Papers
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Machine learning approach for pavement performance prediction
In recent years, there has been an increasing interest in the application of machine learning for theprediction of pavement performance. Prediction models are used to predict the future pavementcondition, helping to optimally allocate maintenance and rehabilitation funds. However, few studieshave proposed a systematic approach to the development of machine learning models for pavementperformance prediction. Most of the studies focus on artificial neural networks models that are trainedfor high accuracy, disregarding other suitable machine learning algorithms and neglecting theimportance of models
Year: 2019
Number Pages:
1-14pp.
Author(s): Marcelino, P.; Antunes, M. L.; Fortunato, E.
: International Journal of Pavement Engineering
Editor: Taylor & Francis Online
Keywords: predictive maintenance; international roughness index (IRI); Time series forecasts; Pavement management systems (PMS); Pavement performance models; Machine learning
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Mechanical behavior of inert steel slag ballast for heavy haul rail track: laboratory evaluation
The ballast mechanical behavior is one of most important aspects governing the performance and safety conditionsof railway track lines. Usually comprised of natural crushed rock, the research for alternative ballastmaterials becomes interesting both environmentally and economically. This paper presents a comparison betweenaggregates of steel slag and granite by means of monotonic and cyclic triaxial tests carried out on scaleddown ballast specimens. The monotonic triaxial tests were conducted at three different confining pressures tofailure and to critical state. The long-term cyclic tests (at least 106 cycles) were conducted in two stress pathscompatible with heavy haul loadings. The results showed that the steel slag aggregate has higher values ofstrength parameters compared to the granite aggregate and better long-term deformability behavior, expressedby lower degradation and particle breakage and a faster tendency for stabilization the permanent deformation.
Year: 2019
Number Pages:
1-10pp.
Author(s): Delgado, B.; Fonseca, A.; Fortunato, E.
: Transportation Geotechnics
Editor: Elsevier
Volume:
20.
Keywords: Heavy haul rail track; Triaxial tests; Steel slag ballast; Ballast behavior
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Particle morphology
The ballast railway layer is one of the main applications of crushed rocks in civil engineering. Environmentalconcerns have influenced the use of by-products and recycled materials as alternatives to the exploitation of new quarries. One of the main industrial by-products available near railways is steel furnace slag. Mechanical tests performed by monotonic and cyclic triaxial loading showed that this material can perform better than a granite aggregate traditionally used in the ballast layer. The work presented in this paper intends to be a contribution explaining the influence of the individual particles
Year: 2019
Number Pages:
1-10pp.
Author(s): Delgado, B.; Fonseca, A.; Fortunato, E.
: Environmental Geotechnics
Editor: ICE Publishing
Keywords: Waste management & disposal; Testing & evaluation; Geotechnical engineering
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Smartphone
Railway infrastructure managers run dedicated inspection vehicles to monitor the geometric quality of the track (among other aspects) to detect irregularities and ensure safe running conditions of railway lines, in accordance with specific regulations. Unfortunately, these inspections disturb the normal traffic operation, especially in networks with intense traffic; are generally carried out only a few times per year; and, consequently, do not provide prompt identification of critical situations. Considering the recent developments and cost reduction in sensing capabilities of smartphones, the authors present an approach to use these technologies to perform constant acceleration measurements inside in-service trains to complement the assessment of the structural performance and geometrical degradation of the tracks. Cross-correlation values above 0.85 were obtained between the standard deviations of the longitudinal level and the experimental vertical accelerations measured on-board a passenger train on an 11-km railway stretch. ,e results showed that the approach can be used to identify critical situations that affect the performance of the track, regarding passenger comfort, degradation rates, and risk of derailment. It may comprise a low-cost and crowdsourced complement to the general current practice of track geometric inspection by dedicated vehicles and contribute to an earlier detection of track malfunctions, consequently, to a more efficient maintenance planning and infrastructure management.
Year: 2019
Number Pages:
1-14pp.
Author(s): Paixão, A.; Fortunato, E.; Calçada, R.
: Advances in Civil Engineering
Editor: Hindawi
Volume:
2019.
DOI:
10.1155/2019/1729153
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Comprehensive performance indicators for road pavement condition assessment
The selection and use of technical parameters and performance indicators plays an essential role in thepavement management process. It is known that if more parameters are used, a more accurate evaluationof pavement condition is achieved, improving the choice of maintenance and rehabilitation interventions.However, one of the most expensive activities of the pavement management process is data collection.Accordingly, it is necessary to find a balance between the data collected and the real needs of the process.This paper presents a new approach for the development of pavement condition indicators using a machinelearning algorithm named regularised regression with lasso. The present discussion is supported by a casestudy, which compares the proposed method with current practice for the description of the condition of aPortuguese motorway. The results suggest that the application of machine learning methods can improvethe accuracy of pavement condition indicators when less data are available, contributing to achieve abalance between the needed data and information obtained.
Year: 2018
Number Pages:
1433-1445pp..
Author(s): Marcelino, P.; Antunes, M. L.; Fortunato, E.
: Structure and Infrastructure Engineering
Editor: Taylor & Francis Online
Volume:
14:11.
Keywords: Performance indicators; Regression analysis; Machine learning algorithms; Statistical models; Highway maintenance; Pavement maintenance
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Numerical simulations to improve the use of under sleeper pads at transition zones to railway bridges
Transition zones to bridges and other structures are critical locations in railway tracks that frequently evidencepoor long-term performance. Under sleeper pads (USPs) are reported to reduce ballast degradation and controlthe vertical stiffness of the track, which suggests that USPs can contribute to mitigating the frequent negativeeffects associated with transitions zones. Aiming at understanding in greater depth the influence of USPs on thedynamic behaviour of transition zones and at improving the design of such railway structures, the authors havedeveloped an extensive experimental and numerical study. 3-D FEM models using state-of-the-art numericalapproaches were successfully calibrated and validated using experimental measurements. Simulations supportedprevious findings, highlighting the potential benefit of USPs and pointing to the need to careful designing of theresilient properties of USPs and their arrangement along transition zones, so as to avoid introducing abruptvariations in track vertical stiffness.
Year: 2018
Number Pages:
168-182pp.
Author(s): Paixão, A.; Varandas, J.; Fortunato, E.; Calçada, R.
: Engineering Structures
Editor: Elsevier B.V.
Volume:
164.
Keywords: Train-track interaction; Dynamic analysis; 3-D FEM; Field measurements; Under sleeper pads; Transition zones; Railway track
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Photogrammetry for digital reconstruction of railway ballast particles
Ballast aggregate is a natural material widely used in railway lines. Its mechanical properties and particle geometry are meticulously defined using well-established standards and characterisation procedures. Though extensively validated, these procedures have some limitations: they are operator dependent; only provide major particle dimensions; do not inform on surface colour; nor allow for advanced particle wear analysis or particle-based simulations. This work presents a cost-efficient photogrammetry method for 3D reconstruction of ballast particles, as an alternative to the significantly expensive laser scanning. It produces digital models of equivalent or higher quality, allowing for advanced and automated particle geometry analyses. Particle meshes produced here are shared among researchers.
Year: 2018
Number Pages:
963-976pp.
Author(s): Paixão, A.; Resende, R.; Fortunato, E.
: Construction and Building Materials
Editor: Elsevier B.V.
Volume:
191C.
Keywords: Measurements; 3D reconstruction; 3D digital model; Laser scanning; Physical properties; Particle geometry; Photogrammetry; Aggregate; Railway ballast
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Railway track condition assessment at network level by frequency domain analysis of GPR Data
The railway track system is a crucial infrastructure for the transportation of people and goods in modern societies. With the increase in railway traffic, the availability of the track for monitoring and maintenance purposes is becoming significantly reduced. Therefore, continuous non-destructive monitoring tools for track diagnoses take on even greater importance. In this context, Ground Penetrating Radar (GPR) technique results yield valuable information on track condition, mainly in the identification of the degradation of its physical and mechanical characteristics caused by subsurface malfunctions. Nevertheless, the application of GPR to assess the ballast condition is a challenging task because the material electromagnetic properties are sensitive to both the ballast grading and water content. This work presents a novel approach, fast and practical for surveying and analysing long sections of transport infrastructure, based mainly on expedite frequency domain analysis of the GPR signal. Examples are presented with the identification of track events, ballast interventions and potential locations of malfunctions. The approach, developed to identify changes in the track infrastructure, allows for a user-friendly visualisation of the track condition, even for GPR non-professionals such as railways engineers, and may further be used to correlate with track geometric parameters. It aims to automatically detect sudden variations in the GPR signals, obtained with successive surveys over long stretches of railway lines, thus providing valuable information in asset management activities of infrastructure managers.
Year: 2018
Number Pages:
26p.
Author(s): Fontul, S.; Paixão, A.
: Remote Sensing
Editor: MDPI AG
Volume:
10(4), 559.
Keywords: Network level evaluation; Spectral domain; Railway events; Track geometry; Signal frequency analysis; Railways; Ground Penetrating Radar
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Short soil
The authors present a numerical study on railway track subgrade reinforcement using short soil-binder columns through injection, below the ballast layer. A 3D FEM program developed in MATLAB that considers the dynamic train
Year: 2018
Number Pages:
8-16pp.
Author(s): Francisco, A.; Paixão, A.; Fortunato, E.; Varandas, J.
: Computers and Geotechnics
Editor: Elsevier B.V.
Volume:
98.
Keywords: Train
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A study on the dynamic train-track interaction over cut-fill transitions on buried culverts
Sudden changes in the structural and geotechnical properties of railway tracks along its course are normally associated with subgrade stiffness transitions, differential settlements and, ultimately, hanging sleepers that reduce the performance of the railway system. This paper aims at analysing and quantifying the impact of such situations, particularly cut-fill transitions combined with the presence of culverts, on the train-track system response. A cut-fill transition on a buried culvert is used as case study for which track geometry and stiffness evaluation data were available. A numerical model, considering the coupled train-track interaction, was developed using a 3D FEM dynamic analysis tool that was further improved here with a mixed implicit-explicit time integration scheme. The results suggest that the faster degradation rates typically found at similar locations are mostly related to the development of early permanent deformations in the subgrade layers, rather than to sudden stiffness transitions, which then aggravate the problem by causing important dynamic amplifications in the train-track interaction. Therefore, numerical approaches similar to the one presented herein can be valuable tools for designers and railway infrastructure managers in order to anticipate and mitigate such negative effects at these locations.
Year: 2017
Number Pages:
49
Author(s): Varandas, J.; Paixão, A.; Fortunato, E.
: Computers & Structures
Editor: Elsevier B.V.
Volume:
189.
Keywords: Three-dimensional numerical modelling; Longitudinal level irregularities; Railway track geometric quality; Train-track interaction; Culverts; Railway transition zones
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Comunicação
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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
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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
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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
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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
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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.
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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.
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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
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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
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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
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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.
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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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The way forward for pavement performance indicators across Europe COST Action 354 Performance Indicators for Road Pavements Final Report
The main objective of the COST Action 354
Year: 2008
Number Pages:
72p.
Author(s): Antunes, M. L.; LITZKA, Johann; LEBEN, Bojan; LA TORRE, Francesca; WENINGER-VYCUDIL, Alfred; KOKOT, Darko; Mladenovic, Goran; BRITTAIN, Stuart; VINER, Helen
Keywords: Performance indicators for road pavements
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MISTURAS BETUMINOSAS DE ALTO MÓDULO Aplicação na Beneficiação da EN 14, entre Chantre e Trofa
N/A
Year: 2007
Number Pages:
137pp.
Author(s): Antunes, M. L.
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COST 334 - Effects of wide tyres and dual tvres task group 3 - Pavement wear effects - Mechanistic approach for rutting - Stage 4
N/A
Year: 2000
Author(s): Quaresma, Luis.; Ferreira, P.; Batista, A. L.
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COST 334 - Effects of wide tyres and dual tyres task group 3 - Pavement wear effects - Mechanistic approach for rutting - Stage 2
N/A
Year: 2000
Author(s): Quaresma, Luis.; Ferreira, P.; Freire, A. C.; Batista, A. L.
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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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ABGER 0/31,5 - Agregados britados de granulometria extensa reciclados
N/A
Year: 2023
Author(s): entidade LNEC
Keywords: Documento de aplicação; Reutilização de materiais de construção; Agregados para estradas; Mistura betuminosa; Pavimento rodoviário; Reciclagem de resíduos; Reciclagem de materiais; Agregados de detritos de obras
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Guia para a utilização de misturas betuminosas a frio para a reparação rápida de pavimentos rodoviários
N/A
Year: 2021
Author(s): entidade LNEC
Keywords: Especificação; Pavimento rodoviário; Reparação de pavimento rodoviário; Mistura betuminosa a frio
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Agregado Siderúrgico Inerte para Construção (ASIC) - Utilização em misturas betuminosas do tipo AC20 base
N/A
Year: 2020
Author(s): entidade LNEC
Keywords: Documento de aplicação; Mistura betuminosa; Siderurgia; Pavimento rodoviário; Agregado
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ABGER 0/31,5 - Agregados britados de granulometria extensa reciclados
N/A
Year: 2018
Author(s): entidade LNEC
Keywords: Documento de aplicação; Reutilização de materiais de construção; Agregados para estradas; Mistura betuminosa; Pavimento rodoviário; Reciclagem de resíduos; Reciclagem de materiais; Agregados de detritos de obras
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S&P CARBOPHALT® G - Grelha de fibra de carbono pré-revestida com betume oxidado para reforço de pavimentos
N/A
Year: 2018
Author(s): entidade LNEC
Keywords: Documento de aplicação; Betume; Reforço de pavimento; Fibras de carbono; Grelha; Camada do pavimento; Pavimento de aeroporto; Pavimento rodoviário
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S&P GLASPHALT® G - Grelha de fibra de vidro pré-revestida com betume oxidado para reforço de pavimentos
N/A
Year: 2018
Author(s): entidade LNEC
Keywords: Documento de aplicação; Betume; Fibras de vidro; Grelha; Camada do pavimento; Pavimento de aeroporto; Pavimento rodoviário; Reforço de pavimento
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Guia para a utilização de agregados reciclados provenientes de misturas betuminosas recuperadas para camadas não ligadas de pavimentos rodoviários
N/A
Year: 2016
Author(s): entidade LNEC
Keywords: Especificação; Pavimento rodoviário; Guia; Demolição de obras; Mistura betuminosa; Reciclagem de materiais; Agregados para estradas; Agregados de detritos de obras; Camada do pavimento
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Guia para a utilização de materiais provenientes de resíduos de construção e demolição em caminhos rurais e florestais
N/A
Year: 2016
Author(s): entidade LNEC
Keywords: Especificação; Estrada rural; Guia; Reutilização de materiais de construção; Demolição de obras; Detritos de obras; Reciclagem de materiais; Material de construção de estradas; Estrada florestal
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Guia para a utilização de materiais provenientes de resíduos de construção e demolição em preenchimento de valas
N/A
Year: 2016
Author(s): entidade LNEC
Keywords: Especificação; Valetas; Guia; Reciclagem de materiais; Demolição de obras; Detritos de obras; Reutilização de materiais de construção
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AEIRU - Agregados artificiais de escórias de incineração de resíduos urbanos para pavimentos rodoviários
N/A
Year: 2015
Author(s): entidade LNEC
Keywords: Documento de aplicação; Escória; Agregados para estradas; Resíduo urbano; Incineração de resíduos; Pavimento rodoviário; Reutilização de materiais; Agregados artificiais
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