A59 Kex Gill Landslip Ground Investigation

Details

Due to historic slope stability issues and a more recent slope failure along an area of hillside located adjacent to the A59 in North Yorkshire Concept Engineering Consultants were commissioned to complete a geotechnical ground investigation in order to assist with identification of slip planes and the prevailing ground conditions which would be used to design a permanent remedial solution.

The scope of work included:

• Completion of 12No. boreholes using rotary drilling methods to a maximum depth of 40.50m bgl.
• In-situ geotechnical testing
• Installation of groundwater monitoring wells
• Installation of inclinometers for ground movement monitoring
• Detailed rock core logging to identify slip planes, fractures and differentiate natural and drilling induced features
• Post site monitoring including remote monitoring of movement pegs, ground water and inclinometer monitoring.

Challenges 

The works were carried out as emergency works as a result of ground movement and slip. Concept had to react extremely quickly proposing preparatory measures for working in areas of active land slip as well as extremely soft ground, an area of SSSI with protected species and habitats, in an exposed and remote environment and during potentially severe and hazardous weather conditions.

Prior to commencing any works Concept had to prepare the slopes for access of our specialist drilling plant and equipment by constructing access routes and safe working areas.

The works were planned and managed at very short notice working closely with Capita, North Yorkshire County Council, NYCC’s approved TM providers as well as the local landowners and tenant farmers to develop and maintain a “Safe Zone” at the toe of the slope and active slip.

Outcome

The ground investigation phase of the site works were successfully completed on time and to budget and to the Clients’ and his representative’ satisfaction.

A suite of geotechnical testing on samples obtained from the fieldworks was completed within Concepts in house geotechnical laboratory. All the sample data, borehole data and testing schedules were managed and transferred digitally. All subsequent monitoring results, testing results and the factual report were delivered in digital format using AGS 4.