This new build housing estate, located approximately 1.6km to the south east of Worcester town centre, was situated on the site of a former factory, with significant demolition and groundworks required to prepare the site for redevelopment.
Taylor Wimpey acquired the land to build the 257 new residential properties, with the existing site including a steep slope formed from historic cutting along the eastern side of old factory. Inspection of the slope indicated ground conditions comprising mudstones and siltstones overlain by weathered material, with a number of both historic and recent shallow slips on the upper sections of the slope. Ground stability analysis indicated further stabilisation was required, and RSK Geosciences were engaged to develop a remedial works design to ensure long term slope stability.
The solution was to regrade up to 1m of weathered material from the surface of the slope and install an array of R32 hollow bar soil nails, ranging from 2m to 8m length, along with a facing system comprising erosion matting and steel mesh. Drainage was also specified, with the combined approach ensuring that the slope would be stabilised and protected from future weathering.
CAN Geotechnical were contracted to undertake the work on site, using the good site access to undertake the regrade and soil nail installation using long reach excavators. The 640 soil nails were installed using an auger drilling system, selected for best performance in the ground conditions on this site, which was also utilised to drill the boreholes for inclined drains installed into the slope to help reduce water levels. Two drill teams were mobilised to ensure an efficient programme, minimising disruption to the wider site, and the works were completed on time and to budget.
Duration: 10 weeks
Client: Taylor Wimpey