RAP Material Pretreatment Process Technology and Experimental Research

With the popularization of the concept of green environmental protection, the application of asphalt pavement recycled materials ( RAP ) in road construction has been paid more and more attention. In order to improve the utilization efficiency of RAP, this paper deeply studies the pretreatment process of 0 mm~10 mm RAP material, and constructs the application process of pretreatment-proportion-construction system. Through the combination of laboratory test and field test, the asphalt content test, Marshall test and construction quality test of RAP materials under different pretreatment process parameters were carried out to evaluate its application effect in ultra-thin overlay and thin overlay.In the application of ultra-thin overlay, the deviation between the measured value and the design value of the asphalt content of the pretreated RAP material is 1.38%, the water permeability coefficient of the test section is 600 ml/min and 533 ml/min, the thickness is 26 mm and 25 mm, and the flatness meets the standard requirements. In the thin layer overlay, the deviation of asphalt content of RAP material with 30% blending ratio is only 0.15%, and the Marshall test index is up to standard. The water permeability coefficients of the test section are 276 ml/min and 320 ml/min, respectively. The thickness is 35 mm and 36 mm, the degree of compaction is 96.8% and 97.3%, and the flatness is also up to standard.The research results show that by reasonably regulating the pretreatment process parameters, the regeneration effect of RAP can be significantly optimized, the quality and road performance of the mixture can be improved, and reliable technical support is provided for the efficient utilization of RAP.