Research On Mixing Ratio Design Of Rubber Granular Asphalt Mixture And Performance Under Freeze-thaw Cycle

In China,due to the winter ice and snow weather,many roads will appear snow and icing,and road icing affects traffic safety and is prone to traffic accidents.The rubber particle asphalt pavement,as a pavement with elastic deformation ability,can break the ice layer in a certain extent when the road freezes.At present,scholars have conducted a lot of research on the rubber particle asphalt pavement and found some defects in this kind of pavement.The most common problems are that the loose peeling disease of the road surface,and this disease becomes more and more obvious with the effect of the freeze-thaw cycle.In order to verify the impact of this problem on the rubber particle asphalt pavement,a large number of experiments have been carried out in this paper and the main research results are as follows:(1)Based on the optimized volume design method,an experimental design was carried out.The Marshall test results of the mixture under different rubber particle content conditions were compared and analyzed.It was found that with the increase of the amount of rubber particles,the optimal oil-to-stone ratio,voidage and flow value of the mixture increased,while the density and stability of the mixture decreased.(2)Based on performance tests of the original conventional high temperature,low temperature,anti-flying and anti-water damage,the performance tests of rubber granular asphalt mixtures under different modified asphalts after freeze-thaw cycles were carried out.It was found that the performance after the freeze-thaw cycle showed a downward trend,but basically met the technical requirements of the specification.When the high viscosity modified asphalt was used,the pavement performance of the mixture was better than that of SBS modified asphalt before or after freeze-thaw cycle.(3)With the rutting deicing test method,the deicing effects of rubber particles and ordinary asphalt mixtures under different ice layer thicknesses and the deicing effects of rubber particles asphalt mixtures after freeze-thaw cycles were evaluated.It was found that under the same ice thickness,the rubber granular asphalt mixture showed a better deicing effect,but still existed certain limitations.With the increase in the number of freeze-thaw cycles and the thickness of the ice layer,the crushing rate became smaller.Moreover,when the thickness of the ice layer exceeds 8mm,the deicing ability basically disappeared.