Proposed Tests for Cold Recycling Balanced Mixture Design with Measured Impact of Varying Emulsion and Cement Contents

Abstract

Cold recycling is a cost-effective and sustainable rehabilitation technique. Proper mixture design and optimization in terms of emulsion and cement contents can be helpful to ensure satisfactory performance. A balanced mixture design approach for cold recycling is proposed. The indirect tensile asphalt cracking test (IDEAL-CT) performed at 25°C with a 100-mm-diameter gyratory mold compacted at 50 gyrations and 62-mm-high cylindrical specimens and a loading rate of 50 mm/min is used to assess the cracking resistance of cold recycling. The resulting cracking test index (CTI) can differentiate mixtures with varying emulsion and cement contents. A wheel tracking test performed at 60°C on cold recycling slabs is used to evaluate the rutting resistance. The cracking and rutting tests can be highly valuable for selecting optimum emulsion and cement contents. Setting proper CTI and dynamic stability (DS) limits can aid in achieving an optimum design.