Effects of the high temperature and heavy load on the rutting resistance of cold-mix emulsified asphalt mixture

Abstract

Energy conservation and emission reduction have always been a concern. In the field of road engineering, the high-temperature paving of asphalt pavement causes a large amount of energy consumption and harmful gas emission. To resolve this, a new cold-mix SBS modified emulsified asphalt (S-CMA) mixture was developed and then systematically investigated in terms of a series of performance, including void ratio, Marshall stability, splitting strength, water stability and rutting performance, compared to the conventional hot mix asphalt (HMA) and warm mix asphalt (WMA) mixtures. Among them, the rutting performance of the above three mixtures subjected to various high temperatures and contact tire pressures (loads) and the mechanism of their differences were studied emphatically. In contrast to the HMA and WMA mixtures, the S-CMA mixture has much more excellent mechanical properties and rutting performance as well as comparable water stability. For the three mixtures, the degradations in rutting resistance with both increasing temperature and load follow a linear law while the increasing temperature and load reduce the sensitivity of rutting resistance of asphalt mixture to load and temperature, respectively. The rutting resistance is much more sensitive to temperature than load. Compared to the HMA and WMA mixtures, the S-CMA mixture shows a significantly lowest sensitivity in rutting resistance to both temperature and load. The excellent rutting resistance of the S-CMA mixture is mainly ascribed to the formation of the stronger spatial network structure and physical crosslink of asphalt binder due to the hydration reaction of cement and the formation of a lot of hydrogen bonds, respectively. Therefore, the S-CMA mixture can be used as a promising new pavement material with energy conservation and emission reduction.