Papers
Info
Evaluating Different Track Sub-Ballast Solutions Considering Traffic Loads and Sustainability
The railway industry is seeking high-performance and sustainable solutions for sub-ballast materials, particularly in light of increasing cargo transport demands and climate events. The meticulous design and construction of track bed geomaterials play a crucial role in ensuring an extended track service life. The global push for sustainability has prompted the evaluation of recycling ballast waste within the railway sector, aiming to mitigate environmental contamination, reduce the consumption of natural resources, and lower costs. This study explores materials for application and compaction using a formation rehabilitation machine equipped with an integrated ballast recycling system designed for heavy haul railways. Two recycled ballast-stabilised soil materials underwent investigation, meeting the necessary grain size distribution for the proper compaction and structural conditions. One utilised a low-bearing-capacity silty sand soil stabilised with recycled ballast fouled waste (RFBW) with iron ore at a 3:7 weight ratio, while the second was stabilised with 3% cement. Laboratory tests were conducted to assess their physical, chemical, and mechanical properties, and a non-linear elastic finite element numerical model was developed to evaluate the potential of these alternative solutions for railway sub-ballast. The findings indicate the significant potential of using soils stabilised with recycled fouled ballast as sub-ballast for heavy haul tracks, underscoring the advantages of adopting sustainable sub-ballast solutions through the reuse of crushed deteriorated ballast material.
Year: 2024
Number Pages:
18p..
Author(s): Castro, G.; Moura, E.; Motta, R.; Bernucci, L.; Paixão, A.; Fortunato, E.; Oliveira, L.; Quispe, J.
: Infrastructures
Editor: MDPI
Volume:
9(3), 54.
Keywords: numerical modelling; ballast waste; recycled ballast
Info
Experimental investigation to analyze the effect of cementation on the geomechanical behavior of steel slag mixtures
The sustainable use of resources requires new strategies to transform industrial byproductsinto raw materials for other applications. This approach, inspired by circular economy funda-mentals, can be successfully applied in transportation infrastructures where a significantamount of natural raw materials is generally required. Slags from the steelmaking processin electric arc furnaces are generally of two types: oxidizing (black colored) and reducing(lighter colored). In Portugal, the oxidizing steel slag or electric arc furnace (EAF) with con-trolled production has been certified as
Year: 2023
Number Pages:
17p..
Author(s): Mica, N.; Rios, S.; Fonseca, A.; Fortunato, E.
: Geotechnical Testing Journal
Editor: ASTM
Volume:
Vol. 47, No. 1.
Keywords: seismic wave velocities; mechanical behavior; cementation; swelling; steel slags
Info
Mechanical behaviour of steel slag-rubber mixtures: Laboratory assessment.
Slags and rubber from end-of-life tires represent a liability to the steel and tire industry, causing economic and environmental problems that are difficult to manage. Transport infrastructures can use these industrial by-products instead of extracting natural raw materials, but the adequate mechanical performance of the materials needs to be assured. This paper addresses the mechanical behaviour of slag
Year: 2023
Number Pages:
20p.
Author(s): Alves, R.; Rios, S.; Fortunato, E.; Fonseca, A.; Delgado, B.
: Sustainability
Editor: MDPI
Volume:
2023, 15, 1563.
DOI:
10.3390/su15021563
Keywords: Physical model; Industrial by-products; Resilient modulus; Triaxial tests; CBR
Info
The use of steel slags in transport infrastructures: a critical review
The increasing demand for the development and expansion of transport infrastructuresrequires alternative solutions that are economically and environmentally viable to providethe necessary raw materials. Transport infrastructures consume a large amount of naturalaggregates; however, from a circular economy perspective, industrial by-products can effec-tively replace these materials. This avoids the environmental impacts associated with the ex-traction of natural raw materials and simultaneously provides a destination for the industrialby-products. For this purpose, it is important to evaluate if existing standards and technicalrequirements that were developed for natural aggregates are suitable for industrial by-prod-ucts. This review study is focused on slags from steelmaking process in electric arc furnaces,which are generally of two types: oxidizing (black colored) and reducing (lighter colored), spe-cifically addressing the requirements of these materials for the granular layers of transportinfrastructures. The chemical composition of the slags is analyzed as well as its physicaland mechanical characteristics, swelling behavior, and leachate content, discussing testing pro-cedures and technical specifications.
Year: 2023
Number Pages:
19p..
Author(s): Mica, N.; Rios, S.; Fonseca, A.; Fortunato, E.
: Geotechnical Testing Journal
Editor: ASTM
Volume:
Vol. 47, No. 1.
Keywords: nonlinear strength envelope; resilient modulus; chemical composition; swelling potential
Info
Close-range photogrammetry for 3D rock joint roughness evaluation
Photogrammetry-based methods using everyday photographic equipment and easily available software have gained relevance for roughness measurement of rock joints, as an alternative to traditional approaches. However, the influence of some aspects, such as the number and orientation of camera poses, the parameters of the Structure-from-Motion, Multi-View Stereo and meshing algorithms, the resolution and accuracy of the reconstructed models, requires proper appraisal. To assess the surface roughness of a granite rock joint specimen using such photogrammetry methods, 3D models generated using different settings (i.e. camera sensors, camera poses, open/free software and workflows) were compared with a reference model obtained by contact digitalization. The results suggest that comparable results can be achieved if the photos adequately cover the specimen and, at least, equivalent vertex densities are attained. Percentiles p5 and p95 of surface deviations of the tested models to the reference mesh were, in general, lower than ±0.1 mm. Estimated roughness parameters showed reduced variability, with a minor impact on the shear strength evaluated according to the Grasselli
Year: 2022
Author(s): Paixão, A.; Muralha, J.; Resende, R.; Fortunato, E.
: Rock Mechanics and Rock Engineering
Editor: Springer
Keywords: Multi-view stereo; Structure-from-motion; Photogrammetry; Roughness; Rock joints
Info
Evaluating environmental effects on the structural behavior of the railroad track subgrade considering different sub-ballast design solutions
The subgrade of a freight railroad track must have sufficient bearing capacity to prevent excessive plastic strains and geometry-related problems to ensure its good performance. The track sub-ballast layer is used to distribute the loads from the ballast to the subgrade, as well as to mitigate climate-based subgrade problems. This study aims to evaluate the effects of Brazilian southeastern tropical climate on subgrade hydraulic and structural behavior, as well as its effect on the railroad track substructure. This is achieved by considering both granular and bituminous sub-ballast solutions. Accordingly, suction sensors were installed at the subgrade for the realtime monitoring and calibration of both track sections. The subgrade water retention was characterized by considering the effect of hydraulic hysteresis. Two independent finite element method (FEM) numerical models were developed. Water flow analyses were performed using a 2-D model to obtain the suction variation in the track substructure profile using climate-track interaction simulations. A 3-D model was used to evaluate the railroad track structural behavior in terms of wheel load
Year: 2022
Number Pages:
100761.
Author(s): Castro, G.; Pires, J.; Motta, R.; Bernucci, L.; Fortunato, E.; Futai, M.
: Transportation Geotechnics
Editor: Elsevier
Volume:
34.
Keywords: Suction; Unsaturated soil; Finite Element Method; Climatic action; Moisture content; Railroad Sub-ballast
Info
Railway track support condition assessment-Initial developments on a vehicle-based monitoring solution through modal analysis
Nowadays, there are multiple initiatives showing a renewed interest on railway transport of goods and passengers around the world. Thus, an efficient management of railway infrastructures, both at the operational level and in terms of economic profitability, is not only desirable but also corresponds to an area of ongoing research. In order to contribute to these efforts, an alternative and novel methodology to evaluate railway track support conditions is presented here, based on modal analysis of the characteristic frequencies of the multi-element system composed by a railway infrastructure and an instrumented vehicle moving over it. This methodology belongs to the group of vibration-based structural damage identification methods, and is focused on observing the characteristic frequencies of this multi-element system, which can be correlated with changes in the physical properties of the railway infrastructure under analysis. An important feature of the proposed methodology is that it should enable the collection of information regarding the conditions of the substructure of a railway infrastructure. By performing this assessment of a railway infrastructure over its length, and over time by comparing different rides over the same railway stretch, important information can be gathered regarding the support conditions of the track. This paper presents a complete description on the current stage of development of the proposed methodology, along with the theoretical model that serves as the basis to interpret the collected data. Preliminary verification of this methodology is performed through the analysis of two case studies regarding the passage of an instrumented vehicle over two underpasses. The results obtained so far show that the proposed methodology can provide relevant information regarding the support conditions of railway tracks.
Year: 2022
Author(s): Morais, J.; Morais, P.; Santos, C.; Paixão, A.; Fortunato, E.
: Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit
Editor: Institution of Mechanical Engineers
Keywords: Signal processing; Vehicle-based inspection; Vibration-based structural damage identification methods; Modal analysis; Track support conditions; Track monitoring
Info
Special Issue
The purpose of this Special Issue was to collect and publish technical and researchpapers, including review papers, focusing on the recycling of road pavement materials topromote pavement sustainability performance. Ten papers were published in total covering the use of construction and demolition waste (reclaimed asphalt pavement, recycledconcrete aggregate and glass) and industrial waste (plastic and slag). The application ofrecycled materials concerns bituminous mixtures, concrete mixtures, and non-traditionalinterlocking blocks or cobbles. The most relevant contributions of each paper are briefly described in the following sections. The papers involved thirty-four authors from eleven countries of Europe (Belgium, Finland, Italy, the Netherlands, and Portugal), Africa (Nigeria),Asia (Malaysia and Saudi Arabia), Australia, and South America (Brazil and Colombia).
Year: 2022
Author(s): Neves, J.; Freire, A. C.
Editor: MDPI
Volume:
Recycling 2022, 7, 12.
Keywords: Editiorial
Info
Uma abordagem de modelação numérica tridimensional do comportamento de longo prazo de vias-férreas considerando a interação dinâmica veículo-via
A complexidade do sistema via-férrea, em termos da variabilidade do comportamento estrutural e material ao longo de seu ciclo de vida, tem-se constituído um obstáculo para o estabelecimento de métodos robustos de previsão do seu comportamento de longo-prazo. Neste trabalho apresenta-se uma implementação computacional que incorpora algumas funcionalidades para uma reprodução mais realista desse comportamento, face a outras existentes. Para demonstrar as potencialidades desta ferramenta, são analisados cenários de plena via, tendo-se introduzido, em alguns deles, uma travessa sem apoio na camada de balastro (
Year: 2022
Author(s): Paixão, A.; Varandas, J.; Fortunato, E.
: Geotecnia
Editor: Sociedade Portuguesa de Geotecnia
Volume:
155.
Keywords: modelação numérica; comportamento resiliente não-linear; deformação permanente; via-férrea
Info
A geotecnia nos pavimentos e vias-férreas e prospetivas para a era digital
O artigo tem como objetivo apresentar as principais contribuições da geotecnia e da era digital nos pavimentos e nas vias-férreas, com importância nas várias fases do ciclo de vida (projeto, construção, operação e manutenção). Neste contexto são apresentados aspetos da caracterização e modelação dos geomateriais e sua influência no desempenho dessas estruturas, através da demonstração de resultados de ensaios de laboratório e
Year: 2021
Number Pages:
113-141.
Author(s): Gomes Correia, A.; Neves, J.; Fortunato, E.
: Geotecnia
Editor: Sociedade Portuguesa de Geotecnia
Volume:
152.
Keywords: digital; pavimentos; Geotecnia nos transportes
|
Comunicação
Info
In situ characterization of an old railway platform with DCP
The elastic stiffness measured in situ is considered a good indicator of the performance of railway platforms. The deformation modulus obtained from the Plate Load Test (PLT) is commonly considered representative of that stiffness. Nevertheless, the PLT is a very expensive and time consuming test. Moreover, it is very difficult to perform when the purpose is to characterize ancient platforms of railway lines that must be maintained active during the renewal works. The Dynamic Cone Penetrometer (DCP) is a much cheaper and simpler test, traditionally used to control the compaction of soils and granular materials. The paper reports the experience of the combined use of PLT and DCP tests for characterizing the platform of the main railway line in Portugal (built in the XIXth century), which has recently been upgraded to high speed passenger trains and freight trains with higher maximum axle load. Correlations between the average resistance to penetration of the DCP and the deformation modulus from PLT are presented for coarse-grained and fine-grained soils. A criterion is proposed for the depth over which the DCP results should be averaged for correlation with the modulus from the PLT.
Year: 2009
Number Pages:
949-952pp.
Author(s): Fortunato, E.; Pinelo, A.; Fernandes, M. M.
Keywords: Deformation modulus; Railway subgrade; Plate load test; Dynamic cone penetrometer
Info
Influência do teor de água na determinação do valor do equivalente de areia
De acordo com a norma europeia EN 933-8:2002
Year: 2009
Number Pages:
10 p.
Author(s): Freire, A. C.; Antunes, M. L.; Reis, S.
Editor: XV CILA
Keywords: Equivalente de areia; Teor de água
Info
Laboratory characterization of different types of aggregates according to European standards
The requirement for application of new European Standards in the field of aggregates led to the need to use new test methods for the laboratory characterization of aggregates for asphalt mixtures and for unbound and cement bound layers, in accordance with EN 13043 and EN 13242, respectively. In order to study the applicability of these methodologies and to obtain reference values for natural aggregates more commonly used in pavement construction, a Research Protocol was established between the Portuguese Road Administration (Estradas de Portugal, EP, SA) and Laboratório Nacional de Engenharia Civil (LNEC). Different types of aggregates of different qualities, considered representative of natural aggregate products used in Portuguese road construction were tested. The test results obtained from the application of the European Standards were compared with the results obtained with the test methods previously used, which are described in National or in ASTM standards. This paper presents the main results obtained in the study.
Year: 2009
Number Pages:
371 - 380.
Author(s): Freire, A. C.; Antunes, M. L.; Reis, S.
Editor: Ezio Santagata
Keywords: Laboratory characterization; Aggregates; European standards
Info
Mechanical characteristics of lime treated soil used on road capping layers in Portugal - Two case studies
The lime treated soils is a well recognized solution for road construction due to its great potential. Nevertheless, it requires preliminary studies to determine the optimal mix formulation and a strict quality control during its application. This paper presents and analyses some results obtained during the mechanical characterization of lime treated road capping layers, performed during the construction of two major highways in Portugal. The load tests performed and the back analysis of their results have allowed an evaluation of the deformation modulus of the lime treated soil layer. The values obtained were significantly higher than those required by the technical specifications applicable to these works. Hence, an optimization of soil lime application might be performed, either by changing the mix formulation based on in situ quality control results or by reducing the pavement thickness according to the deformation modulus measured in situ at the top of the capping layer.
Year: 2009
Author(s): Cruz, J.; Fortunato, E.; Viana da Fonseca, A.
Keywords: Deformation modulus; Load test; Soil treatment; Lime
Info
Metodologia de estudo para a valorização de materiais não tradicionais em infra-estruturas de transporte e obras geotécnicas. O caso das escórias de aciaria da siderurgia nacional: caracterização e mo
A Siderurgia Nacional (SN) estima a produção anual de escórias de aciaria em cerca de 270 000t. A gestão deste importante volume de resíduos constituiu uma fonte de preocupação para a Empresa e para o País. Neste contexto a Fundação para a Ciência e a Tecnologia e a SN apoiam um Projecto de I&D intitulado
Year: 2009
Author(s): Gomes Correia, A.; Ferreira, S.; Roque, A. J.; Fortunato, E.; Cavalheiro, A.
Info
Modelação numérica do reforço de substruturas de Vias Férreas com geossintéticos
Os geossintéticos têm sido aplicados com alguma regularidade em infra-estruturas de transporte, em particular na substrutura da via férrea, cumprindo diversas funções. Em geral, o estabelecimento das características a exigir aos geossintéticos é feito com base em resultados de ensaios de laboratório, de carácter genérico, de observação do comportamento de trechos experimentais e de obras em serviço. No entanto, é importante poder dimensionar a infra-estrutura ferroviária contemplando devidamente a contribuição dos geossintéticos, de acordo com as suas características e com as funções que irão desempenhar, e recorrendo a métodos mecanicistas. Neste trabalho recorre-se à modelação numérica pelo método dos elementos discretos para, através de um estudo paramétrico, analisar o efeito da colocação de uma geogrelha no aumento de rigidez de um maciço estratificado, que pretende representar a substrutura de uma via férrea.
Year: 2009
Author(s): Fortunato, E.; Tavares, P.
Info
Pavement selection stratagies using Life-Cycle cost analysis
Building and maintaining a road network involves the expenditure of large budgets and therefore, designers and decision makers should have the instruments to make the most suitable choice of pavement solution for each particular situation, in order to optimize the investments in road construction and maintenance. The issues involved in life-cycle cost analysis of different paving solutions will vary from region to region, depending on local factors such as environmental conditions and availability of materials and technologies.This paper presents a study that is being carried out in Portugal, concerning the life-cycle cost analysis of different paving alternatives. The analysis is carried out using actual data on construction costs of typical pavement structures in Portugal and taking into consideration appropriate performance models for each type of structure being selected. The models are calibrated using results from long term performance studies and the maintenance strategies considered take into account the current practice in the Portuguese main road network.
Year: 2009
Number Pages:
1229-1238pp.
Author(s): Antunes, M. L.; Marecos, V.; Neves, J.; Morgado, J.
Editor: Enzio Santagata
Keywords: Maintenance; Distress models; Life-cycle; Cost; Pavement
Info
Rigid pavement reinforcement: modelling of structural behaviour
The use of
Year: 2009
Number Pages:
10p.
Author(s): Domingos, P.; Antunes, M. L.; Neves, J.
Keywords: Pavement bearing capacity; Numerical modelling; Structural analysis of pavements; Rigid pavement reinforcement; Airport pavement
Info
Structural Evaluation of Flexible Pavements using Non Destructive Tests
The aim of this paper is to contribute to the improvement of the methodologies used in structural pavement evaluation, concerning in particular the backcalculation of layer moduli based on Falling Weight Deflectometer (FWD) together with Ground Penetrating Radar (GPR) test results and using Artificial Neural Network (ANN) technique for the analysis. A brief description of the test procedures and analysis methods is made.The bearing capacity of a pavement is generally evaluated through non-destructive load testing (NDT). Based on the deflections measured in situ and taking into account the pavement layer thickness and material characteristics a response model of the pavement is established. The layer thicknesses are normally obtained through cores and, if available, GPR measurements. The elastic moduli of the layers are adjusted until the deflections calculated are close to the deflections measured during testing (backcalculation). There are several methods for backcalculation of layer moduli from Falling Weight Deflectometer (FWD) test results. However, the results obtained are not always satisfactory, for several reasons, such as the existence of multiple solutions or errors in the pavement layer thickness. An application of the proposed method, combining FWD and GPR tests, is presented. The analysis of the results showed the suitability and advantages of the proposed methodology for structural pavement evaluation. From the experience gathered some recommendations for use of ANN in pavement structural evaluation were drawn, in view of obtaining reliable results.
Year: 2009
Number Pages:
11p.
Author(s): Fontul, S.
Keywords: Non destructive tests (ndt); Ground penetrating radar (gpr); Falling weight deflectometer (fwd); Pavement evaluation
Info
Valorização das escórias de aciaria em obras geotécnicas
A prevenção da produção de escórias de aciaria (EA) afigura-se não praticável, pelo que, a estratégia de gestão destes resíduos deverá privilegiar as soluções de valorização. A valorização será possível se forem encontrados benefícios económicos, o material satisfizer os valores previstos nas especificações de natureza ambiental e de engenharia, e o seu desempenho em obra for equivalente aos dos materiais naturais. Este trabalho sistematiza a informação técnica-científica, internacional e nacional, na vertente da valorização de EA em obras geotécnicas. Além disso, contempla também aspectos como a durabilidade e a metodologia de análise de sustentabilidade, ponderando os aspectos de natureza ambiental, social e económica. Finalmente estabelece o processo de investigação e desenvolvimento que deve suportar a avaliação do desempenho técnico, económico e ambiental de um estudo de um novo produto para o mercado.
Year: 2009
Author(s): Gomes Correia, A.; Roque, A.; Fortunato, E.; Ferreira, S.; Cavalheiro, A.
|
Books
Info
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
Info
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
Info
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
Info
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
Info
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
Info
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
|
Capítulo de Livro
Info
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)
Info
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
Info
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
Info
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
Info
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
Info
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
|
Tese de Doutoramento
Info
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
Info
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
Info
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
Info
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
|
Relatório Científico
Info
Contributos para o conhecimento das propriedades físicas e mecânicas de materiais de balastro e da sua relevância para o desempenho da via-férrea
No âmbito Programa de Investigação e Inovação do LNEC 2013-2020 (P2I) e inserido no Programa de ID&I do Departamento de Transportes (DT), o Núcleo de Infraestruturas de Transportes tem vindo a desenvolver um projeto de ID&I designado por
Year: 2021
Author(s): Fortunato, E.; Paixão, A.
Keywords: Deformação permanente; Via-férrea; Modelação numérica; Modelação física; Morfologia; Resistência Mecânica; Balastro
Info
CEDR Contractor Report 2016-1. Call 2012: Road owners adapting to Climate Change ROADAPT and CliPDaR projects
Executive SummaryInfrastructure is the backbone of our society. Citizens, companies and governments have come to rely on and expect uninterrupted availability of the road network. Climate change is an important topic within the context of designing, maintaining and operating traffic networks. Most transport infrastructure is intended to be available (in service) to the public for several decades. The life cycles of assets in transport are long enough to take the full strain that comes with climate change; however, climate impact is experienced on a small scale. Crops are destroyed by floods, timber is felled by heavy storms and infrastructure is devastated by various kinds of extreme events. The adaptation of road networks to a changing climate is one of the important issues that road authorities have begun to address and that needs to be further continued in the near future.The main objective of the Conference of European Directors of Roads (CEDR) Call 2012
Year: 2016
Author(s): Fortunato, E.
Keywords: CEDR; CliPDaR; ROADAPT; Climate Change
Info
Establishment of a Road Research Centre in Mozambique_Monthly Progress Report for Phase 2A
The Mozambican Roads Administration (ANE) has embarked on a project to establish a Road Research Centre (RRC) in Mozambique aiming to provide the basis for improving the long-term capacity to undertake relevant, high quality research relating to the road sector of Mozambique. This project forms part of the Africa Community Access Programme (AFCAP), which is a research programme supported by the Department of International Development (DFID) of the Government of the United Kingdom and managed by Crown Agents Ltd on behalf of DFID. CSIR, in association with LNEC has been commissioned by Crown Agents to provide Technical Assistance for phase 2 A of the project, which aims to address institutional issues relating to the RRC, draft a strategic research plan and develop a 5-year business plan for the RRC. This monthly progress report dated January 2014 summarises progress made with the identification of the road research needs of Mozambique; the production of recommendations on the institutional structure of the RRC; the establishment of the Road Research Technical Committee (RRTC) and the Road Research Steering Committee (RRSC); and the drafting of the business and strategic research plans for the RRC. The activities planned for February 2014 are also presented.
Year: 2014
Author(s): Verhaeghe, B.; Paige-Green, P.; Antunes, M. L.; Fortunato, E.
Keywords: Road Research; Mozambique; AFCAP
Info
Ensaios para caracterização laboratorial de misturas betuminosas para pavimentos Rodoviários e Aeroportuários - Relatório do curso realizado em São Tomé e Príncipe de 22 a 25 de outubro de 2012
N/A
Year: 2013
Number Pages:
23pp.
Author(s): Batista, F. A.; Nunes, N.
Editor: LNEC
Info
Establishment of a Road Research Centre in Mozambique. Recommendations on Institutional Structures for the Road Research Centre
The Mozambican Roads Administration (ANE) has embarked on a project to establish a Road ResearchCentre (RRC) in Mozambique aiming to provide the basis for improving the long-term capacity toundertake relevant, high quality research relating to the road sector of Mozambique. This project formspart of the Africa Community Access Programme (AFCAP), which is a research programme supported bythe Department of International Development (DFID) of the Government of the United Kingdom andmanaged by Crown Agents Ltd on behalf of DFID. CSIR, in association with LNEC has been commissionedby Crown Agents to provide Technical Assistance for phase 2 A of the project, which aims to addressinstitutional issues relating to the RRC, draft a strategic research plan and develop a 5-year businessplan for the RRC. In this report, appropriate institutional structures for undertaking research arepresented. It addresses the following: (i) the Terms of Reference for a functioning Road ResearchSteering Committee (RRSC) and Road Research Technical Committee (RRTC), as well as an overview ofthe outcomes of the inaugural meetings of both of these committees; (ii) the institutional location ofthe RRC within the structures of ANE; (iii) the physical location of the RRC in Mozambique; (iv)laboratory support for a functioning RRC; and (v) Staffing of the RRC. All items, with the exception of thelast item (
Year: 2013
Author(s): Verhaeghe, B.; Paige-Green, P.; Antunes, M. L.; Fortunato, E.
Keywords: Mozambique; Road Research Centre
Info
Inspeção, manutenção e reabilitação de pavimentos - Relatório do curso realizado em São Tomé de 21 a 24 de outubro de 2013
No âmbito do Convénio de Cooperação entre o Laboratório Nacional de Engenharia Civil(LNEC) e o Programa de Capacitação dos Laboratórios de Engenharia dos PALOP eAdministração Pública de Timor-Leste 2013, realizou-se no Laboratório de Engenharia Civilde São Tomé e Príncipe (LECSTP) um curso subordinado ao tema
Year: 2013
Number Pages:
32pp.
Author(s): Fontul, S.; Nunes, N.
Editor: LNEC
Keywords: Reabilitação; Manutenção; Inspeção visual; Misturas betuminosas; Avaliação de pavimentos
Info
SUPREMA
N/A
Year: 2013
Number Pages:
87pp.
Author(s): Freire, A. C.; Neves, J.; Roque, A. J.; Martins, I. M.; Antunes, M. L.; Ruas Faria, G.
Editor: LNEC
Info
SUPREMA
N/A
Year: 2012
Number Pages:
70pp.
Author(s): Freire, A. C.; Neves, J.; Roque, A. J.; Martins, I. M.; Antunes, M. L.; Ruas Faria, G.
Editor: LNEC
Info
Camadas de desgaste para a redução do ruído de tráfego - Avaliação do ruído em pavimentos em serviço
N/A
Year: 2011
Number Pages:
39pp.
Author(s): Antunes, M. L.; Coutinho, A. S.; Freitas, E.; Paulo, J.
Editor: LNEC
Info
Suprema
N/A
Year: 2011
Number Pages:
40pp.
Author(s): Freire, A. C.; Neves, J.; Roque, A. J.; Martins, I. M.; Antunes, M. L.; Ruas Faria, G.
Editor: LNEC
|
ICT
Info
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
Info
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
|
Outro
Info
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
Info
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
Info
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
Info
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
Info
MBR-BMB® MISTURAS BETUMINOSAS PARA PAVIMENTOS RODOVIÁRIOS E AEROPORTUÁRIOS
N/A
Year: 2008
Number Pages:
12pp.
Author(s): D. TRANSPORTES
|