Development Of The Ultra Low Noise Poroelastic Road Surface: The Findings Of The Persuade Project

A poroelastic road surface (PERS) consists of rubber granulates and stone aggregates, bound with an elastic resin, such as polyurethane. It does not contain bitumen. Thanks to its elasticity, porosity and texture, it is capable of yielding an unequalled noise reduction, typically 8 - 12 dB(A) with respect to reference dense asphalt concrete. Although already invented in 1979, some persistent problems, the most important being as durability, prevented the use of it for noise abatement. In 2009 the six year EU funded project PERSUADE started, aiming to develop a highly noise reducing, safe and affordable PERS with an acceptable durability. The approach of the PERSUADE consortium was at the same time holistic (all aspects of PERS were studied) and step-wise. It started with laboratory testing of mixes and adhesion to the sub layer. Then small scale pilot test tracks were constructed on parking lots and consequently full scale test tracks on real roads. An extensive monitoring program extracted as much as possible information from the test tracks. Many other relevant aspects, such as cost-benefit, fire safety, toxicity, sustainability, etc were thoroughly studied. This contribution outlines all the findings of the project and makes clear how one go further with this technology.