Metaconcrete is an architectured composite material obtained by embedding designed aggregates within a cementitious matrix to enhance its dynamic performance, as originally proposed in [1] Due to the inherent variability in aggregate distributions, metaconcrete can be naturally interpreted as a random heterogeneous metamaterial, whose dynamic response requires a statistical description. In this work, the dynamic behavior of metaconcrete is investigated through a stochastic spectral analysis based on ensembles of randomly generated microstructural realizations. Bloch–Floquet eigenvalue analyses are performed on statistical volume elements to compute the density of states (DOS) and the integrated density of states (IDS) in physical frequency space. A convergence criterion based on confidence intervals and region-of-interest selection is introduced to determine the minimum number of realizations needed for reliable spectral estimates. The analysis provides a basis for the identification of effective, frequency-dependent elastic properties, accounting for the viscoelastic nature of the composite under dynamic loading. The proposed framework is related to recent studies on wave propagation and dynamic tunability in architectured and quasi-periodic metamaterials [2] and extends these concepts to stochastic metaconcrete systems. The results contribute to the dynamic homogenization and design of metaconcrete for wave control and vibration mitigation applications. REFERENCES [1] Mitchell, S.J., Pandolfi, A. and Ortiz, M. Metaconcrete: designed aggregates to enhance dynamic performance. Journal of the Mechanics and Physics of Solids, 65, pp.69-81, 2014 . [2] Bacigalupo, A., De Bellis, M.L. and Vasta, M. Design of tunable hierarchical waveguides based on Fibonacci-like microstructure. International Journal of Mechanical Sciences, 224, p.107280, 2022.