Asphalt Mixture Mixing Rheological Properties Research

Asphalt pavement is made by the aggregates and asphalt mixing and rolling as formed. It has rheological properties, in mixing, compaction and service stages. Aggregates volume is about 85 percent of the total volume of asphalt mixture. Aggregate geometric features have a great influence on the rheological properties of different stages of asphalt mixture. At present, the research of aggregate geometrical features are not systematic and comprehensive, at the same time, we only study the asphalt mixture of rheological properties of service stage.In this paper, the author analyses single aggregate size, shape, angularity using digital image evaluation system, and the then gives geometric features of the single grain aggregate and particle swarm based on statistics. According to the properties of mixing stages, we develop asphalt mixture mixing rheological properties tester, analysis the influence of rheological properties parameters such as mixing time, temperature on mixing torque, puts forward the asphalt mixture mixing rheological properties test methods. Based on these, we analysis the influence of the aggregate geometry features on asphalt mixture mixing rheological properties.Research results show that:The same lithology, different aggregate size groups have similar shape index and angularity. Aggregate screening diameter and aggregate mixing rheological properties--k value have a good linear relationship. The different lithology, same aggregate size groups, their shape index and angularity have certain sorting, shape index: limestone 2>basalt>limestone 1>gneiss, angularity:limestone 1>basalt>limestone 2>gneiss. Aggregate shape index and asphalt mixture mixing rheological properties have a good linear relationship.