EVALUATING THE RELATIONSHIP BETWEEN DYNAMIC SHEAR MODULUS AND NANO SCALE MODULUS OF ASPHALT BINDERS AT DIFFERENT AGING CONDITIONS

Abstract

Traditionally, asphalt binder is characterized by a dynamic shear rheometer, which applies a shear
load on a bulk volume of liquid asphalt binder to determine shear modulus (G*). Recently, a nanoindentation test
can characterize an asphalt binder film in the form of a coating around roadway aggregates, which is more practical.
In a nanoindentation test, a sharp tip is used to indent an asphalt film while residing on an aggregate surface to
determine nanoindentation modulus (E). This study evaluates whether there is a relation between G* and E. For
both tests, replicate samples were conditioned in three ways: unaged, rolling thin film oven aged, and pressure
vessel aging. Results show that the E-value is approximately 2 to 6 times larger than the G*-value based on all
samples/conditioning.