Excavation works began in 2017 for the construction of a thrust wall to Auger Bore, to allow for the diversion of a gas main on Highways England’s £1.5billion A14 Cambridge to Huntingdon Improvement Scheme. This project includes both road widening and construction of a new stretch of road to help relieve congestion between the Girton Interchange and Brampton Hut. The four-year project is due to be completed in 2020.
The excavation was a short distance from the existing A14, which remained open whilst work was carried out. The ground conditions in the area where stiff clay and therefore raised concerns of achieving a suitable toe length to allow for a propped cantilevered design. To overcome this issue MGF provided a full temporary works design for a slit trench installation method that would use a modest toe on the sheets along with multiple levels of frame.
Working closely with the main contractor (the A14 Integrated Delivery Team), subcontractor and installation team, the frames were then built at our depot in East Anglia which allowed us to give the customer a faster turnaround and consisted of two levels of 203UC Brace – a heavy duty hydraulic bracing system with a double acting hydraulic power pack, that was combined with 3m and 0.6m extensions to form the leg brace. FKD Trench Sheets where also provided along with MGF Laddersafe and MGF Davitsafe to allow safe access and egress of operatives into the excavation.
Additional support was given by one of our local MGF Technical Sales Representatives, Hannah Hamilton who presented an in- depth tool box talk to the installation team prior to the installation of kit and was on hand with support throughout.