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The use of waste for the construction and rehabilitation of roads, is a strategy to be boosted to stablish regional industrial symbiosis agreements that can support companies to gain competitiveness and reduce the environmental impact associated to their day to day business activity. This article summarizes particular exemples to generate on one hand circular economy models using waste from the pulp and paper industry for soil stabilization, steel slags and foundry sands for asphalt concrete manufacturing, C&DW for the construction of granular sub-bases and on the other to validate the use of renewable materials for pavements construction (bio-polymers like lignin for the production of polymer modified bitumen and bio-rejuvenator agents to enhance asphalt concrete workability and increase the use of reclaimed asphalt pavements or RAP). [ABSTRACT FROM AUTHOR]

This article aims to provide ideas and thoughts for improving, with the means available today in the market and with current machinery, the performance and durability characteristics of paving based on concrete examples in each and every one of the development phases of the works site, from the preparation stage to execution or conservation, etc. This paper seeks to show the current possibilities for building safer and more durable roads. From a futuristic viewpoint perhaps, because no roadworks in the world have so far been undertaken in this way; however, reckoning with all possibilities in existence today and acting in each and every one of the paving process stages, we can ultimately arrive at the ideal works or the Asphalt 4.0 concept in the works development stages described in this text. The goal of this article is to promote substantial improvements in the way road networks are managed, based on concrete ideas from the bitumen mix manufacturing industry that Asefma represents in Spain, to take a giant leap forward in collaborating with the Administrations responsible for the road networks in Spain and thus contribute to better-performing, more durable asphalt paving than what we currently have. The aim of this publication is not to be descriptive in terms of the capabilities provided by the new existing machinery or the characteristics of the new devices and sensors for paving works; rather, it focuses on the possibilities offered by this new machinery in collaboration with current digital technology. Nor does it seek to be specific in the details of the use made of the machinery, which are far better described in Asefma's monographs listed in the bibliography at the end. [ABSTRACT FROM AUTHOR]

The development and study of the rheological and electrical properties of bitumen modified with carbon nanotubes is exposed. This modification transforms the bitumen into electrical semiconductor material, which opens a new range of possibilities of use to a material that, usually, acts as an electrical insulator. As an example of these new applications, design and study of asphalt mixes made with carbon nanotubes modified binders conferring improved self-healing properties to the mixture by microwave absorption are presented. Results showed in this paper have been obtained in the development of the MAMCE project, granted by the Spanish "Ministerio de Economía y Competitividad", call "Innpacto 2011". [ABSTRACT FROM AUTHOR]

Roads in Bogota, Colombia are plagued by both poor pavement conditions and constant precipitation. To tackle these issues, this paper quantitatively measures the effect of stripping and moisture on the bond between AC 60-70 and three aggregates (two sandstone and one limestone, given that they represent those most commonly employed in Bogota's pavements). The idea is to study the aggregate's adhesive and cohesive behavior via the BBS test and the Sessile Drop method. For the asphalt-aggregate bonds, contact angles, wettability and adhesive work under dry and wet conditions were determined. Results identify sandstone aggregate as preferable, especially in terms of moisture damage resistance. Furthermore, this study concludes that the aggregates studied are highly susceptible to water damage, with a Humidity Damage Index less than 0.5. As a result, asphalt mixtures should rely on a modifier to mitigate moisture damage in asphalt mixtures. [ABSTRACT FROM AUTHOR]

La energía superficial libre (ESL) es una propiedad fundamental que puede ser empleada para cuantificar la calidad de interfases o de la adhesión que se genera entre diferentes materiales a través de la aplicación de la teoría termodinámica. Desarrollos recientes han permitido la medición en laboratorio de la ESL de cementos asfálticos (o asfaltos/01 y agregados10', lo cual a su vez ha permitido la evaluación de interfases asfalto-agregado de mezclas asfálticas. El presente artículo tiene como objetivo principal describir estas evaluaciones, sus principales ventajas y aplicaciones, así como algunos resultados específicos de dichas aplicaciones. La ESL de los asfaltos evaluados fue medida empleando el método de Placa Wilhelmy, mientras que la medición correspondiente para agregados se llevó a cabo empleando el USD ("Universal Sorption Device"). Los resultados y el análisis correspondientes sustentan la posibilidad de evaluar interfases asfalto-agregado a partir de mediciones de ESL para proporcionar nueva información que permita mejorar el diseño de mezclas asfálticas y la predicción de su desempeño. The surface free energy (SFE) is a fundamental material property that can be used to quantify the quality of material interfaces or the quality of adhesion between different materials based on thermodynamics principles. Recent developments made it possible to measure the SFE for asphalt cements (or asphalts) and aggregates, which in turns have allowed the assessment of asphalt-aggregate interfaces for asphalt mixtures. The main objective of paper is to describe these evaluations, their advantages and applications as well as some specific results of these applications. The asphalt SFE was measured by using the Wilhelmy Plate method, while the corresponding measurement for aggregates was carried out using the Universal Sorption Device (USD). Corresponding results and analysis support the possibility of assessing asphalt-aggregate interfaces based on SFE measurements to provide new information for improving the design and performance prediction of asphalt mixtures. [ABSTRACT FROM AUTHOR]