Study On The Performance Of High Modulus Asphalt Mixture Under Different Design

Rutting of the highway road is more and more serious in our country at present. In the road maintenance, the thin surface layer thickness must have enough bearing capacity, while the traditional asphalt mixture can not meet, so we need to develop a new type of high modulus asphalt mixture. Using Bisar software to predict The surface layer modulus to the change trend of main mechanical indexes of pavement structure, with the increase of resilience modulus in the surface layer, the asphalt layer bottom shear stress, tensile stress at the bottom of layer and the tensile strain decreases, asphalt pavement performance can be effectively improved.Correlation analysis was carried out on the performance of asphalt rheological indexes and asphalt mixture rutting factor, the variation of dynamic modulus test of DSR asphalt and asphalt mixture rutting factor have great differences, is not directly connected with the anti rutting performance of asphalt mixture, the apparent viscosity and dynamic viscosity, high viscosity asphalt binder can improve the asphalt mixture temperature stability.This paper analyses specifically the differences and characteristics in the French high modulus commonly used using performance index as the goal,the Marshall design method using volume index as the goal, American Superpave design method. The French high modulus of asphalt mixture design method is different from the US, compared with the design method, has its unique advantages, the methods in this paper commonly refer to the French high modulus asphalt mixing design.according to the French high modulus design system.choose the EME-14mixture applicable to the selected layer, using the matrix asphalt of different grade, respectively, No.20, No.50, No.70asphalt and No.70+high modulus additive, related to the abundance coefficient, asphalt weight is5.6%. In the same grade, analysis the effects of different asphalt on asphalt high temperature stability performance, dynamic modulus, fatigue performance. Using low grade asphalt has the higher temperature stability of asphalt mixture than the simple addition of high modulus effect, and the temperature performance for EME-14mixture using No.70asphalt is not good:by four point bending fatigue test results, the use of low grade asphalt can improve the anti fatigue performance,but the mixture specimen is very fragile, compressive ability is poor, cannot afford large strain level; dynamic modulus master curve shows that the dynamic modulus values decreased with the increase of temperature, EME-14asphalt mixture using20asphalt has the higher dynamic modulus than the other three kinds of asphalt mixture1, additive can improve the modulus value, but the effect is limited. The use of the low-grade asphalt can improve asphalt mixture dynamic modulus values. Correlation analysis between the mechanical properties and high temperature properties of asphalt mixture, dynamic modulus values can not fully reflect the anti rutting performance of asphalt mixture, compared with modulus and phase angle, rut factor relative G*/sinφ has better evaluation material properties.