Access to the expansion joints at the Forth Road Bridge was limited and this resulted in not only restricted inspections but also long and difficult maintenance operations. The tight locations which staff had to carry out their tasks were even more congested when scaffold was required. It was agreed that custom built access platforms were required on both sides of the north and also both sides of the south towers. These platforms would be accessed from eight new staircases from the existing cycle path down to the existing maintenance gantries. From there, access to all the new suspended maintenance platforms could be achieved by new stairs unique to each area.
A full survey was carried out taking into account the camber of the bridge in both north to south directions as well as the camber to shed surface water going east to west.
Only high grade material was acceptable on this contract. In many cases the material required further laboratory testing and certification before being acceptable to use on the contract.
A full assembly of each platform was carried out at our workshop to ensure there were no complications on site during the installation. After a full assembly and MPI & ultrasonic testing of all welds, the platforms and staircases were sent for shot-blasting and painting.
Due to the confined spaces in which the installation was required, all suspended sections needed to be of a suitable size and weight that they could be manually lifted into position without any mechanical assistance. Any holes drilled in the original structure to accept the new steelwork were given a five coat paint system to ensure we were not compromising the integrity of the paint system. On completion of the contract we presented the client with a quality package containing material certification, NDT & weld reports, paint records and data sheets.
This contract has since been nominated for the Saltire Award for engineering excellence.
