relationship with main contractor RJ McLeod, providing regular updates and rearranging work schedules in response to issues as they arose, to ensure the project was completed on time.
We were impressed with Cleveland Bridge UK’s technical expertise and experience in fabricating bridges of this complexity. A collaborative working relationship was established at the outset with all parties which has been beneficial throughout the delivery of this project.Steve Scott RJ McLeod