Characteristics of aggregates used in road construction in Portugal, complying with the requirements of European Conformity (CE marking)

In the context of European Conformity (CE marking), an inventory on the aggregates used in road construction in Portugal, encompassing 145 producers (68%) and 228 production centres (79%) was carried out, aiming to support the normalisation of activity for aggregates. A broad and representative characterisation of the geometric, physical, mechanical, chemical, and weathering properties of the aggregates was obtained. A total of 106 aggregate sizes allowed the delineation of two predominant dimensional combinations. Aggregates showed dependence on the lithological type, especially with respect to geometrical, physical, and mechanical properties. More than 30% of the all-in aggregates did not satisfy the sand equivalent category SE50 and the methylene-blue category MB2.5, requiring great care in the establishment of specifications. For high levels of performance, in terms of mechanical resistance, the percentage of aggregates satisfying the Los Angeles category LA30 and the polished stone value category PSV50 was quite low. Comparisons with other countries were not possible as no similar data compilation or inventory was found. The present research aims at improving the application of European aggregate standards and, hopefully, at triggering similar work in other countries, especially European ones, in order to contribute to new international standards or to the revision of those standards currently in force.