Parametric Design and Assessment of 3D Printable Open Noise Barrier: Device Customization to Protect Buildings from Train Brake Noise

Three-dimensional (3D) printing applied in architectural engineering is profoundly changing building technologies and construction processes. Indeed, the wide scope of metamaterials and components manufactured with 3D printing provides unprecedented adaptability and customizability in construction. One of the promising applications of such novel technology concerns metamaterial noise barriers that protect buildings from environmental noise. More specifically, sonic crystal noise barriers (SCNBs) are effective solutions with good sound insulation characteristics (with the advantage of letting air/light pass through). Conversely, the limitations of SCNB are related to their design and manufacturing (new complex design approaches are required to maximize the performance of such devices). To overcome such drawbacks, this research proposes a novel methodological approach to design and customize the topology of SCNBs made achievable with additive manufacturing. First, parametric modeling affords design flexibility and adaptability. Second, iterative performance simulations are set to adjust parameters considering target frequencies. Third, 3D printing allows the prototyping of customized barriers. The methodology is applied to the case of train brake noise. A novel SCNB is designed, simulated, and prototyped through 3D-printing technology. Finally, experimental validation is executed according to current international standards.