Orientador: Cassio Eduardo Lima de Paiva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T09:00:02Z (GMT). No. of bitstreams: 1 Aguiar_PauloRoberto_M.pdf: 2785267 bytes, checksum: 6bde50559dcc0d0d8052701ee543e1b3 (MD5) Previous issue date: 2007 / Resumo: O estudo desenvolvido neste trabalho consiste na avaliação da capacidade de suporte do subleito ferroviário, através da determinação do risco à ruptura circular da plataforma, de uma secção transversal de um pátio ferroviário sujeito à carga de um veículo estacionado em uma via lateral, são utilizadas as equações. Para fins de desenvolvimento do presente estudo é utilizado o método de Eisenmann para determinação das tensões atuantes na base do trilho. As tensões atuantes na plataforma são calculadas através das equações de Carothers-Terzaghi. A avaliação do risco à ruptura circular é feita através do programa computacional GEOSLOPE-SLOPE/W versão 6. Após a determinação dos fatores de segurança à ruptura para várias situações analisadas, é feita a análise dos resultados obtidos no sentido de determinar as situações de risco de estabilidade da via à ruptura circular da plataforma / Abstract: This study deals with an evaluation of subgrade capacity by determining the circular rupture stability risk of a slope adjacent to a railway yard track subject the tensions of a loaded gondola car parked in this track. The Eisenmann method is applied for determination of tensions at the railway subgrade and the tensions are calculated by means Carothers-Terzaghi equations. The analysis of circular failure risk is made by means of the computer software Geoslope-Slope/W version 6. After calculating the safety factors for many situations, the results are evaluated to stablish the stability risks of the slope adjacent to the railway track / Mestrado / Transportes / Mestre em Engenharia Civil

The railway system is often considered to be an industry where a monopoly occurs “naturally”, which can explain the public ownership and the use of regulations. However, railways in Europe have been subject to reforms during the last three decades. The use of tendering has increased, which is a way of introducing competition for the market in absence of competition within the market. Still, contracting out services previously produced in-house places a heavy burden on the client, where contract design and its incentive structures can be decisive for the outcome of the reform. This dissertation provides empirical evidence on costs and incentives in a publicly owned monopoly that is subject to reforms, namely the provision of railway maintenance in Sweden. Essay 1 estimates the effect of exposing rail infrastructure maintenance to competitive tendering. The results show that this reform reduced maintenance costs in Sweden by around 11 per cent over the period 1999-2011, without any associated fall in the available measures of quality. Essay 2 estimates the relative cost efficiency between and within maintenance regions in Sweden. The results indicate considerable efficiency gaps together with economies of scale not being fully exploited. Essay 3 analyses the effect of incentive structures in railway maintenance contracts. An increase in the power of the incentive scheme reduces the number of infrastructure failures according to the results. In addition, the estimated effect of the performance incentive schemes suggests that more effort towards preventing train delays is made at the expense of preventing other failures. Essay 4 comprises an estimation of marginal costs of rail maintenance. The static model produces slightly lower marginal costs compared to previous estimates on Swedish data. The results from the dynamic model show that an increase in maintenance costs in year t - 1 predicts an increase in maintenance costs in year t. Indeed, there is an intertemporal effect that depends on the performed maintenance activities (governed by the contract design).

In recent decades, railway transport infrastructures have been regaining their importance due to their efficiency and environmentally friendly technologies. This has led to increasing train speeds, higher axle loads and more frequent train usage. These improved service provisions have however brought new challenges to traditional railway track engineering, especially to track geotechnical dynamics. These challenges demanded for a better understanding of the track dynamics. Due to the large cost and available load conditions limitation, experimental investigation is not always the best choice for the dynamic effect study of railway track structure. Comparatively speaking, an accurate mathematical modeling and numerical solution of the dynamic interaction of the track structural components reveals distinct advantage for understanding the response behavior of the track structure. The purpose of this thesis is to study the influence of design parameters on dynamic response of the railway track structure by implementing Finite Element Method (FEM). According to the complexity, different railway track systems have been simulated, including: Beam on discrete support model, Discretely support track including ballast mass model and Rail on sleeper on continuum model. The rail and sleeper have been modeled by Euler-Bernoulli beam element. Spring and dashpot has been used for the simulation of railpads and the connection between the sleeper and ballast ground. Track components have been studied separately and comparisons have been made between different models. The finite element analysis is divided into three categories: eigenvalue analysis, dynamic analysis and general static analysis. The eigenfrequencies and corresponding vibration modes were extracted from all the models. The main part of the finite element modeling involves the steady-state dynamic analysis, in which receptance functions were obtained and used as the criterion for evaluating the dynamic properties of track components. Dynamic explicit analysis has been used for the simulation of a moving load, and the train speed effect has been studied. The displacement of the trackbed has been evaluated and compared to the measurement taken in Sweden in the static analysis.

Tesis por compendio / Real Herráiz, JI. (2015). CONTRIBUTION TO THE MODELIZATION, ANALYTICAL AND NUMERICAL, OF GENERATION AND PROPAGATION OF VIBRATIONS ORIGINATED BY RAILWAY TRAFFIC. ANALYSIS OF MITIGATION PROPOSALS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/52247 / Compendio

La mise en place de trains à grande vitesse a rendu de plus en plus cruciale la compréhension et la prévision du comportement dynamique à long terme des voies ferrées. En particulier, le tassement des infrastructures conditionne le coût de maintenance des voies. Ce tassement d’infrastructure est par ailleurs étroitement lié aux propriétés des matériaux constitutifs sollicités par le chargement cyclique. La thèse décrit les résultats obtenus pour la caractérisation d’un matériau de type « micro-ballast » de constitution semblable à celle d’un ballast utilisé en infrastructure ferroviaire, mais de taille de grain réduite (d/D=6/24). L’expérimentation utilise des appareils triaxiaux de deux diamètres F300mm et F100 mm. 1. Essais sous sollicitation monotone: Les essais poussés jusqu’à rupture ont permis de mettre en évidence une courbure de la courbe intrinsèque sous faible niveau de chargement et un effet d’échelle sensible entre les deux tailles d’échantillon. 2. Essais sous chargement cyclique: Le plan d’expériences a permis de prendre en compte l’influence de la fréquence d’application de la sollicitation cyclique, de la pression de confinement, de la charge appliquée et du nombre de cycles. Les résultats obtenus sont interprétés dans le cadre d’une loi de comportement adaptée à l’étude de sollicitations cycliques à grand nombre de cycles / The use of high-speed trains makes it crucial to understand and predict the long term dynamic behavior of railway tracks. In particular, the settlement of infrastructures incurs track maintenance costs. This settlement of infrastructure is besides closely linked to the physical properties of the material, when stressed by a cyclic loading. The thesis describes the experimental results obtained on a so called « micro-ballast » material whose grain properties are similar to those of a ballast used for train tracks, but having reduced grain size (d/D=6/24) . Experiments are performed by using triaxial testing on tow diameters (300 mm and 100 mm). 1. Tests under monotone compression: failure tests provided evidence for a curvature of the failure envelop and a significant scale effect between both sample sizes. 2. Tests under cyclic loading: The experimental plane took into account the influence of the application frequency used for the cyclic loading, the confining pressure, the applied charge and the number of cycles. An interpretation of the results in the context of constitutive equations which can be used for the simulation of a high number of cycles is presented

Le travail de recherche présenté dans ce document a été réalisé dans le cadre d’une collaboration entre l’ENTPE/ niversité de Lyon et la SNCF. L’objectif de l’étude est la caractérisation des propriétés thermomécaniques des enrobés bitumineux à être utilisés dans la construction de voies ferrées. Le comportement viscoélastique linéaire (VEL) et la résistance à la fatigue d’enrobés pour couche de base couramment utilisés en France ont été étudiés. L’influence de l’eau sur ces propriétés a été aussi étudiée du fait que l’exposition à l’eau des couches bitumineuses en structure ferroviaire peut les altérer et réduire la durée de vie de l’ouvrage. La caractérisation du comportement VEL et de la résistance à la fatigue des matériaux a été faite en réalisant des essais mécaniques en traction-compression sur des éprouvettes cylindriques au laboratoire LTDS/ENTPE. Une nouvelle procédure de conditionnement à l’eau et au gel a été proposée sur la base des méthodes d’essai normalisées française et américaine. La susceptibilité à l’eau des matériaux a été obtenue par comparaison des résultats des essais mécaniques entre éprouvettes conditionnées et non conditionnées. Le comportement VEL des matériaux a été simulé avec le modèle 2S2P1D, développée à l’ENTPE. Trois formules pour couche de base ont été testées : une GB3, une GB4 et une formule appelée GB PMB. Cette dernière est la même formule GB3 mais avec un bitume modifié aux polymères SBS. La GB3 sert comme matériau de référence. La GB4 est un matériau de meilleures performances que la GB3. La formule GB4 étudiée correspond à celle mise en place dans la couche sous-ballast de la Ligne à Grande Vitesse (LGV) Bretagne-Pays de Loire. L’intérêt d’étudier la GB PMB est de savoir si l’utilisation de bitumes modifiés aux polymères est pertinente dans un contexte ferroviaire ou pas. 2 La zone test construite dans la LGV Est-Européenne près de la ville de Reims avec une couche sous-ballast en enrobé bitumineux a servi comme cas d’étude pour cette thèse. Les différents avantages de l’utilisation de matériaux bitumineux en structure ferroviaire retrouvées dans la bibliographie ont été confirmés avec le retour sur l’expérience de cette zone test. Les résultats obtenus des travaux expérimentaux montrent que les trois formules étudiées présentent des capacités portantes (rigidité) suffisantes pour leur utilisation comme couche sous-ballast. La méthode de conditionnement à l’eau et au gel utilisée n’a pas altéré le comportement VEL des matériaux. En ce qui concerne les essais de fatigue, les résultats ont montré que l’utilisation d’un bitume modifié aux polymères augmente sensiblement la résistance à la fatigue de la GB3. La GB PMB a aussi montré une plus faible susceptibilité de la résistance à la fatigue à l’eau et au gel que la GB3. Du fait que les niveaux de sollicitation de la base de la couche d’enrobé de la zone test LVG EE sont très faibles, tous les matériaux étudiés présentent des propriétés satisfaisantes de résistance à la fatigue en couche sous-ballast. / The research presented in this document was carried out in collaboration between the National School of Public Works (Ecole Nationale des Travaux Publics de l’Etat – ENTPE) of the University of Lyon and the French National Railway Company (Société Nationale des Chemins de Fer français – SNCF). The objective of this study is the characterisation of the thermomechanical properties of road base-course bituminous mixtures commonly used in France for their use in railway track structures. Linear Viscoelastic (LVE) and fatigue resistance properties have been investigated. The influence of moisture damage including freeze-thaw cycles on the properties of the studied mixtures was also studied. LVE and fatigue resistance properties were obtained by means of sinusoidal tension-compression tests on cylindrical samples at the ENTPE/LTDS laboratory. A protocol for moisture conditioning of bituminous mixtures samples was developed based on the French and American standard test methods for moisture susceptibility and on the literature review on the subject. Moisture damage was assessed using complex modulus and fatigue tests. The LVE behaviour of the materials was described using the 2S2P1D (2 Springs, 2 Parabolic elements and 1 Dashpot) model developed at the ENTPE/LTDS laboratory. Three road base-course mixtures available in the French market were studied: a GB3, a GB4 and a mixture called GB PMB (for Polymer-Modified Bitumen). The GB3 mixture stands as the reference material since it is commonly used for the base-courses of conventional roads in France. The GB4 mixture stands as a better performing material than the GB3. The specific studied GB4 formulation corresponds to that used as sub-ballast of the Brittany-Loire high-speed line (HSL) in western France. The GB PMB stands as an improved version of the GB3 in which the base bitumen is replaced by polymer-modified bitumen. The interest of the study of this third mixture is to assess the relevance of using PMB’s in bituminous mixtures intended for railway platforms. The test zone of the East-European HSL served as case study to identify the loading conditions and the behaviour of a bituminous sub-ballast layer in a French track. The several advantages of using bituminous mixtures as sub-ballast material identified in the literature are confirmed by the feedback from this test zone. The results obtained show that the studied bituminous mixtures present excellent bearing capacities (stiffness) for their use as sub-ballast layers in France. The used moisture conditioning protocol did not alter the LVE behaviour of the materials. The good performance of the materials is then expected to be perennial regarding the effect of moisture on the LVE behaviour. With respect to fatigue resistance, the results show that the use of a PMB provides an important increase of the fatigue life as well as a reduction of the susceptibility to moisture damage. However, given the identified loading levels of the bituminous sub-ballast in a common French track structure, all three mixtures present adequate fatigue resistance properties.

The aim of this diploma thesis is to elaborate a variant of the technical solution of the Northeast bypass road of the city Hranice and its subsequent comparison with other variant prepared by the company Linio Plan, s.r.o. The main task of the bypass road is the operation of the industrial zone, through which is achieved the relocation of a large part of the transit traffic from the city centre. The basic difference of compared variants is their location to the city, the solution developed by Linio Plan, s.r.o. passes through the industrial zone and the other variant passes outside this zone.

With the introduction of high-speed trains over the past few years, as well as withan increase in traffic loads and volumes, the attractiveness and competitiveness ofthe railway transport system have increased. This leads to the need to develop newcost-effective ways in railway construction, providing an increase in the life cycle ofthe railway track and reducing the need for maintenance.In several European countries, Japan, and the USA, asphalt mixtures, also called“bituminous mixtures”, are used as such an alternative solution in both traditionalballasted and ballastless railway designs. International experience has shown thatbituminous mixtures have good technical characteristics and can meet many of therequirements of modern railway construction, especially when it comes to the useof asphalt materials in ballasted tracks. However, there is a lack of knowledge andexperience in using bituminous mixtures in railway construction in the northernregions and harsh winter conditions.In this thesis, the development of two- and three-dimensional models of ballastedrailway track with an asphalt sub-ballast layer is presented. The analysis of thestatic and dynamic characteristics of the whole model and the asphalt layer exposedto different temperatures is carried out using the finite element method (FEM) inthe COMSOL software. Simulation for all conditions is carried out with a trainspeed of 200 km/h. The relationship between various temperatures from 􀀀30 °Cto +30 °C and the stress-strain behaviour of the asphalt sub-ballast layer is alsodetermined. The results of the study show that both under the influence of lowand high temperatures, the stresses and strains in the asphalt layer are quite small.Besides, the use of asphalt sub-ballast in the track structure reduces deformationsand stresses acting on the subgrade surface.

A via permanente representa um elemento imprescindível na composição do transporte ferroviário e seu desempenho deve ser adequado, de forma a garantir tanto segurança quanto conforto. Assim, diversos aspectos devem ser analisados ainda na fase de projeto, através de dimensionamentos que confrontem diferentes parâmetros da resposta da via e os limites estabelecidos. Dessa forma, o conhecimento do comportamento mecânico da via, devido aos esforços impostos pela passagem do material rodante, passa a ser essencial no projeto de uma estrutura que garanta os requisitos necessários, sem ser inviável economicamente. Visto que esse comportamento mecânico é muito sensível à rigidez vertical da estrutura, o presente trabalho apresenta análises da influência desse parâmetro na resposta da via e, consequentemente, no seu dimensionamento. Nesse contexto, o trabalho abrange tanto o caso de vias em lastro solicitadas por trens de carga, quanto o caso de vias em laje solicitadas por trens de passageiros em meios urbanos. No primeiro caso são realizados estudos paramétricos, por meio de modelos clássicos e um modelo mecanicista, para a análise de momentos fletores e deflexões nos trilhos, bem como tensões verticais nas camadas de lastro, sub-lastro e subleito. Já no segundo caso, são realizados estudos paramétricos relativos à transmissibilidade e à atenuação de vibrações causadoras de ruído secundário. Também é feita uma análise da influência da rigidez vertical na amplificação dinâmica das cargas estáticas, que pode ser aplicada a ambos os casos citados e até extrapolada para casos de vias de alta velocidade. Os resultados mostraram que aumentos de rigidez vertical resultam em ganhos do ponto de vista de momentos fletores e deflexões nos trilhos, além de maior resistência e capacidade de dissipação de tensões verticais nas camadas de lastro, sub-lastro e subleito. Por outro lado, esses aumentos também levaram a maiores tensões nas camadas subjacentes à grade citadas, além de atenuações de vibrações em menores intervalos de frequência e maiores amplificações dinâmicas das cargas estáticas em vias de alta velocidade. Assim, é mostrado que a influência da rigidez vertical, tanto da via como um todo quanto de alguns elementos específicos, não deve ser analisada de forma genérica, pois, dependendo do parâmetro da resposta da via considerado no dimensionamento, seu aumento pode representar uma influência positiva ou negativa. / The railway track is an essential element in the composition of rail transport and its performance should be adequate to ensure both safety and comfort. Therefore, several aspects should be analyzed still in the project phase, through project designs that compare the response of the track from the point of view of different parameters and some stablished limits. Thus, the knowledge of the mechanical behavior of the track due to stresses imposed by the passage of rolling stock becomes essential to the design of a structure which ensures the necessary requirements, without being uneconomic. Since this mechanical behavior is very sensitive to vertical stiffness of the structure, this thesis presents some analyses about the influence of this parameter in the track response and, consequently, in its design. In this context, the research covers both the case of ballasted tracks with freight trains and the case of slab tracks with passenger trains in urban areas. In the first case, parametric studies are performed by means of classical and mechanistic models with analyses of bending moments and deflections in rails, as well as the vertical stresses on ballast, sub-ballast and subgrade layers. In the second, it was analyzed in the parametric studies the transmission and attenuation of vibrations causing ground borne vibration. In addition to these, there is also an analysis of the influence of the vertical stiffness in dynamic amplification of the static loads, which can be applied to both the mentioned cases and even extrapolated to cases of high-speed railways. The results showed that stiffness increases result in positive gains from the point of view of bending moments and deflections in rails, as well as higher strength and dissipation of vertical stresses on ballast, sub-ballast and subgrade layers. On the other hand, this increase of stiffness also lead to higher pressures on the layers cited, in addition to attenuation of vibrations in lower frequency ranges and higher dynamic amplifications of static loads in the case of high-speed operation. Thus, the influence of vertical stiffness should not be analyzed in a generic way, because, depending on the parameter of the track response considered, it can represent a positive or negative influence.

A via permanente representa um elemento imprescindível na composição do transporte ferroviário e seu desempenho deve ser adequado, de forma a garantir tanto segurança quanto conforto. Assim, diversos aspectos devem ser analisados ainda na fase de projeto, através de dimensionamentos que confrontem diferentes parâmetros da resposta da via e os limites estabelecidos. Dessa forma, o conhecimento do comportamento mecânico da via, devido aos esforços impostos pela passagem do material rodante, passa a ser essencial no projeto de uma estrutura que garanta os requisitos necessários, sem ser inviável economicamente. Visto que esse comportamento mecânico é muito sensível à rigidez vertical da estrutura, o presente trabalho apresenta análises da influência desse parâmetro na resposta da via e, consequentemente, no seu dimensionamento. Nesse contexto, o trabalho abrange tanto o caso de vias em lastro solicitadas por trens de carga, quanto o caso de vias em laje solicitadas por trens de passageiros em meios urbanos. No primeiro caso são realizados estudos paramétricos, por meio de modelos clássicos e um modelo mecanicista, para a análise de momentos fletores e deflexões nos trilhos, bem como tensões verticais nas camadas de lastro, sub-lastro e subleito. Já no segundo caso, são realizados estudos paramétricos relativos à transmissibilidade e à atenuação de vibrações causadoras de ruído secundário. Também é feita uma análise da influência da rigidez vertical na amplificação dinâmica das cargas estáticas, que pode ser aplicada a ambos os casos citados e até extrapolada para casos de vias de alta velocidade. Os resultados mostraram que aumentos de rigidez vertical resultam em ganhos do ponto de vista de momentos fletores e deflexões nos trilhos, além de maior resistência e capacidade de dissipação de tensões verticais nas camadas de lastro, sub-lastro e subleito. Por outro lado, esses aumentos também levaram a maiores tensões nas camadas subjacentes à grade citadas, além de atenuações de vibrações em menores intervalos de frequência e maiores amplificações dinâmicas das cargas estáticas em vias de alta velocidade. Assim, é mostrado que a influência da rigidez vertical, tanto da via como um todo quanto de alguns elementos específicos, não deve ser analisada de forma genérica, pois, dependendo do parâmetro da resposta da via considerado no dimensionamento, seu aumento pode representar uma influência positiva ou negativa. / The railway track is an essential element in the composition of rail transport and its performance should be adequate to ensure both safety and comfort. Therefore, several aspects should be analyzed still in the project phase, through project designs that compare the response of the track from the point of view of different parameters and some stablished limits. Thus, the knowledge of the mechanical behavior of the track due to stresses imposed by the passage of rolling stock becomes essential to the design of a structure which ensures the necessary requirements, without being uneconomic. Since this mechanical behavior is very sensitive to vertical stiffness of the structure, this thesis presents some analyses about the influence of this parameter in the track response and, consequently, in its design. In this context, the research covers both the case of ballasted tracks with freight trains and the case of slab tracks with passenger trains in urban areas. In the first case, parametric studies are performed by means of classical and mechanistic models with analyses of bending moments and deflections in rails, as well as the vertical stresses on ballast, sub-ballast and subgrade layers. In the second, it was analyzed in the parametric studies the transmission and attenuation of vibrations causing ground borne vibration. In addition to these, there is also an analysis of the influence of the vertical stiffness in dynamic amplification of the static loads, which can be applied to both the mentioned cases and even extrapolated to cases of high-speed railways. The results showed that stiffness increases result in positive gains from the point of view of bending moments and deflections in rails, as well as higher strength and dissipation of vertical stresses on ballast, sub-ballast and subgrade layers. On the other hand, this increase of stiffness also lead to higher pressures on the layers cited, in addition to attenuation of vibrations in lower frequency ranges and higher dynamic amplifications of static loads in the case of high-speed operation. Thus, the influence of vertical stiffness should not be analyzed in a generic way, because, depending on the parameter of the track response considered, it can represent a positive or negative influence.