Mechanical properties estimation of standard and lightweight concrete through the elastic waves propagation

Even if treated in the literature and carried out through several methods, the reliable estimation of the effective elastic properties of random media is still an open problem. Homogenization approaches, based on the study of a representative volume element, are generally used with analytical or numerical models. When considering real materials, one of the most common techniques for the estimation of effective elastic properties is based on the analysis of elastic waves propagation. In this work, the first results of a comparison between the elastic properties estimation obtained by ultrasonic tests and impact tests applied to different kinds of materials are illustrated. In particular, two materials were studied: the first is a standard concrete with small-size aggregates and the latter is a lightweight concrete containing a 50% volume ratio of EPS spherical shape particles. Direct and indirect tests were carried out on both materials and, using a probabilistic approach applied to the formulation of P- and R-waves, the elastic properties of the equivalent homogenized continuum were estimated also considering confidence intervals.