Differential thermal expansion and contraction: a mechanistic approach to adhesion in asphalt concrete

摘要

This paper introduces a simple mechanistic approach that describes the response of the asphalt-aggregate system to temperature changes. The concept recognizes the thermal incompatibility between asphalt cement and aggregate. Owing to the considerable difference in the coefficients of thermal expansion of aggregate and asphalt, the asphalt matrix will attempt to contract more than the aggregate during thermal cooling. An analytical model was derived to estimate the thermally induced stresses resulting from differential thermal contraction. The experimental investigation which is part of a study investigating adhesion, verified the findings of the analytical approach. Findings from this study explained field and laboratory observations made earlier by other investigators. These observations were associated with asphalt concrete low-temperature performance and its resistance to stripping.