Research On Material Composition And Performance Of Anti-sliding Surface Layer In Asphalt Pavement

Aiming at the problem of insufficient skidding resistance of asphalt pavement,the influence of mineral aggregate gradation,adhesive materials and macroscopic texture on the anti skid performance of pavement is emphatically analyzed,and the anti skid performance of asphalt pavement is explored.A test method of anti skid performance and a new anti skid material is put forward to improve asphalt pavement.It is of great significance to improve the skid resistance of asphalt pavement.The main contents are as follows:(1)Four influence factors that contributed to the anti-slide performance of asphalt pavement were mainly researched,including the mineral property,the adhesive materials,the mineral aggregate gradation and the external environment factors.The main factors were clarified,which can provide theoretical support for the design of the high anti-slide surface layer.(2)In order to improve the anti-slide performance and durability of the anti-slide surface layer,a new type of anti-slide surface gradation was proposed by utilizing the method of uniform design and the theory of volume design method.Several suitable evaluation indexes were selected as well.Moreover,the grey system theory was used to analyze the influence degree of each grade mineral material on the evaluation index of gradation and the influence of the mineral material grade on the actual project was further analyzed by regression method.(3)The preparation technologies of three kinds of adhesive materials,named as high viscosity SBS modified asphalt,high viscosity SBS epoxy bitumen and bentonite high viscosity SBS epoxy asphalt were studied and their comprehensive performance were researched through designed experiments.Indoor pull-out tests aiming at different composite materials were carried out and the optimum dosage of admixtures was determined using the proposed fracture energy evaluation index.Moreover,these three kinds of adhesive materials were evaluated and the recommended formulation of high anti-slide surface layer was obtained.(4)A macroscopic texture testing method for pavement was proposed on the basis of industrial close range photogrammetry,and the modeling process and evaluation system based on photogrammetry were established.The feasibility to extract macroscopic texture of the pavement from established model was also verified.Based on researches on existed evaluation indexes of the macroscopic texture of the pavement at home and abroad,the correlation fitting relationships between each index and the relative performance of anti-slide tested specimen were drawn,and evaluation indexes with better feasibility were obtained and then applied to evaluate pavement's anti-slide performance.(5)The basic road performance of the design gradation was verified,which demonstrated fairly well high temperature stability,water stability and abrasion resistance,which can meet the requirements of specification.To improve the anti-slide durability of surface layer,the steel slag was first mixed in the anti-slide surface of asphalt pavement.The relationship between the amount of steel slag and the anti-slide durability of pavement was studied.The decay of the anti-slide performance of high anti-slide surface layer was emphatically studied through accelerated wear experiment while the anti-slide performance was evaluated adopting the anti-slide indexes and the macroscopic texture indexes.In the end,the synergistic decay model of slide resistance and macroscopic texture was proposed and the anti-slide performance of pavement under random factors was predicted.