Research On The Performance Of Interlayer Tack Coat Materials For Asphalt Surface

The quality of the combination of asphalt pavement layers is an important factor affecting the service life of the pavement.With the rapid growth of my country’s economy,my country’s highway traffic is developing towards the trend of "large flow,high speed,heavy load,and channelization".However,some asphalt soon after the pavement was opened to traffic,cutting slippage,cracking,folding and other diseases appeared.The reason is the insufficient interlayer adhesion.Therefore,it is necessary to study the interlayer adhesion of asphalt pavement.The shear stress of the asphalt pavement structure was analyzed by ABAQUS finite element software firstly,and the key factor affecting the asphalt pavement interlayer shear stress was concluded.Based on the finite element theoretical calculations,some corresponding requirements are proposed about the interlayer shear strength of different road sections.Afterwards,in order to solve the problem of insufficient bonding performance of tack coat materials,the performance of trackless modified asphalt was studied.The basic properties of modified asphalt were studied through three indicators test and Brookfield viscosity test,and combined with dynamic-shear rheology test and curved beam rheology test to determine the optimal content of modifier,And then through infrared spectrum analysis,scanning electron microscopy test,four-component analysis test,and combined with dynamic shear rheology test and curved beam rheology test to determine the optimal content of modifier,And then through infrared spectrum analysis,scanning electron microscopy test,four-component analysis test,the modifier’s mechanism of action was revealed.Finally,the best content of modifier was determined by direct shear test and pull-off test when the modified asphalt is used in the adhesive layer,and perform the bonding performance with ordinary hot asphalt,ordinary emulsified asphalt,and SBR modified emulsified asphalt were compared and analyzed.The results of the study show that,combining economy and bonding performance improvement effect,the optimal content of the modifier is 8%,and the modified asphalt has a better hightemperature lifting effect and suitable low-temperature performance at this content.The addition of the modifier can absorb a part of the saturated components in the asphalt,thereby forming a stable and non-segregating modified asphalt solution.When the temperature drops below the melting point of the modifier,it crystallizes out together with the light components in the asphalt adsorbed by it,forming a stable crystal network structure,which not only locks the light components,but also hinders other components.The movement of intermoleculars increases the viscosity and strength of the asphalt.Moreover,the improver has a rough surface and can be combined with the asphalt better.Comparative analysis of the bonding performance with ordinary hot asphalt,ordinary emulsified asphalt and SBR modified emulsified asphalt shows that the modified asphalt has excellent bonding properties.Finally,relying on the new construction of Binhu West Road in Changde City,the test road was paved,and the interlayer shear test was carried out on the core sample,which showed that the adhesive layer modified asphalt has good bonding performance.At the same time,the modified asphalt is in the actual construction process.It can be sprayed evenly at a temperature of 130℃,and it shows excellent trackless performance and has good application and promotion value.