WHAT IS WINDOWLESS SAMPLING?
Windowless Sampling is a specialist sampling technique that involves a narrow steel tube with a plastic liner, being driven into the ground in order to retrieve a sample.
Thanks to the plastic liner, the sample can be kept intact during the removals process, allowing for accurate results from the full depth of the samples.
During this sampling process, cylindrical steel tubes are drilled into the ground using a high-performance hydraulic hammer, and the soil is then pushed into the tube for examination.
In order to prevent the borehole from collapsing in on itself, if the ground is unstable, the hole is then lined with a steel tube.
Once the sample has been extracted, it is then logged by a trained and qualified engineer.
The sample tubes used in Windowless Sampling are usually 1m long and are available in various diameters.
The technique can be used to extract samples at depths of up to 10 metres, depending on factors such as soil type.
THE BENEFITS OF WINDOWLESS SAMPLING
Windowless Sampling offers a whole host of benefits over other types of sampling. Firstly, the technique offers a rapid assessment of soft soil conditions.
Secondly, because the machinery used to complete Windowless Sampling is relatively small and compact, it can easily be transported, making it ideal for sites with limited access and operating room.
During the process, the drilling rigs are mounted onto rubber tracks, meaning that disturbance is minimal.
This makes Windowless Sampling suitable for use on environmentally sensitive sites with restricted access, areas that are close up against walls or inside buildings, and those where it would typically be difficult to obtain samples.
What’s more, Windowless Sampling rigs can also be tracked up slopes, driven through standard domestic doorways, and, in areas where head-room or access are limited, hand-held equipment can also be used.
This method of sampling also minimises the potential for the cross-contamination of the soil samples during the drilling process.
However, it should be noted that this method of sampling is not designed for sampling or coring in hard rocks.
STANDARD PENETRATION TESTS (SPT)
Our highly skilled and experienced team are perfectly equipped to complete Standard Penetration Tests.
These in-situ dynamic penetration tests are designed to provide advanced technical information about the properties of the soil between a site.
During an SPT test, the sample tube can be driven into the ground up to 150 meters below the surface, allowing us to check the density of granular deposits.
This method also allows for the easy installation of Gas and Groundwater monitoring pipes.