Non destructive tests to detect the integrity of steel anchors in corrosive environments

Metal-tensioned systems like bar or strand anchors may lose efficiency and eventually reach failure due to corrosion caused by aggressive ground condi tions or stray currents. Early recognition tests capable of highlighting the loss of performance would enable to undertake remediation before these effects become catastrophic. The paper analyses the efficiency of different non-invasive techniques adopted to assess the continui ty and the geometric shrinkage of metal bars. A review of the literature is initially made to illustrate potentials and defects of the different solutions providing a one-dimensional propagation of waves along slender elements. Then an experimental set-up is created in the laboratory to evaluate the effectiveness of a ultrasonic vibratory wave system wi th bench tests on bars of various geometrical and mechanical characteristics. Defects such as cross sectional reduction, artificially simulated on the bars, are highlighted by the analyses of the recorded signals.