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Description:
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Stone matrix asphalt (SMA ) mixtures rely on stone -on -stone contacts among
particles to resist applied forces and permanent deformation . Aggregates in SMA should
resist degradation (fracture and abrasion ) under high stresses at the contact points . This
study utilizes conventional techniques as well as advanced imaging techniques to
evaluate aggregate characteristics and their resistance to degradation . Aggregates from
different sources and types with various shape characteristics were used in this study .
The Micro -Deval test was used to measure aggregate resistance to abrasion . The
aggregate imaging system (AIMS ) was then used to examine the changes in aggregate
characteristics caused by abrasion forces in the Micro -Deval .
The resistance of aggregates to degradation in SMA was evaluated through the
analysis of aggregate gradation before and after compaction using conventional
mechanical sieve analysis and nondestructive X -ray computed tomography (CT ) . The
findings of this study led to the development of an approach for the evaluation of
aggregate resistance to degradation in SMA . This approach measures aggregate
degradation in terms of abrasion , breakage , and loss of texture . |