This report describes the first of three experimental installations of open-graded friction course (OGFC) “quieter pavements” designed to reduce the noise generated at the tire/pavement interface. Experimental sections of OGFC were built using asphalt rubber (AR) and styrene-butadiene-styrene (SBS) polymer modified asphalt binders. A section of conventional hot mix asphalt (HMA) served as the control section for the two experimental sections.
The noise level of the OGFC-AR test section was audibly quieter than the HMA control section for only a period of four months after construction. The OGFC-SBS section was not initially audibly quieter than the HMA but attained that level of noise reduction for brief periods of time that extended to fourteen months after construction. The OGFC test sections were prone to excessive raveling and rutting, especially the OGFC-AR test section which in places wore through to the underlying pavement. The OGFC-AR test section was removed in the fall of 2010 after only four years of service due to safety concerns with vehicles having to cross the deep ruts during shifts of traffic necessary for the construction of new ramps for the Alderwood Mall interchange.
Open graded friction course quieter pavements are not recommended for use in Washington State due to the short duration of their noise mitigation properties and higher life cycle cost.