Impact of RAP classification on the road performance variability of recycled mixture

In order to control the variability of recycled asphalt pavement (RAP) and ensure the road performance of recycled mixture. The coefficient of variability (CV) was used to describe the variability of RAP, and the classification standard of RAP was determined by controlling primary control sieve. The research results showed that asphalt aggregate ratio and gradation of fine RAP have great variability. The primary control sieve for the classification of coarse RAP, fine RAP are 12mm and 5mm, respectively. When the separation of RAP into three stockpiles, the variability of asphalt aggregate ratio and gradation of RAP have been controlled effectively, especially the CV of passing rate at 4.75mm primary control sieve is decreased by more than 80%. It will help minimize the variability in recycled mixtures and provide a constructed recycled mixture with better performance.