Research On Performance Of Waste Crumb Rubber Modified Asphalt And The Mixture

The inexorable development of automobile industry has worsened the deposition of waste tire. An increasing number of countries are paying attention to the addition of waste crumb rubber to asphalt binders.First of all, this paper selected90#base asphalt as the object based on the environmental and local properties of Heilongjiang Province. Three commonly used index—penetration, ductility, softening point—and elastic recovery and rotation viscosity have been chosen as the technology and performance indexes. An orthogonal design method was done to analysis the effect of powder content, power mesh, mixing time and mixing temperature on the performance characteristics of waste crumb rubber modified asphalt. Test results indicated that powder content is the main influence factor, power mesh is a secondary consideration, and that the optimal powder content is18%; the optimal power mesh is80mesh; the optimal mixing temperature is180℃; the optimal mixing time is60min.Furthermore, storage time and temperature contribute greatly to the stability of rubberized asphalt. This paper separately tests the variations of the performance of rubberized asphalt. Experimental results show that the optimal storage temperature is170℃-180℃, storage time should be held within a range of9h.Additionally, in order to evaluate the paving performance of rubberized asphalt mixtures, three kinds of mixtures—AR-AC16, SBS-AC-16, Base-AC16—are designed. AR-AC16used Gap Type which proposed by Arizona, and SBS-AC16, Base-AC16used S Type. To evaluate the rutting resistance performance, the low temperature cracking resistance and the water stable ability of these mixtures, the wheel track test, the low temperature bend test, the immerse Marshall Experiment and the freezing thawing split test were performed. It was found that CRM modified mixtures is superior to conventional unmodified mixtures.At the end of this paper, the analysis of the economic benefits and environmental benefits of rubberized asphalt was conducted. The cost of rubberized asphalt is lower than SBS. This application brings about huge environmental benefits due to its preservation of natural environment, the utilization of wastes and the decrease of pavement noise.