The challenge
A very tight deadline from early design to installation within 3 weeks, which involved weekend working to ensure the forecourt ground was ready for tank delivery.
The other challenge was the mudstone ground conditions across a large excavation. We had to come up with a clear opening solution for the tank arrangements for the new forecourt.
Once access and ground conditions had been assessed, a full method statement, risk assessment and temporary works design was agreed between all parties.
Our solution
We supplied a modular groundworks solution that used our sheet piles supported by our Supershaft Plus clear span shoring frames, protected by our ladder access system.
The excavation was constructed to the 27m x 7m dimensions without the need for any internal bracing struts compromising the clear opening dimensions.
By using our sheet piles, the whole cofferdam was struck out in only 2 days. The sheet piles were specially selected to allow rapid installation and removal with minimum deflections and damage. The piling rig was able to handle the piles without the need for banksmen or piling operatives, which reduced the number of people involved and the removal of lifting chains was a key deciding factor in the improved safety plan for ISG.
The use of our modular Supershaft Plus frames allowed the minimum number of delivery lorries to and from site, giving further environmental benefits to the project. Each element of the frame could be simply installed using a traditional excavator, removing the need for crane and piling mat costs. The speed of assembly of the frame allowed excavation of the pit to begin immediately on completion.
To complete the excavation, we supplied the ladder access system on each end of the cofferdam, allowing landing stages with secure gate access systems to give the required 1.0m barrier protection for the pit.
The quick assembly was overseen by one of our engineers, which allowed the installation team and main contractor to address the installation programme from delivery to extraction and identify all the key safety features on site.
Another project delivered on time, another bespoke solution delivered. Customer delighted with the speed of delivery of the project and a solution that reduced the safety risks of having personnel in the excavation unnecessarily.
