Numerical time-domain simulation of diffusive ultrasound in concrete.

Certain aspects of diffusive ultrasound fields in concrete are still unknown and thus, systematic parameter studies using numerical time-domain simulations of the ultrasonic propagation process could lead to further insights into theoretical and experimental questions. In the present paper, the elastodynamic finite integration technique (EFIT) is used to simulate a diffusive reverberation measurement at a concrete specimen taking aggregates, pores, and viscoelastic damping explicitly into account. The numerical results for dissipation and diffusivity are compared with theoretical models. Moreover, the influence of air-filled pores in the cement matrix is demonstrated.