Superior cold rolled asphalt mixtures using supplementary cementations materials

Abstract

Hot Rolled Asphalt (HRA), which is a gap-graded mixture, is extensively used for surfacing major roads in the UK because it provides a dense, impervious layer, resulting in a weather-resistant durable surface able to endure the demands of modern traffic loads and providing good resistance to fatigue cracking.This paper describes a laboratory study on the production of new, superior, cold Bitumen Emulsion Mixtures (BEMs) with the same gradation used with conventional HRA mixtures and collectively incorporating different types of supplementary cementitious materials (SCM) instead of the conventional mineral filler. Accordingly, two ternary blended fillers termed as TBF-1 and TBF-2, have been blended from different SCMs and optimised to replace the conventional mineral filler.To develop the gap-graded Cold Rolled Asphalt (CRA) mixtures evaluation of stiffness modulus, creep performance and fatigue testing was used to assess the mechanical properties while stiffness modulus ratio was used to investigate the water sensitivity.The study concluded that there is a substantial improvement in the mechanical properties and water sensitivity of CRA containing TBF-1 and TBF-2. Also, the superior CRA mixtures produced showed a significant lower thermal sensitivity than conventional HRA. More remarkably, the new CRA were found to be comparable with the conventional HRA after a very short curing time (after 4h).