RADAR INSPECTION OF CIVIL ENGINEERING STRUCTURES

Seismic radar has been used as a geophysical tool for mineral exploration since the 1970's. Ground probing radar has been used in many applications world-wide. In the United Kingdom, radar became an established tool in the investigation of a sub-standard block of flats at Ronan Point in 1984. An advantage of radar is that it can be used to scan whole areas at an acceptable speed. However, despite the potential of radar, the civil engineering community in the UK has been slow to adopt the technology. This is partly because some claims about the capabilities of radar have been overstated, and also because the data currently generated can be difficult for the non-specialist to understand. The work (the authors all work at the National NDT Centre at Harwell) has used two approaches to address these specific problems. First, signal processing combined with a well-defined inspection procedure has been used to produce clearer images. Second, modelling of assumed subsurface structure is carried out to yield theoretical images which can be used to optimise inspections and aid in interpretation of real datafiles. The advantages to typical radar data are demonstrated by example. (A) For the covering abstract see IRRD 861706.