LIFE CYCLE INVENTORY OF RECLAIMED ASPHALT PAVEMENT

Regarding general increasing environmental cares and in order to meet the new 2002 French legislation dealing with landfill, recycling is going to increase. Thus, only final waste products will be allowed in municipal waste disposals. An experimental site study of road building, recycling the old pavement has then been performed. The aim of this study was, in the Life Cycle Analysis (LCM) framework, to present the environmental inventory analysis of asphalt road building based on the recycling rate, involving the choice of an optimised recycling rate. Attention has been focused on a single asphalt layer (the binding course) and resource consumption, airborne emissions and waste generation. Specific measurements have been performed during a data collection phase which was decomposed using the following sub-systems: raw material supply, transport, asphalt production and road building. An experiment was carried out in 2001, on a heavy traffic French road, starting from the selective demolition of the pavement and re-use of reclaimed asphalt pavement (RAP). Both consumptions and releases were measured for four different recycling rates (0, 10, 20 and 30%). This experiment consisted in milling the wear course and binder courses of four identical road sections, in order to produce properly conditioned reclaimed asphalt. The aggregates were directly recycled into a hot mix asphalt plant, for new pavement realisation at the road location. According to the current ISO 14040 standards, the results were gathered for the functional unit chosen, into a single list of inventory for life cycle evaluation with the recycling rate. A comparison between the recycling rates is thus proposed and discussed. For the covering abstract see ITRD E121480.