The Swedish government has laid down 15 environmental goals to transform Sweden into an ecological society. One goal calls for the reduced extraction of natural gravel and greater use of recycled material. It has been estimated that 1-1.5 million tonnes of concrete are available annually in Sweden for crushing and recycling. Laboratory and field tests showed that the stiffness and stability characteristics of crushed concrete are good. Stiffness increases with time due to a carbonation process. Investigations show that the frost resistance of crushed concrete is reduced if the material is saturated with water. Following participation in field and laboratory investigations, VTI compiled a handbook on the use of crushed concrete in roads in which the concrete is based into four classes according to quality and purity. According to Swedish experience, crushed concrete should be used first as sub-base and secondly as road-base.
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