Properties of cold mix asphalt mixtures with reclaimed granular aggregate from crushed PCC pavement

The current Portland cement concrete (PCC) pavement rubblization process cannot remove debilitating mastic which is composed of asphalt and particles (<0.075 mm), nor can guarantee the optimum asphalt content as well as even distribution of the asphalt mixture. The weakest link in the process has significantly influenced the structural strength and the ability of resisting asphalt overlay deformation. In this paper, the reclaimed granular aggregates (RGA) from crushed PCC pavement are collected and added into cold mix asphalt mixture using emulsified asphalt. By evaluating the properties of the recycled mixture, optimized method can be obtained. Results shows that with 5% of emulsified asphalt content in the recycled mixture, these properties can be enhanced. The cold recycled mixture shows higher mechanical strength, better resistance to high temperature and moisture-induced damage, and improves uniformity of the pavement structure. Furthermore, demonstration in a test section shows that this design process can provide a suitable flexible base for the asphalt overlay with a 34% reduction in materials consumption which indicates the economic advantage of this design in construction practices.