Shaping the Right Mix

Many countries are introducing new specifications concerning the shape and surface texture of asphalt aggregates. Imposing tighter controls on aggregate shape should improve field performance and reduce maintenance costs. This article describes how the aggregate industry is developing new crushing and screening practices to provide the required aggregates. Cubical particles with sharply defined edges are said to perform best in asphalt. For medium to heavy traffic applications, particles should be cubical, yet angular, to ensure good stability and rigidity. Using cubical aggregate in asphalt also reduces the optimum bitumen content of the mixtures. Aggregates with a rough surface texture provide high stability mixes for situations where rutting resistance is important. A recent study on different types of crushing determined that rock-on-rock vertical shaft impactors produced the best aggregate for asphalt.

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  • English

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Filing Info

  • Accession Number: 01001892
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 12 2005 10:53AM