Wave propagation based methods for investigation of concrete and masonry architectural members

Methods based on acoustic wave propagation are suitable for local damage detection and for the evaluation of structural elements made of concrete or masonry. Ultrasonic pulse velocity and attenuation measurements are effective when analysing dense materials and small or medium size elements whilst methods based on shock excitation - thus employing higher transmission energy - are more suitable for highly absorptive materials as thick concrete and masonry sections. After an introduction to some of these methods, the paper compares example data from two laboratory concrete specimens containing simulated defects such as voids and cracks. The ability of different non-destructive wave propagation methods in gaining section information and detecting defects is discussed in view of the diagnosis and conservation of cultural heritage.