Origin, Usage and Production of Unbound Granular Materials for Road Construction

This paper draws mainly on Chapter 3 of the final report of the European Commission COST 337 action where an overview was given, based on the work of Task Group 2c, on the granular materials that are used in unbound layers of road construction in Europe. The overview is based on information collected from all participating countries. Chapter 3 of the final report also reviews, based on the work of Task Group 2d, production, construction and quality control practices for road work in Europe but this paper gives an overview on the production practices. There are continuing requirements for more efficient use of road building materials, which are no longer as readily available as earlier. Environmental constraints are increasingly preventing the use of naturally occurring materials, which means that granular materials must be used with greater efficiency. Secondary materials, not previously used, should be increasingly used in road pavements. For the covering abstract see ITRD E118503.