A Cone Penetrometer is a technology (CPT for short) of sensors that are used to penetrate the strata of soils at a controlled rate,to determine the precise makeup of the contents of that earth, or water, etc. Cone Penetration results provide real-time information about the depth of bedrock, density and makeup of sub-soil and so on. A Cone Penetrometer typically resembles a solid steel rod about 1 foot in length, with a precise cone-shaped end. This cone is specifically designed for penetrating the strata of sub-soil layers encountered as it is pressed further into the earth.
Various sensors can be used in this technology. And the pressure of penetration can be in excess of 40,000 lbs./sq. inch when in operation.
The term CPT is more commonly used to describe "Cone Penetrometer Technology". CPT does not refer directly to Cone Penetrometer Testing, although one could argue the Technology and the process of testing with Cone Penetrometers are one and the same.
CPT results provide a cost-effective means to determine not only the composition of soils strata, but remarkably, the presence of foreign contaminants being searched for. It is far more cost effective because the test on site (or in-situ) provides results instantly, rather than the older technology of collecting soil samples, sending sample to a lab for investigation, and awaiting results that that process of course entails. A CPT Push Platform is used, in accordance with the depends of the terrain being tested, that pushes each CPT test down, samples and reports the results in real time, and continues to move on in a grid-like pattern over a large area.
Petroleum hydrocarbons are detectable using CPT - Cone Penetrometer Technology. As one sample a large area of terrain, the presence, amount, and makeup of petroleum hydrocarbons are mappable, and the changes of these contaminants over time are thus able to be monitored.
More information about Cone Penetrometers (Wikipedia)
Cone Penetrometers (Leading supplier of cone penetrometers.)
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