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When temperatures drop to significantly low levels, road pavements are subjected to thermally-induced stresses, resulting in the appearance of thermal cracking, among other distresses. In these situations, polymers can be used as asphalt binder modifiers to improve certain asphalt binder properties, such as elastic recovery, cohesion, and ductility. Polymers also minimize some of the problems of asphalt mixtures, such as thermal and fatigue cracking and permanent deformation. This work’s objective was to study the behavior of asphalt mixtures at low temperatures, mainly when using modified binders. Thus, three binders were selected and tested: a standard 50/70 penetration grade bitumen and two polymer-modified binders (PMB), obtained by adding, respectively, 2.5% and 5.0% of styrene–butadiene–styrene (SBS) in the 50/70 pen grade bitumen. Then, the PMBs were incorporated into stone mastic asphalt mixtures (namely SMA 11), which were subjected to low-temperature mechanical tests based on the most recent European Standards. The asphalt binders and mixtures evaluated in this work were tested for thermal cracking resistance, creep, elastic recovery, cohesive strength, and ductility strength. Overall, it is concluded that the studied asphalt mixtures with PMB, with just 2.5% SBS, performed adequately at low temperatures down to −20 °C.
Ana Dias; Hugo Silva; Carlos Palha; Joel Oliveira. Low-Temperature Performance of Polymer-Modified Binders in Stone Mastic Asphalts. Infrastructures 2021, 6, 58 .
AMA StyleAna Dias, Hugo Silva, Carlos Palha, Joel Oliveira. Low-Temperature Performance of Polymer-Modified Binders in Stone Mastic Asphalts. Infrastructures. 2021; 6 (4):58.
Chicago/Turabian StyleAna Dias; Hugo Silva; Carlos Palha; Joel Oliveira. 2021. "Low-Temperature Performance of Polymer-Modified Binders in Stone Mastic Asphalts." Infrastructures 6, no. 4: 58.
The development of a linear mixed model to describe the degradation of friction on flexible road pavements to be included in pavement management systems is the aim of this study. It also aims at showing that, at the network level, factors such as temperature, rainfall, hypsometry, type of layer, and geometric alignment features may influence the degradation of friction throughout time. A dataset from six districts of Portugal with 7204 sections was made available by the Ascendi Concession highway network. Linear mixed models with random effects in the intercept were developed for the two-level and three-level datasets involving time, section and district. While the three-level models are region-specific, the two-level models offer the possibility to be adopted to other areas. For both levels, two approaches were made: One integrating into the model only the variables inherent to traffic and climate conditions and the other including also the factors intrinsic to the highway characteristics. The prediction accuracy of the model was improved when the variables hypsometry, geometrical features, and type of layer were considered. Therefore, accurate predictions for friction evolution throughout time are available to assist the network manager to optimize the overall level of road safety.
Adriana Santos; Elisabete Freitas; Susana Faria; Joel Oliveira; Ana Rocha. Prediction of Friction Degradation in Highways with Linear Mixed Models. Coatings 2021, 11, 187 .
AMA StyleAdriana Santos, Elisabete Freitas, Susana Faria, Joel Oliveira, Ana Rocha. Prediction of Friction Degradation in Highways with Linear Mixed Models. Coatings. 2021; 11 (2):187.
Chicago/Turabian StyleAdriana Santos; Elisabete Freitas; Susana Faria; Joel Oliveira; Ana Rocha. 2021. "Prediction of Friction Degradation in Highways with Linear Mixed Models." Coatings 11, no. 2: 187.
Road paving recycling has been acquiring more relevance in society, especially within the paradigm of a circular economy. The addition of waste materials in asphalt mixtures is an excellent solution to face the gradual emergence of a great diversity of waste materials and reduce the production costs. This study aims to evaluate the addition of commercial and laboratory-produced polymer modified binders as rejuvenators in recycled asphalt mixtures with high contents of reclaimed asphalt pavement material (RAP). A commercial polymer modified binder (PMB) and a conventional bitumen modified with 5% of styrene-butadiene-styrene (SBS) or 4% of Regefalt were added to RAP aged bitumen and compared with a rejuvenated binder. Fatigue, permanent deformation and water sensitivity tests carried out on recycled mixtures produced with those binders showed that polymer modified binders could be used as rejuvenators to improve their performance significantly. The recycled asphalt mixture produced with the commercial PMB presented the best mechanical performance. The polymer-modified binders revealed an ageing resistance equivalent to that of the control rejuvenated binder, or slightly better in the case of the final binder with SBS polymer.
Hélder P. Torres; Sara R. M. Fernandes; Carlos D. A. Loureiro; Caroline F. N. Moura; Hugo M. R. D. Silva; Joel R. M. Oliveira. Use of polymer modified binders as rejuvenators in recycled asphalt mixtures. International Journal of Pavement Research and Technology 2020, 13, 654 -664.
AMA StyleHélder P. Torres, Sara R. M. Fernandes, Carlos D. A. Loureiro, Caroline F. N. Moura, Hugo M. R. D. Silva, Joel R. M. Oliveira. Use of polymer modified binders as rejuvenators in recycled asphalt mixtures. International Journal of Pavement Research and Technology. 2020; 13 (6):654-664.
Chicago/Turabian StyleHélder P. Torres; Sara R. M. Fernandes; Carlos D. A. Loureiro; Caroline F. N. Moura; Hugo M. R. D. Silva; Joel R. M. Oliveira. 2020. "Use of polymer modified binders as rejuvenators in recycled asphalt mixtures." International Journal of Pavement Research and Technology 13, no. 6: 654-664.
An increasing interest in the development of alternative solutions based on the use of wastes and residues in the context of soft soils improvement has been observed in the last few years. Most of such research is related to the laboratory characterization of the soil-binder or soil-reinforcement mixtures. However, the viability and impact of the construction process associated with these alternative solutions, as well as the effect of the in situ curing conditions on the mechanical and durability properties of the improved soil cannot be properly assessed in the laboratory. The present paper describes and examines what is, to the best of the authors knowledge, the first full-scale attempt to apply alkali-activated fly ash to the stabilisation of a (sub)base layer. Different types of alkaline activated cement were tested, and soil-cement and soil-lime mixtures were also used, for comparison purposes. An 80 m long (2.5 m wide) full-scale trial was built, divided into 5 sections with different soil-binder combinations, three of which were based on alkaline activated cement. The mechanical properties of all segments were evaluated, on-site and in the laboratory, together with an environmental assessment and a preliminary financial analysis. The results show that the alkaline cement-based materials have mechanical performances similar to traditional binders, with still some margin of optimization due to, their almost embryonic stage of development.
Tiago Miranda; Dinis Leitão; Joel Oliveira; Manuela Corrêa-Silva; Nuno Araújo; João Coelho; Ana Fernández-Jiménez; Nuno Cristelo. Application of alkali-activated industrial wastes for the stabilisation of a full-scale (sub)base layer. Journal of Cleaner Production 2019, 242, 118427 .
AMA StyleTiago Miranda, Dinis Leitão, Joel Oliveira, Manuela Corrêa-Silva, Nuno Araújo, João Coelho, Ana Fernández-Jiménez, Nuno Cristelo. Application of alkali-activated industrial wastes for the stabilisation of a full-scale (sub)base layer. Journal of Cleaner Production. 2019; 242 ():118427.
Chicago/Turabian StyleTiago Miranda; Dinis Leitão; Joel Oliveira; Manuela Corrêa-Silva; Nuno Araújo; João Coelho; Ana Fernández-Jiménez; Nuno Cristelo. 2019. "Application of alkali-activated industrial wastes for the stabilisation of a full-scale (sub)base layer." Journal of Cleaner Production 242, no. : 118427.
The energy or fuel consumption of the millions of vehicles that daily operate in road pavements has a significant economic and environmental impact on the use phase of road infrastructures regarding their life cycle analysis. Therefore, new solutions should be studied to reduce the vehicles energy consumption, namely due to the tire-pavement interaction, and contribute towards the sustainable development. This study aims at estimating the energy consumption due to the rolling resistance of tires moving over pavements with distinct surface characteristics. Thus, different types of asphalt mixtures were used in the surface course to determine the main parameters influencing the energy consumption. A laboratory scale prototype was developed explicitly for this evaluation. Data mining techniques were used to analyze the experimental results due to the complex correlation between the data collected during the tests, providing meaningful results. In particular, the artificial neural network allowed to obtain models with excellent capacity to estimate energy consumption. A sensitive analysis was carried out with a five input parameter model, which showed that the main parameters controlling the energy consumption are the vehicle speed and the mean texture depth.
João Paulo C. Araújo; Carlos A.O. Palha; Francisco F. Martins; Hugo M.R.D. Silva; Joel R.M. Oliveira. Estimation of energy consumption on the tire-pavement interaction for asphalt mixtures with different surface properties using data mining techniques. Transportation Research Part D: Transport and Environment 2018, 67, 421 -432.
AMA StyleJoão Paulo C. Araújo, Carlos A.O. Palha, Francisco F. Martins, Hugo M.R.D. Silva, Joel R.M. Oliveira. Estimation of energy consumption on the tire-pavement interaction for asphalt mixtures with different surface properties using data mining techniques. Transportation Research Part D: Transport and Environment. 2018; 67 ():421-432.
Chicago/Turabian StyleJoão Paulo C. Araújo; Carlos A.O. Palha; Francisco F. Martins; Hugo M.R.D. Silva; Joel R.M. Oliveira. 2018. "Estimation of energy consumption on the tire-pavement interaction for asphalt mixtures with different surface properties using data mining techniques." Transportation Research Part D: Transport and Environment 67, no. : 421-432.
The use of plastic wastes as an alternative to virgin polymers can be a remarkable environmentally friendly idea for road paving construction or rehabilitation. Therefore, this study aimed at assessing the potential benefits of modifying a conventional 35/50 penetration grade bitumen, with uncontaminated waste polymers (ethylene vinyl acetate and high-density polyethylene) carefully selected from plastic recycling plants. A virgin polymer (styrene-butadienestyrene) was also used as reference material since it is the polymer most commonly used for bitumen modification. The performance (physical, storage stability, and rheological properties) and morphologic characteristics of the different waste polymer modified binders were thoroughly evaluated and compared with those of the 35/50 bitumen and the virgin polymer modified binder. It was concluded that recycled EVA and virgin SBS modified binders could perform similarly, namely regarding their viscosity and rheological properties. Furthermore, EVA modified binder presented slightly better storage stability probably due to its homogeneous dispersion. The recycled HDPE modified bitumen reveals some promising physical properties (associated with rutting resistance), but it presents the worst resilience and creep recovery. The outcome of this work is the development of new asphalt binders modified with waste polymers as reliable alternatives for road paving activities due to their excellent performance, comparable to that obtained with the most commonly used virgin polymer.
Liliana M.B. Costa; Hugo M.R.D. Silva; Joana Peralta; Joel R.M. Oliveira. Using waste polymers as a reliable alternative for asphalt binder modification – Performance and morphological assessment. Construction and Building Materials 2018, 198, 237 -244.
AMA StyleLiliana M.B. Costa, Hugo M.R.D. Silva, Joana Peralta, Joel R.M. Oliveira. Using waste polymers as a reliable alternative for asphalt binder modification – Performance and morphological assessment. Construction and Building Materials. 2018; 198 ():237-244.
Chicago/Turabian StyleLiliana M.B. Costa; Hugo M.R.D. Silva; Joana Peralta; Joel R.M. Oliveira. 2018. "Using waste polymers as a reliable alternative for asphalt binder modification – Performance and morphological assessment." Construction and Building Materials 198, no. : 237-244.
The new environmental targets set to save natural resources and recover waste materials have been the basis for several scientific studies in different research areas. Consequently, this work aims at developing recycled stone mastic asphalt mixtures with high rates of waste materials, including reclaimed asphalt pavements, waste engine oil products, waste polyethylene and crumb rubber. This new solution was compared with a conventional stone mastic asphalt mixture. Several blends of high penetration bitumens modified with waste materials and reclaimed aged bitumen were evaluated through basic and advanced tests, and the most promising solutions were selected to produce recycled stone mastic asphalt mixtures for further characterization. The water sensitivity, permanent deformation and fatigue cracking performance of those mixtures incorporating high rates of different waste materials were generally improved. The exceptional behaviour of these recycled mixtures together with the high incorporation rate of waste materials demonstrate the innovative character of these solutions for the road paving industry.
Sara R.M. Fernandes; Hugo M.R.D. Silva; Joel R.M. Oliveira. Recycled stone mastic asphalt mixtures incorporating high rates of waste materials. Construction and Building Materials 2018, 187, 1 -13.
AMA StyleSara R.M. Fernandes, Hugo M.R.D. Silva, Joel R.M. Oliveira. Recycled stone mastic asphalt mixtures incorporating high rates of waste materials. Construction and Building Materials. 2018; 187 ():1-13.
Chicago/Turabian StyleSara R.M. Fernandes; Hugo M.R.D. Silva; Joel R.M. Oliveira. 2018. "Recycled stone mastic asphalt mixtures incorporating high rates of waste materials." Construction and Building Materials 187, no. : 1-13.
The need to save natural resources has paradigmatic attitude changes, such as the need to value waste materials in order to reduce landfill and minimize the use of raw materials. The objective of this work is to show the contribution of existing literature about the incorporation of industrial wastes in asphalt pavements. Thus, some of the main industrial wastes that can be incorporated in asphalt mixtures as aggregate substitute are steel slag, foundry sand and fly ash. This wastes are produced on a large scale on the planet, and the literature shows that, when treated for use in road pavements, their mechanical properties are similar or superior to conventional aggregates. Thus, according to the studies presented here, the incorporation rates vary from 5 to 15% for foundry sand, 70% for steel slag and 30% for fly ash. When incorporated in asphalt pavements, the dangerous elements may be encapsulated in the mixture, reducing their environmental toxicity.
Lucas Pereira Do Nascimento; Joel R. M. Oliveira; Cândida Vilarinho. Use of Industrial Waste as a Substitute for Conventional Aggregates in Asphalt Pavements: A Review. Lecture Notes in Electrical Engineering 2018, 690 -696.
AMA StyleLucas Pereira Do Nascimento, Joel R. M. Oliveira, Cândida Vilarinho. Use of Industrial Waste as a Substitute for Conventional Aggregates in Asphalt Pavements: A Review. Lecture Notes in Electrical Engineering. 2018; ():690-696.
Chicago/Turabian StyleLucas Pereira Do Nascimento; Joel R. M. Oliveira; Cândida Vilarinho. 2018. "Use of Industrial Waste as a Substitute for Conventional Aggregates in Asphalt Pavements: A Review." Lecture Notes in Electrical Engineering , no. : 690-696.
The reduction in the use of natural and finite resources and the reuse of waste materials are current concerns of different research areas. Therefore, the main aim of this study is to develop enhanced modified bitumens with waste engine oil and recycled engine oil bottoms combined with polymers (waste polyethylene, crumb rubber and styrene-butadienestyrene), in order to minimize the use of bitumen. After a thermochemical characterization, different compositions were studied with penetration, softening point and viscosity tests. The bitumens modified with waste engine oil products and polymers have similar penetration values, and softening point temperatures higher than those of commercially modified binders. A rheological analysis of the most encouraging solutions showed low thermal susceptibility, high values of high temperature PG and low non-recoverable creep compliance values, which could indicate a promising performance using high amounts of waste materials.Portuguese Government and EU/FSE within a FCT PhD grant (SFRH/BD98379/2013), in the scope of POPH/QREN, as well as the funding by ERDF through the Competitiveness Factors Operational Programme (COMPETE) and by national funds through the Portuguese Foundation for Science and Technology (FCT) in the scope of PLASTIROADS Project (PTDC/ECM/119179/2010)info:eu-repo/semantics/publishedVersio
Sara R.M. Fernandes; Hugo M.R.D. Silva; Joel R.M. Oliveira. Developing enhanced modified bitumens with waste engine oil products combined with polymers. Construction and Building Materials 2018, 160, 714 -724.
AMA StyleSara R.M. Fernandes, Hugo M.R.D. Silva, Joel R.M. Oliveira. Developing enhanced modified bitumens with waste engine oil products combined with polymers. Construction and Building Materials. 2018; 160 ():714-724.
Chicago/Turabian StyleSara R.M. Fernandes; Hugo M.R.D. Silva; Joel R.M. Oliveira. 2018. "Developing enhanced modified bitumens with waste engine oil products combined with polymers." Construction and Building Materials 160, no. : 714-724.
The reuse of waste materials in asphalt mixtures has been recently investigated, in order to develop new sustainable solutions for the road-paving industry. Such materials should improve the mechanical performance and provide safe/comfortable pavement surface courses for road users, without compromising their environmental performance. Thus, the aim of this study is to evaluate the mechanical, surface and environmental properties of stone mastic asphalt (SMA) mixtures produced with forward-looking asphalt binders incorporating waste materials. These binders were designed to maximise the waste material content using motor oil, high-density polyethylene, styrene–butadiene–styrene and crumb rubber, while performing so well as a commercial modified bitumen. Finally, the overall performance of the SMA mixtures produced with the selected binders was evaluated. It was concluded that these mixtures improve the water sensitivity, fatigue cracking and permanent deformation performance. The requirements for macrotexture, skid resistance and presence of heavy metals in leachates of these mixtures were similarly fulfilled. Thus, this work shows that new asphalt mixtures with waste materials can be used in road-paving works to improve the performance without compromising human and environmental safety.
Sara Fernandes; Hugo M. R. D. Silva; Joel R. M. Oliveira. Mechanical, surface and environmental evaluation of stone mastic asphalt mixtures with advanced asphalt binders using waste materials. Road Materials and Pavement Design 2017, 20, 316 -333.
AMA StyleSara Fernandes, Hugo M. R. D. Silva, Joel R. M. Oliveira. Mechanical, surface and environmental evaluation of stone mastic asphalt mixtures with advanced asphalt binders using waste materials. Road Materials and Pavement Design. 2017; 20 (2):316-333.
Chicago/Turabian StyleSara Fernandes; Hugo M. R. D. Silva; Joel R. M. Oliveira. 2017. "Mechanical, surface and environmental evaluation of stone mastic asphalt mixtures with advanced asphalt binders using waste materials." Road Materials and Pavement Design 20, no. 2: 316-333.
The mechanical performance of a typical surface course mixture, modified with two different plastic wastes, both via the wet and dry processes, was evaluated in this study. Water sensitivity, rutting resistance, stiffness modulus, and fatigue cracking resistance tests were used. The results obtained indicated that the polymer-modified mixtures showed similar or improved performance when compared with that of a conventional control mixture produced with a harder virgin grade bitumen, not always available, or available at higher costs, in several countries. Thus, modifying asphalt mixtures with these plastic wastes can be an economical and ecological alternative for paving works. Moreover, the mixtures produced via the dry process showed increased water sensitivity and stiffness modulus properties. This holds out new possibilities for use of polymer-modified mixtures, especially in developing countries, because it widens the possibility of using locally available bitumen, of variable quality, for producing mixtures with higher performance. This can be achieved at real scale with no major extra costs because the dry process does not require modification of typical asphalt plants.
Mauro Ranieri; Liliana Costa; Joel R. M. Oliveira; Hugo Manuel Ribeiro Dias Da Silva; Clara Celauro. Asphalt Surface Mixtures with Improved Performance Using Waste Polymers via Dry and Wet Processes. Journal of Materials in Civil Engineering 2017, 29, 04017169 .
AMA StyleMauro Ranieri, Liliana Costa, Joel R. M. Oliveira, Hugo Manuel Ribeiro Dias Da Silva, Clara Celauro. Asphalt Surface Mixtures with Improved Performance Using Waste Polymers via Dry and Wet Processes. Journal of Materials in Civil Engineering. 2017; 29 (10):04017169.
Chicago/Turabian StyleMauro Ranieri; Liliana Costa; Joel R. M. Oliveira; Hugo Manuel Ribeiro Dias Da Silva; Clara Celauro. 2017. "Asphalt Surface Mixtures with Improved Performance Using Waste Polymers via Dry and Wet Processes." Journal of Materials in Civil Engineering 29, no. 10: 04017169.
Pavements heavily influence the management costs in highway networks. Operating pavements represents a challenging task involving complex decisions on the application of maintenance actions to keep them at a reasonable level of performance. The major difficulty in applying computational tools to support decision making lies in a large number of pavement sections as a result of a high length of road networks. This paper addresses maintenance scheduling for pavements by consolidating this task into two stages. In each stage, multiobjective optimization is used to optimize maintenance schedules. The main motivation is to obtain a computationally treatable model for large road networks. The first stage is defined by a collection of pavement sections composing the road network. In this stage, the performance and maintenance models are addressed. These models account for uncertainties in the future performance and effects of maintenance by defining model parameters as random variables. The second stage refers to combining maintenance schedules for individual sections to determine the optimal maintenance plan at the network level. The results obtained for the real road network demonstrate the validity and usefulness of the proposed framework. Moreover, this framework is general and can be extended to different types of infrastructure assets.
Roman Denysiuk; André Moreira; José C. Matos; Joel R. M. Oliveira; Adriana Santos. Two-Stage Multiobjective Optimization of Maintenance Scheduling for Pavements. Journal of Infrastructure Systems 2017, 23, 04017001 .
AMA StyleRoman Denysiuk, André Moreira, José C. Matos, Joel R. M. Oliveira, Adriana Santos. Two-Stage Multiobjective Optimization of Maintenance Scheduling for Pavements. Journal of Infrastructure Systems. 2017; 23 (3):04017001.
Chicago/Turabian StyleRoman Denysiuk; André Moreira; José C. Matos; Joel R. M. Oliveira; Adriana Santos. 2017. "Two-Stage Multiobjective Optimization of Maintenance Scheduling for Pavements." Journal of Infrastructure Systems 23, no. 3: 04017001.
The environmental concern about waste generation and the gradual decrease of oil reserves has led the way to finding new waste materials that may partially replace the bitumens used in the road paving industry. Used motor oil from vehicles is a waste product that could answer that demand, but it can also drastically reduce the viscosity, increasing the asphalt mixture’s rutting potential. Therefore, polymer modification should be used in order to avoid compromising the required performance of asphalt mixtures when higher amounts of waste motor oil are used. Thus, this study was aimed at assessing the performance of an asphalt binder/mixture obtained by replacing part of a paving grade bitumen (35/50) with 10% waste motor oil and 5% styrene-butadiene-styrene (SBS) as an elastomer modifier. A comparison was also made with the results of a previous study using a blend of bio-oil from fast pyrolysis and ground tire rubber modifier as a partial substitute for usual PG64-22 bitumen. The asphalt binders were tested by means of Fourier infrared spectra and dynamic shear rheology, namely by assessing their continuous high-performance grade. Later, the water sensitivity, fatigue cracking resistance, dynamic modulus and rut resistance performance of the resulting asphalt mixtures was evaluated. It was concluded that the new binder studied in this work improves the asphalt mixture’s performance, making it an excellent solution for paving works.
Sara Fernandes; Joana Peralta; Joel R. M. Oliveira; R. Christopher Williams; Hugo M. R. D. Silva. Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers. Applied Sciences 2017, 7, 794 .
AMA StyleSara Fernandes, Joana Peralta, Joel R. M. Oliveira, R. Christopher Williams, Hugo M. R. D. Silva. Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers. Applied Sciences. 2017; 7 (8):794.
Chicago/Turabian StyleSara Fernandes; Joana Peralta; Joel R. M. Oliveira; R. Christopher Williams; Hugo M. R. D. Silva. 2017. "Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers." Applied Sciences 7, no. 8: 794.
Due to the current need for more sustainable production processes and construction materials, foamed bitumen has become one of the most interesting solutions for asphalt paving works, both for new (warm mix) and recycled asphalt mixtures (warm recycled mix). However, significant work still needs to be carried out in order to fully understand the performance of foamed bitumens, and their adequacy for incorporation into asphalt mixtures with different amounts of reclaimed materials, which is the main objective of this work. Three types of bitumen, with increasing penetration grades were selected in order to evaluate their foaming properties, namely their expansion ratio and half-life, as well as the foam index assessed using the foam decay curves obtained through a semi-automated process. After determining the most suitable composition of each foamed bitumen (water content, temperature, foam stabilizing additive content), these were incorporated into asphalt mixtures with 0%, 30% and 50% reclaimed asphalt material. As the amount of reclaimed material increased, the penetration grade of the new bitumen added was also increased, in order to compensate the lost properties of the aged binder. The suitability of these solutions was assessed through water sensitivity tests, and it was concluded that the proposed approach is adequate to obtain long-lasting solutions. Moreover, it became evident that foamed bitumens perform better when incorporated into recycled asphalt mixtures.The authors would like to acknowledge the contribution of Galp and Elevo Group for supplying the binders and the RAP material used in this study. This work was funded by ERDF funds through the Operational Competitiveness Program – COMPETE in the scope of the Project “Energy Efficiency and Environmental Design of Bituminous Mixtures and Reducing Emissions of Greenhouse Gases” (SI Innovation Project 7603). Thanks are also due to the Foundation for Science and Technology (FCT) for funding allocated to the SFRH/BD/85448/2012 PhD grant.info:eu-repo/semantics/publishedVersio
Liliana P.F. Abreu; Joel Oliveira; Hugo Silva; Daniela Palha; Paulo V. Fonseca. Suitability of different foamed bitumens for warm mix asphalts with increasing recycling rates. Construction and Building Materials 2017, 142, 342 -353.
AMA StyleLiliana P.F. Abreu, Joel Oliveira, Hugo Silva, Daniela Palha, Paulo V. Fonseca. Suitability of different foamed bitumens for warm mix asphalts with increasing recycling rates. Construction and Building Materials. 2017; 142 ():342-353.
Chicago/Turabian StyleLiliana P.F. Abreu; Joel Oliveira; Hugo Silva; Daniela Palha; Paulo V. Fonseca. 2017. "Suitability of different foamed bitumens for warm mix asphalts with increasing recycling rates." Construction and Building Materials 142, no. : 342-353.
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.
Liliana M. B. Costa; Joana Peralta; Joel R. M. Oliveira; Hugo M. R. D. Silva. A New Life for Cross-Linked Plastic Waste as Aggregates and Binder Modifier for Asphalt Mixtures. Applied Sciences 2017, 7, 603 .
AMA StyleLiliana M. B. Costa, Joana Peralta, Joel R. M. Oliveira, Hugo M. R. D. Silva. A New Life for Cross-Linked Plastic Waste as Aggregates and Binder Modifier for Asphalt Mixtures. Applied Sciences. 2017; 7 (6):603.
Chicago/Turabian StyleLiliana M. B. Costa; Joana Peralta; Joel R. M. Oliveira; Hugo M. R. D. Silva. 2017. "A New Life for Cross-Linked Plastic Waste as Aggregates and Binder Modifier for Asphalt Mixtures." Applied Sciences 7, no. 6: 603.
The increasing environmental concern about waste materials and the necessity of improving the performance of asphalt mixtures prompted the study of incorporating different waste materials in conventional bitumen. The reuse of waste materials can present benefits at an environmental and economic level, and some wastes can be used to improve the pavement performance. Thus, the purpose of this study is to evaluate the incorporation of different waste materials in bitumen, namely waste motor oil and different polymers. In order to accomplish this goal, 10% of waste motor oil and 5% of polymers (high density polyethylene, crumb rubber and styrene-butadiene-styrene) were added to a conventional bitumen and the resulting modified bitumens were characterized through basic and rheological tests. From this work, it can be concluded that the incorporation of different waste materials improve some important properties of the conventional bitumen. Such improvements might indicate a good behaviour at medium/high temperatures and an increase of fatigue and rutting resistance. Therefore, these modified bitumens with waste materials can contribute to a sustainable development of road paving industry due to their performance and environmental advantages.The authors gratefully acknowledge the funding by the Portuguese Government and EU/FSE within a FCT PhD grant (SFRH/BD98379/2013), in the scope of POPH/QREN, as well as the funding 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). The authors would also like to acknowledge the contribution of the company ELEVO Group through the project “Energy Efficiency and Environmental Design of Bituminous Mixtures to Reduce Emissions of Greenhouse Gases” (QREN-SI 090528), carried out in cooperation with the University of Minho
Sara Fernandes; Liliana Costa; Hugo Silva; Joel Oliveira. Effect of incorporating different waste materials in bitumen. Ciência & Tecnologia dos Materiais 2017, 29, e204 -e209.
AMA StyleSara Fernandes, Liliana Costa, Hugo Silva, Joel Oliveira. Effect of incorporating different waste materials in bitumen. Ciência & Tecnologia dos Materiais. 2017; 29 (1):e204-e209.
Chicago/Turabian StyleSara Fernandes; Liliana Costa; Hugo Silva; Joel Oliveira. 2017. "Effect of incorporating different waste materials in bitumen." Ciência & Tecnologia dos Materiais 29, no. 1: e204-e209.
Liliana Abreu; Joel Oliveira; Hugo Silva; Catarina Silva; Daniela Palha; Paulo Fonseca. Foamed bitumen: an alternative way of producing asphalt mixtures. Ciência & Tecnologia dos Materiais 2017, 29, e198 -e203.
AMA StyleLiliana Abreu, Joel Oliveira, Hugo Silva, Catarina Silva, Daniela Palha, Paulo Fonseca. Foamed bitumen: an alternative way of producing asphalt mixtures. Ciência & Tecnologia dos Materiais. 2017; 29 (1):e198-e203.
Chicago/Turabian StyleLiliana Abreu; Joel Oliveira; Hugo Silva; Catarina Silva; Daniela Palha; Paulo Fonseca. 2017. "Foamed bitumen: an alternative way of producing asphalt mixtures." Ciência & Tecnologia dos Materiais 29, no. 1: e198-e203.
The aim of this study is evaluating the interaction between several base pen grade asphalt binders (35/50, 50/70, 70/100, 160/220) and two different recycled plastics (EVA and HDPE), for a set of new polymer modified binders produced with different amounts of both recycled plastics. After analysing the results obtained for the several polymer modified binders evaluated in this study, including a commercial modified binder, it can be concluded that the new PMBs produced with the base bitumen 70/100 and 5% of each recycled plastic (HDPE or EVA) results in binders with very good performance, similar to that of the commercial modified binder.This work was funded by FEDER funds through the Operational Programme for Competitiveness Factors - COMPETE and National Funds through FCT - Foundation for Science and Technology under the project PLASTIROADS (PTDC/ECM/119179/2010). The authors would also like to acknowledge the contribution of the company ELEVO Group through the project “Energy Efficiency and Environmental Design of Bituminous Mixtures to Reduce Emissions of Greenhouse Gases” (QREN-SI 090528), carried out in cooperation with the University of Minho.info:eu-repo/semantics/publishedVersio
Liliana Costa; Sara Fernandes; Hugo Silva; Joel Oliveira. Study of the interaction between asphalt and recycled plastics in new polymer modified binders (PMB). Ciência & Tecnologia dos Materiais 2017, 29, e192 -e197.
AMA StyleLiliana Costa, Sara Fernandes, Hugo Silva, Joel Oliveira. Study of the interaction between asphalt and recycled plastics in new polymer modified binders (PMB). Ciência & Tecnologia dos Materiais. 2017; 29 (1):e192-e197.
Chicago/Turabian StyleLiliana Costa; Sara Fernandes; Hugo Silva; Joel Oliveira. 2017. "Study of the interaction between asphalt and recycled plastics in new polymer modified binders (PMB)." Ciência & Tecnologia dos Materiais 29, no. 1: e192-e197.
Pavement maintenance and rehabilitation programming requires the consideration of conflicting objectives to optimize its life-cycle costs. While there are several approaches to solve multiobjective problems for pavement management systems, when user costs or environmental impacts are considered the optimal solutions are often impractical to be accepted by road agencies, given the dominating share of user costs in the total life-cycle costs. This paper presents a two-stage optimization methodology that considers maximization of pavement quality and minimization of agency costs as the objectives to be optimized at the pavement section level, while at the network level, the objectives are to minimize agency and user costs. The main goal of this approach is to provide decision makers with a range of optimal solutions from which a practically implementable one could be selected by the agency. A sensitivity analysis and some trade-off graphics illustrate the importance in balancing all the objectives to obtain reasonable solutions for highway agencies. Multiobjective optimization problems at both levels are solved using genetic algorithms. The results of a case study indicate the applicability of the methodology.
André Moreira; Tien F. Fwa; Joel Oliveira; Lino Costa. Coordination of User and Agency Costs Using Two-Level Approach for Pavement Management Optimization. Transportation Research Record: Journal of the Transportation Research Board 2017, 2639, 110 -118.
AMA StyleAndré Moreira, Tien F. Fwa, Joel Oliveira, Lino Costa. Coordination of User and Agency Costs Using Two-Level Approach for Pavement Management Optimization. Transportation Research Record: Journal of the Transportation Research Board. 2017; 2639 (1):110-118.
Chicago/Turabian StyleAndré Moreira; Tien F. Fwa; Joel Oliveira; Lino Costa. 2017. "Coordination of User and Agency Costs Using Two-Level Approach for Pavement Management Optimization." Transportation Research Record: Journal of the Transportation Research Board 2639, no. 1: 110-118.
One of the main awareness for a road infrastructures manager is to increase its efficiency under limited resources. Pavement Management Systems aim, at last, to support road administrations in the decision-making process regarding its management policy and long-term strategies for maintenance and rehabilitation activities. While several road administrations are putting efforts in developing optimisation methodologies to enhance their decision making process, many still lack of data that allows the development of reliable prediction models for pavement performance. This is a key aspect to develop and test decision-making methodologies. Although there are several prediction models available in the literature, their practical applications are often limited to the very specific network from which data were retrieved at first and to a specific performance indicator (PI). This paper presents a practical application of a Markov model to predict the evolution of five PIs – cracking, skid resistance, bearing capacity, longitudinal evenness and transverse evenness – and consequent combined PIs, using historical data from an extensive pavement database. The conversion for PIs is made through a standardisation procedure proposed by an European COST Action, which may be considered a reference classification system for road administrations. The presented model is intended to be an useful input for researchers and administrations willing to develop and test different optimisation approaches.
André Moreira; Joaquim Tinoco; Joel R. M. Oliveira; Adriana Santos. An application of Markov chains to predict the evolution of performance indicators based on pavement historical data. International Journal of Pavement Engineering 2016, 19, 937 -948.
AMA StyleAndré Moreira, Joaquim Tinoco, Joel R. M. Oliveira, Adriana Santos. An application of Markov chains to predict the evolution of performance indicators based on pavement historical data. International Journal of Pavement Engineering. 2016; 19 (10):937-948.
Chicago/Turabian StyleAndré Moreira; Joaquim Tinoco; Joel R. M. Oliveira; Adriana Santos. 2016. "An application of Markov chains to predict the evolution of performance indicators based on pavement historical data." International Journal of Pavement Engineering 19, no. 10: 937-948.