CAN was contracted to stabilise a newly cut face on the M20 Junction 10a scheme to create a new motorway junction to improve local transport links and support development of the local area. To accommodate one of the new junction slip roads excavation of an existing slope was required, with the exposed face steepened to 60 degrees to allowing room for the new carriageway. The resultant face required permanent stabilisation to be carried out as the excavation was undertaken.
The existing embankment was excavated in benches of 1.5m height, with soil nails and a sprayed concrete facing installed over the face exposed with each bench prior to excavating the one below. CAN installed a total of 370 soil nails and sprayed 350 tonnes of concrete over the whole face in total, working in sequence with the earthworks. The CAN drilling system was mounted on a 25T zero tailswing excavator, with the drilling rig removed and a remote-controlled shotcrete excavator attachment used to spray the concrete as required, allowing seamless spraying and drilling with the same machine and minimal delays.
Following installation of the soil nails and sprayed concrete, the slope was then faced with a bespoke gabion facing, designed and built by CAN, improving the aesthetics of the finished solution. This consisted of an additional layer of welded mesh reinforcement and drainage over the sprayed concrete face, before installation of a wire mesh gabion facing filled with local stone.
Duration: 20 weeks
Client: Taylor Woodrow VINCI JV
Location: Ashford, Kent