| The interface interaction of asphalt and aggregate is the decisive factor to form the structure ofasphalt mixture.It is not only relete to the strength of the asphalt mixture, temperature stability, aging rate,but also directly determines the size of the adhesion of asphalt and aggregate. To further explore the studyof asphalt/aggregate interface interaction mechanism, in order to improve the asphalt/aggregateinterfacial properties, this paper analysis of the physical and chemical properties of the aggregate impacton the performance of asphalt/aggregate interface. From the experimental point of view, this paper studiesthe main chemical components of the aggregate, the aggregate surface texture features and the aggregatesurface free energy characteristics.For aggregate of chemical composition of characteristics, the single of chemical constituents hasbeen investigated through DSR experiment. Silicon oxide,ferric oxide,alumina oxide,calcium oxide andmagnesium oxide of the highest purity are used to study the aggregate of chemical compositions on theasphalt/aggregate interface interaction effects. K.Ziegel-B is chosen as evaluation indexes to analy thedynamic shear rheological experiment results and reveal the aggregate of major oxygen compounds to thehigh temperature of bitumen performance and the change rule of interaction. In the five differents nt ofasphalt mastics, magnesium oxide and ferric oxide powder play the role of significant, two of the asphaltmastics by adding magnesium oxide and ferric oxide powder have large K.Ziegel-B value, which indicatedthe interface bond properties are best; The asphalt mastic of adding silicon oxide’s K.Ziegel-B valuesignificantly lower than the other four kinds of asphalt mastics, which indicated this kind asphalt masticthe interface bond properties is worst; the two kinds of asphalt mastics by adding alumina oxide andcalcium oxide power’s K.Ziegel-B value place in the middle, which indicated the two asphalt masticsinterface bond properties are generally.For aggregate of surface texture characteristics, fractal theory is used to represent the aggregate ofsurface texture characteristics. Matlab procedure of projection covered method has been made to estimatethe three different aggregates’ the fractal dimension of Ds, compared to the same size different mineralaggregates’ fractal dimension, particle size of9.5mm mineral aggregate, diabase＞basalt＞limestone;Particle size of13.2mm mineral aggregates, limestone＞diabase＞basalt;Particle size of16mm mineralaggregates, limestone＞diabase＞basalt. Aggregate surface texture on the asphalt/aggregate interface effect on the strength analysis shows that, with the aggregate of fractal dimension increase, interface shearstrength also will increase, basic in a linear relationship. That is to say the rough aggregate surface texture,asphalt/aggregate interface strength is bigger.For the aggregate surface free energy properties, the three different aggregates (limestone, basalt anddiabase) surface free energy have been determined by the rise of capillary method. Diabase has the biggestsurface free energy, followed by limestone and basalt is the minimum one..The asphalt/aggregate interfaceshear test results show that three o aggregates’ surface free energy can’t completely decide theasphalt/aggregate interface strength. The surface energy of the aggregate van der Waals force componentcan component and Lewis acid and base component also cannot be very good to see asphalt/aggregateinterface relevance. Using the surface enery theory to calculation of the asphalt/aggregate the work ofadhesion, diabase the adhesion of the biggest power, then is limestone and basalt. This result is similar tothe same texture of limestone, basalt and disbase aggregates’ asphalt/aggregate interface shear test result,two of them have good correlation. |
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