Following the instability of several areas of chalk cliff face adjacent to London Road, RSK was appointed as a designer to assess the slope instability and form a remediation strategy for the area. Risk areas were the footpath running along the base of the site as well as London Road atop the cliff with undermining of the road a possibility if protective measures were not put in place.
Lewes Nodular Chalk Formation
The site was divided up into three sections, the first was a smaller mound of limestone approximately 8 metres in height, 15 metres wide and made up of three visible sides, rock bolted and meshed using TECCO G65/3 and TECCO GREEN.
The main section of works comprised the cliff directly below London Road, the chalk in this area was around 20 metres in height, with the section running almost 100 metres. Drilling conditions on site were generally good with no flint bands present in the limestone, and a combination of grout and air flush was used. In total 630 holes were drilled across the site.
CAN Ltd was appointed as the contractor responsible for installation of the protective measures