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Resource preservation and increased waste recycling are important for sustainability in Europe. Thus, it is essential to achieve environmentally safe and sound management of quarry waste (QW) at European and national level. Rock materials recycling practice has therefore been studied in Norway and Italy. At present, recycling levels vary and systematic recovery is not common in European countries. Furthermore, QW is often landfilled owing to unclear legislation and a general lack of technical data. It was found that 80 - 90% and 30 - 80% of the quarrying volumes end up as QW in Norway and Italy, respectively. Furthermore, the fine fraction constitutes around 40% of the total production of dimension stone and natural aggregate in Norway. However, continuing project initiatives over the past 5 - 10 years have shown that QW can be used to produce aggregate. In addition, positive economic and environmental effects are likely to be achieved by systematic recycling of QWplanned by industries and public authorities. However, no significant incentives for recycling or systematic approaches for local aggregate exploitation exist in Italy and Norway. These need to be developed and implemented to change current practice in a major way. [ABSTRACT FROM AUTHOR]

Geological factors (mineralogy, structure, degree of weathering), processing method (crushing, sieving, washing, storing) and user technology for a specific area of use (e.g. asphalt pavements) should be the selecting criteria for crushed rocks used in the construction industry. While the last two criteria have been widely studied, the geological origin of the material has been less considered. Mechanical properties, shape, gradation of the stone material and affinity with the binder are considered the main discriminating factors in road construction. Although those properties are extremely relevant to avoid or milden difficult challenges for pavement surface layers, a deeper knowledge of the geological properties of materials exploited could lead to a general improvement of the overall resistance and durability of the road surface, especially in extreme weathering conditions. The purpose of this work is to investigate the influence of the rock materials properties (mineralogy, texture and porosity expressed by water absorption coefficient) in asphalt pavements. Different samples of aggregates and asphalt mixtures used in Norwegian and Spanish roads were tested with the Cantabro test after conditioning in sodium chloride and freeze–thaw cycles. Mineralogy, grain size, grains bonding, orientation and porosity (expressed by water absorption coefficient) could be related to the mechanical resistance of the aggregates and asphalt mixture behaviour. Even if just a qualitative analysis, the petrographic analysis of the rocks appeared to be a relevant tool to estimate the quality and the long-term durability of aggregates and asphalt mixtures already during the design phase. [ABSTRACT FROM AUTHOR]