Study On Slow Release Mechanism And Long Term Evaluation Method Of Low Freezing Point Asphalt Mixture

The winter snow disaster road is the main factor restricting Chinese winter transportation efficiency and safety of life and property,in order to eliminate the influence caused by snow disaster,many research were carried out at home and abroad.Low freezing point of asphalt mixture is an effective way to alleviate the snow disaster in the winter.The present study for low freezing pavement mostly concentrated on road performance and de icing performance verification,few studies on the effective component of low freezing point diffusion mechanism of filler in asphalt mixture and long-term evaluation of low freezing point asphalt mixture method.Therefore,it is necessary to study the release characteristics,diffusion mechanism and long-term evaluation methods of effective components.Firstly,in accordance with the standard of asphalt mixture molding specimens,the specimens were cut,get the research object indoor research needs;selecting cumulative release concentration,single release concentration and residual effective components as evaluation index release characteristics,analyszing characteristics of of three indexes with time comprehensively;extracting asphalt type,asphalt types and temperature as the affecting factors of the release characteristics,analyzing the effect of different factors on the release characteristics of active ingredients.Secondly,by means of molecular dynamics simulation,establish the system of asphalt and effective components,to explore the characteristics of adsorption and diffusion on molecular scale.The binding energy,radial distribution function and diffusion coefficient at different temperatures and pressures were calculated.The influence of temperature,pressure and amount on the adsorption and diffusion characteristics of active components was analyzed.Finally,the relationship between bond stress analysis and effective component concentration,critical adhesion and critical concentration were obtained,combined with the release curve of effective component effective effect of indoor low freezing point of asphalt mixture,according to the historical rainfall situation of Harbin City,the effective indoor time converted into effective components of the actual pavement service time to complete evaluation of the long-term.The release properties of effective ingredients,the microscopic diffusion mechanism and long-term evaluation of low freezing point of asphalt mixture research methods,conclusions as research materials will snow provides a new basis and reference for chemical inhibition.