Valorização de resíduos plásticos na modificação de betumes para pavimentos rodoviários

Com o aumento do tráfego rodoviário são colocadas maiores exigências aos pavimentos, surgindo a necessidade de melhorar o seu desempenho. Um método que pode melhorar significativamente a qualidade dos pavimentos flexíveis é a adição de polímeros aos ligantes/misturas betuminosas. Assim, foram produzidos ligantes modificados com polímeros reciclados, em diferentes condições, cujo desempenho foi comparado com o de ligantes convencionais e de um ligante modificado comercial. Os resultados dos ensaios laboratoriais serão utilizados na seleção de resíduos plásticos e das condições de produção do betume modificado para otimizar o seu comportamento, salientando-se que este estudo procura promover a reutilização de resíduos de uma forma mais ecológica e económica.Financiado por Fundos FEDER através do Programa Operacional Fatores de Competitividade – COMPETE e por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projeto PLASTIROADS (PTDC/ECM/119179/2010) e do projeto estratégico UI 4047 – 2011-2012

A new life for cross-linked plastic waste as aggregates and binder modifier for asphalt mixtures

Every year, millions of tons of plastic waste, with potential to be reused, are wasted in landfills. Based on a literature review and in a local market analysis, cross-linked polyethylene (PEX) waste arose as the material with the greatest potential to be tested for incorporation in asphalt mixtures due to the difficulty in its recycling and the lack of solutions for its reuse. Thus, in the present work, mixtures produced with and without PEX were tested in order to compare their performance, aiming at understanding if this waste could successfully be used as an alternative material for this type of application. Thus, water sensitivity, rutting resistance, stiffness modulus and fatigue cracking resistance tests were carried out on asphalt mixtures with up to 5% PEX. Based on the results obtained, it can be concluded that the incorporation of PEX in asphalt mixtures is a viable solution for paving works, especially when high service temperatures are expected. It also decreases the density of the mixture, which can be attractive to lighten structures. Thus, this technology contributes to give new life to cross-linked polyethylene plastic waste.The authors gratefully acknowledge the funding provided by the Portuguese Government (Portuguese Foundation for Science and Technology) and by the Competitiveness Factors Operational Programme (EU/ERDF funds), through the FCT project PLASTIROADS (PTDC/ECM/119179/2010).info:eu-repo/semantics/publishedVersio

O arquitecto como coleccionador: imagens de pensamento enquanto metodologia de projecto

Dissertação de mestrado integrado em Arquitectura (área de especialização em Cultura Arquitectónica)A ideia do arquitecto como coleccionador constitui o mote para uma dissertação que visa dotar de um enquadramento o pensamento imagético enquanto metodologia de projecto. Da colecção de fragmentos arquitectónicos de John Soane às reproduções de obras de arte reunidas por André Malraux no Musée Imaginaire, perpassa a vontade de construir uma visão coleccionada de um mundo em dispersão a partir do fragmento. Também Rafael Moneo, Eduardo Souto de Moura e Caruso St John construiram colecções de imagens que, por informarem os seus projectos, se afiguram determinantes para a compreensão da obra. Neste sentido, olhar para as suas colecções de referências permite compreender de que modo e com que fim as imagens se transformam em matéria projectual e assim determinar o que caracteriza uma arquitectura fundada nas imagens. Trata-se de uma estratégia projectual que, para limitar a arbitrariedade do processo de concepção, procura nas referências significados culturais para justificar a forma. Uma vez que nada surge do nada, referenciar implica uma segunda leitura sobre algo que já existe, originando, por citação, transformação, ou combinação das referências, diferentes significados e resultados formais. Assim, projectar como quem colecciona resulta numa arquitectura feita por montagens e remontagens, uma vez que a colecção de referências permite reconfigurações infinitas.The idea of the architect as a collector is the motto for a dissertation that aims to provide a framework for imagetic thinking as a project methodology. From John Soane's collection of architectural fragments to the reproductions of works of art assembled by André Malraux at the Musée Imaginaire, the desire to construct a collected vision of a world dispersed from the fragment permeates. Rafael Moneo, Eduardo Souto de Moura and Caruso St John have also built collections of images that, by informing their projects, are crucial for the understanding of their work. In this sense, looking at their reference collections allows us to understand how and for what purpose images become projectual matter and thus determine what characterizes an architecture based on images. It is a project strategy that, in order to limit the arbitrariness of the conception process, seeks in references cultural meanings to justify form. Since nothing comes from nothing, referencing implies a second reading of something that already exists, giving rise to, by citation, transformation, or combination of references, different meanings and formal outcomes. Thus, designing as a collector results in an architecture made by assembling and reassembling, since the collection of references allows for infinite reconfigurations

Waste polymers recycling in high performance asphalt mixtures

Building a road pavement requires large amounts of constituent materials, whose extraction can lead to the devastation of natural resources and causes negative impacts on the environment. As aggregates comprise nearly 90% of asphalt mixtures, their partial substitution by waste thermosetting polymers (12 million tons of waste polymers are presently mislaid into landfills, every year, in Europe) can be considered as a sustainable technology, given that an equivalent performance can be assured. Thus, this study aims on evaluating possible advantages of introducing polyethylene based wastes in asphalt mixtures, namely high density polyethylene (HDPE) and cross-linked polyethylene (PEX), incorporating HDPE as a bitumen modifier and PEX as partial substitute of the aggregates. The laboratory tests carried out in this work showed that the use of HDPE significantly improves the behavior of the asphalt binder/mixture. The use of PEX considerably decreases the density of the mixtures, which can be attractive to lighten structures. The mixtures with PEX have similar performance to the conventional one in terms of water sensitivity, improving the permanent deformation resistance and reducing the temperature susceptibility. In brief, the mixtures incorporating waste polymers could be considered a good technical and environmental alternative for paving works.Portuguese Foundation for Science and Technology (FCT) in the scope of the Strategic Project UI 4047 2011‐201

Utilization of waste materials to improve asphalt mixtures performance

This study aims to develop an innovative bitumen with large quantities of waste materials to improve asphalt mixtures performance. Different amounts of waste motor oil and waste HDPE were added to a new bitumen. The bitumen modified with 10% of waste motor oil and 5% of HDPE showed promising characteristics (high softening point temperatures and penetration slightly higher than the conventional bitumen). After the selection of the most promising modified bitumen, three asphalt mixtures were produced with different bitumens (namely conventional bitumen, commercial modified bitumen and the selected modified bitumen). Beyond that, this modified bitumen improved some mechanical characteristics of the asphalt mixture where it was used, in comparison to conventional and modified asphalt mixtures.Portuguese Government and EU/FSE within a PhD fellowship (SFRH/BD98379/2013) of the FCT, in the scope of POPH/QREN, by FEDER through the Competitiveness Factors Operational Programme (COMPETE) and by national funds through the Portuguese Foundation for Science and Technology (FCT) in the scope of PLASTIROAD Project (PTDC/ECM/119179/2010

Estudo para produção de misturas com betume borracha a menores temperaturas

As misturas com betume borracha precisam de temperaturas mais elevadas no seu processo de fabrico e compactação devido à maior viscosidade deste ligante betuminoso modificado com borracha granulada de pneus usados. Caso contrário, o betume borracha poderá não garantir o correto envolvimento dos agregados e a necessária trabalhabilidade da mistura para a sua correta compactação. As consequências previsíveis relacionam-se com uma maior sensibilidade à água, o que reduz a durabilidade destas misturas e potencia a ocorrência de desagregações superficiais no pavimento. No entanto, o uso de tecnologias temperadas que permitem reduzir as temperaturas de produção e compactação das misturas betuminosas, pode ser uma solução mais sustentável para produção das misturas com betume borracha a menores temperaturas, desde que isso não afete o seu desempenho. Este trabalho consiste no estudo da utilização de uma dessas tecnologias para produzir misturas com betume borracha a menores temperaturas. Assim, estudou-se o efeito que a aplicação de um aditivo surfactante tem nas propriedades dos ligantes com e sem borracha. Em seguida estudou-se a redução de temperatura de produção. Por fim comparou-se o desempenho de misturas betuminosas com betume borracha normais e temperadas. No estudo concluiu-se que é possível reduzir bastante a temperatura de fabrico sem comprometer o desempenho da mistura com betume borracha

Can oil, plastic and RAP wastes have a new life in novel asphalt mixtures?

The pavement recycling allows to reuse reclaimed asphalt pavement (RAP) or other waste materials in new asphalt mixtures for road construction or rehabilitation, thus re-ducing the use of virgin materials (aggregates and bitumen). Thus, the main aim of this study is to minimize the use of natural resources through the reuse of three waste materials: HDPE, mo-tor oil and RAP. Different amounts of waste motor oil and HDPE were added to an asphalt binder with 50% aged bitumen. The best solutions to produce the modified binders (4.5 to 5.0% HDPE and 10 % waste motor oil) performed as well as a conventional bitumen although they only used 35 % of virgin bitumen. Asphalt mixtures with 50 % RAP were produced with the selected modified binders, improving some characteristics in comparison with conventional asphalt mixtures. In conclusion, these wastes can revive in new asphalt mixtures.RDF funds through the Operational Compe titiveness Program – COMPETE and the National funds by FCT – Portuguese Foundation for Science and Technology in the scope of PLASTIROADS Project FCOMP - 01 - 0124 - FEDER - 020335 (PTDC/ECM/119179/20

Desenvolvimento e estudo de ligantes modificados inovadores para infraestruturas de transporte

Este trabalho apresenta alguns projetos desenvolvidos pela presente equipa de investigação relativos ao desenvolvimento de novos materiais para aplicação em pavimentos rodoviários, utilizando resíduos que podem ser valorizados como uma nova matéria‑prima. Desta nova abordagem devem resultar pavimentos betuminosos com melhor desempenho, conjugando ainda vantagens ecológicas e económicas. Assim, apresentam-se três estudos distintos: o primeiro focado na substituição parcial de betume por bio-óleo proveniente da pirólise rápida de resíduos de materiais orgânicos, modificado com granulado de borracha de pneus usados; o segundo consiste na utilização de resíduos plásticos para produção de ligantes modificados, em vez de polímeros virgens, para melhorar o desempenho dos pavimentos; o terceiro também utiliza um resíduo plástico, mas tem como principal objetivo explorar a substituição de parte do betume por outro resíduo, o óleo de motor usado. Neste trabalho são apresentados os principais resultados de desempenho das misturas betuminosas produzidas com estes novos ligantes mais sustentáveis

Plastic waste use as aggregate and binder modifier in open-graded asphalts

Road pavements are very important infrastructures for the Society, but they can cause serious environmental impacts during construction, operation and rehabilitation phases. Thus, it is essential to develop surface paving solutions that promote not only the durability but also a comfortable and safe use. In fact, this work aims to study the properties of new opengraded mixtures for surface layers produced with plastic wastes. First, HDPE and EVA wastes were used as bitumen modifiers, and then another plastic waste (PEX) replaced part of the aggregates. After studying the modified binders, the open-graded mixtures were designed, and then they were tested concerning their particle loss, rutting resistance, surface texture and damping effect. It was concluded that both ways of using the plastic wastes can improve the mechanical and functional properties of the open-graded mixtures related to the pavement performance.ERDF funds through the Operational Competitiveness Program – COMPETE and the National funds by FCT – Portuguese Foundation for Science and Technology in the scope of PLASTIROADS Project FCOMP-01-0124-FEDER-020335 (PTDC/ECM/119179/2010)

Differential effects of left/right neuropathy on rats’ anxiety and cognitive behavior

Chronic pain is frequently accompanied by a deterioration of emotional behavior and cognitive function. A small number of studies in humans concluded that pain-associated negative affect is more pronounced when pain is localized in the left side of the body. It has been suggested that such side bias results from cortical function lateralization. It is not known, however, if other pain-associated behavioral changes are differentially affected by left- and right-sided pain. To test this hypothesis, the performance of rats with a unilateral spared nerve injury neuropathy installed in the left (SNI-L) or in the right (SNI-R) side was compared in anxiety (elevated-plus maze) and cognitive (spatial working and reference memory, attentional set-shifting task, and delay-to-signal impulsivity task) behavioral paradigms. Results show that SNI-L animals presented an increased anxiety-like profile while maintaining preserved cognitive function. On the contrary, SNI-R animals presented cognitive deficits in all tasks except in the reference memory, but displayed a normal anxiety-like profile. Our results show that left- and right-sided neuropathic pain differentially affects emotional behavior, which is in accordance with previous observations in human subjects, both in experimentally induced pain and in chronic pain conditions. Additionally, our results demonstrate that the cognitive function deteriorationThis work was funded by the Portuguese Science Foundation Project PTDC/SAU-NEU/108557/2008, COMPETE and FEDER, and Grant SFRH/BD/29166/200