Fundamental Properties of Asphalts and Modified Asphalts, III

SUBTASK 2-4. LOW-TEMPERATURE PROPERTIES
Statement of Problem
The contributions of asphalt source (or chemical composition) and environmental conditions to
pavement low-temperature performance are not completely understood. Although the current
purchase specifications seem to prevent early failure, there is little confidence in any prediction
of long-term behavior.
Approach
Use differential scanning calorimetry and stress relaxation rheometry to determine asphalt
component influences on low-temperature properties. This effort will validate the use of lowtemperature
stress relaxation tests for determining asphalt mechanical properties.
Use a similar approach to determine the influence of oxidative aging on low-temperature
properties.
Goal
The goal of this work is to provide the low-temperature information to support the development
of an advanced fundamental understanding of how chemical types, reactions, and structures
determine the physical properties of asphalts and the long-term performance of asphalt
pavements.
Support of FHWA Strategic Goals
The work conducted in this subtask to better understand low-temperature asphalt behavior
supports the FHWA strategic goal that addresses optimizing pavement performance through the
development of longer lasting asphalt pavements, thus decreasing the demand for reconstruction
of pavements.
Work Conducted This Quarter
According to the Contract DTFH61-07-D-00005 documents, Year-2 work on this topic must be
shifted to Subtask 3-7. No Task 3 research has been authorized.
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