01624309

Component

Asphalt mixture is a typical composite material containing mineral aggregates and asphalt mastics. The interaction between aggregates and asphalt mastics certainly influences the mechanical nature of mastics, which has not attracted sufficient attentions. In this study, the effects of aggregates mineralogy on rheology of asphalt mastics were investigated by the developed binder rheological tests. Limestone and basalt disks with similar roughness were attached on original steel plates, and strain sweep and frequency sweep tests in contact with steel, limestone and basalt disks were conducted at different temperatures utilizing Dynamical Shear Rheometer (DSR). Several key parameters were employed herein to characterize the rheological behavior of mastics in linear viscoelastic (LVE) and nonlinear viscoelastic (NLVE) regions. The strain sweep results show that aggregate surfaces cause stiffness increase and ductility reduction of mastics. The filler-asphalt ratios and temperatures influence the impacts of aggregate surfaces on rheology of mastics. Limestone surface generally stiffens the mastics more significantly relative to basalt. However, moduli of mastics with 1.1 filler-asphalt ratio at 25°C hint the inferiority of limestone and superiority of basalt. The frequency sweep results indicate that the reinforcement of aggregates declines with increasing frequency and strengthens with rising temperature. The stiffening of limestone surface is overtaken for the mastics with high filler-asphalt ratio at high temperature. Therefore, aggregate surfaces should be introduced to mastics foundational researches, and the rheological difference induced by aggregate surfaces may be considered to optimize the filler-asphalt ratio or select appropriate aggregates.

This paper was sponsored by TRB committee AFK30 Standing Committee on Non-Binder Components of Asphalt Mixtures. Alternate title: Effects of Aggregates Mineralogy on Rheology of Asphalt Mastics.

01618707

17-02881

English

15p

2017

Transportation Research Board 96th Annual Meeting

Digital/other

Figures; References; Tables

Aggregates; Asphalt mixtures; Basalt coarse aggregates; Limestone aggregates; Mastic asphalt; Mineralogy; Rheology

Dynamic shear rheometry

Highways; Materials; Pavements

Transportation Research Board Annual Meeting 2017 Paper #17-02881

TRIS, TRB, ATRI

Dec 8 2016 11:05AM