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Assessment of automated technologies in Texas for pavement distress identification, texture, and cross slope measurementBurton, Maria Christina 11 September 2014 (has links)
Automated technologies can be beneficial for collecting data on the condition of pavements. As opposed to a traditional manual survey of the road, automated data collection can provide a safer alternative that is objective, repeatable, and consistent, while traveling at highway speeds. Though the automated method is preferred, it still needs to be reliable enough to accurately model the current pavement performance. The Texas Department of Transportation (TxDOT) initiated a project to allow an independent assessment of the accuracy and repeatability of new automated distress data measurements. In this study, 20 550-ft. pavement sections were tested with automated data collection technologies. The sections were located in Austin and Waco Districts. The accuracy and repeatability was evaluated for cracking and other distress measurements, cross slope measurements, and texture measurements. Known manual methods were used as a reference, and a 3D system developed by TxDOT was compared with three systems of other vendors (Dynatest, Fugro, and Waylink-OSU). With the data provided for the texture and cross slope, an additional investigation was done to evaluate hydroplaning potential. This thesis reports in the latter investigation. / text
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Le fauteuil roulant chez le blessé médullaire, facteur déterminant de l'insertion sociale. État des lieux et effets de la locomotion en dévers sur les astreintes physiologiques / Wheelchair in spinal cord injury, determinant factor of social insertion. Status and impact of locomotion on cross slope on physiological strainsPierret, Benoît 03 December 2012 (has links)
Introduction. Les capacités et les possibilités de déplacement en fauteuil roulant manuel (FRM) sont déterminantes pour l'intégration sociale et professionnelle des usagers. Objectifs. Approfondir la connaissance des contraintes de déplacement en FRM à travers 2 études. La 1ère pour identifier les habitudes et préciser les difficultés des usagers ; la 2nde, induite par les résultats de la 1ère, pour évaluer les effets du dévers, encore méconnus, sur les astreintes cardiaques, énergétiques, musculaires et subjectives. Méthodes. La 1ère étude a été menée par questionnaire complété par 118 sujets paraplégiques en FRM. La 2nde étude, en laboratoire avec 25 hommes paraplégiques, comporte 2 tests : un test d?effort sur ergocycle à bras et un test de propulsion de 300 m et 8 conditions combinant 4 dévers (0, 2, 8 et 12 %) et 2 vitesses (0,97 m.s-1 et une vitesse choisie "de confort"). Résultats. La 1ère étude révèle un environnement peu adapté, avec des moyens de transport et des bâtiments souvent inaccessibles sans aide, et des gènes limitant les sorties des usagers parmi lesquelles figure le dévers. La 2nde étude indique des astreintes cardiaques, énergétiques et musculaires significativement modifiées par le dévers et par la vitesse (p < 0,01). L'astreinte subjective n'est pas modifiée par la vitesse. Des différences entre 0 et 2 % sont faibles mais existent. Un dévers de 12 % est difficilement réalisable. Les équilibres des activités musculaires changent dès 2 % de dévers. Le niveau lésionnel modifie de façon très importante les stratégies de déplacements et les niveaux d'astreintes mesurées ou perçues. Discussion-Conclusion. Les effets du dévers sont perceptibles dès 2 % et sont nets et délétères à 8 %. Ce travail permet de proposer de façon plus argumentée un modèle d'astreintes qui conforte le seuil de dévers fixé réglementairement à 2 % permettant à la grande majorité des usagers de FRM de se déplacer de façon autonome et de rester actifs / Introduction. Displacement capacities and possibilities in manual wheelchair (MWC) are strong determinants of social and occupational integration of MWC users. Objectives. Improve the knowledge of the strains involved by displacement in MWC through 2 studies; the first one to identify habits and difficulties of MWC users. The second one, induced by the results of the first one, has assessed the poorly known cardiac, energetic, muscular and subjective strains of the displacement of MWC users on a cross slope. Methods. The first study was a survey answered by 118 paraplegics habitual MWC users. The second one, a laboratory study conducted with 25 paraplegic men, includes 2 tests: a sub maximal arm-cranking test and a 300 m propulsion test with 8 conditions combining 4 cross slopes (0, 2, 8 et 12%) and 2 velocities (0,97 m.s-1 and a "comfortable" chosen one). Results. The first study shows an adverse environment, with many places unreachable without help and disturbances, like cross slope, which hinders users' displacements. The second study demonstrates the increases of cardiac, energetic, muscular and subjective strains with cross slope. Differencies between 0 and 2% cross slopes are low but quantified. Displacement on a 12% cross slope is very difficult. The balance of muscles activities is changing at 2% cross slope. The injury level makes deep changes in the displacements strategies and in as well perceived as measured strain levels. Discussion-Conclusion. Effects of cross slope are perceived for as low as 2% and onwards values. They are high and deleterious at 8%. This work allows to construct a model of cross slope strains which confirms that the regulatory 2% cross slope limit is well chosen because it allows most MWC users to move without help and remain active
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Vägparametrar och deras inverkan på trafiksäkerheten : Fallstudie på länsväg 360 Lycksele - VilhelminaYaqub, Warsame Sami January 2014 (has links)
The interaction between the driver, the car and the road is essential for the road safety. This case study focuses on the road condition and its effect regarding road safety issues. By studying and isolating the road condition aspect and its contributing role to the accident occurrence, the aim is to explore their relationship, as well as highlight the road parameters that are commonly associated with accident occurrence. This result will be used to develop and increase awareness of the impact of poor road alignment and poor road surface conditions on traffic safety, in order to prevent these accidents from occurring. The road parameters chosen for this study include side friction, cross slope and rut bottom cross slope, road texture, curvature, drainage gradient and rutting. The case study was limited to lv 360 in Västerbotten, where all accidents with an unclear cause of the accident were studied, between 2003 and 2012 were carefully studied and assessed based on the condition of the road at the time of the accident. The study was based on accident data from Transportstyrelsens accident database STRADA and road data was obtained from Vecturas Profilograf. Analysis of the various road parameters and their respective safety limits, identified many hazardous sections on lv 360. Low side friction values, insufficient drainage gradient and incorrect cross slopes are some of the shortcomings that were found. The results show that 70% of all accidents occurred on curves where the vehicle either skidded or went off the road. Furthermore, the results show that the side friction demand in 65% of the accidents far exceeded the designed side friction supply according to VGU. Insufficient side friction associated with curves shows an evident relation with the accident occurrence. The analysis shows that 80% of the accidents had deficiencies in two or more road parameters. Improperly designed cross slopes in curves – where the slope instead of resisting the lateral force, contributed to it – was found to create dangerous circumstances for the traffic. These were also found at lv 360, why the cross slope design according to the results, directly affects the accident rate – particularly at curves. Improper cross slope in sections where the gradient is low often result in insufficient drainage gradient, and consequently a high skid risk. These were common on entry and exit points of curves, where the cross slope shifts between straight sections and curves and thus passes zero. The results show that the drainage gradient in 70 % of the accidents was too low and in many cases fell below VGU's requirement of 0.5 % before and after the curve. / Samarbetet mellan föraren, bilen och vägen är essentiellt för trafiksäkerheten. Denna fallstudie fokuserar på vägens tillstånd och dess roll inom trafiksäkerhetsarbetet. Genom att studera och isolera vägaspekten och dess bidragande roll till olycksförekomsten, är målet att tydliggöra relationen mellan dessa, samt belysa de vägparametrar som vanligen associeras med trafikolyckor. Detta för att utveckla och utöka medvetenheten kring effekten av dålig linjeföring och bristfälliga vägytegenskaper, för att i framtiden kunna förebygga dessa olyckor. De parametrar som studerades är bland annat sidofriktionen, tvärfallet och spårbottentvärfallet, texturen, kurvaturen, snedlutningen och spårdjupet. Arbetet avgränsades till länsväg (lv) 360 i Västerbotten, där alla olyckor med en oklar olycksorsak mellan åren 2003 och 2012 studerades, och bedömdes efter vägens tillstånd vid olyckan. Studien baserades på olycksuppgifter från Transportstyrelsens olycksdatabas STRADA och vägmätningar utförda av Vecturas Profilograf. Vid analys av de olika väg parametrarna och deras respektive gränsvärden, identifierades många brister på länsväg 360. Låga sidofriktionsvärden, otillräcklig snedlutningar och felaktiga tvärfall vid kurvor är några av de brister som påhittades. Resultatet visar att 70 % av alla olyckor inträffade i kurvor där fordonet antingen fått sladd eller åkt av vägen. Vidare visar resultatet att sidofriktionsbehovet i 65 % av olyckorna långt översteg den dimensionerande sidofriktionen enligt regelverket Vägar och Gators Utformning (VGU). För liten sidofriktion i samband med kurvor visar en tydlig koppling till olycksförekomsten. Analysen visar dessutom att 80 % av olyckorna hade brister i två eller fler vägparametrar. Felaktigt utformat tvärfall vid kurvor – där lutningen istället för att motverka sidokraften bidrar till den – skapar livsfarliga förutsättningar för trafiken. Även dessa påträffades på länsväg 360, varför tvärfallets utformning enligt resultatet direkt påverkar på olyckstalet, i synnerhet vid kurvor. För litet tvärfall i de sektioner där även längslutningen är låg innebär dessutom otillräcklig snedlutning (resultanten av tvärfallet och längslutningen) och medför stora risker för halka. Dessa är vanliga vid in- och utfarter av kurvor, där tvärfallet övergår mellan raksträcka och kurva och passerar noll. Resultatet visar att 70 % av olyckorna hade för låg snedlutning samt att flera sträckor i många fall underskred VGU:s krav på 0,5 % före och efter kurvan. Som lösning föreslås hastighetssänkning och varningsskyltar vid skarpa kurvor samt att stor kraft bör läggas på korrekt utförda tvärfall som tar hänsyn till sidokraften.
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Studie MÚK silnic R43 s I/43 / Study of R43/ I/43 Grade Separated JunctionLibichová, Jana January 2013 (has links)
Aim of this Master´s thesis is the road adjustment and design of new grade separated junction highway R43 and road I/43,of Černá Hora – Svitávka and to design optimal distribution of transport hubs including the design II/150 and III/37429, which should be connected with existing roads.The adjustment of the routes will be designed in the necessary extent with the optimal distribution of transport hubs regarding the best transport and economical solution and with minimal impact on the enviroment.
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