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LED lighting or Light Emitting Diodes is a type of light source that is starting to be used in larger scale on pedestrian and bicycle lanes in Sweden and elsewhere. The project's aim was to study the traffic safety aspects of new lights and the interaction with the street environment for pedestrians and cyclists.

This project investigated the lighting conditions, effects on cyclists, and the interactions between lighting, traffic safety, street environmental conditions and/or other effects such as perceptions of safety for three different light sources (mercury vapour 125W, ceramic metal halide 70W and LED 25W) located in about the same type of street environment on a pedestrian and bicycle path on the Kungsholms strand in Stockholm.

Results show that the energy consumption of the LED lighting is 28% of the traditional mercury vapour lighting and 49% of ceramic metal halide lighting. LED may have slightly lower levels of illumination but with good light distribution of the luminaire, it is possible to achieve good uniformity. This study shows that it is possible to obtain sufficient uniformity levels with LED lighting but that the levels are dependent on the luminaire design, pole design and the number of poles per meter road (in this study the pole spacing was 15.3m). The number of LED poles required along a distance is higher than necessary for mercury vapour lighting and ceramic metal halide lighting, which currently makes the LED more expensive per kilometer illuminated path. The advantages of LED lightings are that the longevity is so much longer that in the longer time-scale perspective, it is possible to make substantial savings on energy, operating and maintenance costs.

There may be adverse effects of new energy-efficient lighting (on the number of single-vehicle accidents or perceptions of safety) if the pole spacing, illumination or uniformity is under dimensioned or if the fixture does not allow for good light distribution or if installations occurs in environments with many objects or other things that block the view. This study demonstrated no difference in cycle speed for LED lighting between daylight and darkness, or between different types of lighting.

Policies focusing on what is an acceptable lighting viewed from a combined view of traffic safety and perceptions of safety are currently missing, but is of high relevance for more energy efficient lighting. Without better guidance for the perceptions of safety there is a risk of installing new lighting with too low levels of illumination, thereby making the road and its surroundings less safe and unattractive for unprotected road users.

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Research area

Environment
Transport system
Traffic safety

  • Published: 2014-04-23
  • VTI-code: R816

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This report consists of three summaries of studies, conducted at VTI, concerning cyclists’ valuation of travel time savings on different types of bicycle paths and pedestrians’ valuation of travel time savings on footh paths. In the bicycle studies effects of health aspects have also been studied. All studies are questionnaire studies conducted with stated preference techniques.

The results show that the valuation of travel time savings are lower when cycling on a bicycle path than when cycling on a road way in either mixed traffic or in a bicycle lane in the roadway. Cycling on a path next to the road was not considering worse than cycling on a path not in connection to the road, indicating that the respondents did not take traffic noise and air pollution into account in their decision to cycle.
Respondents who included health aspects in their choice to cycle had lower value of travel time savings for cycling than respondents that stated that health aspects were of less importance, at least when cycling on a bicycle path. Valuations of travel time savings regarding cycling differed markedly depending on the respondents’ alternative travel mode, where persons with car as alternative travel mode had much higher values than those with public transport as alternative travel mode. The results showed that the largest shift to bicycle would happen if all cycling after the change takes place on a bicycle path far from the road.

For pedestrians, it was shown that individuals do not seem to prefer separated pedestrian and bicycle paths or completely secluded footpaths to the extent one might expect. The main thing seems to be that the walk takes place on a footpath of some sort and not along the roadside on a road with motor vehicles. Another result that is worth to highlight is that the visibility seems to be very important for which route people choose to walk. Other attributes such as maintenance, distance to a road with motor vehicles and type of crossing were not nearly as important.

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Research area

Transport system
Transport economics

  • Published: 2014-03-21
  • VTI-code: N11-2014

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This report describes the results of a survey including 1.133 people using a questionnaire covering factors that affect traveller´s intentions to cycle and how to get the "reluctant" rider to start cycling.

In the survey, participants were answering different questions based on two different theories (Theory of planned behaviour and The transtheoretical model of change) and were asked to link them to a journey they usually make in a week. Results showed that distance travelled was an important factor influencing modal choice although this was not the only one since attitude, social norms and perceived behavioural control were also important.

The participants were then divided into two groups; those who biked or used the car on a regular basis. Motorists were more negative to cycling and believed that it was sweaty, not particularly comfortable, and that it would make it difficult for them to carry out everyday activities. For the cyclists however, it was felt that the bike contribute to a sense of freedom, it was a convenient way to travel and it made them to feel more alert. Cyclists also argued that cycling helped to improve the environment, a view they shared with the motorists. Motorists and cyclists' views on the social norm were also different. The cyclists believed to a greater extent than motorists that their closest friends would accept that they biked and they were also more likely to mix with other cyclists.

The results show that people are at different stages in the change process and that measures should be tailored to the stage the group is at. At the earlier stages when the person still holds a negative attitude towards the new behaviour the focus should be on positive aspects of cycling that provide short-term rewards while the behaviour at the same time must be considered as a possible alternative. This also means that they must realize that their own behaviour brings a number of problems.

The study also showed that less attention is needed to convince people that cycling is good for their own health and the environment because they are already aware of this. If one is to persuade people that cycling is a great way to get around, the message must be believable and it must be easier to bike. People who try to ride a bike for the first time is an especially vulnerable group. If the new experience is a disappointment there is a great risk that you refrain from cycling in the future. This means that more attention must be paid to the physical environment. The important issue for planners and decision makers is whether the network enables one to ride in a fast and convenient way. But one should also ask that if enough measures have been taken to prevent road accidents and bicycle thefts.

To change behaviour takes time and the results from this study show that the motives depend on what stage of change the person is at, each stage has its own needs, and these needs should be taken into account when a program with the intent of increasing the proportion of cycling should be designed. This also mean that the approach taken has to be long term and that the strategy should be to define both main goals and sub-goals.

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Research area

Transport system
Planning and decision-making processes

  • Published: 2014-03-13
  • VTI-code: R797

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The background to this study is an inquiry by the Swedish Transport Administration to develop methods for benefit-cost analyses for pedestrians’ appraisals of their walking environment and how different improvements in the environment affect decisions to walk.

The issues studied are:
1. What type of road do pedestrians prefer when they choose which route to walk?
2. What is the willingness to pay to get more attractive footpaths?
3. How many persons will start to walk if it is built more attractive footpaths?

The third issue was unfortunately not possible to answer because of the low response rate in that part of the study.

One result from the study is that individuals do not seem to prefer separated pedestrian and bicycle paths or completely secluded footpaths to the extent one might expect. The main thing seems to be that the walk takes place on a footpath of some sort and not along the roadside on a road with motor vehicles. The visibility seems to be very important for which route people choose to walk. Other attributes such as maintenance, distance to a road with motor vehicles and type of crossing was not nearly as important.

Finally, it seems not impossible to investigate individuals' appraisals for various types of footpath attributes and choice of footpath using stated preference methodology. However, the interest in walking issues seems not to be high and many of the questions in the questionnaire seemed to be difficult to answer. To make it easier to clarify some of the ambiguities, future studies about pedestrian appraisals should involve some kind of interview methodology.

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Research area

Transport system
Transport economics

  • Published: 2014-02-21
  • VTI-code: R806

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open

Bicycle-friendly cities – the relevance of urban form and infrastructure

Year:
2014
VTI-code:
R769

Authors: Sebastian Bamberg , John Parkin , Aslak Fyhri , Kerstin Robertson

This report presents the results of a study with the overall aim of analysing the extent to which urban form and the design of the transport system can explain the level of cycling in cities. Distance was the most important factor associated with levels of bicycle use.

Bicycle traffic in cities can have several positive effects on quality of life. Despite these benefits bike share varies greatly between cities, both within and between countries, and in many cities there is a large potential for increased bicycle use. Better understanding of the causes of these differences is important for developing policies and measures that promote cycling.

The analysis is based on published studies of the relationship between cycling and various properties of the physical urban environment. The purpose of the study is to conduct a systematic review of relevant published studies and carry out a statistical meta-analysis of the relationship between cycling and various aspects of the urban physical environment.

The main contribution of this statistical meta-analysis is in providing a quantitative measure of their effects. Distance was the most important factor associated with levels of bicycle use, as would be expected. Land use, which was operationalised as measures of density and accessibility, was the second most important variable. Other variables in the analysis included the transport system, the urban environment and safety. The transport system variable was represented by measures of the street and bicycle network density, and the presence and quality of infrastructure for cycling. The urban environment covered various properties such as type of housing and neighborhood, but also aesthetic qualities and attractiveness, and safety included both safety and security. The findings agreed well with the results from the analysis of conclusions in published reviews addressing these issues.

With some allowance for the difficulties to demonstrate causality, we suggest that these aggregate variables are relevant for local planning aiming at increasing cycling. There is also a good consistency between studies of different physical factors on urban cycling, but if the goal is to develop support and guidance that can be used in practical planning, more specific factors need to be carefully considered. Detailed models of the effects of various factors are obviously of relevance and importance to improve our knowledge and understanding, and it is important that this information is communicated and made available to policy-makers and planners. The relative significance of different factors in different cities must however be derived from such basic knowledge combined with professional knowledge about local conditions.

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Research area

Environment
Transport system
Planning and decision-making processes

  • Published: 2014-02-19
  • VTI-code: R769

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On behalf of the governmental agency Transport analysis VTI has analysed the consequences of the stricter sulphur regulations for marine fuel with the Swedish national freight transport model Samgods.

The base scenario has been compared with, in total, 18 analysis scenarios developed by Transport analysis. The reason for the large amount of scenarios is the fact that both the technical and the economic development (related to the sulfur directive) is uncertain and needs to be taken into consideration.

The results show that the demand for sea transports on the Swedish territory (in tonne-km) is indicated to be rather inelastic. In scenario High 1 the sea tonne-km are calculated to decrease by 0.7 billion (about 2%) due to 40–76 per cent higher sea transport costs (depending on type of ship) all other costs kept unchanged.

For rail, the tonne-km are increasing maximum by 0.9 billion (about 4%). This is the case for scenario High 3 with the highest assumed increase for sea and road transports. The results for rail should be interpreted as potential increases since the model does not take into account capacity restrictions.

For road, the tonne-km are calculated to decrease in Sweden with a maximum of 0.6 billion (about 2%) in the scenarios Low 3 and Low 3B.

In this report changes in freight flows, tonnes per route and mode, are illustrated in maps showing the difference between the base scenario and the different analysis scenarios. For road, the overall pattern is indicating a redirection of the volumes from the ports along the Swedish east coast to ports on the Swedish west coast and to the ferry lines in the south.

Finally, the results should be interpreted with caution since they are based on a test version of the Samgods model. However, we still believe that the results on an overall level seem to be reasonable.

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Research area

Transport system

  • Published: 2014-01-23
  • VTI-code: N33-2013

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open

Development of validation tool and collection of ITS-based validation data for freight models

Year:
2013
VTI-code:
R804

Authors: Rune Karlsson , Inge Vierth , Christian Udin , Pia Larsson-Wijk , Abboud Ado , Fredrik Söderbaum , Magnus Johansson

This report deals with questions concerning validation of the Swedish national goods transportation model, Samgods. To some degree, also more general issues of validation are discussed.

When developing transportation models it is essential to have independent data available that can be used for comparison, validation and calibration. The quality and availability of such data are obvious issues. It is a big advantage if these data cover many different aspects of the model results and are collected on a regular basis.

In the report, a survey of data sources useful for validation purposes is presented. For each source of data, quality and availability is discussed. For statistical data, the method for collecting the data is described in some detail as well as uncertainties and access to the data that may be restricted due to privacy regulations.

There are reasons to believe that in the future new technologies will provide us with new types of data useful for validation or model estimations. A special section in the report is devoted to investigating if present day ITS systems can provide data for validation purposes.

Once the compilation of validation data is completed, many problems remain concerning the validation. In particular, there is a matching problem between the model output data and validation data. The many different table formats and aggregation levels for the data add to the complexity of this problem. A similar, but easier, problem is to compare output data from different versions of Samgods. Within this project a computer program has been developed that can be used for matching such kinds of datasets. The program, as well as a user manual for it, is included in the report. The possibility to handle some of the issues concerning confidential data, by using the program, is briefly touched upon.

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Research area

Traffic analysis
Transport system

  • Published: 2013-12-20
  • VTI-code: R804

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open

Sustainable Tourist Travel in Sweden

Year:
2013
VTI-code:
R782

Authors: Kerstin Robertson , Hans Antonson , Gunilla Sörensen , Anna Niska , Annika Jägerbrand , Anders Genell , Björn Arvidsson , Katarina Evanth , Nina Hvitlock , Jan Lundin , Hanna Wennberg

When summer holiday is upon us maybe you're thinking of travelling by train or bus instead of taking the car. VTI has studied Swedish tourism and compared both travel time and prices.

Interest in tourism is increasing and according to recent statistics, tourism's total sales in Sweden increased by 6.4 percent to 264 billion in 2011 and the sector employed 160,000 people. The study by VTI, “Sustainable tourism trips within Sweden. Obstacles and opportunities for travel by train and bus” includes travel time, expenses and interviews. The study included three summer destinations, Astrid Lindgren's World, Glasriket (the Kingdom of Crystal) and Öland, and two winter destinations, Åre and Funäsdalen.

– The purpose of this study was to analyze the conditions for travel by train and bus to the Swedish tourist destinations instead of travelling by car. The report shows that it is possible to travel to all places by public transport but conditions vary widely, says Kerstin Robertson, research director at VTI.

The study showed that it is difficult for families with small children to travel on public transport for several reasons. Luggage was one major issue. Several families also stated that it should be easier to find information about how to reserve public transportation tickets. Guides are in demand because of the problems to look for trips, accommodations, transfers and tickets in several different places or websites. The travelers would therefore appreciate if everything was gathered in one place.

The business is looking for better infrastructure and other measures to increase accessibility while travelers demand easier and more convenient booking and all inclusive packages.

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Research area

Environment
Transport system

  • Published: 2013-05-28
  • VTI-code: R782

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The purpose of this report is to give an account of the studies and tests carried out in Sweden with longer and heavier trains since the early 1990-ties. Before any further development work is carried out, the following conclusions, from the material presented in this report, are highlighted for consideration:

• There have been a very limited number of specific tests for heavy and long trains in Sweden. The supporting documents, obtained within the framework of this project, describe tests and investigations which were carried out since the early 1990s.

• With regard to heavier trains, embankment and bridge bearing capacity is a limiting factor for trains with high axle loads (e.g.stax 25 tonnes) and tonnes per metre (e.g. stvm 8 tons/m or more). Pending upgrade of tracks and bridges, these limitations can be handled by introducing speed restrictions on the sections with weak bearing capacity.

• The limitations for long trains are mainly linked to the length and number of sidings required to operate 750 metre (or longer) trains. The available track length at the shunting is also a factor that limits the possibilities to assemble and dismantle long trains.

The material for this report is based on investigations carried out by the Swedish Rail Transport Administration (Banverket, since 2010 Trafikverket) in cooperation with i.e. the Swedish States Railways ( SJ Gods, since 2000 Green Cargo) and other rail operators (MTAB) and shippers (i.e. LKAB, SSAB, Ovako), the Norwegian Rail Administration (Jernbaneverket) and the Swedish counties Gävleborg and Dalarna, Additional information has been obtained through interviews with people from Trafikverket who have previously worked at Banverket.

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Research area

Transport system

  • Published: 2013-05-17
  • VTI-code: N13-2013

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At Transportforum 2013 the participants had the opportunity to send in a manuscript for peer review. The papers have been reviewed by the members of the subject committees. Out of 40 notifications of interest, nine papers were published.

Three of the papers are written in English:

• Torbjörn Stenbeck, Riksrevisionen: Comparing productivity means to measure design-build pay-off.

• Björn Hasselgren, KTH: Pricing principles, efficiency concepts and incetive models in Swedish transport infrastructure policy.

• Maria Öberg, LTU: How to create a transport corridor management – a literature review.

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Research area

Environment
Transport system
Pavement Technology
Transport economics
Traffic safety

  • Published: 2013-05-02
  • VTI-code: R787

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