Traffi c-speed ground penetrating radar surveys are now an accepted and widely used tool for investigating the sub-surface condition and make-up of a road, says Impulse Geophysics project manager Mark Walshe.
But traditionally, this meant regular cores had to be taken along the route. 'Our latest development is that we don't need the core information to calibrate the data, ' he says.
The technique is now reliable enough to convince clients, says Walshe, and it has proved particularly useful in avoiding lane closures during work for Transport for London.
The rm has been accredited by the Highways Agency, which holds performance trials. There are mandatory test elements covering traffic speed surveys, but Impulse Geophysics has also passed an optional part in the absence of core calibration information.
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