Etiqueta: Sustainability

Comparativa medioambiental de muros atendiendo a su ciclo completo de vida

Acaban de publicarnos un artículo en la revista Journal of Cleaner Production (primer decil del JCR), de la editorial ELSEVIER, en la que analizamos una de las construcciones más habituales en la ingeniería civil, como son las estructuras de contención de tierras.

Se ha realizado para ello un análisis de ciclo de vida completo de cuatro tipos de muros: muros de hormigón armado, de hormigón en masa, de gaviones y de escollera. Además se ha realizado un estudio paramétrico para averiguar hasta qué altura de tierras es mejor una u otra tipología. Las conclusiones obtenidas no son evidentes a priori. Podéis verlas en el resumen que os paso a continuación.

Referencia:

PONS, J.J.; PENADÉS-PLÀ, V.; YEPES, V.; MARTÍ, J.V. (2018). Life cycle assessment of earth-retaining walls: An environmental comparison. Journal of Cleaner Production, 192:411-420.  https://doi.org/10.1016/j.jclepro.2018.04.268

Abstract:

Earth-retaining walls are one of the most common structures in civil engineering, a discipline of the construction sector known to produce one of the highest environmental impacts. Therefore, developing cleaner design and construction practices could contribute to a more sustainable future for our planet. To make a step towards this goal, this study comprises the life cycle assessment (LCA) of the four most common earth-retaining walls built between 1 to 6 m of height: cantilever walls, gravity walls, masonry walls and gabion walls to obtain the best solutions for the environment. To assess the environmental impacts caused throughout their whole life-cycle including the production, construction, use and end of life phases, we used the OpenLCA software, the ecoinvent 3.3 database and the ReCiPe (H) method. The associated uncertainties have been considered and the results are provided in both midpoint and endpoint approaches. Our findings show that gabion and masonry walls produce the lowest global impact. On the one hand, gabion walls cause less damage to human health but on the other hand, masonry walls cause less damage to the ecosystems. Furthermore, gravity walls produce similar impacts to gabion and masonry walls between 1 and 3 m of height as well as fewer impacts than cantilever walls for a height of 4 m. In conclusion, gabion and masonry walls are preferable to concrete walls for heights between 1 and 6 m and cantilever walls should be used over gravity walls for greater heights than 4.5 m.

Keywords:

Life cycle assessment; Sustainability; Earth-retaining wall; ReCiPe

Highlights:

  • Four earth-retaining walls are compared to obtain the best environmental solution.
  • The OpenLCA software, the Ecoinvent 3.3 database and the ReCiPe (H) method are used.
  • Gabion walls cause less damage to human health than masonry walls.
  • Masonry walls cause less damage to the ecosystems than gabion walls.
  • Mass concrete walls are cleaner than reinforced ones until 4.5 m of height.

 

 

¿Cómo afectan los costes al mantenimiento de un puente cuando se consideran aspectos sociales?

https://www.ailladearousa.com

Pocas veces se incorporan en los proyectos de puentes actuales las variables sociales como factores determinantes de su diseño. Tampoco se dedica la atención suficiente al análisis del coste del ciclo de vida para evaluar la mejor alternativa posible de diseño. Considerar en nuestros proyectos este tipo de variables podría reducir, por ejemplo, en un 60% los costes de mantenimiento. También se constataría el hecho de que incrementar solamente 5 mm el recubrimiento de las armaduras de las estructuras de hormigón podría reducir el coste del mantenimiento en un 40%. Un ejemplo de la aplicación de este tipo de metodologías es la que nos acaban de publicar en la revista Sustainability. Allí se ha analizado el coste del ciclo de vida de las medidas de prevención aplicado a un puente de hormigón postesado expuesto al ataque de clorhídricos. Para ello se ha elegido el puente de la Isla de Arosa, en Galicia (España). Os dejo el artículo completo y la referencia.

Referencia:

NAVARRO, I.J.; YEPES, V.; MARTÍ, J.V. (2018). Life cycle cost assessment of preventive strategies applied to prestressed concrete bridges exposed to chlorides. Sustainability, 10(3):845. doi:10.3390/su10030845 .

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Análisis de ciclo de vida de puentes óptimos de vigas artesa

Acaban de publicarnos un artículo en la revista internacional Sustainability sobre análisis de ciclo de vida de puentes óptimos de vigas. La evaluación del impacto ambiental se realiza a lo largo del ciclo de vida de puentes de hormigón postesado de vigas artesa que previamente han sido optimizados mediante una metaheurística de algoritmos meméticos. Os dejo a continuación la referencia de la revista. Además os podéis descargar y distribuir el artículo sin problema, pues está editado en abierto:

http://www.mdpi.com/2071-1050/10/3/685/html

Referencia:

PENADÉS-PLÀ, V.; GARCÍA-SEGURA, T.; MARTÍ, J.V.; YEPES, V. (2018). An optimization-LCA of a prestressed concrete precast bridge. Sustainability, 10(3):685. doi:10.3390/su10030685

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Análisis del ciclo de vida: comparación entre dos puentes postesados óptimos de sección en cajón

Acaban de publicarnos un artículo en la revista del JCR (Q2) Sustainability que compara dos puentes postesados óptimos de sección en cajón atendiendo a su ciclo de vida. Creemos que la metodología empleada puede ser de interés para casos de estructuras de hormigón similares a las presentadas. El artículo forma parte del proyecto de investigación BRIDLIFE “Puentes pretensados de alta eficiencia social y medioambiental bajo presupuestos restrictivos“.

Os paso a continuación el resumen y el artículo propiamente dicho, pues está publicado en abierto.

 

 

Abstract:

The goal of sustainability involves a consensus among economic, environmental and social factors. Due to climate change, environmental concerns have increased in society. The construction sector is among the most active high environmental impact sectors. This paper proposes new features to consider a more detailed life-cycle assessment (LCA) of reinforced or pre-stressed concrete structures. Besides, this study carries out a comparison between two optimal post-tensioned concrete box-girder road bridges with different maintenance scenarios. ReCiPe method is used to carry out the life-cycle assessment. The midpoint approach shows a complete environmental profile with 18 impact categories. In practice, all the impact categories make their highest contribution in the manufacturing and use and maintenance stages. Afterwards, these two stages are analyzed to identify the process which makes the greatest contribution. In addition, the contribution of CO2fixation is taken into account, reducing the environmental impact in the use and maintenance and end of life stages. The endpoint approach shows more interpretable results, enabling an easier comparison between different stages and solutions. The results show the importance of considering the whole life-cycle, since a better design reduces the global environmental impact despite a higher environmental impact in the manufacturing stage.

Keywords:

sustainability; environmental impact; life-cycle assessment; construction LCA; bridge LCA; ReCiPe;sustainable construction

Reference:

PENADÉS-PLÀ, V.; MARTÍ, J.V.; GARCÍA-SEGURA, T.;  YEPES, V. (2017). Life-cycle assessment: A comparison between two optimal post-tensioned concrete box-girder road bridges. Sustainability, 9(10):1864. doi:10.3390/su9101864 (link)

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Sustainable assessment of retaining walls through an active learning method considering multiple stakeholders

ABSTRACT: The sustainability approach has changed the modern society. Currently, the sustainability takes into consideration, not only the economic and environmental facets, but also the social facet. Taking into account the three facets of sustainability, this paper shows the application of a method of active learning to assess the sustainability of three real retaining walls. A group of 29 students of the Master of Science in Planning and Management in Civil Engineering at the Universitat Politècnica de València has experienced this assessment. The method followed was proposed by academics of the School of Civil Engineering of the Universitat Politècnica de València (Spain) and Universidad de La Frontera (Chile). An approach multi-criteria and a clusters analysis are part of method, which allows developing a participative process with different points of view about the sustainability. The outcomes show that of this way students can forecast impacts from of the integration of design, planning and the location context of the infrastructure. Result evidence that personal values of each student influences the election of the optimal alternative. The paper also identifies the need to strengthen the conceptualization of social criteria in the students training.

KEYWORDS: Infrastructure, Education, Cluster analysis, Analytic hierarchy process, Civil engineering, Sustainability

REFERENCE:

SIERRA-VARELA, L.; YEPES, V.; PELLICER, E. (2017). Sustainable assessment of retaining walls through an active learning method considering multiple stakeholders. Proceedings of the Ninth International Structural Engineering and Construction Conference, Valencia, Spain, July 24-July 29.  doi: 10.14455/ISEC.res.2017.51

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Special Issue “Sustainable Construction”

High visibility: indexed by the Science Citation Index Expanded, the Social Sciences Citation Index (Web of Science) and other databases. Impact Factor: 1.343 (2015)

Special Issue “Sustainable Construction”

A special issue of Sustainability (ISSN 2071-1050). This special issue belongs to the section “Sustainable Engineering and Science“.

Deadline for manuscript submissions: 30 November 2017

Special Issue Editors

Guest Editor

Prof. Dr. Víctor Yepes
Concrete Science and Technology Institute (ICITECH), Department of Construction Engineering and Civil Engineering Projects, Universitat Politècnica de València Valencia, Spain
Interests: multi-objective optimization; life-cycle assessment; decision-making; sustainability; concrete structures; CO2 emissions; construction management

Guest Editor

Dr. Tatiana García-Segura
Concrete Science and Technology Institute (ICITECH), Department of Construction Engineering and Civil Engineering Projects, Universitat Politècnica de València Valencia, Spain
Interests: multi-objective optimization; durability; safety; sustainability; post-tensioned bridges; maintenance; blended cement; recycled concrete

Special Issue Information

Dear Colleagues,

This “Sustainable Construction” Special Issue comprises selected papers for Sustainability. Construction is one of the main sectors generating greenhouse gases. This industry consumes large amounts of raw materials, such as stone, timber, water, etc. Additionally, infrastructure should provide service over many years without safety problems. Therefore, their correct design, construction, maintenance and dismantling are essential to reduce economic, environmental and societal consequences. That is why promoting sustainable construction is becoming extremely important nowadays. This Special Issue is seeking papers that explore new ways of reducing the environmental impacts caused by the construction sector, as well promoting social progress and economic growth. These objectives include, but are not limited to:

  • The use of sustainable materials in construction
  • The development of technologies and processes intended to improve sustainability in construction
  • The optimization of designs based on sustainable indicators
  • The reduction of the economic, environmental and social impact caused by production processes
  • The promotion of durable materials that reduce the future maintenance
  • The life-cycle assessment
  • Decision-making processes that integrate economic, social, and environmental aspects

Papers selected for this Special Issue are subject to a rigorous peer-review procedure with the aim of rapid and wide dissemination of research results, developments and applications.

Submission

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sustainability is an international peer-reviewed Open Access monthly journal published by MDPI.

Keywords

  • sustainable materials
  • life-cycle assessment
  • sustainable and efficient technologies and processes
  • design optimization
  • durable materials
  • maintenance minimization
  • decision-making

Sostenibilidad del mantenimiento de carreteras bajo presupuestos restrictivos

Foto: laseda.accionistas.es

¿Es posible un mantenimiento sostenible de las carreteras cuando apenas existen presupuestos para ello?

A continuación os dejo el enlace a un artículo científico que nos acaban de publicar donde se muestra la posibilidad de utilizar técnicas de optimización heurística para conseguirlo.

 

 

 

 

 

Puedes solicitar una copia gratuita de este artículo en la siguiente dirección: https://www.researchgate.net/publication/312598336_Towards_a_sustainable_optimization_of_pavement_maintenance_programs_under_budgetary_restrictions

 

Referencia: 

TORRES-MACHI, C.; PELLICER, E.; YEPES, V.; CHAMORRO, A. (2017). Towards a sustainable optimization of pavement maintenance programs under budgetary restrictions. Journal of Cleaner Production, 148:90-102. http://www.sciencedirect.com/science/article/pii/S0959652617301142

Abstract:

Transport sector constitutes the second largest source of global greenhouse gas (GHG) emissions, being the road transportation the main contributor of these emissions. Efforts in the road sector have traditionally focused on vehicle emissions and infrastructure is typically not included in the emissions account. Road environmental impact is estimated to increase by 10% if the stages of road design, construction, and operation were considered. Previous literature has widely study sustainable practices in pavement design and construction, with little attention paid to maintenance. Current state of practice reveals that pavement managers barely consider environmental performance and their evaluations solely rely on technical and economic criteria. This situation creates the need to incorporate, in an integrated manner, technical, economic, and environmental aspects in the design of maintenance programs. The main objective of this research is to develop a tool for the optimal design of sustainable maintenance programs. Given a maintenance budget, the tool aims to maximize the long-term effectiveness of the network while minimizing GHG emissions derived from the application of maintenance treatments. The capability of the proposed tool is analyzed in a case study dealing with an urban pavement network. In comparison to the traditional maintenance policy, the proposed tool designs maintenance programs that increase the average network condition by up to 22% and reduces GHG emissions by 12%. This application also analyzes the effect of different budgetary scenarios in the technical and environmental performance of the network. This application helps pavement managers in the trade-off between budget and network performance.

Keywords:

  • Greenhouse gas emissions;
  • Long-term effectiveness;
  • Optimization;
  • Sustainability;
  • Pavement management;
  • Sensitivity analysis

Aplicación de los métodos de decisión multicriterio al diseño sostenible de puentes

Puente en cajón postesado sobre el Turia (Quart de Poblet). Proyectado por Javier Manterola y construído por Dragados y Construcciones en 1991.

Actualmente existe una tendencia clara hacia la sostenibilidad en los proyectos de estructuras, para lo cual es necesario equilibrar los criterios que apoyan esta sostenibilidad: la economía, el medio ambiente y la sociedad. Estos pilares básicos presentan objetivos diferentes y habitualmente enfrentados entre sí. Esta realidad conduce hacia la necesidad de adoptar procesos de toma de decisiones que permitan alumbrar soluciones capaces de satisfacer, de la mejor manera posible, los principios de sostenibilidad citados. Los puentes forman parte de las infraestructuras básicas de comunicación entre los distintos territorios. Por lo tanto, constituye una necesidad ineludible garantizar la sostenibilidad de este tipo de estructuras a lo largo de su ciclo de vida.

A continuación se presenta un artículo recién publicado que tiene como objetivo principal revisar la aplicación de las técnicas de decisión multicriterio al caso de los puentes. Esta investigación se enmarca dentro del proyecto BRIDLIFE (BIA2014-56574-R), en el cual participan los autores. La revisión se ha realizado atendiendo a las fases del ciclo de vida del puente, teniendo en cuenta aquellos trabajos que proponen soluciones y realizan un proceso directo de toma de decisiones respecto a estas soluciones. Asimismo, también se han considerado aquellas aportaciones que, a pesar de no realizar una selección entre varias soluciones, aplican un método de toma de decisiones para evaluar una solución en particular. La relevancia de estos trabajos estriba en la forma en que se realizan los procesos de evaluación, los cuales constituyen la piedra angular para el proyecto de un puente desde el punto de vista de la sostenibilidad, atendiendo a todas y cada una de las fases de su ciclo de vida.

Este artículo lo podéis descargar en el siguiente enlace: http://www.mdpi.com/2071-1050/8/12/1295, aunque también os lo dejo en el post para vuestra descarga directa.

Referencia:

Penadés-Plà, V.; García-Segura, T.; Martí, J.V.; Yepes, V. A Review of Multi-Criteria Decision-Making Methods Applied to the Sustainable Bridge Design. Sustainability 2016, 8, 1295.

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Evaluación del ciclo de vida de muros óptimos de contrafuertes

s09596526Nos acaban de publicar un artículo que versa sobre la evaluación del ciclo de vida de muros óptimos de contrafuertes. En este estudio se han analizado 30 muros optimizados de varias alturas (4-13 m), con terrenos de distintas capacidades portantes (0,2; 0,3 y 0,4 MPa). Os paso la referencia, el resumen y el enlace al artículo. Espero que os sea de interés.

NOTICIA: Hasta el 21 de diciembre de 2016 podéis descargaros gratis el artículo directamente en:

http://authors.elsevier.com/a/1Tz-03QCo9JQWX

Aprovecha la oportunidad para no pagar los costes de descarga.

Highlights

  • A life cycle assessment over 30 optimized earth-retaining walls is conducted
  • Concrete presents the highest contribution to all impact categories
  • Steel significance on every impact increases with wall size
  • The recycling rate influences each impact category to different degrees
  • Savings on abiotic resource depletion with 70% recycled steel are about 72%

 

l-31-fig31-3-counterfort-retaining-wallsAbstract:

In this paper life cycle assessments are carried out on 30 optimized earth-retaining walls of various heights (4–13 m) and involving different permissible soil stresses (0.2, 0.3 and 0.4 MPa) in Spain. Firstly, the environmental impacts considered in the assessment method developed by the Leiden University (CML 2001) are analyzed for each case, demonstrating the influence of the wall height and permissible soil stress. Secondly, this paper evaluates the contribution range of each element to each impact. The elements considered are: concrete, landfill, machinery, formwork, steel, and transport. Moreover, the influence of the wall height on the contribution of each element over the total impact is studied. This paper then provides the impact factors per unit of concrete, steel, and formwork. These values enable designers to quickly evaluate impacts from available measurements. Finally, the influence of steel recycling on the environmental impacts is highlighted. Findings indicate that concrete is the biggest contributor to all impact categories, especially the global warming potential. However, the steel doubles its contribution when the wall heights increase from 4 m to 13 m. Results show that recycling rates affect impacts differently.

Keywords

Life cycle assessment; Retaining wall; Sustainability; Buttressed wall

Referencia:

ZASTROW, P.; MOLINA-MORENO, F.; GARCÍA-SEGURA, T.; MARTÍ, J.; YEPES, V. (2017). Life cycle assessment of cost-optimized buttress earth-retaining walls: a parametric study. Journal of Cleaner Production, 140:1037-1048. DOI: 10.1016/j.jclepro.2016.10.085

 

 

Appraisal of infrastructure sustainability by graduate students using an active-learning method

file.FeedFileLoaderAppraisal of infrastructure sustainability by graduate students using an active-learning method

Abstract:

Currently many university programs in the construction field do not take sustainability into account from a holistic viewpoint. This may cause a lack of sensitivity from future professionals concerning sustainability. Academics in construction must endeavor to instill a culture of sustainability in the curricula of their students. Therefore, this study proposes an active-learning method that allows graduate students in the construction field to take into consideration infrastructure sustainability from a variety of perspectives in a participatory process. The students applied an analytical hierarchical process to determine the appraisal degree of each criterion. A cluster statistical analysis was carried out, aiming to identify the profiles that influence decision-making. This method was applied to two classes of graduate students enrolled in the Master of Planning and Management in Civil Engineering at the Universitat Politècnica de València. This method identified a correlation between the profiles toward sustainability and the characteristics of the chosen infrastructure. It was also found that the method fulfills educational purposes: most of the students obtained more than 65% of the target learning outcomes. This approach promotes awareness and sensitivity to different points of view of the sustainability in a participatory context. It can be replicated in other contexts so as to obtain appraisals regarding various criteria that help enhance decision-making.

Highlights

  • Proposal of a method that allows students to consider infrastructure sustainability.
  • Participatory learning method that promotes integral sustainability.
  • Students profiles’ identification influencing decision making toward sustainability.
  • The profiles of evaluators influence the prioritization among alternatives.

Reference:

PELLICER, E.; SIERRA, L.A.; YEPES, V. (2016). Appraisal of infrastructure sustainability by graduate students using an active-learning method. Journal of Cleaner Production, 113:884-896. DOI:10.1016/j.jclepro.2015.11.010

Os dejo a continuación la versión autor del artículo:

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