Boreholes can be drilled to depths of up to 60m at a variety of diameters including 150mm, 200mm and 300mm. Larger size casings can be obtained when required. The boreholes are advanced using a cutting tool that is dropped down the hole to retrieve the soils. This is carried out whilst simultaneously installing the temporary casing into the borehole, which prevents any loose soils collapsing into the borehole.
As the borehole is advanced in-situ testing can be undertaken including Standard Penetration Testing (SPT), borehole vane testing & permeability testing.
Drillers take both disturbed and undisturbed samples from the borehole. Experienced geo-environmental engineers will log the disturbed samples while the undisturbed samples will be recovered for laboratory testing.
When completed, geotechnical monitoring equipment can be installed directly into the boreholes to allow ongoing measurements to be taken by dedicated technicians, this includes gas and groundwater monitoring.
Strata’s cable percussive drilling crews are directly employed and are NVQ qualified in land drilling and British Drilling Association (BDA) audited to ensure high standards in both safety and quality.
The crews are supported by our qualified geotechnical engineers who undertake supervisory and technical duties including borehole logging and sampling.
Strata Geotechnics can provide difficult access and ground protection solutions for our standard Cable Percussion rigs and offer our unique VETRAK Restricted Access CP Rig for restricted access sites.
In conjunction with our inhouse rotary drilling crews we can advance the boreholes into bedrock through the base of the cable percussion boreholes and recover rock core samples.