Aggregates

Abstract

Aggregates are basic materials intensively used in civil engineering works and transport infrastructures construction. These materials could be used on their own nature or in combination with a cementitious material. This chapter describes the main properties of the aggregates, including geometrical, physical, mechanical, chemical and environmental characteristics. The requirements of aggregates to be used in buildings and bridges (structural concrete) and infrastructures of transport are described separately, strongly relying on the technical specifications valid for each application type. The most relevant technical specifications concerning the use of aggregates in buildings and bridges are the standard specification for concrete aggregates. In the case of transport infrastructures, the general characteristics and the most important functions and applicable technical specifications are described for unbound granular layers for road and airport pavements and for use in construction of railway track.