BAM Nuttall, along with BAM Ritchies and their supply chain, installed more than 2,000 nails and bolts with steel mesh to stabilise the rock cutting at Bearsted during a nine-day closure of the railway.
The railway line was closed between Maidstone East-Ashford from Saturday 7th to Sunday 15th August 2021 and the work was completed as planned.
There have been numerous incidents in the 170-year-old cutting over the past 10 year, including four in 2020 – the most serious of which was when a train hit a boulder on the track.
More than 6,800 metres of soil nails were drilled into the slopes, with steel mesh installed to prevent any sliding rocks. Cabling will also be connected and tensioned to hold everything in place. According to main contractor BAM Nuttall, it was the most extensive earthwork stabilisation carried out using this method in the UK.
Site agent Adam Aspinall said: “The greatest challenge has been the logistical planning as we have had so much plant and equipment on track, and we have needed to work to incredibly short time frames and deadlines. Normally a blockade like this would take a couple of years to plan but we only had five months, so that gives an idea of the planning and organisation undertaken to make sure that these works were completed safely and on time.”
There were eight drilling rigs operating full time on the slope, seven of which were rail plant and one a long-reach rig, drilling from the top of the slope. Throughout the entire nine-day period there was 24/7 hour working operating in three shifts. In total this led to 20 hours of non-stop drilling every day, with 70 people working in each shift.
The blockade also provided the opportunity for engineers to work on power supply feeder cabling between Harrietsham and Charing and for other maintenance work such as track realignment, rail grinding and flood mitigation at other stations on the line.
Network Rail Kent and Sussex has posted this video report of the project, here.