Influence of traffic delay produced during maintenance activities on the life cycle assessment of a road

This paper analyses the relevance of the traffic delay generated during the A-8 Spanish Motorway maintenance activities in order to make recommendations for inclusion within the LCA of roads. Six congestion scenarios combining the level of service of the Motorway and the alternative N-634 route have been evaluated using two software packages: KyUCP (macro-simulation) and Aimsun (micro-simulation), whose results have been transferred into emissions using MOVES. After performing the LCA considering a functional unit of a 1-km lane with an analysis period of 30 years, results show the huge importance of this stage in all the scenarios analysed

Environmental impact assessment of induction-healed asphalt mixtures

This paper demonstrates the sustainability of induction-healed asphalt mixtures (HEALROAD) by comparing the impacts this technology causes with those generated by asphalt mixtures maintained byconventional practices such as mill and overlay. The functional unit selected is a 1 km lane with ananalysis period of 30 years, and the stages considered are production, construction, maintenance,congestion, leaching and end-of-life. Two case studies have been analysed to evaluate the influence ofdifferent traffic strategies on the environmental impact of each maintenance alternative. Results showthe benefits of using the induction technology at hot points where traffic jams occur.This work was supported by the ERA-NET Plus Infravation 2014 Call under grant agreement no. 31109806.0003 - HEALROAD. Funding partners of the Infravation 2014 Call are: Ministerie van Infrastructuur en Milieu, Rijkswaterstaat, The Netherlands, Bundesministerium für Verkehr, Bau und Stadtentwicklung, Germany, Danish Road Directorate, Denmark, Statens Vegvesen Vegdirektoratet, Norway, Trafickverket-TRV, Sweden, Vegagerdin, Iceland, Ministere de l’Ecologie du Developpement Durable et de l’ Energie, France, Centro para el Desarrollo Tecnológico Industrial, Spain, Anas S.P.S, Italy, Netivei Israel - National Transport Infrastructure Company LTD, Israel and Federal Highway Administration USDOT, USA. The HEALROAD project has been carried out by the University of Cantabria, University of Nottingham, German Federal Highways Research Institute (BASt), European Union Road Federation (ERF), Heijmans Integrale projecten B.V. and SGS INTRON B.V

Multi-Criteria Selection of Additives in Porous Asphalt Mixtures Using Mechanical, Hydraulic, Economic, and Environmental Indicators

Porous asphalt (PA) mixtures are more environmentally friendly but have lower durability than dense-graded mixtures. Additives can be incorporated into PA mixtures to enhance their mechanical strength; however, they may compromise the hydraulic characteristics, increase the total cost of pavement, and negatively affect the environment. In this paper, PA mixtures were produced with 5 different types of additives including 4 fibers and 1 filler. Their performances were compared with the reference mixtures containing virgin bitumen and polymer-modified bitumen. The performance of all mixes was assessed using: mechanical, hydraulic, economic, and environmental indicators. Then, the Delphi method was applied to compute the relative weights for the parameters in multi-criteria decision-making methods. Evaluation based on distance from average solution (EDAS), technique for order of the preference by similarity to ideal solution (TOPSIS), and weighted aggregated sum product assessment (WASPAS) were employed to rank the additives. According to the results obtained, aramid pulp displayed comparable and, for some parameters such as abrasion resistance, even better performance than polymer-modified bitumen, whereas cellulose fiber demonstrated the best performance regarding sustainability, due to economic and environmental benefits.This work and the APC are funded by SAFERUP! Project, from the European Union’s Horizon 2020 research and innovation program under, the Marie Skłodowska-Curie grant agreement No. 765057

Artificial reefs built by 3D printing: systematisation in the design, material selection and fabrication

The recovery of degraded marine coasts and the improvement of natural habitats are current issues of vital importance for the development of life, both marine and terrestrial. In this sense, the immersion of artificial reefs (ARs) in the marine environment is a way to stimulate the recovery of these damaged ecosystems. But it is necessary to have a multidisciplinary approach that analyses the materials, designs and construction process of artificial reefs in order to understand their true impact on the environment. For this reason, this paper presents the manufacture of artificial reefs by 3D printing, proposing designs with a combination of prismatic and random shapes, with different external overhangs as well as inner holes. For the definition of the artificial reef designs, criteria provided by marine biologists and the results obtained from a numerical simulation with ANSYS were taken into account, with which the stability of the artificial reefs on the seabed was analysed. Three dosages of cement mortars and three dosages of geopolymer mortars were studied as impression materials. The studies included determination of the rheological properties of the mortars, to define the printability, determination of the cost of the materials used, and determination of the mechanical strength and biological receptivity in prismatic specimens that were immersed in the sea for 3 months. To evaluate the environmental impact of the materials used in the production of the mortars, a Life Cycle Assessment (LCA) was carried out. In order to choose the mortars that encompassed the best properties studied, Multi-Criteria Decision Making (MCDM) was applied and the two best mortars were used for the manufacture of the artificial reefs. Finally, the advantages and disadvantages of the 3D printing process used were analysed. The results of the studies carried out in this research show that cement mortars have better characteristics for artificial reef applications using 3D printing, and that the technique applied for the manufacture of the artificial reefs allowed the digital models to be faithfully reproduced.This work has been co-financed by the European Regional Development Fund through the Interreg Atlantic Area Programme, under the project “Artificial Reef 3D Printing for Atlantic Area - 3DPARE” (EAPA_174/2016). Besides, the authors want to thank the following companies for their contribution: Solvay, for supplying the fly ash and sodium hydroxide; BASF, for providing the additives used in the research; Abonomar S.L., for providing the seashells sand; FCC ámbito, for providing the crushed recycled glass and Grupo Cementos Portland Valderribas (Mataporquera plant) for providing the cement

Alternativas para optimizar el aprovechamiento de los residuos sólidos urbanos en la Mancomunidad de Montejurra (Navarra)

Máster en Ingeniería de Caminos, Canales y Puerto

Recommendations for the application of the life cycle assessment methodology to sphalt pavements

RESUMEN: La infraestructura vial tiene una gran importancia en la vida cotidiana de millones de ciudadanos, pero se generan grandes repercusiones económicas, ambientales y sociales al intentar mantenerla en un estado adecuado. La metodología del análisis de ciclo de vida (ACV) permite cuantificar el impacto ambiental potencial de productos y procesos. Sin embargo, su aplicación a carreteras todavía se encuentra en una etapa inmadura debido a la existencia de lagunas en el conocimiento y a la falta de directrices y metodologías que faciliten su inclusión. Por ello, la presente tesis doctoral trata de analizar en mayor profundidad diversos aspectos de la metodología de ACV que están generando incertidumbre en su aplicación a firmes asfálticos, de forma que se impulse la realización de ACVs más eficaces, fiables y completos. La investigación partió con la creación de una extensa base de datos relativa a todos los procesos que intervienen a lo largo de la vida de la carretera. Después, se ahondó en la sustitución de áridos naturales de alta calidad por escorias de arco eléctrico. A continuación, se abordó el efecto de la predicción de la vida de un firme asfáltico en los resultados del ACV. Finalmente, se evaluó la relevancia de los retrasos sufridos por los usuarios durante las operaciones de mantenimiento.ABSTRACT: Road infrastructure has great importance in the daily lives of millions of citizens. However, maintaining reliable performance of roads generates great economic, environmental and social impacts. Life cycle assessment (LCA) methodology has been applied in numerous case studies to calculate the potential environmental impact produced by a product or process. However, applying LCA to pavements is still at an immature stage due to the existence of gaps in the knowledge and lack of guidelines and methodologies which ease their inclusion. For this reason, this doctoral thesis attempts to analyze more deeply several aspects of the LCA methodology that are generating uncertainty in its application to asphalt pavements, so as to promote more efficient, reliable and complete LCAs. The research started with the creation of an extensive database concerning all the processes involved in the road life cycle. Then, the replacement of high-quality natural aggregates by electric arc furnace slags was studied in depth. Later, the effect of predicting the lifespan of an asphalt pavement on LCA results was addressed. Finally, the relevance of the traffic delay produced during the maintenance of a highway on its total LCA was evaluated

Analysis of replacing virgin bitumen by plastic waste in asphalt concrete mixtures

ABSTRACT: Polymers are used worldwide for their unique properties such as a light weight or chemical resistance, but which have led to an environmental challenge because of the time they need to completely decompose when buried in landfills. Complementarily, bitumen generates the second biggest environmental impact in the construction of a road. This paper analyses the mechanical, environmental and economic performance of replacing 25% of bitumen with two low-cost plastic wastes (cable plastic and the film fraction from household packaging waste) in an asphalt mixture. The results demonstrated the feasibility of the technology from the 3 viewpoints analysed. The plastic-modified mixtures achieve reductions of more than 17% and 11% in the economic and environmental impact when the analysis is focused on the wearing course

Mechanical, environmental and economic feasibility of highly sustainable porous asphalt mixtures

Road infrastructure plays a crucial role in the social and economic development of nations but also generates several environmental problems. To deal with these, three technologies were combined to produce highly sustainable porous asphalt mixtures: namely replacement of natural aggregates, reduction in manufacturing temperature and use of a nano-modified binder. The feasibility of the mixtures was evaluated by applying mechanical tests and performing a life-cycle assessment (LCA) and life-cycle cost analysis (LCCA). The results demonstrated the good behaviour of these sustainable mixes, enabling more than 12% and 15% reduction in the environmental and economic impacts of the road.This work was supported by the European Union’s Seventh Framework Programme for research, 419 technological development and demonstration [Grant Agreement n° 605404], the FPU Programme of the 420 Spanish Ministry of Education, Culture and Sport [grant number FPU-1/06997] and the doctoral studentship 421 programme of the University of Cantabria, co-financed by the Government of Cantabria

Life cycle assessment (LCA) and multi-criteria decision-making (MCDM) analysis to determine the performance of 3D printed cement mortars and geopolymers

A comparison between low-clinker cement and geopolymer mortars for their application in 3 D printing is discussed in this paper. The mortars are composed of materials with low environmental impact, such as cements with low clinker content, by-products of the industry and recycled aggregates. The developed mortars were both mechanically and rheologically characterized. The environmental impact was studied by LCA. To select the most suitable dosages, MCDM analysis was applied based on cost of materials, printability and LCA. Compressive strength was considered as a normalizing parameter for both the LCA and cost. The mortars showed good printability and suitable mechanical strength, being higher in the cement mortars. The LCA showed that the geopolymer mortars have a higher environmental impact due to the use of sodium hydroxide. Likewise, MCDM revealed that low-clinker cement mortars are at the top of the ranking, due to a lower environmental impact and lower cost of materials.This work has been co-financed by the European Regional Development Fund through the Interreg Atlantic Area Programme, under the project 3DPARE (EAPA_174/2016). This work reflects the authors’ opinion, so the authorities of the programme are not responsible for the use of the information here included