The Swedish Transport Administration has been giving the task to set up a new standard for concrete slabs for the new high-speed railway in Sweden. They are demanding that the concrete slabs must be dimensioned according to the German Beton Kalender 2000. This report will explore the results when dimensioning a slab track, according to the German Beton Kalender 2000. Moment capacity, deformation, and crack width are calculated according to two structural theories, namely slab and beam theory, and a comparison between the two methods is presented.

According to Swedish guidelines for high speed railways on embankment, the total settlement is limited to 20 mm over a track length of 10 m during the construction service life. The main objective of this thesis was to investigate the deformation in the subgrade (unbound layer) in a slab track, since there are very few studies related to high speed railways on high earth structure, discussing particularly the unbound layer. This thesis examined the unbound layer consisting of granular material by using the discrete element method (DEM) software PFC. There was a focus on the material compaction and deformations due to traffic loading. DEM has the benefit to be able to model deformation with due consideration of processes at microscale level. Two different particle shapes were tested: balls and clumps. The results showed that the settlements were small, possibly associated to the well compacted material and the simplifications in the model, such as the shape of the particles, absence of particle breakage and the applied traffic load. The clump simulations resulted in less settlements and permanent strains compared to the ball simulations. The higher the embankment the more settlements but less strains were produced for all the three simulations. One interesting parameter to study for the balls simulation was the friction between the particles. Increased friction contributed to less settlement. The maximum height of the embankment was limited to around 3,2 m due to time restraints. Simulations for higher embankments are needed to be performed in order to better understand the effect of the embankment height on settlements.

Within the EU's railway research program IN2TRACK3, a product known as the 3MB track system (Moulded Multi Modular Block slab track system) has been developed. The new innovative track system can be explained as a hybrid solution between traditional ballast tracks and slab track systems. The project has a primary objective for the 3MB system to reduce life cycle costs, improve reliability and punctuality, and increase capacity. The modular construction system allows for easier maintenance of railway tracks, as damaged parts can be replaced more quickly. In September 2022, a full-scale test was initiated on a 50-meter stretch in Gransjö, north of Boden, situated along the Iron Ore Line (Malmbana). Initially planned for a 2-year testing period, but the track system was dismantled and removed after approximately one year due to the emergence of a recurring severe crack pattern within the blocks. This degree project aims to conduct a thorough damage investigation, focusing on investigation the reasons behind the repeated crack patterns observed in the 3MB system. The analysis will particularly emphasise the design of the reinforcement and assesses whether the chosen concrete type is suitable for the specific conditions of the construction. Various laboratory tests, including compressive strength, tensile strength, and thin section analysis, are employed in this investigation. Additionally, a comprehensive literature study is conducted to ensure its credibility and quality. The results reveal that the aggregate in the sample is porous. This porosity increases the risk of frost damage and cracking in the concrete. The air content was measured at 7.1%, which is somewhat high, together with a high w/c equivalent between 0.50 and 0.55, which has a potentially negative impact on the strength. The study's in-depth analysis of the 3MB system blocks revealed two main problems: the choice of porous limestone as aggregate and insufficient coverage of the reinforcing steel. The porous nature of limestone led to water absorption and frost susceptibility, while inadequate coverage resulted in corrosion and frost cracking. Laboratory experiments also showed low tensile strength and uneven concrete quality. Calculations indicated the need for spalling reinforcement. Workmanship errors, including haphazard concrete pouring and suboptimal rail fastening solutions, exacerbated the situation. The study highlights the need for improvements in the concrete's waterproofing and fatigue strength to meet the system's requirements and avoid similar problems in the future. Despite the challenges, the project presents potential for success with the right adjustments and lessons learned from the initial testing phase. Despite challenges and identified obstacles in the project, the 3MB system can succeed. By fine-tuning the concrete recipe, and optimizing reinforcement and aggregate quality, the problems can be avoided. It is crucial to look beyond these obstacles and stick to the overall goal of the project: to establish the sustainable and efficient railways of the future. These challenges can be overcome through careful measures and ensure the project's positive contribution to the transport sector. / Inom EU:s järnvägsforskningsprogram IN2TRACK3 har en produkt känt som 3MB spårsystem (Moulded Multi Modular Block slab track system) utvecklats. Det nya innovativa spårsystemet kan förklaras som en hybridlösning mellan traditionella ballastbanor och ballastfria banor. Projektet har som primärt mål för 3MB-systemet att minska livscykelkostnaderna, förbättra tillförlitlighet och punktlighet, och öka kapaciteten. Det modulära byggsystemet möjliggör enklare underhåll av järnvägasspår, eftersom skadade delar kan bytas ut på ett snabbare sätt. I september 2022 inleddes ett fullskaleprov på en 50 meter lång sträcka i Gransjö, norr om Boden, belägen längs Malmbanan. Ursprungligen planerad för en 2-årig testperiod, men spårsystemet demonterades och togs bort efter cirka 1 år på grund av uppkomsten av ett återkommande allvarligt sprickmönster inom blocken. Målet med detta examensarbete är att genomföra en grundlig skadeutredning, med fokus på att undersöka orsakerna bakom de upprepade sprickmönster som observerats i 3MB-systemet. Analysen betonar särskilt dimensioneringen av armeringen och bedömning om den valda betongtypen är lämplig för konstruktionens specifika förutsättningar. Olika laboratorietester, inklusive tryckhållfasthet, draghållfasthet och tunnslipsanalys, används i undersökningen. Dessutom genomförs en omfattande litteraturstudie för att säkerställa studiens trovärdighet och kvalitet. Resultaten avslöjar att ballasten i provet är porös. Denna porositet ökar risken för frostskador och sprickbildning i betongen. Lufthalten uppmättes till 7,1%, Vilket är något högt, och tillsammans med ett högt vatten-cement-tal mellan 0,50 och 0,55, ger de en potentiellt negativ påverkan på hållfastheten. Studiens djupgående analys av 3MB-systemet block avslöjade två huvudproblem: valet av porös kalksten som aggregat och otillräcklig täckning av armeringsstålet. Kalkstenens porösa natur ledde till vattenabsorption och frostkänslighet, medan otillräcklig täckning resulterade i korrosion och frostsprickor. Laboratorieexperiment visade också på låg draghållfasthet och ojämn betongkvalitet. Beräkningar indikerade behovet av spjälkningsarmering. Utförandefel, inklusive ej fullgod betonggjutning och suboptimala rälbefästnings-lösningar, förvärrade situationen. Studien framhåller behovet av förbättringar i betongens vattentäthet och utmattninghållfasthet för att möta systemets krav och undvika liknande problem i framtiden. Trots dessa utmaningar har projektet en potential att bli framgångsrikt med rätt justeringar och lärdomar från den initiala testfasen. Trots utmaningar och identifierade hinder i projektet kan 3MB-systemet lyckas. Genom att finjustera betongreceptet, optimera armeringen och ballastkvaliteten bör uppkomna problemen undvikas. Det är avgörande att se bortom dessa hinder och hålla fast vid projektets övergripande mål: att etablera framtidens hållbara och effektiva järnvägar. Genom noggranna åtgärder kan dessa utmaningar övervinnas och säkerställa projektets positiva bidrag till transportsektorn.

In the last 40 years an increase in train speed and axle load around the world and other challenges in the conventional ballasted track system gave birth to ballastless railway track system. This study examines in depth the various slab track systems that are being used today. Their design characteristics as well as the various requirements for efficient use are thoroughly explained. At least 34 different ballastless systems have been recorded in many railway networks throughout the world. The most significant slab track systems are analysed in detail and compared. Slab track designs have significant advantages comparing to ballasted tracks. The most significant are the high stability of the track, the almost non-existent need for maintenance, the long life cycle (60 years) and the reduced weight and height of the track. Their disadvantages against the ballasted tracks are mainly summarized in their higher construction costs. The Finite Element package ABAQUS/CAE is used to model a 3-D slab track design under static traffic loading. The results suggest that slab tracks have profoundly better stability and durability comparing to ballasted tracks mainly due to their higher stiffness and strength. The author underlines the need for further studies to undoubtedly prove the claimed advantages of slab track systems as well as to improve the costs associated with construction.

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.

Ballastfria spår har på senare tid börjat byggas i allt större utsträckning. En anledning till detta är höjda krav på järnvägstransporter. Ett ballastfritt spår är ofta utformat som en långsträckt betongplatta på mark som för ned lasten från rälerna till underbyggnaden. I nuläget saknar Sverige dimensioneringsprinciper för ballastfria spår. Principerna är redan etablerade i andra länder men behöver inordnas för svenska förhållanden. År 2012 gjorde regeringen bedömningen att en ny stambana för snabbtåg bör byggas. För detta ändamål har Trafikverket utarbetat en ny teknisk systemstandard för höghastighetsbanor. De traditionella ballasterade spåren är inte optimerade för höga hastigheter. Trafikverkets nya systemstandard förutsätter därför att stora delar av den nya stambanan utförs med ballastfritt spår. Syftet med detta examensarbete är att studera dimensionering med hänsyn till det statiska beteendet hos ballastfria spår och skapa en grundläggande förståelse för spårreaktioner. Med hjälp av handberäkningar och datorstödda metoder undersöks elementärfall av belastningar samt sambandet mellan plattans erforderliga böjstyvhet och underbyggnadens styvhet. Handberäkningsmodeller som antas i detta arbete är bland annat Winklerbäddmodellen och diverse vedertagna tvärsnittsmodeller. De datorstödda metoderna som används är FEM-programmet BRIGADE/Plus och BEM-programmet BE-platte. I BRIGADE/Plus används en tvådimensionell modell där marken modelleras som ett elastiskt underlag. I BE-platte används en tredimensionell modell med en markmodell enligt Winklerbäddmodellen. Resultaten från de olika metoderna kontrolleras mot varandra för att verifiera erhållna resultat. Sambandet mellan elasticitetsmodul i plattornas underlag, plattjocklek och lastreaktioner åskådliggörs i diagram samt tvärkraftstabell i kapitel 4. Beräkningsmodellernas beteende diskuteras och jämförs i kapitel 5. / Recently slab tracks have been built more frequently, among other things due to an increasing demand on rail transport. A slab track is often designed as a continuous concrete slab on grade that carries down the load from the rails to the substructure. At present, Sweden lacks design principles for slab tracks. Principles are established in other countries but must be adapted to Swedish conditions. In 2012 the Swedish government made the assessment that a new mainline for high-speed trains should be built. For this purpose, the Swedish Transport Administration prepared a new technical standard for high-speed tracks. Traditional ballasted tracks are not optimized for high speed trains and therefore the new standard requires large parts of the new mainline to be built with slab track. The aim of this thesis is to study the design of slab tracks with respect to their static behavior and create a fundamental understanding of force reactions acting on them. For elementary load cases the relation between required slab bending stiffness and the stiffness of the substructure will be investigated using hand calculations and computer-assisted methods. Models for hand calculation adopted in this work include the Winkler-bed model and various conventional cross-sectional models. The computer-assisted methods used are FEM software BRIGADE/Plus and BEM software BE-Platte. In BRIGADE/Plus the models are two-dimensional and the soil is modeled as an elastic base. In BE-Platte the models are three-dimensional and the soil is modeled according to Winkler-bed model. The results of the various methods are cross-checked against each other to verify the results obtained. The relationship between the modulus of elasticity of the subsoil, plate thickness and load reactions is illustrated in charts and a shear force table in Chapter 4. The behavior of the calculation models is discussed and compared in Chapter 5.

This diploma thesis is focused on operational testing of selected railway lines with different structures of railway superstructure. For the purposes of measuring were chosen suitable measuring sections on the rail corridor and was designed suitable measuring methodology. Dynamic and acoustic parameters of tested structures were determined on the basis of all tests, which were performed. Suitable mathematic method was chosen for evaluation of tests in time and frequency zone. Part of my work is also compare parameters of the tested structures and recommendations for practice.

På Sveriges järnvägsnät bekämpas ogräs med det kemiska bekämpningsmedlet glyfosat. En omställning är nu på gång och fler bekämpningsmetoder behöver introduceras, bland annat för att motverka resistensutveckling hos ogräsen. I detta arbete jämfördes bekämpning med pelargonsyra, hetvatten, vattenånga och elektricitet med avseende på effektivitet, kostnad, energi- och vattenåtgång. Glyfosat användes som referens. Jämförelsen gjordes genom att sammanställa tillgängliga forskningsrapporter. Bekämpningsmetodernas användbarhet analyserades genom att uppskatta resursåtgången för att ersätta den kemiska bekämpningen på linjen eller driftplatser, eller för att bekämpa restriktionsytor. Det undersöktes också huruvida kostnaden för ogräsbekämpning över tid har betydelse för val av ballastfri järnväg. Resultatet visade att de alternativa metoderna är både dyrare och kräver en högre energi- och vattenåtgång än glyfosat. De ger också en mindre effektiv ogräsbekämpning och upprepade behandlingar behöver därför göras under växtsäsongen. Detta i kombination med att de med dagens teknik appliceras i låg hastighet gör bekämpningen dyr och tidskrävande. För att kunna säga i vilken omfattning de alternativa bekämpningsmetoderna är möjliga att implementera behövs riktlinjer för vilken kostnad, effektivitet samt vatten- och energiåtgång som kan tolereras. Resultatet tyder på att det kan vara möjligt att införa alternativa bekämpningsmetoder på driftplatser och restriktionsytor. För att ersätta glyfosat längs hela järnvägslinjen behöver de utvecklas, speciellt med avseende på effektivitet. För bekämpning med hetvatten och vattenånga var den stora vattenåtgången en stor nackdel. Bekämpningsmetodernas kostnad utgjorde under 5 % av det totala underhållsbehovet på en ny järnväg av ballast. Den ökade kostnaden för ogräsbekämpning ledde som mest till att en ballastfri järnväg blev lönsam två år tidigare för de alternativa metoderna än för glyfosat. Valet mellan en ballasterad och ballastfri järnväg bedömdes inte påverkas nämnvärt av detta. Dock identifierades faktorer som kan göra bekämpningskostnaden högre än vad den här rapporten har kunnat påvisa. Vid en omställning från glyfosat till alternativa metoder bör man därför vid lönsamhetsberäkningar för ny järnväg vara vaksam på vad bekämpningen på det ballasterade alternativet skulle kosta. / Weeds are growing along the Swedish railway network. In order for them to not cause problems they are being removed chemically with the herbicide glyphosate. Due to problems such as a risk for an increase in weeds that are tolerant to glyphosate alternative methods for weed control are now being considered.  This report compared pelargonic acid, hot water, hot water steam and electricity as control methods in terms of efficacy, cost, energy and water consumption. Glyphosate was used as a reference. The comparison was made by reviewing available research articles. The usability of the control methods was then analysed by estimating the use of resources necessary to implement each method for three different scenarios. Whether the choice between a ballasted or fixed rail was affected or not by the cost for weed control was also investigated. The results showed that the alternative weed control methods required more energy and water than glyphosate. They also provide less effective weed control which means repeated treatments are necessary during the growing season. This, combined with a low application speed, makes the weed control expensive and time consuming. To be able to say to what extent each control method is possible to implement guidelines are needed for tolerated cost, effectiveness, energy- and water consumption. The result suggests that it is possible to introduce alternative control methods to a certain extent. However, in order to replace glyphosate along the entire main line, the methods all need to be developed, especially in terms of effectiveness. For hot water and steam treatment there is also a need for a decrease in water consumption.  The cost for weed control accounted for less than 5 % of the total cost for maintenance on a new ballasted railway. The rise in cost due to alternative weed management resulted in the fixed track becoming profitable up to two years earlier with the alternative management compared to glyphosate. The choice between a ballasted and fixed track was not considered to be significantly affected by this. However, factors were identified that could make the cost of weed control higher than this report showed. Therefore, when alternative methods are introduced, one should consider the cost for weed control on the ballasted track when making the choice between the two types of tracks.

The master’s thesis deals with the possibilities of railway track modeling. The computational models were created in ANSYS Classic. Simplified 2D model represents a longitudal half of classic single track construction, 3D models represent classic single track construction and RHEDA 2000 slab track. Static and dynamic response of 2D model was compared with analytical solutions by Timoshenko and Fryba. Static and dynamic responses of 3D models were analyzed and compared.