Radar testing of structural concrete

Application of sub-surface impulse radar to durability and integrity assessment of concrete bridge decks and highway pavements has developed over many years. This experience has recently been successfully extended to a much wider range of applications related to structural concrete. Developments in commercially available field testing apparatus, including digital systems with colour display facilities, have facilitated major advances in signal processing and analysis of site results. Currently established applications include determination of major construction features; estimation of element thickness; location of reinforcing bars, voids, honeycombing, cracking, moisture and chloride contamination. These are all comparative in nature and can be achieved to varying degrees of reliability, but accurate sizing of buried features is more difficult. Other proposed applications including estimation of chloride concentrations and location of reinforcement corrosion require further investigation.