摘要
Chronic exposure to environmental noise is recognized as a leading public-health hazard, second only to air pollution across Europe.Road traffic, railways, aircraft, and industrial machinery routinely generate sound levels that exceed World Health Organization guidelines, costing an estimated 1.6 million healthy life-years annually through sleep disturbance, cardiovascular disease, and cognitive impairment (World Health Organization, 2018).This paper reviews engineering strategies for mitigating such noise, emphasizing recent advances in passive sound-absorption materials and the computational models used to optimize them.After surveying the underlying physics of sound propagation and human-weighted noise metrics, we compare conventional porous absorbers with emerging solutions such as micro-perforated panels, graded 3-D-printed lattices, and low-frequency acoustic metamaterials.Finite-element, boundary-element, statistical-energy analysis, and machine-learning surrogate techniques are discussed in the context of absorber design.Four case studies-an industrial powder-mill enclosure, an entertainment-venue retrofit, a hospital HVAC plantroom, and a pilot metamaterial highway barrier-illustrate practical gains of 5-10 dB(A) through tailored absorption-plus-insulation strategies.Finally, we outline future directions, including adaptive tunable absorbers, hybrid active-passive systems, AI-driven noise-monitoring networks, and policy measures for sustainable urban soundscapes.The analysis shows that integrating advanced materials with data-centric optimization can substantially reduce environmental and occupational noise without compromising economic growth or urban density.