A new sustainable material for in-situ absorption in noise barrier walls

Perforated macrocellular foams produced using recyclable polyolefin resins have existed as acoustic absorption panels for almost 20 years. They have broad acoustic absorption with good resistance to moisture, salt and UV exposure. Adoption of In-Situ sound reflection standards, in the Rail and Road noise barrier industry; along with renewed focus on sustainable design has led to renewed interest in this technology. Traditional foam panel formats did not attain acceptable in-situ sound reflection performance. The purpose of this study was to evaluate an improved structure of foam to the industry norms required of absorptive components of the noise barrier wall; and then subject this to a lifecycle analysis. A new structure showed good reflection results in-situ, using a reduced mass of raw material. The novel panel was evaluated to a range of acoustic and mechanical testing standards to assess suitability for adoption in Noise Barrier Wall applications. The material was subsequently subjected to lifecycle analysis and the resulting product issued with an environmental product declaration. This paper concludes that the new material is well suited to widespread use in in-situ category A3 noise barrier walls.