ATTENUATION AND DISPERSION OF ELASTIC-WAVES IN MULTIPHASE MATERIALS

The attenuation and dispersion of elastic waves in multi-phase materials such as granite, cement, mortar and concrete have been evaluated by the point-source/point-receiver technique with glass capillary breaking as an ideal source and a calibrated pin-type transducer as an ideal detector. The magnitude and phase spectrum from the Fourier analysis of the velocity signal gave attenuation and dispersion of the materials respectively, and the frequency dependence was also obtained in a single experiment. The sequence for attenuation was mortar, cement, granite and concrete; however, that for dispersion was cement, mortar, granite and concrete in increasing order. The difference in resonant frequency spectra of mortar and concrete blocks was explained in terms of the measured attenuation and dispersion.