Papers
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Characterization of soil treated with alkali-activated cement in large-scale specimens
Soil improvement with hydraulic binders is currently used in practice because of the advantages of using the local soil enhancing its geotechnical properties. However, environmental issues related to quicklime applications and carbon-dioxide emissions associated to Portland cement production encouraged the development of new binders. In this work, alkaline-activated cement (AAC) synthetized by fly ash and an alkaline solution was used to stabilize silty sand. The behavior of the treated soil was evaluated performing tests on a physical model and the results were compared to laboratory data to define its compaction, strength, and stiffness properties. Those tests include nuclear density gauge measurements, light falling weight deflectometer tests, and plate load tests, whereas unconfined compression tests with unload
Year: 2017
Number Pages:
618-629pp.
Author(s): Cruz, N.; Rios, S.; Fortunato, E.; Rodrigues, C.; Cruz, J.; Mateus, C.; Ramos, C.
: Geotechnical Testing Journal
Editor: ASTM
Volume:
Vol. 40, No. 4.
DOI:
10.1520/GTJ20160211
Keywords: Controlled condition chamber; Real-scale demonstration; Physical model; Soil improvement; Alkali-activated cement; Fly ash
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INFLUÊNCIA DO FÍLER NO COMPORTAMENTO DE MASTIQUES BETUMINOSOS
No âmbito de uma dissertação de mestrado realizada em parceriaentre a Faculdade de Ciências e Tecnologias da Universidade Novade Lisboa (FCT-UNL) e o Laboratório Nacional de Engenharia Civil(LNEC) sobre a caracterização de fíleres para a utilização em misturasbetuminosas, foram avaliadas as propriedades destes materiais, deforma a validar as que apresentam maior influência no comportamento dos mastiques e das misturas betuminosas, tendo sido estudada uma metodologia alternativa de avaliação da capacidadede incremento da viscosidade do mastique betuminoso. De formaa avaliar o efeito do fíler no incremento da viscosidade do mastiquebetuminoso, estes foram avaliados com recurso ao ensaio de determinação da temperatura de amolecimento, sendo posteriormentecalculada a variação desta temperatura em relação ao betume original.Neste estudo além de serem estudados os fíleres tradicionais,que se encontram contemplados nas especificações utilizadas a nívelnacional para estes materiais, foram também avaliados materiais alternativos,dado o interesse verificado ao longo dos últimos anos emaumentar a reutilização de subprodutos industriais e de resíduos deconstrução e demolição.
Year: 2017
Author(s): Antunes, Vítor; Freire, A. C.; Quaresma, Luis.
: Revista TECH ITT
Editor: Revista TECH ITT
Volume:
nº40, volume 15.
Keywords: Fíleres alternativos, Mastiques betuminosos, Poder absorvente, Temperatura de amolecimento
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A contribution for integrated analysis of railway track performance at transition zones and other discontinuities
Railway infrastructure managers can benefit from more advanced tools to analyse available data in asset management activities. In this work, the authors present a contribution to anticipating the development of critical locations in railway tracks, such as transition zones and other singularities, using a novel method to analyse railway track performance. Information on track geometry records, namely the evolution on the longitudinal level of a case study, is integrated with information from a numerical study on the effect of track irregularities on the train-track system and with characteristics of the track superstructure and substructure. The approach involves analysing the information in terms of the length of the defects and respective amplitudes to identify locations suggesting: higher derailment risk, faster track degradation and lower passenger comfort. The application of this method suggested that track singularities and changes in the substructure seem to trigger rapid track degradation. The consideration of shorter moving windows in the analysis of the standard deviation of the longitudinal level showed to be a promising approach to assess the degradation rates at track singularities. The proposed method, in association with other tools can provide crucial information for railway infrastructure managers.
Year: 2016
Number Pages:
699-709pp.
Author(s): Paixão, A.; Fortunato, E.; Calçada, R.
: Construction and Building Materials
Editor: Elsevier B.V.
Volume:
111.
Keywords: Transition zones; Track degradation; Deformation modulus EV2; Longitudinal level; Track geometry; Railway track
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Assessment of Environmental Hazardous of Construction and Demolition Recycled Materials (C&DRM) from Laboratory and Field Leaching Tests Application in Road Pavement Layers
A research project aiming to contribute to the sustainable implementation of recycling of Construction and Demolition Waste (C&DW) in road pavements is ongoing. The use of Construction and Demolition Recycled Materials (C&DRM) in road pavements is envisaged as a solution with major environmental and economic benefits. Their application as unbound granular material in pavement layers (base, sub-base and capping layers) also has the advantage to allow the incorporation of largeamounts of this type of materials, even coming from different sources. Engineering and environmental performance of these materials are being assessed through laboratory tests and field tests. The evaluation of the environmental hazardous of C&DRM is based in their leachability from compliance (batch test) and basic characterisation (column test and lysimeter test) leach tests. The results already obtained in leaching tests are presented and discussed in the paper. In case of compliance leach test,the results are compared with leaching limit values defined in the Portuguese legislation for waste acceptable at landfills for inert waste.
Year: 2016
Number Pages:
204-211.
Author(s): Roque, A. J.; Martins, I. M.; Freire, A. C.; Neves, J.; Antunes, M. L.
: Procedia Engineering
Editor: Elsevier
Volume:
Volume 143.
Keywords: Construction and demolition recycled materials, Road pavement, Unbound granular layers, Leaching
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Main results of the questionnaire for portuguese entities potential users of Construction and Demolition Recycled Materials (C&DRM)
Within the framework of the activities of the working group GT1 of the Portuguese Commission onTransportation Geotechnics
Year: 2016
Number Pages:
82-89pp.
Author(s): Freire, A. C.; Martins, I. M.; Ferreira, C.; Gonçalves, J.; Roque, A. J.
: Procedia Engineering
Editor: Elsevier
Volume:
Vol. 143.
Keywords: National distribution; Transport infrastructures; Questionnaire; Construction and demolition recycled materials (C&DRM)
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A numerical study on the influence of backfill settlements in the train/track interaction at transition zones to railway bridges
Railway track degrades more quickly in the transition zones between embankments and bridges, mostly due to thedevelopment of settlements in the backfill. This amplifies the dynamic train/track interaction forces and accelerates thedeterioration of the components of both the track and the vehicles. Consequently, it induces additional maintenancecosts, reduces passenger comfort and, ultimately, it may affect train safety at transition zones. To address this problemand to obtain more insight into the influence of the settlement profiles of the backfill in the train/track system, nonlineardynamic analyses were performed using a transition zone model to simulate different settlement profiles of the backfill.In some cases, the results showed significant amplifications of axle accelerations and loads. In general, the greaterthe number of hanging sleepers and their gap sizes, the higher the vertical accelerations of the sleepers and thelarger the vertical contact forces between the sleepers and the ballast layer. Settlement profiles associated with backfillswith a wedge shape seem to limit these negative aspects.
Year: 2015
Number Pages:
13p.
Author(s): Paixão, A.; Fortunato, E.; Calçada, R.
: Journal of Rail and Rapid Transit
Editor: Institution of Mechanical Engineers
Keywords: Railway bridges; Train/track interaction; Numerical modelling; Differential settlements; Transition zones; Railway track
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Design and construction of backfills for railway track transition zones
The initial geometry of a railway track continually degrades over its life-cycle. Changes in the track alignment give rise tovariations in the dynamic axle load which accelerate track degradation, with consequences for maintenance and avail-ability of the line. This behaviour is particularly evident at some critical locations that are associated with abrupt changesin the track
Year: 2015
Number Pages:
58-70 (13P).
Author(s): Paixão, A.; Fortunato, E.; Calçada, R.
: Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit
Editor: SAGE Publications on behalf of IMechE
Keywords: Performance-based tests; Track degradation; Vertical stiffness; Backfill design and construction; Railway transition zones; Deformation modulus; Cyclic load triaxial tests
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On the use of under sleeper pads in transition zones at railway underpasses: experimental field testing
The railway track at transition zones to bridges or to other structures usually requires considerably more interventions tomaintain the same open track service quality and safety levels. Under sleeper pads (USP) have been reported to contribute toreduce degradation and frequency of maintenance operations in open ballasted tracks, and recent numerical studies havesuggested its use in transition zones. In this study, the in
Year: 2015
Number Pages:
112-128pp..
Author(s): Paixão, A.; Ribeiro , C.; Pinto, N.; Fortunato, E.; Calçada, R.
: Structure and Infrastructure Engineering
Editor: Taylor & Francis
Volume:
11(2).
Keywords: Track monitoring; Feld measurements; Under sleeper pads; Transition zones; Railway underpasses
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Rock joint topography: three-dimensional scanning and numerical analysis
Joints are the most defining features of fractured rock masses. It has been well established thatjoint behaviour is mainly defined by wall topography, which is difficult to measure and define. Previousworks have employed both contact and non-contact scanning methods and multiple approaches tothe analysis of rock surfaces, but a majority focused exclusively on individual surface characterisationwithout appraising wall
Year: 2015
Number Pages:
318
Author(s): Resende, R.; Muralha, J.; Ramos, A.; Fortunato, E.
: Géotechnique Letters
Editor: ICE Publishing
Volume:
5.
Keywords: Water flow; Rocks/rock mechanics; Laboratory equipment
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The effect of differential settlements on the dynamic response of the train-track system: a numerical study
Railway tracks on earthworks with poor geotechnical performance may undergo important differentialsettlements that amplify the dynamic response of the train
Year: 2015
Number Pages:
216
Author(s): Paixão, A.; Fortunato, E.; Calçada, R.
: Engineering Structures
Editor: Elsevier
Volume:
88.
Keywords: Hanging sleepers; Train
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Comunicação
Info
Recycling of construction and demolition waste in geotechnical works
About 50% of the materials extracted from the earth
Year: 2012
Number Pages:
11p.
Author(s): Fortunato, E.; Lopes, M. L.; Curto, P.; Fonseca, A.
Keywords: Portuguese case studies; Geotechnical works; Recycling; Construction and demolition waste
Info
Recycling of construction and demolition waste in geotechnical works
About 50% of the materials extracted from the earth
Year: 2012
Number Pages:
11p.
Author(s): Fortunato, E.; Lopes, M. L.; Curto, P.; Fonseca, A.
Keywords: Portuguese case studies; Geotechnical works; Recycling; Construction and demolition waste
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The Falling Weight Deflectometer: Application to Railway Substructure Evaluation
N/A
Year: 2012
Author(s): Paixão, A.; Fontul, S.; Fortunato, E.
Editor: Civil-Comp Press
Info
Track substructure assessment using non-destructive load tests. A Portuguese case study.
Comfort and safety are crucial aspects in a transport infrastructure project. Depending on axle loads and traffic speeds, parameters are established carefully in order to ensure a good quality in terms of geometry and bearing capacity during the entire infrastructure life cycle, preventing deterioration process. Nevertheless, maintenance actions have to be performed aiming to restore proper track condition. The quality control during the construction is an important factor that can evaluate the performance of materials. Nowadays, the materials are mainly characterised by their physical and mechanical properties, but there is an increased interest in developing performance based specifications that can provide more realistic information about the behaviour of the track during the life cycle. In order to achieve this task, non-destructive tests represent a good solution, as they are cost and time efficient.Among non-destructive loading equipment, one of the most efficient is the Falling Weight Deflectometer (FWD). In this research, FWD tests were undertaken during the construction of a new railway line 29 km long, at the top of the substructure and in different months. Based on the performed load tests, the structural modelling of the track was established through back-calculation, and the variation of the materials moduli for different testing campaigns was evaluated.The main results obtained are presented and analysed in this paper, as well as some considerations regarding FWD testing and interpretation.
Year: 2012
Number Pages:
9p.
Author(s): Chiara, F.; Pereira, D.; Fontul, S.; Fortunato, E.
Editor: Sapienza Università di Roma
Keywords: Structural evaluation; Sub-ballast; Back-calculation; Fwd; Track construction
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A case study in construction optimisation for sub-ballast layer
The performance requirements of modern railway tracks demand a proper design in order to meet safety and passenger comfort standards, taking into account the optimization of the infrastructure life cycle. The sub-ballast layer, namely the characteristics of the materials used, plays a fundamental role in the track behaviour. However the requirements established for these materials are not consensual worldwide. Very stringent requirements have been adopted in many countries, making it difficult to find adequate materials. The studies presented herein were performed during the construction of an upgraded section of the Portuguese Lisbon
Year: 2011
Number Pages:
13pp.
Author(s): Paixão, A.; Fortunato, E.; Fontul, S.
Editor: Engineering Technics Press
Keywords: In-situ testing; Sub-ballast; Construction quality; Design optimisation
Info
Bituminous mixtures application in railway sub-ballast layer
The increasing of loads and traffic speed of the railways requires a better infrastructure, in order to enable the operation in optimal condition and less traffic interruptions due to maintenance actions. At the same time, the natural resources for the material generally used in the sub-ballast layer, namely the granite are limited, taking into account that the requirements in terms of stiffness and wearing resistance are very high.The bituminous mixtures can represent a good alternative to this traditional material. They enable the decreasing of sub-ballast thickness, better impermeability, better behaviour under the lorry traffic during construction and an improvement of the infrastructure stiffness and its continuity along the railway that results in less maintenance works.In this study two different structures are compared, one with granular material and the other one with bituminous material as sub-ballast layers. Falling Weight Deflectometer (FWD) tests were performed in order to establish the structural model. The back-calculation was made using both linear elastic and finite difference method. The results obtained so far are presented in this paper, together with some proposals for future developments.
Year: 2011
Number Pages:
768p-777p.
Author(s): Chiara, F.; Fontul, S.; Paixão, A.; Andrea, A.
Keywords: Structural modelling; Fwd; Sub-ballast; Bituminous mixture
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Estudo da sensibilidade à água de misturas betuminosas
Em Portugal, os valores de referência existentes para a sensibilidade à água de misturas betuminosas foram estabelecidos de acordo com a norma de ensaio militar americana MIL-STD
Year: 2011
Number Pages:
10.
Author(s): Batista, F. A.; Antunes, M. L.; Teixeira, A.; Ferreira, C.; Guimarães, C.; Gomes, V.; Gomes, L.
Keywords: Sensibilidade à água; Misturas betuminosas
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Non destructive tests for railway infrastructure stiffness evaluation
An important part for a proper railway maintenance policy is the evaluation of the condition of an existing railway substructure, in order to detect the deterioration causes. Recently, the use of non destructive techniques for substructure evaluation has increased due to advantages that these monitoring methods present. Several non destructive tests, loading tests and thickness measurement, were performed on a track section, part of a new railway line designed for high speed traffic. This paper presents the results achieved so far, the testing methodologies defined and the main concerns regarding the use of non destructive tests on a railway platform.
Year: 2011
Number Pages:
13p.
Author(s): Fontul, S.; Fortunato, E.; Chiara, F.
Editor: Civil-Comp Press
Keywords: Loading tests; Falling weight deflectometer; Ground penetrating radar; Non destructive tests; Backcalculation; Railway platform
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Rockfill and soil-rock mixtures in road embankments - a case study
The development of transportation infrastructures has led to the need of huge earthmoving volumes, resulting in high embank-ments. In the construction of these embankments, rockfill and soil-rock mixture materials have been used. A 25 km roadway sec-tion, in the North of Portugal, with the difficult topographic conditions, has required the construction of large embankments. The involved formations are essentially granite (South area) and schist and greywacke (North area). To optimize the construction procedure and to evaluate their performance, physical and mechanical characterization of the materials was carried out and mon-itoring equipments were installed in some embankments. For that purpose, five embankments were selected, taking into account, essentially, the geometry and type of material used in their construction. Plate load tests were also performed, aiming at the eval-uation of the deformation modulus of the embankments. In order to measure displacements, vertical and horizontal inclinome-ters, extensometers and pressure cells systems were installed during construction. After construction, topographic marks on the embankment surface were installed. In this paper, the results of the mechanical characterization carried out in situ and in the la-boratory (large triaxial and oedometer tests) are presented. The installed monitoring equipments are also described. The dis-placements during the construction and deformations in service are herein presented.
Year: 2011
Number Pages:
1143-1148.
Author(s): Fortunato, E.; Caldeira, L.
Editor: IOS Press
Keywords: Monitoring; Large triaxial tes; Large oedometer test; High embankments; Soil-rock mixtures; Rockfill
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Sustainable application of construction and demolition
The use of Construction and Demolition Recycled Materials (C&DRM) in road pavementsis envisaged as a solution with environmental and economic benefits. Their application asunbound granular materials in pavement layers (base, sub-base and capping layers) alsohas the advantage to allow the incorporation of large quantities of those materials, fromdifferent origins.The generalised application of C&DRM in road construction is however still limited bysome knowledge gaps, deriving from the lack of information concerning the mechanicaland environmental performance of these materials and from the limited experience withtheir practical application in road construction.A research project, SUPREMA, aiming to contribute to the sustainable implementation ofC&DRM in road pavements, by improving the knowledge concerning the mechanical andenvironmental behaviour of these materials when placed as aggregates in unboundpavement layers, is being developed by the National Laboratory for Civil Engineering(LNEC), in cooperation with Technical University of Lisbon (IST), over three years.This paper discusses the detailed objectives and methodology of the research projectand presents some of its early results, in particular the ones concerning the C&DRMpotential pollution.
Year: 2011
Number Pages:
6 p.
Author(s): Freire, A. C.; Neves, J.; Roque, A. J.; Martins, I. M.; Antunes, M. L.; Ruas Faria, G.
Keywords: Road infrastructures; Demolition and recycled materials; Sustainability
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Books
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Application of a gap-graded asphalt rubber wearing course in the rehabilitation of the pavement of two national road stretches (EN104 and EN105) located in the north of Portugal - Field and laboratory
This case study refers to the first significant experience with asphalt rubber, manufactured by the wetprocess, applied on a full scale rehabilitation project in Portugal. It concerns the application of a gapgradedasphalt rubber wearing course in the rehabilitation of the pavement of National road stretchesEN 104 between Azurara and Trofa and EN 105 between Travagem and Santo Tirso. / O presente caso de estudo refere-se à primeira experiência relevante, em Portugal, na qual seutilizaram misturas com betume modificado com borracha reciclada de pneus na reabilitação deestradas nacionais. Diz respeito, em particular, à aplicação de misturas betuminosas rugosas combetume modificado com borracha em camadas de desgaste, no âmbito da reabilitação do pavimento deum troço da estrada nacional EN 104, entre Azurara e Trofa, e da estrada nacional EN 105, entreTravagem e Santo Tirso.
Year: 2010
Number Pages:
23pp.
Author(s): Batista, F. A.; Antunes, M. L.; Santos, C.
Editor: LNEC
Volume:
NS 122
Keywords: Pt; Laboratory test; National road; Rubber; Recycled materials; Road pavement rehabilitation; Asphalt; In situ test; Asphaltic road pavement
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Application of an open-graded asphalt rubber wearing course in the rehabilitation of the pavement of a stretch of the National Road EN 14 located in the North of Portugal - Field and laboratory case s
This case study refers to a successful application of an asphalt rubber wearing course in the frame ofthe rehabilitation of the pavement of the National Road EN 14 between
Year: 2010
Number Pages:
20pp.
Author(s): Batista, F. A.; Antunes, M. L.
Editor: LNEC
Volume:
NS 123
Keywords: Pt; Laboratory test; In situ test; National road; Rubber; Recycled materials; Road pavement rehabilitation; Asphaltic road pavement; Asphalt
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Application of hot mix asphalt with 20% - 25% reclaimed asphalt in the rehabilitation of the pavement of the motorway A1 between Pombal and Condeixa (Portugal) - Field and laboratory case study
This case study refers to plant hot mix recycling works in the frame of the rehabilitation of a stretch ofthe motorway A1, located in the centre of Portugal.It concerns the use of 20% - 25% of Reclaimed Asphalt in the production of two different asphaltconcrete mixtures for application in binder courses. / O presente caso de estudo refere-se ao fabrico e aplicação de misturas betuminosas recicladas a quenteem central, num troço da auto-estrada A1 localizado no centro do País. Neste caso, foram utilizadas nofabrico de duas misturas diferentes, uma Mistura Betuminosa Densa e um Betão BetuminosoSubjacente à Camada Drenante, respectivamente, cerca de 20 % e 25 % de misturas betuminosasrecuperadas.
Year: 2010
Number Pages:
20pp.
Author(s): Batista, F. A.; Antunes, M. L.
Editor: LNEC
Volume:
NS 119
Keywords: In situ test; Laboratory test; Asphaltic cement road pavement; Recycled materials; Motorway; Road pavement rehabilitation; Hot mix asphalt
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Application of hot mix asphalt with 35% - 40% reclaimed asphalt in the rehabilitation of the pavement of the National road EN 105 between Travagem and Santo Tirso (Portugal) - Field and laboratory cas
This case study refers to the first known application of RAP in the production of hot mix asphaltconcrete in Portugal. It concerns the application of a plant hot mix recycled asphalt concrete as abinder course in a national road stretch located in the North of Portugal. / O presente caso de estudo refere-se à primeira obra realizada em Portugal, na qual se procedeu àreutilização de materiais betuminosos fresados na reabilitação de um pavimento flexível de um trechode uma estrada nacional (EN105), situada no Norte do País. Os materiais fresados foram reciclados emcentral mediante a incorporação de novos materiais, e posteriormente utilizados em camadas deregularização.
Year: 2010
Number Pages:
20pp.
Author(s): Batista, F. A.; Antunes, M. L.
Editor: LNEC
Volume:
NS 118
Keywords: In situ test; Laboratory test; Asphaltic cement road pavement; Recycled materials; National road; Road pavement rehabilitation; Hot mix asphalt
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Cold insitu recycling of the pavement of EN 260 between Serpa and Vila Verde de Ficalho (Portugal) - Field and laboratory case study
This case study refers to an application of cold in situ recycling of an old asphalt pavement usingbitumen emulsion.The rehabilitation works were performed in 2 phases: The first phase consisted in recycling theexisting asphalt and granular layers up to 120 mm deep and application of a slurry surfacing. Thesecond phase consisted in placing an asphalt cold mix binder course and a new slurry surfacing. / O presente caso de estudo refere-se à aplicação de misturas betuminosas recicladas a frio
Year: 2010
Number Pages:
20pp.
Author(s): Antunes, M. L.; Batista, F. A.
Editor: LNEC
Volume:
NS 120
Keywords: Pt; National road; Laboratory test; In situ test; Asphalt binder; Cold mix asphalt; Recycled materials; Road pavement rehabilitation; Asphaltic road pavement; Bitumen emulsion
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Rehabilitation of the IP2 pavement between Barragem do Fratel and EN 118 (Portugal) using cold insitu recycling of existing asphalt layers - Field and laboratory case study
This case study refers to a successful application of cold in situ recycling of asphalt layers from aheavily cracked pavement using bitumen emulsion.A new hot mix asphalt binder course and a new wearing course were placed on the recycled layer. / O presente caso de estudo refere-se a uma aplicação bem sucedida de reciclagem a frio
Year: 2010
Number Pages:
20pp.
Author(s): Antunes, M. L.; Batista, F.A.
Editor: LNEC
Volume:
NS 121
Keywords: Pt; Laboratory test; In situ test; Asphalt binder; Cracked road pavement; Cold mix asphalt; Recycled materials; Road pavement rehabilitation; Asphaltic road pavement; Bitumen emulsion
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Capítulo de Livro
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Case Study of an Inert Steel Aggregate in Road Construction: Characterization and Monitoring of the Structural Behaviour
The use of alternative materials, in particular industrial by-products and waste materials, in the construction oftransport infrastructures and geotechnical works, has been promoted across the world. Nonetheless, considering that, in most situations, the application of some of these materials is fairly recent, little information is available on the long-term performance of the infrastructures in which they were used. This work mentions some characteristics of the Inert Steel Aggregate for Construction (ISAC). It presents some results related to the evolution in the surface characteristics and the structural behaviour of a field trial built on a road section in Portugal. ISAC was used in the embankments and pavement layers. The visual inspection, the results of the mechanical tests performed, and the values of the settlements measured on the surface markings about ten years after the section is open to traffic led to conclude that the pavement in the zone where ISAC was used as a construction material is, in general, in a better condition and presents better structural performance than the adjacent areas built with natural materials. The embankment's maximum settlements in the areas with ISAC were similar to the ones observed in the adjacent areas.
Year: 2023
Number Pages:
5p.
Author(s): Fortunato, E.; Roque, A. J.; Gomes Correia, A.
: Advances in Geoengineering, Geotechnologies, and Geoenvironment for Earth Systems and Sustainable Georesources Management
Editor: Springer
Keywords: Long-term performance; Structural behaviour; Mechanical properties; Inert Steel Aggregate for Construction (ISAC)
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Testing and monitoring in railway tracks
Railway tracks may be perceived as simple physical structures, but in fact they entail a significant level of complexity as refers to the assessment and prediction of their transient and long-term behaviors. These mostly result from the intrinsic characteristics of their components and of the dynamic interaction with the suc-cessive passing trains at different speeds and with different loading characteris-tics. The railway industry
Year: 2022
Number Pages:
229-255.
Author(s): Fortunato, E.; Paixão, A.
: Advances on Testing and Experimentation in Civil Engineering
Editor: Springer
Keywords: Monitoring; Testing, Instrumentation; Railway Tracks
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Modelação numérica avançada do comportamento estrutural de vias-férreas
A via férrea balastrada é uma estrutura relativamente simples, mas exibe um comportamento complexo, nomeadamente devido às distintas solicitações dinâmicas a que está sujeita, e à forma como se comportam e interagem os seus diversos elementos. O método dos elementos finitos é particularmente adequado à análise do funcionamento destas estruturas, possibilitando a modelação das ações e a utilização de modelos constitutivos avançados para os diversos materiais que constituem o sistema, permitindo considerar a variação das características físicas e geométricas no espaço. Neste capítulo descreve-se e demonstra-se a aplicação de uma ferramenta de modelação numérica tridimensional, concebida especificamente para o cálculo da resposta dinâmica da via-férrea, cujo desenvolvimento, ao longo dos últimos anos, tem tido a contribuição dos autores. Para além da apresentação e validação da ferramenta de modelação, são apresentados estudos relativos à análise do comportamento da via em situações particulares.
Year: 2021
Number Pages:
1-32.
Author(s): Fortunato, E.; Paixão, A.; Varandas, J.
: Modelação Matemática em Engenharia de Transportes. A experiência do Departamento de Transportes do LNEC.
Editor: LNEC
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Técnicas de machine learning em sistemas de gestão de pavimentos
A utilização de machine learning tem despertado a curiosidade e o interesse do meio académico e empresarial. Com efeito, a aplicação de machine learning, baseada em técnicas capazes de aprender com os dados, tem sido efetuada com sucesso em diversos contextos. Este sucesso é particularmente evidente nas áreas que utilizam grandes volumes de dados e que procuram obter informação que permita alimentar modelos de previsão.Na área dos Transportes, para além da resolução de questões relacionadas com a mobilidade, é expectável que a aplicação de técnicas de machine learning venha a ser cada vez mais frequente em questões relacionadas com a gestão de infraestruturas, em particular no estabelecimento de modelos de previsão do comportamento.Neste capítulo procura-se evidenciar o potencial da aplicação de machine learning em sistemas de gestão de pavimentos, através da descrição de alguns dos trabalhos desenvolvidos pelos autores neste domínio, essencialmente relacionados com a aplicação de machine learning no desenvolvimento de modelos de previsão do desempenho dos pavimentos, uma das temáticas essenciais dos sistemas de gestão de pavimentos.
Year: 2021
Number Pages:
47-70.
Author(s): Fortunato, E.; Antunes, M. L.; Marcelino, P.
: Modelação Matemática em Engenharia de Transportes. A experiência do Departamento de Transportes do LNEC.
Editor: LNEC
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Análise comparada de um agregado de escória de aciaria como material alternativo para lastro de vias férreas do tipo heavy haul por meio de ensaios triaxiais
Este artigo apresenta uma etapa de uma pesquisa mais abrangente que está em andamento na Universidade do Porto, no âmbito do grupo de pesquisa Construct-Geo, que visa avaliar os aspectos geomecânicos de materiais alternativos para uso como camada de lastro em vias férreas do tipo heavy haul. São apresentados resultados de ensaios triaxiais monotônicos e cíclicos conduzidos em corpos de prova de 150 mm de diâmetro por 300 mm de altura, em escala reduzida numa proporção de 1:2,5 em relação à granulometriade lastro padrão AREMA N. 24. Analisou-se um agregado de escória de aciaria, quimicamente e ambientalmente, inerte comparativamente a um agregado de granito, relativamente à resistência e à deformabilidade. Os ensaios cíclicos foram conduzidos em dois escalões de carga de 500.000 ciclos, sendo cada escalão compatível com o carregamento imposto por vias do tipo heavy haul com, respectivamente,32,5 toneladas/eixo e 40 toneladas/eixo. Os resultados mostraram que o lastro de escória de aciaria apresentou parâmetros de resistência superiores comparativamente ao lastro de granito e um melhor comportamento quanto à deformabilidade, expresso por maiores valores de módulo de resiliência, menoresíndices de quebra e degradação de partículas e uma maior tendência de estabilização das deformações plásticas, fenômeno conhecido como shakedown e que também foi investigado.
Year: 2019
Number Pages:
55-70pp..
Author(s): Delgado, B.; Fonseca, A.; Fortunato, E.; Coelho, D.
: As Engenharias frente a Sociedade, a Economia e o Meio Ambiente 3
Editor: Atena
Volume:
3.
Keywords: Ensaios Triaxiais; Escória de Aciaria; Lastro Ferroviário
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Current state of the use of recycled materials in geotechnical works in Portugal
The reuse of recycled materials in geotechnical works has awakened a growing interest in the last few years in Portugal. A committee (GT-VROG) within the Portuguese Geotechnical Society (SPG) was created recently for analysing the current state of this kind of use and for promoting it nationwide. As part of the activities of the group, a national survey within producers of waste materials and potential users in geotechnical works was carried out, and a national seminar was organised within the framework of the activities of the TC-3 of the ISSMGE, in order to discuss the present situation in the country and the best ways to develop the reuse of this kind of materials in geotechnical applications. The seminar had the participation of representatives of the different entities interested on the subject (producers, users, administration and research centres), as well as of invited foreign specialists from other European countries. Taking advantage of the results of these activities, the current state of the use of recycled materials in geotechnical works in Portugal is briefly presented and analysed next.
Year: 2007
Author(s): Fortunato, E.; Santayana, F.
Editor: Taylor & Francis
Keywords: Geotechnical works; Recycled materials
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Tese de Doutoramento
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A New Approach for the Maintenance Management of Transportation Infrastructures using Machine Learning
Transportation infrastructures are vital to our society. These infrastructures naturally tend to deteriorate over time. A set of activities is then required to manage existing assets in accordance with sound management principles. These activities are usually integrated into systems that manage infrastructures according to technical, social and economic aspects. This research aims to examine the potential of applying machine learning techniques to current transportation infrastructure management systems. Machine learning is an application of artificial intelligence enabling systems to automatically learn and improve from experience (data), arriving at solutions not explicitly programmed. Powered by algorithms that can learn from data, machine learning leads to efficient and effective systems that improve over time. Over the last few years, the application of machine learning has transformed several industries and could do so for transportation infrastructure as well.To achieve the research objectives, a set of studies was performed. Each of these studies had a specific objective, the set of which can be expressed as follows: to define combined performance indicators for pavement condition assessment using machine learning; to develop machine learning models for pavement performance prediction; to formulate machine learning solutions to overcome pavement data issues, such as missing data; to integrate machine learning techniques into decision support systems for pavement maintenance management. Together these studies explored the development of machine learning applications for solving some standard pavement management problems, providing insights into the application of machine learning to transportation infrastructure management systems. The studies successfully demonstrated the potential of machine learning applications for pavement management systems. It showed that machine learning is applicable to various transportation asset management problems, such as condition assessment, performance prediction, and decision support, and that it is able to outperform some of the analytical techniques currently used. Overall, this research work finds that machine learning is a promising tool for transportation infrastructure management systems.
Year: 2020
Author(s): Marcelino, P.
Keywords: Pavement Management Systems.; Decision Support Systems; Prediction Models;; Machine Learning; Transportation Infrastructure Asset Management
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Transition zones in railway tracks: An experimental and numerical study on the structural behaviour
The railway track continually degrades over its life cycle. This has negative consequences for maintenance and availability of the lines and is particularly evident at locations with abrupt changes in the track
Year: 2014
Author(s): Paixão, A.
Keywords: Dynamic train-track interaction; Numerical modelling; Instrumentation and monitoring; Cyclic load triaxial tests; In situ characterisation; Degradation of the track geometric quality; Backfill design and construction; Under sleeper pads; Transition zones; Railway track
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Renovação de plataformas ferroviárias. Estudos relativos à capacidade de carga
Esta dissertação pretende ser um contributo para o desenvolvimento de uma metodologia de abordagem do problema da renovação de plataformas ferroviárias em serviço, em particular no que se refere à avaliação da capacidade de carga e técnicas de reforço. A referida metodologia foi desenvolvida com o objectivo de apoiar os projectos de renovação das vias férreas.Os principais aspectos abordados são os mecanismos que contribuem para a degradação das vias férreas, a caracterização
Year: 2005
Author(s): Fortunato, E.
Keywords: Ensaios in situ; Modelação física; Modelação numérica; Ensaios laboratoriais; Renovação de caminho de ferro; Capacidade de carga; Deformabilidade da via férrea; Fundação da via férrea; Balastro; Linha férrea
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Deformações permanentes de misturas betuminosas em pavimentos rodoviários
Nas últimas décadas tem vindo a verificar-se, em Portugal bem como no resto do mundo, umacentuado crescimento do volume de tráfego rodoviário e das cargas transportadas pelos veículospesados. Tem-se observado, igualmente, um aumento das exigências funcionais, relacionadas com asegurança e conforto do utente das infra-estruturas, a par das preocupações de carácter ambiental, oque conduz à necessidade de pavimentos rodoviários cada vez mais resistentes e duráveis.Consequentemente, tem-se vindo a recorrer a soluções de pavimentação que envolvem maioresespessuras de camadas betuminosas o que implica uma maior parcela de contribuição docomportamento deste tipo de materiais no desempenho das estruturas de pavimentos. Daqui decorre,entre outros aspectos, uma crescente preocupação com a deformação permanente deste tipo demateriais. Esta situação é também sentida em diversos países, nomeadamente nos países europeus,no Canadá e nos Estados Unidos da América.O presente trabalho tem como objectivo contribuir para um melhor conhecimento do comportamentoà deformação permanente de misturas betuminosas aplicadas em camadas de desgaste depavimentos rodoviários, possibilitando o estabelecimento de metodologias e de critérios de avaliação,que conduzam à selecção de materiais adequados às exigências actuais. Como principais aspectosabordados referem-se a caracterização do comportamento viscoelástico destes materiais, através daexecução e interpretação de ensaios laboratoriais com aplicação de cargas repetidas, que simulemas condições observadas in situ, e a modelação do comportamento à deformação permanente dasmisturas.É analisado o fenómeno da deformação permanente, bem como a sua forma de manifestação naestrutura do pavimento
Year: 2002
Author(s): Freire, A. C.
Keywords: Modelação do comportamento estrutrual; Ensaios de simulação em pista de laboratório; Ensaios decompressão uniaxial estático; Ensaio de compressão uniaxial de cargas repetidas; Modelos reológicos; Comportamento viscoelástico; Deformação permanente; Caracterização laboratorial; Misturas betuminosas
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Relatório Científico
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Construção, conservação e reabilitação de estradas de baixo custo - Relatório do curso realizado em Maputo 12 a 16 de Abril de 2010
N/A
Year: 2010
Number Pages:
19pp.
Author(s): Antunes, M. L.; Fortunato, E.
Editor: LNEC
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Estudos relativos a técnicas de conservação e reabilitação de pavimentos - Acção COST 343
N/A
Year: 2010
Number Pages:
14pp.
Author(s): Antunes, M. L.
Editor: LNEC
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Optimization of high-speed railway track using bituminous sub-ballast - Progress report of project PDTC/ECM/70571/2006-2009
N/A
Year: 2010
Number Pages:
36pp.
Author(s): Santos, A. F.; Fontul, S.; Fortunato, E.; Freire, A. C.
Editor: LNEC
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Projecto, construção e reabilitação de pavimentos com misturas betuminosas - Relatório do curso realizado em Cabo Verde de 12 a 15 de Julho de 2010
N/A
Year: 2010
Number Pages:
20pp.
Author(s): Batista, F. A.
Editor: LNEC
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Dismantling of asphalt and recycling road materials in asphalt layers
The interest of recycling of asphalt and other road materials for pavement construction andrehabilitation has been generally growing in Portugal, for the last 15 years. After someoccasional demonstration projects dealing with hot and cold in situ recycling of asphaltlayers, the first significant experiences with cold in situ recycling and hot mix plant recyclingof asphalt applied in full scale rehabilitation projects, took place in the late 1990
Year: 2009
Number Pages:
12p.
Author(s): Antunes, M. L.; Batista, F. A.
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Dismantling techniques and recycling or other end-of-life treatments of other materials not commonly reused in roads
The interest of recycling of waste, industrial by-products and other road materials forpavement construction and rehabilitation has been generally growing in Portugal, for the last10 years.Among the several types of wastes, there
Year: 2009
Number Pages:
22p.
Author(s): Batista, F. A.; Antunes, M. L.; Santos, C.
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Ensaios de comparação interlaboratorial para avaliação da sensibilidade à água de misturas betuminosas compactadas
Este relatório refere-se a um estudo para avaliação da sensibilidade à água de misturasbetuminosas compactadas, aplicando a Norma Europeia EN 12697-12, no âmbito de umprotocolo de cooperação celebrado entre o LNEC e o InIR. Os principais objectivos do estudosão a obtenção de valores de referência para a sensibilidade à água de misturas comcaracterísticas diferentes, a avaliação da reprodutibilidade dos resultados obtidos através daaplicação da norma EN 12697-12 e a elaboração de recomendações relativas ao uso dessanorma.Os trabalhos realizados compreendem a realização de ensaios de comparação interlaboratorialenvolvendo diferentes laboratórios, a análise dos resultados obtidos.Neste relatório descreve-se a metodologia adoptada no estudo, e apresentam-se e discutem-seos resultados obtidos para uma mistura betuminosa drenante, utilizando betume modificadocom polímero.
Year: 2009
Number Pages:
35pp.
Author(s): Baptista, F. A.; Antunes, M. L.
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Caracterização de agregados produzidos em Portugal de acordo com as referências normativas EN 13043 e EN 13242
A obrigatoriedade de aplicação das Normas Europeias de agregados conduziu à necessidade de utilizar novasmetodologias para a caracterização dos agregados a aplicar em misturas betuminosas e em camadas demateriais granulares não ligados ou tratados com cimento, de acordo com o preconizado nas EN 13043 e EN13242, respectivamente.Tendo em vista estudar a aplicabilidade destas metodologias e obter valores de referência para materiaisnaturais frequentemente empregados em obras de pavimentação, foi estabelecido um Protocolo de Cooperaçãoentre a Estradas de Portugal, E.P., S.A1. e o LNEC, no âmbito do qual se realizou um estudo laboratorial paracaracterização de diferentes tipos litológicos de agregados de diferentes qualidades, consideradosrepresentativos dos materiais existentes em Portugal, de acordo com as propriedades consideradas relevantespela Comissão Técnica Portuguesa de Normalização em Agregados
Year: 2008
Number Pages:
152pp.
Author(s): Cacilhas, F.; Jeremias, T.
Keywords: Cimento; Misturas betuminosas; Valores de referência
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Caracterização de agregados reciclados de acordo com o Normativo Europeu prEN933-11
Atendendo à previsível escassez dos recursos naturais, bem como às inequívocas vantagens ambientais da reutilizaçãode materiais que, de outra forma seriam levados a depósito, a aplicação de agregados reciclados na construçãorodoviária tem vindo a suscitar um interesse cada vez maior por parte de diversos intervenientes.No âmbito da actividade do CEN
Year: 2008
Number Pages:
41pp.
Author(s): Freire, A. C.; Antunes, M. L.
Keywords: Pren933-11; Normativo europeu; Agregados reciclados; Caracterização
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Estudo da influência do teor de água dos agregados nos resultados do equivalente de areia
A qualidade dos finos nos agregados é uma das principais características incluídas nos requisitos especificadosnas Normas Europeias harmonizadas de agregados. Existem essencialmente três critérios que permitem avaliara qualidade dos finos: o teor de finos, o valor do equivalente de areia ou o valor do ensaio de azul de metileno.O primeiro critério decorre directamente da análise granulométrica dos agregados. Os restantes critérios, que seaplicam apenas para produtos com teor de finos superior ou igual a 3%, implicam a aplicação de novos métodosde ensaio que, embora sejam similares a métodos anteriormente utilizados em Portugal, têm suscitado algumasdúvidas no meio técnico nacional.Tendo em vista estudar a aplicação dos métodos de ensaio para avaliação da qualidade dos finos, em particularno que se refere à influência do teor de água dos agregados nos resultados do ensaio de equivalente de areia,foi estabelecido um Protocolo de Cooperação entre a Estradas de Portugal, E.P., S.A.1 e o LNEC, no âmbito doqual se realizou um estudo laboratorial enquadrado na actividade da Comissão Técnica Portuguesa deNormalização em Agregados
Year: 2008
Number Pages:
32pp.
Author(s): Freire, A. C.; Antunes, M. L.
Keywords: Equivalente de areia; Agregados; Do teor de água; Estudo da influência
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ICT
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NOVAS SOLUÇÕES DE SUPERSTRUTURA DE VIA PARA A ALTA VELOCIDADE FERROVIÁRIA - Comparação com a via balastrada tradicional
As crescentes exigências impostas ao transporte ferroviário e a necessidade de o tornar num sistemade transporte mais competitivo, têm levado ao desenvolvimento de novas soluções de via-férrea.Estas novas soluções constituem inovações tecnológicas de via-férrea que diferem da via balastradatradicional na utilização de diferentes materiais e métodos construtivos. Apostam fortemente naredução da necessidade de conservação e renovação da via, o que se traduz na diminuição doscustos associados à sua operação, assim como no aumento da disponibilidade da linha.Assim, estas soluções apresentam uma melhor resposta a velocidades de circulação cada vez maiselevadas e a maiores volumes de tráfego, que tendem a conduzir a maior deterioração da via e aconsequentes maiores custos de conservação e renovação. Em comparação com a via tradicional,estas soluções podem ser mais vantajosas, no que se refere à segurança, a aspectos ambientais, àgestão da operação e a custos globais, quando se considera o ciclo de vida da infra-estrutura.Embora estas tecnologias tenham vindo a ser testadas e aplicadas em alguns países, desde há váriasdécadas, em particular no Japão, só mais recentemente diversos países demonstraram especialinteresse pela sua aplicação. Face a estas vantagens, tem-se verificado actualmente uma crescentetendência para a adopção destas novas soluções, sobretudo para as linhas de alta velocidade,particularmente na Europa e Ásia Oriental.Dentro deste contexto, e tendo em conta a previsível integração de Portugal na Rede Europeia de AltaVelocidade, desenvolveu-se o presente estudo com o objectivo de apresentar diversas soluções devia-férrea que estão disponíveis e compará-las com a solução tradicional de via balastrada.O estudo incide na descrição de concepções de via-férrea não tradicionais, como a via sem balastro ea via de apoio misto, fazendo-se especial referência às principais vantagens e desvantagens da viasem balastro, face à solução tradicional de via balastrada, e à experiência da sua aplicação.Apresenta-se ainda uma síntese da situação actual da aplicação destas novas soluções em paísesque apostaram fortemente nas redes de alta velocidade.Do estudo desenvolvido conclui-se que, para novas linhas de alta velocidade, estas soluções podemser bastante atractivas, como alternativa à via balastrada tradicional.Os autores agradecem a todas as entidades e pessoas a título individual a autorização expressa paraa publicação das ilustrações apresentadas neste estudo, encontrando-se estas devidamentereferenciadas.
Year: 2009
Author(s): Paixão, A.; Fortunato, E.
Keywords: Comboios de alta velocidade; Novas tecnologias; Infra-estrutura ferroviária; Via férrea
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Current state of the re-use of waste materials in geotechnical works in Portugal
The reuse of recycled materials in geotechnical works has awakened a growing interest in the last few years in Portugal. A committee (GT-VROG) within the Portuguese Geotechnical Society (SPG) was created recently for analysing the current state of this kind of use and for promoting it nationwide. As part of the activities of the group, a national survey within producers of waste materials and potential users in geotechnical works was carried out, and a national seminar was organised within the framework of the activities of the TC-3 of theISSMGE, in order to discuss the present situation in the country and the best ways to develop the reuse of this kind of materials in geotechnical applications. The seminar had the participation of representatives of the different entities interested on the subject (producers, users, administration and research centres), as well as of invited foreign specialists from other European countries. Taking advantage of the results of these activities, the current state of the use of recycled materials in geotechnical works in Portugal is presented and analysed next.
Year: 2006
Author(s): Fortunato, E.; Santayana, F.; Roque, A. J.
Keywords: Recycled waste materials; Reuse of materials; Geotechnical works
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Outro
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Guia para a reciclagem de misturas betuminosas a quente em central
N/A
Year: 2009
Number Pages:
4pp.
Author(s): DT / NIRA; DG / NGEA; DM / NB
Keywords: Reciclagem de material; Mistura betuminosa a quente
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Guia para a utilização de agregados reciclados em camadas não ligadas de pavimentos
N/A
Year: 2009
Number Pages:
4pp.
Author(s): DT / NIRA; DG / NGEA; DM / NB
Keywords: Reciclagem de material; Pavimento rodoviário; Camada do pavimento; Agregado para estrada
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Guia para a utilização de agregados reciclados grossos em betões de ligantes hidráulicos
N/A
Year: 2009
Number Pages:
8pp.
Author(s): DT / NIRA; DG / NGEA; DM / NB
Keywords: Reciclagem de material; Agregado grosso; Agregado para betão
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Guia para a utilização de materiais reciclados provenientes de resíduos de construção e demolição em aterro e camada de leito de infra-estruturas de transporte
N/A
Year: 2009
Number Pages:
4pp.
Author(s): DT / NIRA; DG / NGEA; DM / NB
Keywords: Aterro; Infra-estrutura de transporte; Reutilização de material de construção; Demolição de obra; Reciclagem de material; Agregado de detrito de obra
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MBR-BMB® MISTURAS BETUMINOSAS PARA PAVIMENTOS RODOVIÁRIOS E AEROPORTUÁRIOS
N/A
Year: 2008
Number Pages:
12pp.
Author(s): D. TRANSPORTES
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