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  • 1.
    Fors, Carina
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ihlström, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Symboler i vägbanan: en sammanställning av gällande regelverk i Danmark, Finland, Norge, Sverige, Nederländerna, Storbritannien och Tyskland2012Report (Other academic)
    Abstract [en]

    The aim of this study has been to synthesize existing regulations and guiding principles for use of road marking symbols in the Nordic countries Denmark, Finland, Norway and Sweden, together with the Netherlands, Great Britain and Germany. Additionally, a small literature study has been carried out in order to investigate what documented knowledge the regulations are based upon. Road marking symbols are used in a similar way in the studied countries. However, documented knowledge and research on what the symbols should look like are to a great extent missing. Therefore, it should be possible to standardize the road marking symbols within the Nordic countries, which could lead to a more homogeneous impression where the road users recognize and understand the information, at the same time as the application of the symbols could be simplified.

    In summary, the following road marking symbols could be of interest to standardize within the Nordic countries, regarding use, design and dimensions:

    • Lane arrows
    • Deflection arrows
    • Give way symbols
    • STOP text
    • Speed limit symbols
    • Road numbers
  • 2.
    Fors, Carina
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Johansen, Trond Cato
    Ramböll.
    Lundkvist, Sven-Olof
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Nordic certification system for road marking materials: version 4:20172017Report (Other academic)
    Abstract [en]

    Nordic certification system for road marking materials was introduced in 2015. The system is based on documented performance measurements of material samples applied on test fields on public roads. From 2016, the certification system includes both flat (type I) and structured/profiled (type II) markings. Since 2017 the certification system also includes friction materials (a material with enhanced friction).

    Material tests are carried out at two test sites: one in Norway and one in Denmark. The tests fields are situated on public roads and the tested materials are thus exposed to real traffic conditions and to weather conditions representative for the Nordic countries. The materials are followed up by performance measurements during one or two years. The certification includes requirements on coefficient of retroreflected luminance RL under dry and wet conditions, luminance coefficient under diffuse illumination Qd, friction and colour coordinates. The number of wheel passages is measured at the test sites annually. The certification system includes material identification, which allows for future material sampling and analysis.

    The certification system is based on the European standards EN 1824 Road marking materials – Road trials, EN 1436 Road marking materials – Road marking performance for road users, and EN 12802 Road marking materials – Laboratory methods for identification.

    The report describes the certification system and how it is applied in the Nordic countries. Procedures and methods that are used for application of materials and performance measurements are specified.

  • 3.
    Fors, Carina
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Trafikanters upplevda behov och problem i mörkertrafik i tätort: en fokusgruppsstudie med cyklister, äldre bilförare och äldre fotgängare2010Report (Other academic)
    Abstract [en]

    The aim of this study was to improve knowledge on road users' experiences, problems and needs in night-time traffic in urban areas. Based on a previous literature study, the following road user groups were selected for a focus group study: bicyclists, older drivers and older pedestrians. All three focus groups thought that the problems in night-time traffic in urban areas mainly are related to pedestrians and bicyclists. They seldom have proper lighting and/or retroreflective markings and are thus difficult to detect, not only for drivers but also for other pedestrians and bicyclists. Furthermore, traffic rules for pedestrians and bicyclists are experienced as unclear and inconsistent, which causes irritation and may increase the risk of accidents. Both the bicyclist group and the group with older pedestrians asked for better road markings that clearly show where to walk and where to cycle, since they themselves sometimes find it difficult to know where to walk/cycle and also because they think other pedestrians and bicyclists walk or cycle on the wrong part of the road.

  • 4.
    Johansen, Trond Cato
    et al.
    Ramböll.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Lundkvist, Sven-Olof
    Nordic certification of road marking materials in Denmark 2015–20162016Report (Other academic)
    Abstract [en]

    A Nordic certification system for road marking materials was introduced in 2015. In the first stage, the certification system applies to Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads.

    Today, the certification system includes two test sites: one in Sweden and one in Denmark. However, the present report only deals with the certification in Denmark; the results from the Swedish test site will be presented in another report. The first round of material application took place in 2015, while follow-measurements were carried out around one year later, in 2016. At this point in time, the wheel passage classes P0, P1, P2 and P3 were reached at the Danish test site. In other words, the report presents which materials were certified for the mentioned P classes in 2016.

  • 5.
    Johansen, Trond Cato
    et al.
    Ramböll.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Lundkvist, Sven-Olof
    Nordic certification of road marking materials in Sweden 2015−20162016Report (Other academic)
    Abstract [en]

    A Nordic certification system for road marking materials was introduced in 2015. In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads.

    Today, the certification system includes two test sites: one in Sweden and one in Denmark. However, the present report only deals with the certification in Sweden. The first round of material application took place in 2015, while follow-up measurements were carried out around one year later, in 2016. At this point in time, the wheel passage classes P0, P1, P2, P3 and P4 were reached at the Swedish test site. In other words, the report presents which materials were certified for the mentioned P-classes in 2016.

  • 6.
    Kircher, Katja
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ihlström, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Cyklisters interaktion med extrautrustning, infrastrukturen och andra trafikanter: En semi-kontrollerad fältstudie2017Report (Other academic)
    Abstract [en]

    How cyclists interact with the infrastructure, and how they integrate the handling of additional tasks, is dependent on the surrounding traffic situation and the cyclists’ characteristics. To study these relationships, a semi-controlled field study was conducted with 41 cyclists, who belonged to different cyclist groups with respect to their usual travel speed during transport trips. Speed, gaze direction and tactical behaviour like choice of path and the interaction with incoming text messages was logged, while the cyclists travelled along a six kilometre long route in the inner city of Linköping. Interviews and think aloud protocols, as well as video recordings from different perspectives were employed as well.

    It was common that the cyclists ignored incoming text messages, a third was answered directly while cycling. The texting while cycling did not lead to attentional decrements, because the cyclists adapted their interaction with the telephone to the prevailing traffic situation. The interaction with the phone did not differ substantially between cyclist groups. However, the design of the infrastructure affected the cyclist groups differently, where faster cyclists were delayed more in cases where the infrastructure necessitated stops regardless of the traffic situation, while comfort cyclists were the group delayed most in a roundabout that was difficult to interpret. Cycling on the pavement was common, and it mainly reflects the insecurity experienced in mixed traffic with cars. It is important to consider the different needs of different cyclist types when planning the road infrastructure, to avoid irritation, insecurity and conflicts.

  • 7.
    Koucheki, Behzad
    et al.
    Swedish National Road and Transport Research Institute.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Mobila mätningar av vägmarkeringars retroreflexion i Sverige 2006: en översikt2007Report (Other academic)
    Abstract [sv]

    During the year of 2006 a large number of mobile measurements of road marking retroreflectivity were carried out in Sweden. In total, the retroreflectivity of dry markings was measured on 386 road stretches. Additionally, indirect measurements (predictions) of retroreflectivity of wet road markings were made on 25 road stretches. The measurements had different aims and were not carried out in the same way everywhere, which means that it is difficult to compare results from different regions and, in some cases, even results within the same region. The method for selection of road stretches to be measured and the length of the road stretches have varied between the regions and different kinds of instruments have been used. In three regions also the function of wet road markings has been predicted. All of this means that the results should be interpreted with some caution and that making comparisons between the regions is not meaningful. It is obvious that there is a lot to gain by co-ordinating the function measurements of road markings in the future. Naturally, the regions themselves must decide the extent of the function controls, but when measuring is decided, the strategy for measurement should be managed in such a way that comparisons between counties and regions can be made, and desired issues can be solved. In general, there is a need to consider if the strategy used since the year of 2000 is good.

  • 8.
    Koucheki, Behzad
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Spärrområden i trevägskorsningar med separat körfält för vänstersväng2008Report (Other academic)
    Abstract [sv]

    The aim of the reported project was to make an inventory of existing alternative designs of intersections with a separate left turn lane. From this inventory, estimations of the visibility of the prohibited area and of possible application methods were performed. Finally, a proposal on a well designed prohibited area in such an intersection is shown.

  • 9.
    Koucheki, Behzad
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar år 2006 i VST, VMN och VN2007Report (Other academic)
    Abstract [sv]

    Condition assessments of road marking performance have been carried out in Sweden since the year 2000. Preferably, busy roads (belonging to road marking class 3) have been studied, but lately also road markings on roads with less traffic (belonging to road marking class 2) have been measured. The purpose with the condition assessments has been to answer two questions of importance: - To which degree is the retroreflectivity in the Swedish regulation fulfilled? - How has the performance fluctuated over time? In 2006, measurements were carried out in seven counties, of which five were close to the Stockholm area and two (Västerbotten and Norrbotten counties) in the most northern part of Sweden. This report shows, in detail, the results from the condition assessment 2006 and, also, comprehensive results from assessments during the whole period 2000-2006.

  • 10.
    Koucheki, Behzad
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar år 2007 i VST, VMN och VN2008Report (Other academic)
    Abstract [sv]

    The purpose of the study has, as previously, been to answer two important questions: - To which degree is the retroreflectivity in the Swedish regulations fulfilled? - How has the performance fluctuated over time? In general, it can be stated that the amount of road stretches fulfilling the requirements for dry road marking retroreflectivity is small, only a little more than 50 %. This indicates that the budget for road markings does not reflect the regulation requirements.

  • 11.
    Koucheki, Behzad
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Utvärdering av vägmarkeringar tillhörande klass 2 och 3 i VMN och VST2003Report (Other academic)
    Abstract [sv]

    År 2000 gjordes en landsomfattande tillståndsbeskrivning av vägmarkeringarnas funktion på vägar tillhörande vägmarkeringsklass 3, dvs. på vägar med ÅDT > 4 000 fordon/dygn. Under år 2001 studerades dessutom standarden på vägnätet med mindre trafik, vägar tillhörande vägmarkeringsklass 2, med ÅDT mellan 500 och 4 000 fordon/dygn på uppdrag av Region Mälardalen och Region Stockholm.

    Ovannämnda regioner vill nu veta om vägmarkeringarna på vägar tillhörande vägmarkeringsklass 2 och 3 klarar kraven år 2003 enligt Regler för Underhåll av Vägmarkering (RUV). Man vill också veta hur vägmarkeringarnas standard i respektive region förändrats. Resultaten kan användas för en eventuell omfördelning av medel för vägmarkeringarnas underhåll.

    Den viktigaste parametern gällande vägmarkeringarnas funktion, retroreflexionen, har mätts.Mätningarna gjordes med det mobila mätinstrumentet Ecodyn 30 på vägartillhörande vägmarkeringsklass 2 och 3. Samtliga mätningar gjordes underperioden juli-september 2003 efter det att alla underhållsarbeten var slutförda. 

  • 12.
    Levin, Lena (red.)
    et al.
    Swedish National Road and Transport Research Institute.
    Dukic, Tania
    Swedish National Road and Transport Research Institute.
    Heikkinen, Satu
    Swedish National Road and Transport Research Institute.
    Henriksson, Per
    Swedish National Road and Transport Research Institute.
    Linder, Astrid
    Swedish National Road and Transport Research Institute.
    Mårdh, Selina
    Swedish National Road and Transport Research Institute.
    Nielsen, Benny
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Peters, Björn
    Swedish National Road and Transport Research Institute.
    Äldre i transportsystemet: mobilitet, design och träningsproblematik2007Report (Other academic)
    Abstract [sv]

    Generally, more elderly will be travelling and be out on the roads as active road-users in the future. Research exists on the travelling habits of the elderly; but more in-depth knowledge on the elderly's preferences as license-holders, drivers, road-users and actors in public transport is required. The aim of this report is to give an overview of previous research as well as to indicate a number of directions for future research on the mobility of the elderly as actors within the transport system. The work has a clear multidisciplinary approach, with knowledge from social science, behavioural science and technical research on transport and the elderly. However, the main weight lays on social science and behavioural science issues. The report is divided into eleven chapters: 1) contains a short background, purpose and method questions; 2) discusses the project's scientific and social relevance; 3) provides theoretical background and theoretical concepts; 4) mentions previous research on the elderly as car drivers; 5) is a chapter on license-less vehicles; 6) discusses traffic and road design for the elderly; 7) discusses the elderly as pedestrians and bicycle road-users; 8) is about the elderly in public transport and 9) is about the training of elderly drivers. Chapter 10) consists of a final discussion and chapter 11) summarises point by point the need for research on issues which have come to light in the report

  • 13.
    Linder, Astrid
    et al.
    Swedish National Road and Transport Research Institute.
    Kircher, Albert
    Swedish National Road and Transport Research Institute.
    Vadeby, Anna
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Intelligent Transport Systems (ITS) in passenger cars and methods for assessment of traffic safety impact: a literature review2007Report (Other academic)
    Abstract [en]

    The background for this study is that many Intelligent Transport Systems (ITS) are currently introduced in passenger vehicles aiming at providing increased traffic safety. This provides a need to assess the traffic safety effects from these systems. The question that this report highlights is how these systems are designed and how the effects are evaluated. The review resulted in identification of 300 references of which the most relevant are found in this report. The report contains a description of the background of why and how 20 systems or groups of systems have been developed, in which vehicles they can be found, a short technical description of how they work, publication of traffic safety effects and future development plans. Regarding statistical methods, an overview of how they work and the results when using these methods on ITS are described. In addition, the report contains a summary of ways of assessing safety effects from areas such as food, nuclear power and pharmaceutical industries. The conclusion is that there are currently many different ways of supporting the driver in the task of driving the vehicle. Regarding the impact on traffic safety of these systems it is still an open question which evaluation methods to use.

  • 14.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Engen, Thomas
    SINTEF, Norge.
    Rajamäki, Riikka
    VTT, Finland.
    Helmers, Gabriel
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kantstolpars effekt på trafikantbeteendet2014Report (Other academic)
    Abstract [en]

    In order to improve the visual guidance in night-time traffic most Nordic roads are equipped with delineator posts. The configuration of these posts vary between the countries; as an example the distance between two delineator posts is 100 metres in Denmark, while it is 50 metres in Sweden. The aim of the present study was to investigate which delineator post configuration that gives the best driving behavior. Furthermore, the optimal visibility distance of the retro-reflector of the post was estimated. The results can be used for a harmonization of the Nordic regulations regarding delineator posts. The study was conducted in the VTI and SINTEF driving simulators. The study of configuration (VTI) was validated on the real road in Finland by VTT. In the VTI simulator subjects drove in the dark a loop containing seven different delineator posts configurations, while the study at SINTEF used a loop where the retro-reflectors of the posts had a night-time visibility distance of 100, 200 or 400 metres. In both simulators the speed was registered continuously. The results show that the configuration which today is used in Denmark is to prefer. This configuration gives equal or better driving behavior than other configurations, but to a lower price. The optimal visibility distance of the retro-reflectometer was estimated to 100-200 metres.

  • 15.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fotgängares upptäckbarhet vid olika nivåer på vägbelysningen2011Report (Other academic)
    Abstract [en]

    In Sweden, road lighting is regulated in Vägars och gators utformning (VGU). Generally, the requirement is an average luminance level and a luminance uniformity of the road surface. An important question is if the requirements are reasonable? Too low requirements would mean poor traffic safety and too high levels would mean waste of energy and undesired impact on the environment.

    In night-time traffic, accidents involving vulnerable road users are overrepresented, which may be caused by poor visibility. The aim with the present study was to investigate the influence of the average luminance and the luminance uniformity on the detection distance of pedestrians in road lighting.

    Two pilot studies have been conducted as a full-scale trial on Tagenegatan in Gothenburg. This specific street has a road lighting installation where each light source can be dimmed individually. This means that both the average luminance and the luminance uniformity can be regulated independently. Thus, the effect of the average luminance can be studied at certain levels of uniformity and vice versa. In this experiment the average luminance 1.0, 0.5, 0.35 and 0.0 cd/m2 were studied along with the luminance uniformities 0.0 and 0.4.

    In the first study, five subjects participated, travelling at approximately 50 km/h as passengers in a car. Their only task was to push a silent button when a "pedestrian" was detected. The pedestrian was a grey-painted obstacle, dark grey on one side and light grey on the other and it was located on the right pavement. This meant that the background of the pedestrian partly was the surface of the pavement, partly bushes close behind. The conditions were completely intertwined, which meant that six light conditions were studied, involving four pedestrians; light and dark grey, positioned just behind a light source and between two lanterns, respectively.

  • 16.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Prediktion av vägyteluminans i vägbelysning2008Report (Other academic)
    Abstract [sv]

    In night-time driving, road lighting is important to road safety. Consequently, it is important that the performance of the lighting is satisfactory, not only immediately after installation, but also over time. Therefore, the performance, which in most cases is described by the road surface luminance, should be checked regularly, using condition assessment. Condition assessment of road lighting is preferably carried out using mobile measurement equipment. However, luminance is difficult, or even impossible, to measure at speed. The luminance of a road surface is partly dependent on the illuminance and partly on the reflection properties of the surface. The first parameter should be possible to measure at speed, while the latter might be characterized by the daylight luminance coefficient, which can be measured using a hand-held instrument. This report describes an attempt to predict the luminance of a road surface in road lighting from mobile measurement of illuminance and hand-held measurement of the luminance coefficient in few measurement points on the surface. The luminance can then be estimated as the product of these two parameters.

  • 17.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Upptäckbarhet av fotgängare i mörker vid övergångsställen2007Report (Other academic)
    Abstract [sv]

    Efter att den så kallade zebralagen infördes år 2000 har olyckorna vid övergångställen ökat, både påkörning av fotgängare och upphinnandeolyckor. Detta skulle delvis kunna förklaras av att bilisterna alltför sent upptäcker fotgängare som står i begrepp att korsa gatan, vilket kan vara speciellt uttalat i mörkertrafik. För att minska riskerna vid övergångsställen har Vägverket och kommuner vidtagit åtgärder, vilka oftast har inneburit intensivbelysning och/eller insnävning av körfälten. Denna studie redovisar och utvärderar några sådana åtgärder. Resultaten visar att intensivbelysning inte alla gånger är tillräckligt för att förbättra upptäckbarheten av fotgängare; en mörkt klädd fotgängare som går över bakom övergångsstället kan till och med ha sämre upptäckbarhet än om övergångsstället inte skulle ha haft intensivbelysningen. Om däremot den extra belysningen kompletteras med en insnävning av körfältet förbättras upptäckbarheten, oavsett om fotgängaren har ljusa eller mörka kläder eller om denne går över vid eller bakom övergångsstället. För att förbättra upptäckbarheten av fotgängare vid övergångsställe i mörker, rekommenderas med stöd av resultaten, att övergångsstället intensivbelyses och att körfälten in mot detsamma snävas in. En mörkklädd fotgängare, som passerar övergångsstället bakom detta har dålig upptäckbarhet om övergångsstället är intensivbelyst, men ej insnävat.

  • 18.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Vägbelysningens betydelse för fotgängares synbarhet i mörker2012Report (Other academic)
    Abstract [en]

    The visibility of pedestrians has been measured in a full-scale field experiment. The visibility was quantified by the detection distance to pedestrian who is about to cross a street. Six subjects, sitting as passengers in a Volvo, were used for registering the detection distances. Two pedestrians were standing on the pavement along a street and the subject’s only task was to push a button when they could detect a pedestrian. The test site was located in an industrial area with no or little traffic, and consequently, the measurements could be accomplished without any disturbance from oncoming vehicles. Four illumination conditions were used: 100 % or 65 % of full effect on every light source, 100 % on every second light source, the others switched off, and finally no road lighting at all. In these lighting conditions the average luminance of the road surface turned out to be 1.0; 0.5 and 0.0 cd/m2 with the luminance uniformity 0.4. Furthermore, the luminance uniformity was 0.4 and 0.0 at the average luminance 0.5 cd/m2. The clothing of the pedestrian was either light-grey or black. The pedestrian’s position along the road was either 5 metres behind a light source or half-way between two light sources. Every subject registered every condition two or four times. The independent variables were lighting condition, clothing and position along the road. The only dependent variable was the detection distance.

  • 19.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute.
    Sörensen, Kai
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Nordiskt samarbetsprojekt inom NMF: synbarhet av VMS2006Report (Other academic)
    Abstract [sv]

    In recent years, VMS (Variable Message Signs) have been used more frequently in Nordic countries. The VMS should fulfil the requirements given in the standard EN 12966-1, with respect to symbol luminance, luminance contrast, colour and beam width. This study has primarily investigated which symbol luminances are suitable from the road-user's point of view, i.e. luminances which make the sign conspicuous, but not as high as to involve glare and thereby impair legibility. In fact, the study includes three observation occasions, At the third occasion, comparative observations of two variable message signs with white symbols placed next to each other were made. The report mainly deals with this latter observation study. At the assessments, three observers (the authors) had to decide which symbol luminance they found "most suitable". This implied that the three observers compared the two signs, which always had different luminance, with respect to "suitable symbol luminance" and through a series of comparisons the preferred luminance was defined. This was done through observations at a distance of 46 metres from the signs during various light conditions, in daylight, dawn and darkness. The results show that to obtain the luminances that were considered "most suitable", the VMS had to belong to luminance class L3. If the correlation in the standard between luminance and illuminance would be based on this "suitability measure", this result would be true for all lighting conditions. However, there was a tendency that in darkness, it was also possible for a sign belonging to class L2 to fulfil the demand for symbol luminance. Daylight conditions became standardizing, though, and under these lighting conditions luminances in class L3 were preferred. A comparison of the results from the three observation occasions shows great concordance: A predominant amount of observations show that luminance class L3 is demanded for achieving "suitable" luminance. However, there are also indications that luminances belonging to class L2 could be accepted, but from the road-user's point of view, L3 is still preferred.

  • 20.
    Lundkvist, Sven-Olof
    et al.
    Swedish National Road and Transport Research Institute.
    Wiklund, Mats
    Swedish National Road and Transport Research Institute.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Fotgängares upptäckbarhet i mörker vid övergångsställen2004Report (Other academic)
    Abstract [sv]

    En metod för studium av fotgängares upptäckbarhet vid övergångsställen i mörker på gator med stationär belysning har testats. Metoden innebär att från svart/vita foton gör försökspersoner jämförande bedömningar av upptäckbarheten vid ett antal par av övergångsställen. Från dessa observationer beräknas oddset för att ett övergångsställe bedöms ge bättre upptäckbarhet än ett annat. Datainsamlingsmetoden visade sig fungera tillfredsställande men bör modifieras något. Bland annat ska bakgrundsvariabler som beskriver vägytans ljushet mätas fysikaliskt, t.ex. belysningsstyrkan mot vägytan och ytans reflexionsegenskaper. Analysmetoden fungerar, även om den kan anses vara något ovanlig och komplicerad. Traditionella metoder, såsom variansanalys och liknande, kan inte användas på grund av att observationerna inte är oberoende. I stället måste data analyseras med en s.k. logoddsmetod. Resultaten från denna metodstudie visar att inte endast beläggningsytans luminans är avgörande för upptäckbarheten, utan även övergångsställets utformning. Således visade det sig att en insnävning av övergångsstället, så att fotgängaren väntar i förarens siktlinje, ger goda möjligheter för upptäckt. Även ett övergångsställe på gata med ljus gatsten, men utan insnävning, innebar god upptäckt av fotgängaren. Ett ytterligare resultat är att separatbelysning av övergångsstället fungerar dåligt om fotgängaren passerar bakom övergångsstället.

  • 21.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Alternativa typer av utmärkning vid vägarbete på motorväg: en jämförande studie2007Report (Other academic)
    Abstract [sv]

    Everyday life of road-workers is often fraught with danger. High speeds and disrespectful drivers many times make it hard to accomplish the work. High speed means short time between detection and passing the working zone and in event of an accident the consequences will be more severe. At the same time, road-users are bothered by the road-work and want to maintain accessibility. During springtime 2007 the Swedish Road Administration was offered to try alternative types of road equipment which are used in Germany. In connection to a planned paving work in May at the motorway E4 south of Gävle different types of equipment were established. In the light of this, the Swedish Road Administration ordered an evaluation of the equipments in question by VTI, which is shown in this report. The aim is to compare the equipments with each other and with the conventional equipment that is used in Sweden today. The three different types of equipment arrangements that were compared to the conventional Swedish one (only in daylight) were: - Like the conventional equipment, but signing using variable message signs (VMS) for the road signs "overtaking prohibited", "speed limit" (at 50 km/h the sign also flashed for speeding vehicles) and "left lane ends". The sign "left lane ends" was additionally supplemented with VMS "warning for other danger". - Like the previous, but with an arrow-formed pattern of the limited access on side marker instead of the conventional diagonal stripes and running light in the chicane. - Like the previous, supplemented by white plastic barriers in the chicane

  • 22.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Kantstolpar: en litteraturstudie utförd på uppdrag av NMF2008Report (Other academic)
    Abstract [sv]

    The literature review was made on commission by the Nordic collaboration NMF (Nordic meeting for improved road equipment). The commission was on synthesising knowledge of and regulations for post delineators in the Nordic countries. The review started with a broad approach where all literature on post delineators was searched in the databases TRAX and ITRD. After sorting out some of the material some references were ordered, after which a new sorting out was carried out along with supplementing the material with other references. In total, this report includes 31 references. The literature review consists of three parts: - Road user effects of post delineators. - The function of post delineators. - Regulations for post delineators in the Nordic countries.

  • 23.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Literature review on variable message signs (VMS) 2006-20092011Report (Other academic)
    Abstract [en]

    VMS can be used in a number of ways, for instance for information about speed, travel time, roadworks ahead, congestion, accidents, lane shift, weather, route guidance and events. During 2006-2009 a large number of studies regarding VMS have been completed, of which 61 are referred to in this report. Suggested areas of future research include graphic messages on VMS, legibility of VMS and information units.

  • 24.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Nedsläckning och reduktion av vägbelysning på motorväg2007Report (Other academic)
    Abstract [sv]

    In 2004, the Swedish Road Administration and the Swedish Association of Local Authorities published a handbook, VGU, on the design of roads and streets, in which one of the sections deals with road lighting. The main thought in the VGU is to reallocate means for road lighting from roads where the benefit for traffic safety is low, to roads where it is high. Consequently, good road lighting is primarily recommended on roads and streets where unprotected road-users, such as cyclists and pedestrians, pass. The aim of this project was to analyse the effect of reduced or turned off road lighting on motorways, considering road-user behaviour and attitudes. The intention was to use two existing motorway stretches for the trial, both with a large part of commuter traffic. On one road stretch, the existing road lighting should be reduced by half, while it should be completely turned off at the other. Interviews with commuters should be carried out after the lighting reduction, and speed measurements should be made before and after the reduction. Because of the strong negative reaction from one person living close to the road stretch where the road lighting was completely turned off and that this person contacted media, it was necessary to turn on the road lighting again. As a result of this, no attitude study could be accomplished, and no measurements of speed after the reduction on this road stretch were possible. Accordingly, it was only possible to make speed measurements on the motorway stretch where the road lighting had been reduced by 50 per cent.

  • 25.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Sammanställning av användning och utformning av varningslinjer i Norden: uppdrag inom NMF2007Report (Other academic)
    Abstract [sv]

    The aim of this study has been to compile the regulations and criteria for use and design of warning lines in Norway, Denmark, Sweden and Finland. Warning lines are used in all of the above-mentioned countries but with different designs regarding colour, width and intermittence. The use of the line is also differing between the countries. Generally, the warning line requests the driver to be careful and it can for example be used as a pre-warning for a succeeding no passing line, or to call for caution when changing lanes.

  • 26.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Samspel mellan vägbelysning och vägbeläggning med avseende på energiförbrukning2011Report (Other academic)
    Abstract [en]

    The aim of the project "Interaction between road lighting and road surface for reduced energy consumption", financed by the Swedish Energy Agency, was to study if it is possible to reduce road lighting and thereby save energy and money by using brighter pavements than those normally used. The study has been performed in two steps: Step 1 aimed to estimate costs for transporting stone material, maintenance and energy for road lighting, both when using conventional stone materials and brighter materials. In step 2, road surfaces in some Swedish municipalities have been audited by field measurements of the luminance coefficient of road surfaces. Under the premise that the road lighting construction has been dimensioned according to the existing regulations, the aim of this audit was to investigate if the actual road surface brightness would mean an over- or underestimation of the illuminance in the road lighting

    construction.

  • 27.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Svensk sammanfattning av COST 331: krav på längsgående vägmarkering2006Report (Other academic)
    Abstract [sv]

    The national technical specifications existing for road markings today include minimum performance levels on essential parameters (daytime and night-time visibility and skid resistance). It is desirable that the demands are based on both the driver's need of visibility and on what is possible to achieve with road marking. Road markings are in reality "traffic signals" which can be expected to have an impact on traffic safety, accessibility and comfort by guiding the driver along the road. Therefore, there has to be a scientific basis for answering the most relevant questions concerning design and use of road markings, such as: - What visibility distance does a road marking of a certain type and quality have? - What is the visual demand of the drivers, concerning road markings? The results from COST 331 give a scientific method for deciding the design of longitudinal road markings. This gives the necessary basis allowing research, industry and road traffic engineers to improve the road markings regarding the need of the drivers. The research programme, designed and approved by the COST 331 Management Committee, included the following phases: - 1. A review of the current use of road markings in Europe. - 2. An investigation of the visibility of road markings in a driving experiment. - 3. A study of the driver's need for visibility distances in a driving simulator. - 4. Registration of drivers' (test persons') behaviour in real traffic conditions by using an unobtrusive instrumented car. The results show that almost all countries have regulations and technical recommendations specifying geometry, design and colour of road markings. However, the road marking design varies between the countries. Also, in some countries the use of road markings made for improving the visibility in wetness and rain is prescribed. The difference between the regulations in different countries could be due to lack of a scientific base.

  • 28.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar i Danmark 20032004Report (Other academic)
    Abstract [sv]

    Tillståndsmätningar av vägmarkeringars retroreflexion kan till exempel

    utföras för

    att undersöka vägmarkeringars funktion samt för att fördela medel för drift-

    och

    underhållsåtgärder av dessa. Under år 2002 gjordes en pilotstudie i Norden i

    syfte

    att testa metoden för insamling av data tekniskt och administrativt samt för

    att

    undersöka hur många mätningar som skulle krävas vid ett framtida huvudförsök.

    Under år 2003 genomfördes huvudförsöket i Danmark, Norge, Finland och

    Sverige.

    Detta notat behandlar i huvudsak resultaten från Danmark, där amtsvägar från

    Ribe och Frederiksborg amt samt vissa statsvägar, underhållna av

    Vejdirektoratet,

    kontrollerats.

  • 29.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar i Finland 20032004Report (Other academic)
    Abstract [sv]

    Tillståndsmätningar av vägmarkeringars retroreflexion kan till exempel

    utföras för att undersöka vägmarkeringars funktion samt för att fördela medel

    för drift- och underhållsåtgärder av dessa. Under år 2002 gjordes en

    pilotstudie i Norden i syfte att testa metoden för insamling av data tekniskt

    och administrativt samt för att undersöka hur många mätningar som skulle

    krävas vid ett framtida huvudförsök. Under år 2003 genomfördes huvudförsöket

    i Danmark, Norge, Finland och Sverige. Detta notat behandlar i huvudsak

    resultaten från Finland, där vägar från distrikten Nyland, Åbo, Sydöstra

    Finland, Tavastland, Savolax-Karelen, Mellersta Finland, Vasa, Uleåborg och

    Lappland har kontrollerats.

  • 30.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar i Norge 20032004Report (Other academic)
    Abstract [sv]

    Tillståndsmätningar av vägmarkeringars retroreflexion kan till exempel

    utföras för att undersöka vägmarkeringars funktion samt för att fördela medel

    för drift- och underhållsåtgärder av dessa. Under år 2002 gjordes en

    pilotstudie i Norden i syfte att testa metoden för insamling av data tekniskt

    och administrativt samt för att undersöka hur många mätningar som skulle

    krävas vid ett framtida huvudförsök. Under år 2003 genomfördes huvudförsöket

    i Danmark, Norge, Finland och Sverige.

    Detta notat behandlar i huvudsak resultaten från Norge, där vägarna E6 och

    E18 genom distrikten Østfold, Stor-Oslo, Romerike, Hedmarken-Østerdalen,

    Vestoppland, Gudbrandsdal, Nedre Buskerud, Vestfold, Nedre Telemark, Aust-

    Agder samt Vest-Agder har kontrollerats.

  • 31.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringar i Sverige 20032004Report (Other academic)
    Abstract [sv]

    Tillståndsmätningar av vägmarkeringars retroreflexion kan till exempel

    utföras för att undersöka vägmarkeringars funktion samt för att fördela medel

    för drift- och underhållsåtgärder av dessa. Under år 2002 gjordes en

    pilotstudie i Norden i syfte att testa metoden för insamling av data tekniskt

    och administrativt samt för att undersöka hur många mätningar som skulle

    krävas vid ett framtida huvudförsök. Under år 2003 genomfördes huvudförsöket

    i Danmark, Norge, Finland och Sverige. Detta notat behandlar i huvudsak

    resultaten från Sverige, där 12 objekt vardera från regionerna Norr, Mitt,

    Mälardalen, Stockholm, Sydöst, Väst och Skåne har kontrollerats.

  • 32.
    Nygårdhs, Sara
    Swedish National Road and Transport Research Institute.
    Vägbelysning: en litteraturstudie2006Report (Other academic)
    Abstract [sv]

    During the recent years, the Swedish National Road Administration has shown an increasing activity in the field of road lighting, which among other things resulted in a new strategy for road lighting and a revision of VGU (the design of roads and streets). The ambition with this literature review is to cover the knowledge in the road lighting area to a large extent, concerning aspects like visibility, accidents, security, aesthetics, environment, energy, physical measuring and recommendations. The purpose is both to increase the knowledge of road and street lighting at VTI and to create a useful source in the area, where it will be possible to find references for deeper studies. The literature search has been carried out in the databases TRAX, TRIS and ITRD. A selection of references was collected for deeper studying, while the summary, only, was used in other cases. The resulting literature review contains almost 200 references, most European, published 1990-2005. This report includes themes such as visibility, relation between accidents and introduction of road lighting, lighting level and change of existing road lighting. Security and equality, especially for road users at walking paths and bicycle tracks, are other subjects that are discussed, as well as aesthetics, environmental and energy aspects. Finally, physical measurement and maintenance of road lighting, along with regulations, recommendations and further research are examined.

  • 33.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Field test on visibility at cycle crossings at night2010In: European Transport Research Review, ISSN 1867-0717, E-ISSN 1866-8887, Vol. 2, no 3, p. 139-145Article in journal (Refereed)
    Abstract [en]

    Purpose: The main purpose of the study was to compare the night-time visibility distance of cycle crossings to the nighttime visibility distance of bicyclists at the corresponding cycle crossings. This was tested both for dry and wet road surface. Methods: The test was carried out as a field study with twelve participants being passengers in an instrumented car. The test route included nine cycle crossings, that all were combined with pedestrian crossings. The participants individually pushed a noiseless button when they saw a dummy bicyclist standing still at a crossing, in part one, and when they saw a correctly marked cycle crossing in part two. Visibility: distances to bicyclist dummies and cycle crossings were measured. Half of the participants experienced dry road surface and the other half wet road surface. An analysis of variance was conducted with a split plot design of group (wet / dry road surface) × target (bicyclist dummy / cycle crossing) × crossing (9 different cycle crossings). Results: The bicyclist dummies were detected at a significantly longer distance (mean 59.1 m, standard error 2.9 m) than the cycle crossings (mean 17.5 m, standard error 1.0 m). The road condition (wet/dry) only had an effect on the visibility of cycle crossings. Conclusion: The field test showed that bicyclists are seen at longer distances than cycle crossings combined with pedestrian crossings in Sweden at night-time.

  • 34.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Carlson, Annelie
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Ihlström, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafikanttillstånd, TIL.
    Kriterier för vägbelysning på statlig väg i och i anslutning till mindre tätorter på landsbygd: Resultat från litteraturstudie, intervjuer och projektmöte2017Report (Other academic)
    Abstract [en]

    According to the prevailing road lighting guidelines, roads and streets in urban areas should be equipped with road lighting, while roads outside of urban areas normally do not need to be equipped with road lighting. Vägar och gators utformning (VGU) contains guidelines that are mandatory for public roads but advisory for municipality roads and streets. The need of road lighting on public roads outside of urban areas has been discussed between the road authorities, i.e. the Swedish Transport Administration and the municipalities.

    The aim of this study is to produce a proposal of new criteria for use of road lighting on public roads in and in connection to smaller populated areas in the countryside. This has mainly been done by a literature review of guidelines and research studies about road users’ needs and the effect of road lighting, as well as through interviews with persons responsible for road lighting in Swedish municipalities. A list containing possible criteria was compiled and discussed at a meeting with the project group for the project “Kriterier för belysning på statlig väg”, which is a group with common members from Swedish Association of Local Authorities and Regions (SALAR) and Swedish Transport Administration. The participants at the meeting found the following criteria interesting to apply.

    A public road on the countryside should be equipped with road lighting if:

    1. the road runs through an urban area
    2. there is a local plan where there is mixed traffic on a national arterial road
    3. there are establishments and services that generate vulnerable road users close by the road, e.g. schools, churches, community centers, gymnasiums, health care centers, museums, train stations, ferry quays or similar
    4. there are passages for pedestrians and cyclists or speed reducing measures along the road
    5. there are commuter stops, including train and boat
    6. prevailing requirements on AADT in VGU are fulfilled.
  • 35.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Fors, Carina
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Eriksson, Lars
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Field test on visibility at cycle crossings at night2010Report (Other academic)
    Abstract [en]

    This report describes a field study which is part of the project "Road user support in night-time traffic". The first steps in the project were a literature review on night-time traffic in urban areas and a focus group study where road users' needs and experiences of night-time traffic in urban areas were discussed. The aim of the field study was to compare the night-time visibility distance of cycle crossings to the night-time visibility distance of bicyclists at the corresponding cycle crossings. This was tested both for dry and wet road surface. Twelve volunteers participated in the study; six at dry road surface and six at wet road surface conditions. They sat as passengers in an instrumented car at night travelling along a test route including a total of 19 cycle crossings. The participants indicated when they noticed bicyclists (stationary dummies) and cycle crossings along the test route, and the visibility distance was registered and stored.

  • 36.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Helmers, Gabriel
    VMS - Variable Message Signs: A literature review2007Report (Other academic)
    Abstract [sv]

    This literature review is primarily aimed at describing studies that deal with the interaction between driver behaviour and variable message signs, VMS. The collected references are, for the most part, published in Europe or studies about European conditions, published during the years of 2000-2005. Areas treated in the study are effects on driver behaviour, driver attitudes, design, understanding and recall of VMS, and accidents and regulations concerning VMS. The literature review is supplemented by a behavioural background and recommendations from a behavioural science perspective.

  • 37.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Herrstedt, Lene
    Trafitec.
    Sörensen, Kai
    DELTA Light & Optics.
    Readability of variable message traffic sign2010Report (Other academic)
    Abstract [sv]

    This report describes a number of tests of the readability of variable message traffic signs that were carried out in a period from the spring of 2008 until the autumn of 2009. An even earlier test is not mentioned. A variable message traffic sign is called VMS in the following. The tests are described approximately in the sequence they were carried out. To some degree the sequence describes a "learning by doing" process in which later tests were based on earlier tests. All the tests involve presentation of a number of prearranged messages on a VMS, representing variation of some parameters supposedly related to the readability of the messages, to a group of test persons. In the early tests, the criterion for the readability was the reading distance of each of the messages for each of the test persons. In the later tests the criterion was rating of the readability at predetermined distances.

  • 38.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute.
    Ihs, Anita
    Swedish National Road and Transport Research Institute.
    Speglande reflexion i våta vägbeläggningar: störande ljus vid vägarbeten om natten: förstudie2006Report (Other academic)
    Abstract [sv]

    With respect to traffic, roadworks are to an ever increasing extent performed during the dark hours. In these cases, lighting is a critical factor to consider. It is important that the road-user experiences good visual guidance past the road work area and that he or she is not bothered by glare from road work lighting, reflections in the roadway and other things. The safety and road work lighting should at the same time be good for the roadworker. This report reports on a pre-study of the joint Nordic project Störande ljus vid vägarbeten om natten (Disturbing lights during roadworks at night). The purpose of the project is to improve the safety both for road-users passing a roadwork area in the dark and for the persons working at the roadwork area. This particularly applies to night-time roadworks on major roads. In the main project, the disturbance that the different elements - flashing lights, vehicle lighting, electric fittings, reflections, etc. - cause the driver passing the roadwork area will be investigated, both separately and combined with each other. The project should lead to proposals for improvement and co-ordination of current regulations in the Nordic countries. Reflections in the roadway, especially when the roads are wet, can be experienced as problematic for the road-users. If the road surface is damp, glare occurs, for example from oncoming vehicle headlights or from flashing lights and signs by the road work area. In this pre-study, an investigation of the specular reflection in some typical Nordic road surfaces has been made, aimed to form the basis for planning the main study. The purpose with the pre-study has principally been to survey what values of specular reflection, retroreflection and luminance coefficient are common for road surfaces in the Scandinavian countries Denmark, Norway and Sweden. Finland, which originally should also have been part of the study, has been excluded due to resource and time limits, for the present. Measurement of the specular reflection has been made on dry and wet road surfaces with a modified retroreflectometer (of the type LTL-X). It has been supplemented with a vertical mirror directing the observation direction towards the lighting direction in such a way as to correspond to a motorist observing a point on the road surface 30 metres in front of the vehicle, which is lightened by a headlight 30 metres further away. Since the instrument was relatively untested, the aim of this pre-study was also to acquire experience and routines for measuring specular reflection.

  • 39.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute.
    Läsbarhet av VMS: resultat från förförsök vid DTU2008Report (Other academic)
    Abstract [sv]

    Within the Nordic collaboration NMF (Nordic Meeting for Improved Road Equipment) it was agreed in 2007 that a project on legibility of variable message signs, VMS, would be started. This document reports on a pilot study of a subproject within this project, performed at the Technical University of Denmark, DTU. The questions at issue for the pilot study were to investigate how the legibility distance depended on luminance class, symbol thickness and space between symbols in daylight. Apart from this, the method of the study was also tested in practice. VMS pictures showing randomised two digit numbers were made. Luminance class was tested in two levels, symbol thickness in three levels and space between symbols in three levels. Six test subjects with satisfactory sight were instructed to walk from a start position at about 400 m away from the sign towards the sign to the point where they, separately, were completely sure of the combination of digits shown. The legibility distance between the VMS and the subject was registered, and the procedure was repeated with all the conditions.

  • 40.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute.
    Prediktionsmodell för våta vägmarkeringars retroreflexion2004Report (Other academic)
    Abstract [sv]

    Vägmarkeringars synbarhet i mörker och väta är av stor vikt. I syfte att

    skapa modeller för att kunna prediktera våta vägmarkeringars retroreflexion

    från mätningar av retroreflexionen vid torrt väglag gjordes två mätserier -

    en av VTI och en av Greenwood Engineering - i Danmark under hösten 2003.

    Retroreflexionen för torra respektive våta vägmarkeringar samt texturen på

    befintliga vägmarkeringar mättes då i två provfält. De profilerade

    markeringarna utgjordes till största delen av olika varianter av longflex,

    dropflex och rainline.

  • 41.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute.
    Tillståndsmätning av vägmarkeringarnas funktion i Norden 20032004Report (Other academic)
    Abstract [sv]

    Tillståndsmätningar av torra vägmarkeringars retroreflexion har gjorts i

    Danmark, Finland, Norge och Sverige under sommaren 2003. Syftet med dessa

    mätningar var att jämföra vägmarkeringarnas funktion inom och mellan

    länderna. Mätningarna utfördes med det mobila instrumentet Ecodyn 30 på

    absolut torra vägmarkeringar. De sträckor som har mätts är inte helt

    slumpmässigt valda, men ändå kan vissa intressanta jämförelser göras: I

    Danmark hade vägmarkeringar på statsvägar lägre retroreflexion än på

    amtsvägar i Ribe och Frederiksborg amt. I Finland hade vägmarkeringarna i

    Tavastland högre retroreflexion än övriga distrikt. För övrigt var skillnaden

    mellan distriktens vägmarkeringar liten. I Norge hade vägmarkeringarna på E18

    högre retroreflexion än de på E6. Variationen i vägmarkeringarnas

    retroreflexion längs vägen var stor i Norge. I Sverige har Region Sydöst

    förbättrat vägmarkeringarnas kvalitet påfallande mycket sedan mätningarna

    2002. En jämförelse mellan ländernas vägmarkeringar visar inte på några stora

    skillnader. Det noteras dock att de uppmätta vägmarkeringarna i Danmark 2003

    har högre retroreflexion än de som mättes 2002, vilket skulle kunna förklaras

    av ändrad urvalsstrategi: 2003 mättes endast vägmarkeringar som var mellan

    ett och fyra år gamla, medan någon sådan restriktion inte fanns året innan.

  • 42.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Tillståndsmätning av vägmarkeringars funktion år 2009 i SMN, SST och SSÖ2010Report (Other academic)
    Abstract [en]

    Starting in 2000, condition assessment of road markings have been carried out in Sweden. As previously, the purpose of the study has been to answer the questions: - To which degree is the performance in the Swedish regulations fulfilled? - Is there any difference in road marking quality within the same region, i.e. between the counties? - How has the performance fluctuated over time?

    The retroreflectivity and macro texture of dry road markings have been measured using the RMT version 2 in 2009. The retroreflectivity of wet road markings and the skid resistance have been estimated from the dry performance and the macro texture.

  • 43.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Tillståndsmätning av vägmarkeringars funktion år 2010 i SST, SÖ, SSY och SM2011Report (Other academic)
    Abstract [sv]

    Starting in 2000, mobile condition assessment of dry road marking retroreflectivity has been carried out in Sweden. Later, also the retroreflectivity of wet road markings has been estimated from the dry performance and the macro texture. As in 2009, this estimation is made for profiled markings on European highways (excluding lane lines). This year, 2010, the length of the measurement objects has been reduced from 20 km to 10 km with the aim of measuring more objects. This year also involved the transition of the Swedish National Road Administration into the Swedish Transport Administration (April 1st 2010), and a change of the administrative regions.

    As in previous years, there are several motives with condition assessments: - To which degree is the performance in the Swedish regulations fulfilled? - Is there any difference in road marking quality within the same region, i.e. between the counties? - How has the performance fluctuated over time?.

  • 44.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Lundkvist, Sven-Olof
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Andersson, Jan
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Dahlbäck, Nils
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    The effect of different delineator post configurations on driver speed in night-time traffic: A driving simulator study2014In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 72, p. 341-350Article in journal (Refereed)
    Abstract [en]

    The aim of the study was to investigate how different delineator post configurations affect driver speed in night-time traffic. In addition, the potential speed effect of introducing a secondary task was investigated. The study was carried out in a car simulator on a road stretch including straight road sections as well as curves with different radii. Fourteen drivers participated in the study and the results show that absence of delineator posts leads to reduced speed. However, provided that there are delineator posts continuously present along the road, the overall driver speed is basically the same, regardless of the spacing between the delineator posts. The results also imply that to reduce driver speed in curves with small radius, using more compact spacing of posts in these curves as compared to in curves with a larger radius, could be a potential strategy. Additionally, the speed reducing effect of a secondary task was only prevailing where the task was initiated.

  • 45.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute.
    Möller, Staffan
    Swedish National Road and Transport Research Institute.
    Halkvarnare för applicering på vägbanan: test av prototyp i laboratorium och i fält2008Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    In order to draw the attention of drivers to slippery conditions, ice warning

    sensors for application on carriageways have been developed. These are

    expected to react to the temperature of the road surface, which would be an

    advance compared with existing warning sensors in the vehicle that measure the

    air temperature. The aim of this project is to investigate the function of

    these types of ice warning sensors. This will be done both in a laboratory

    environment and in the field in the winter before and after the warning sensor

    has been exposed to the effect of studded tyres, snow ploughs and salting. The

    type of ice warning sensor that was available consisted of a yellow background

    plate with a symbol in the form of a snow star punched out from the middle.

    According to the manufacturer, this symbol was to change colour, from yellow

    to dark orange, at a temperature of +2°C. The test was divided into three

    stages, preliminary field tests on roads without traffic (Stage 1), laboratory

    tests in a controlled climate room (Stage 2), and field tests on roads both

    with and without traffic (Stage 3).

  • 46.
    Nygårdhs, Sara
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Nilsson, Göran
    Svenska Vägmarkeringsföreningen, SVMF.
    Legibility of road marking symbols in the roadway2015Report (Other academic)
    Abstract [en]

    The regulations concerning road markings have recently opened up more for use of symbols in the roadway. However, regulations for the dimension of road marking symbols vary even between the Nordic countries, and research on how the symbols should be designed is lacking. The aim of the ViP project described in this report was to establish guidelines for how symbols in the roadway should be extended along the road. In order to achieve the goal, a simulator study on legibility distances was carried out, followed by two minor field studies. In the simulator study, four two-character symbols and four three-character symbols were used; 55, 56, 65, 66, 55N, 56N, 65S, 66S. For each of four symbol sizes; 1.6 m, 2.5 m, 4.0 m and 7.5 m and each of four speeds; 30, 50, 70 and 90 km/h, one two-character symbol and one three-character symbol were presented to the driver. The simulator study resulted in a main effect of symbol size; the larger the symbol size, the larger the legibility distance. Another result was that the legibility distance decreased when the speed increased. As an attempt to check the results from the simulator a downscaled field study was carried out. The highest and lowest speed and the largest and the shortest symbol size in the simulator were used, although downscaled with a factor three. Comparing the results of the simulator and the downscaled field study, the speed effect was significant but weak, i.e. the effect size was small. To be able to establish if there is a speed effect that should be examined in a larger test, a validation field study was completed. In the validation field study, the symbol size was always 2.5 m and the travel speeds were 30, 50, 70 and 90 km/h, in correspondence with the simulator speeds. The results of the validation field study showed no speed effect. The simulator study in this project confirmed the logic of larger symbol sizes meaning longer legibility distances, but while the speed influenced legibility distance in the simulator this was not the case in the field. The legibility distances in the simulator were also shorter than in the field, possibly due to issues related to the graphics rendering. A conclusion from this is that in order to find out how much road marking symbols should be extended, supplementary field studies are needed. It is recommended that future studies include several symbol sizes but it would probably be sufficient to perform the tests at only two vehicle speeds; one low and one high. Data from such studies should also be used for developing the graphics rendering in the simulation.

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