Using its bespoke ‘cable crawler’ access gantry, Spencer Bridge Engineering installed a dehumidification system on the main cables of the Humber Bridge in Hull. The system injects dry air into the cables at multiple locations, helping to slow corrosion and extend the service life of the structure. Spencer Bridge Engineering were commissioned to undertake these works due to the success of our Forth Road Bridge and M48 Severn River Crossing projects.
A key part of the process is the subsequent sealing of the cables with a proprietary material to create an air-tight environment.
The project scope included the design and installation of Spencer Bridge Engineering’s bespoke cable crawler access gantry system to facilitate safe and efficient access throughout the works. The scheme also involved the installation of a dehumidification system, followed by testing and commissioning activities to ensure full operational performance.
Given the nature of the structure and access requirements, the works involved significant operations at height, requiring specialist access solutions and careful planning throughout delivery.
Spencer Bridge Engineering’s approach meant that only a single carriageway possession for the installation of its bespoke ‘cable crawler’ gantry was required. Once the gantry had been manoeuvred from the delivery vehicle to the landing trestles, the carriageway was able be re-opened with only a lane-one closure required.
The in-house development of the ‘cable crawler’ gantry for suspension bridge main cables did not only have significant positive contributions to project programme, quality and methodology, it also created opportunities to carry out other essential works without the requirement for carriageway possessions on heavily used and critical transport routes. Any other methodology would require full-time lane closures, carriageway possessions, multiple crane lifts and significant disruption to users.
