Building blocks for a best practice guide on cold in-place recycling

Abstract

In order to facilitate the sharing of national experiences on dismantling and recycling of road and road related materials, the three-year Direct-Mat project was initiated in January 2009, within the EU 7th Framework Program Transport. The project addresses the recycling of unbound, hydraulically-bound and asphalt road materials as well as other materials not commonly recycled in roads. Among these technologies, this paper focuses specifically on cold in-place recycling, which is considered a very promising technique from the environmental point of view, since it allows for the reuse of reclaimed asphalt as well as for energy savings and reduction of harmful emissions. The results obtained so far have shown that some European countries have already acquired experience with cold in-place recycling, but this has largely been done in isolation. Therefore, the practice at national level can differ significantly from one European country to another, and although some research has already been done, further efforts should be made in order to optimize the use of cold in-place recycling. In the framework of this project a Best Practice Guide (BPG) was prepared. This was aimed at issuing recommendations for cold in-place pavement recycling in order to offer the highest added value. This paper highlights some recommendations included in the BPG on the following topics: pavement characterization, mix design, production, application, curing process, mix performance. This paper is based on the work carried out within Direct-Mat project, which involved partners from 15 participating countries. Therefore, it reflects the views of its participating members.