Study On The Effect And Mechanism Of Road Snow Melting Agent On Asphalt

The use of snow melting de-icing agents causes the decline of asphalt pavement performance.In order to analyze the impact and mechanism of road snow melting agents on asphalt,the paper selects three kinds of organic snow melting agents A₃N,A₂C,A₂A and traditional chloride salts,snow melting agent was formulated to 20%concentration to conducting static soaking corrosion test of matrix asphalt and SBS modified asphalt.Water immersion was set as control under test which period is six weeks,and 7days is a cycle.The change of three main indexes,brinell viscosity,complex shear modulus,rutting factor,fatigue factor,and phase angle was measured to analyze the effect of snow melting agent on asphalt performance.Penetration and rut factor of asphalt were non-linear fitted by Verhulst model and index function.Through observation of surface characteristics,fluorescence microscopy and infrared spectroscopy,The influence and action mechanism of snow melting agent on the macro and micro structure and components of asphalt was analyzed and explored.In order to analyze the penetration of inorganic ions in the solution of snow melting agent,a constant temperature closed penetration test was designed,and the change of cation concentration was detected by ICP-AES.Based on Verhulst model,the cation diffusion was quantified,and its transmission mechanism and law in asphalt were investigated.Based on Fick’s law,a cation permeability model was established and the concentration distribution function was derived to explore the concentration distribution of adsorbed cations in asphalt.The results show that the low-temperature performance and aging property of asphalt are weakened after immersion corrosion,A₂C,water,and chloride salts can improve the high-temperature performance of asphalt;The penetration of salt ions will change the rheological shear performance of asphalt,increase the complex shear modulus,rutting factor and fatigue factor,and reduce the phase angle;Organic components in A₃N,A₂C and A₂A can be similarly miscible with asphalt,which has a significant impact on the surface characteristics and microstructure of asphalt;After soaking,the light component of asphalt moved to the heavy component;the diffusion of cations to asphalt is physical infiltration,and the change of concentration conforms to Verhulst model;Fick binary concentration function could better match the change of adsorption capacity of cation.