Analysis of coherent surface wave dispersion and attenuation for non-destructive testing of concrete

Mathieu Chekroun (1) , Loïc Le Marrec (2) , Odile Abraham (3) , Olivier Durand (3) , Géraldine Villain (3)

1 EDF - EDF
2 IRMAR - Institut de Recherche Mathématique de Rennes
3 LCPC/RMS - Division Reconnaissance et Mécanique des Sols

Rayleigh waves measurements are used to characterise cover concrete and mortar in the frequency range 60180 kHz. At these frequencies, the wavelength is comparable to the size of the aggregates, and waves propagate in a multiple scattering regime. Acquired signals are then difficult to interpret due to an important incoherent part. The method proposed here is the study of the coherent waves, obtained by averaging signals over several configurations of disorder. Coherent waves give information on an equivalent homogeneous medium. To acquire a large amount of measurements with accuracy, an optimised piezoelectric source is used with a laser interferometer for reception. Adapted signal processing technique are presented to evaluate the coherent phase and group velocities and also the coherent attenuation parameter.The sensitivity of these three parameters with the properties of concrete is discussed, as well as the necessity to use coherent waves to obtain accurate results.

Mots clés: concrete; Rayleigh waves; ultrasounds; laser interferometer; scattering; effective 8 medium; dispersion; attenuation; signal processing 9

Mots clés: ONDE DE RAYLEIGH; BETON; TRAITEMENT DU SIGNAL; INTERFEROMETRIE

Domaines: Traitement du signal et de l'image [eess.SP]; Matériaux; Mécanique des matériaux [physics.class-ph]

Mathieu Chekroun, Loïc Le Marrec, Odile Abraham, Olivier Durand, Géraldine Villain. Analysis of coherent surface wave dispersion and attenuation for non-destructive testing of concrete. Ultrasonics, 2009, 49 (8), pp 743-751. ⟨10.1016/j.ultras.2009.05.006⟩. ⟨hal-00436273⟩