When it was built nearly 60 years ago, the suspension bridge across the Firth of Forth – an estuary on the north-western outskirts of Edinburgh, capital of Scotland – was the longest of its kind anywhere in Europe. With a total length of 2.5 km and a clear height of 44 m above sea level, it remains an imposing structure to this day and one of the region’s most iconic architectural landmarks. When a 120 m long and 36 m wide section of the maintenance facilities underneath the bridge was due for refurbishment, the specialists at I-Scaff Access Solutions Ltd. opted for a solution using Layher Allround Scaffolding and the aluminium FlexBeam. Apart from requiring significantly less equipment, this also halved the assembly time compared to the scaffolding material used so far.
Ever since the eighties, a series of maintenance bridges totalling some 10 km in length has existed underneath the road deck, enabling easy and safer access to the bridge itself for ongoing maintenance and inspection activities. Another temporary access level now had to be created, so that these maintenance facilities could undergo their own programme of maintenance. Conventional tube and coupler scaffolding of the kind that is still commonplace in the UK was used for the first five phases due to it’s flexibility. However, we were able to convince the specialists at I-Scaff Access Solutions Ltd., the British firm responsible for installing it, of the Layher Allround System’s manifold benefits in combination with the aluminium FlexBeam for the sixth phase.
The solution has to work in practice
“After watching a very impressive presentation, we decided to switch to Layher material for the sixth project phase. We were promised more efficiency and safety upfront ... and I must say, our high expectations were significantly exceeded in every respect”, said Ross Brown, Managing Director of I-Scaff Access Solutions Ltd., who oversaw the project on behalf of Millar Callaghan Engineering Services Ltd., the main contractor. “Using the Layher FlexBeam and the Allround System brought clear advantages for us every step of the way in terms of safety, efficiency and convenience.”
The work platform made it a simple task to dismantle the bridge being maintained and refurbish it next to the bridge itself. The amply dimensioned Layher Scaffolding System includes 4.5 m intervals that were greatly appreciated by the contractor’s personnel handling parts up to 9 m long, because it meant they could carry out their work underneath the bridge without any major obstructions. The basic structure comprised of Layher Allround components was suspended from the bridge’s own steelwork with the aid of couplers, with the individual standards linked in groups of three using wedge-head couplers. Layher steel decking in different lengths was located on the aluminium FlexBeams connected to these standards to form a reliable and sturdy work platform. By using decking in different lengths, the scaffolding could be adapted very flexibly to the situation on site.
Digital planning streamlines processes
The project design was directly undertaken by Kenneth Redman, Technical Manager at the Layher depot in Livingston, Scotland, using Layher’s LayPLAN CAD planning software in 3D. “By using LayPLAN CAD, a detailed 3D design offering virtual walk-on access was available to the client in VR format before the assembly work began. This presentation was further persuasive evidence that suspending the work platform from the bridge’s own steelwork is extremely beneficial”, commented Sean Pike, Layher UK’s Managing Director. What’s more, the detailed design allows potential sticking points to be identified early on and suitable solutions found. Additional guardrail and edge protector elements were fitted where required for work safety reasons. Finally, safety netting was installed under the full working area to prevent dropped objects from falling into the waterway below.
Certainly fast and efficient
I-Scaff Access Solutions Ltd. has its offices a good half an hour’s drive north-east of the bridge. The scaffolding specialists were also given training there in the assembly of the aluminium FlexBeam in the run-up to the project, enabling the Layher solution to be used very efficiently and bringing all its benefits to life on the site. “In fact, our philosophy is quite simple”, Brown continued. “We try to offer our customers the best possible service and advice at all times. That’s how we got to know our partner at Layher UK. Our two firms are a perfect match.” The scaffolding professionals at I-Scaff and Layher have been working together successfully since six years. Ross Brown’s final verdict could hardly be more positive: “We were able to assemble up to 80 square metres per day on average as a result of the Layher system – at high security requirements on the site. On top of that, the smaller number of components meant we could construct a platform that enabled the contractor’s personnel to undertake their work far more easily and with fewer obstructions. Last but not least, transport and storage needs were also minimised. We were able to demonstrate the tangible benefits of the Layher material to our customer, Millar Callaghan Engineering Services Ltd., in this way with a concrete project. I’m confident that this was only the beginning of yet another success story here in the UK.”
