Experimental Research On CRP-SBS(SBR) Composite Modified Asphalt In Plant Mixing Heat Regeneration

At present,the construction of China’s highway network has become more and more perfect,and a large number of existing roads are in urgent need of repair and maintenance.As one of the key technologies for road maintenance,pavement regeneration technology has obvious advantages in achieving material recycling,environmental protection,and cost reduction.In this paper,CRP modifier is combined with SBS and SBR to improve the performance of recycled asphalt mixture,and further verifies the applicability of domestic waste plastic in the asphalt mixture regeneration process,play a certain role in promoting the development of road recycling technology.The main work and research results are as follows:(1)In the research on the modification process of CRP-SBS and CRP-SBR composite modified asphalt,the influence of various factors on the performance of composite modified asphalt was analyzed by orthogonal test.Further improved the preparation process of CRP-SBS and CRP-SBR composite modified asphalt.(2)Under the observation of the fluorescence microscope,the SBR modifier is more evenly and saturated in the matrix asphalt,and the SBS modifier is evenly distributed in the matrix asphalt,both CRP-SBS composite modified asphalt and CRP / SBR composite modified asphalt have formed a stable three-dimensional network structure.CRP modifier combined with SBR modifier and SBS modifier plays a complementary role in performance advantages,and CRP modifier reduces the blending amount of SBR modifier and SBS modifier,the performance and economic benefits of CRP-SBS and CRP-SBR composite modified asphalt have been fully reflected.(3)Through the analysis of the coefficient of variation of each performance of the RAP material,it is concluded that each basic property of the RAP material meets the technical specifications of the hot mixed asphalt mixture in the plant,and the best dosage of regenerant is 5% through the performance design method.Through planning and accumulating method,40% is selected as the proportion of old material,and four types of modified asphalt are determined in six forms(SBS modified asphalt + regenerant,SBR modified asphalt + regenerant,CRP-SBS composite modified asphalt,CRP-SBR composite modified asphalt,CRP-SBS composite modified asphalt + regenerant,CRPSBR composite modified asphalt + regenerant)the best oil-rock ratio of the regenerated mixture.(4)The high-temperature performance,water stability and low-temperature performance of six types of recycled mixtures were compared and studied.The research shows that the recycled materials of CRP-SBS,CRP-SBR composite modified asphalt+ regenerant are better than the comprehensive road performance of SBS modified asphalt+ regenerant regenerated material,SBR modified asphalt + regenerated material regenerated material.Therefore,it is recommended to use CRP-SBR composite modified asphalt + regenerant and CRP-SBS composite modified asphalt + regenerant in the engineering practice of plant heat recovery.(5)From the perspective of economic and social benefits,the CRP composite modified asphalt reclaimed material is analyzed.The reclaimed material of CRP-SBS composite modified asphalt + regenerant required for the 1Km bottom layer test section is more than 30,000 yuan lower than the cost of SBS modified asphalt + regenerated material,CRP-SBR composite modified asphalt + regenerative recycled material has reduced the cost by more than 20,000 compared to SBR modified asphalt + regenerated material.It shows that CRP-SBS,CRP-SBR composite modified asphalt reclaimed material has very significant economic benefits.At the same time,CRP modifiers reduce the threat of domestic waste to the environment,and the regeneration of waste pavement materials reduces the damage to the environment,which has very significant social benefits.