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Description
Sonic Crystals (SCs) offer a promising alternative to traditional noise barriers through the creation of spectral band gaps. However, the performance of rigid scatterers is often limited by narrow attenuation zones. This study investigates the enhancement of SC barriers by utilizing a novel porous concrete matrix modified with recycled rubber shreds or cork powder.Initially, the acoustic properties of the mixtures were characterized via impedance tube measurements, revealing that rubber additives shift the absorption peak toward higher frequencies, while cork powder significantly broadens the absorption bandwidth. These findings were then applied to a case study of a modular SC barrier. Numerical simulations performed after laboratory measurements of the new mixtures, from which equivalent fluid parameters were obtained, demonstrate that scatterers composed of modified porous concrete provide a synergistic effect: the periodic arrangement maintains Bragg interference, while the intrinsic material absorption complements the insertion loss spectrum. The results indicate that cork-modified scatterers are particularly effective for broadband urban noise, while rubber-modified composites allow for targeted attenuation. This research highlights the potential of functionalized cement-based composites as high-performance, sustainable noise control structures.