The Research On Optimum Design Model Of Aggregate Grading For AC-13 Asphalt Mixture Based On High Temperature Performance

This paper uses AC-13 bituminous mixture, which is used much often in our country highway asphalt pavement surface layer, to be the asphalt mixture research type. In the present specification standard gradation scope AC-13, taking the Bailey coefficient ratiosCA , FAc and FAf as the gradation factors of the experimental, ten gradations are chose to conduct the experimental research.Through a lot of experiments indoor, the reorganization to the test result carried on, the relations among the Volume Index (VV ,VMA,VFA) of each gradation bituminous mixture and the Index ( MS , FL ) of Marshall experiments and the Hyperthermia Stability Index ( DS ,δ) as well as the effective thickness of the asphalt membrane, the powder rubber ratio FB and the relations between the volume percentage V g of the mineral aggregate and the Bailey coefficient ratio analyzed:①Basing this article experimental study analysis, this article recommends that the comparatively reasonable numeric area of CA is 0.4 ~ 0.65, FAc and FAf is 0.4 ~ 0.5;②To the bituminous mixture indexes , FAcmust be more remarkable than the other two Bailey coefficients ( FAc ratio and FAf ratio), in particular to the blend high temperature wheel rutting test, the dynamic stability turns to linear, as well as when FAc is smaller than 0.5, the relative deformation rate is also approximate line;③FAf affect remarkable to the bituminous mixture volume index, not so obviously to the bituminous mixtures stability, the flow value, the dynamic stability and the asphalt membrane, but extremely remarkable to the relative deformation rate of the high temperature stable influence.To these 10 gradation test result, using SPSS statistics software, taking the Bailey coefficient ratio as the independent variable, the bituminous mixture volume index (VV ,VMA,VFA) and Marshall Test Index ( MS,FL) and the high temperature stability index ( DS,δ) as well as the asphalt membrane effective thickness DA, the powder rubber ratio FB and the volume percentage V gas the dependent variable, to carry on the multiple regression analysis, and get the Bailey coefficient ratio and the bituminous mixture correspondence index regression equation. Setting up the establishment system of equations with the regressive equation, planning solution with the Excel software, taking the satisfied volume index and pavement performance as the restrict parameters , taking the high temperature stability as the objective function, solving to the return equation implementation optimization, extracting the Bailey coefficient value, figuring out the passing rate of each control particle size with the Bailey coefficient, then the optimization gradation with relatively good performance in high temperature can be determined. From the examination experiment of the optimize gradation, it can turn to that after optimized every performance index and volume index of the bituminous mixture satisfies the standard request. Compared with the ten kind of the bituminous mixture performance index in the original test, the high temperature performance all enhance prodigiously.