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The recycled rate of Construction & Demolition Waste (C&DW) in Spain is below the minimum required by the European Union. The reasons are: administrative, technical, economical, cultural, among other. To increase recycled rates and fulfil the EU requirements, it is necessary to devise a strategy to tackle on these conditions. Andalusia Regional Government has launched its Plan to encourage the use of C&DW in roads. This Plan is based on four pillars: Research, both in the processing of recycled aggregates from C&DW and in the design of road pavements. Validation of the technologies in pilot demonstrators. Analysis of results and comparison with natural aggregates. Drafting of Technical Prescriptions & Standards to encourage the use of C&DW in road pavements. Assessment of the quality certified by recycled aggregates providers. [ABSTRACT FROM AUTHOR]

The use of industrial sub-products in the construction of roadways is an increasingly widespread practice in this country. Specifically, ashes from thermal plants as infill material in roadways have been used for several decades in Spain, with satisfactory results. These are unconventional materials, classified as marginal soils according to the PG-3, that while not completely complying with the regulatory specifications in force, can be satisfactorily employed so long as due precautions are adopted. This is the case with the slip road giving access to the Hospital Universitario Central of Asturias from the A66 and A66a dual carriageways, where a good part of the infill executed is comprised of ashes from the thermal plants of La Pereda (Mieres) and Soto de Ribera (Ribera de Abajo). The greater part of the material has been taken from the latter. This article will describe the physical, chemical, mineralogical and mechanical characteristics of these materials, associated with their source, their geotechnical performance and their laying, together with the precautions adopted in the execution of the infill. [ABSTRACT FROM AUTHOR]

This article describes the situation of the use of black slag (first fusion) from electric furnace steelmaking on the roads of the Basque Country. The Basque Country has high levels of steel production and consequently generates large volumes of slag. This slag, when properly treated, is turned into iron and steel aggregate that competes in quality with the best natural aggregates. It is a hard aggregate, unsusceptible to water, with good shape and resistant to polishing. Its principal drawback is its high specific weight, which raises the price of transport. The Basque Country had drafted a set of regulations that was included in the Pavement Design Regulation published in 2007. This Regulation imposed stringent limitations on the use of iron and steel aggregate in bottom layers of pavement because of the possibility of expansion, which is difficult to predict owing to the presence of free magnesia and difficult to measure in the lab. Some trial sections were later launched that confirmed that many of the restrictions could be removed given that, with the trials currently available and the limitations imposed on materials, no expansions occur. As a consequence, the new version of the Pavement Regulation of 2012 features a set of revised specifications for the use of iron and steel aggregate in gravels and bitumen mixtures. [ABSTRACT FROM AUTHOR]