Emiliano Rustighi - Institute of Sound and Vibration Research, University of Southampton - Séminaire du LVA

Mapping the underworld (Imagerie acoustique des sous-sols)

The problems associated with inaccurate location of buried pipes and cables have been serious for many years and are getting worse as a result of increasing traffic congestion in the major urban areas. In response to this, a large multi-centre programme, Mapping the Underworld (MTU, www.mappingtheunderworld.ac.uk ), is being undertaken in the UK, dating back to 2004, to research a range of technologies that could be combined into a single device to accurately locate buried pipes and cables.
In my presentation I will present an acoustic method which uses seismic wave for the detection of buried object. Directional shear waves are generated at the ground surface and the subsequent reflections arriving at the ground surface detected and analysed. Cross-correlation functions between the measured ground velocities and a reference ground velocity measurement adjacent to the excitation are used to generate a cross-sectional image of the ground using a time domain stacking approach. The shear wave method has been successful at detecting both plastic and metal water pipes and air-filled metal pipes.
Finally I will present other areas of personal interest and some plan for my visit at LVA.