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  • Asplund, Disa
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Westin, Jonas
    CERUM, Umeå universitet.
    Modellering av slingor inom sjötransporter2017Report (Other academic)
    Abstract [en]

    The Swedish national freight transport model system Samgods is a freight model that simulates logistics decision at a disaggregated firm-to-firm level. The model calculates total annual transport demand in Sweden for all transport modes based on a deterministic cost minimization approach. The model cannot consolidate commodities of different commodity types in the same vessel, train or truck and can only simulate vessels using direct routes between two ports. This implies that many of the features of sea transport such as utilizing larger vessels and building loops to consolidate goods from different ports is not possible in the current Samgods version. In this paper, we analyze the effect of removing restrictions in sea transportation especially by allowing the ship operators to construct and utilize loops. In the new model, LIFREM (Loops Including FREight Model), the shippers’ choice of sea transport routes is modelled as a mixed integer linear programming optimization problem. In doing so, we make use of a case study on sea transport of forest products from Northern Sweden to Western Europe. The results show that allowing predefined loops decreases total logistic cost by 10% and allowing the shipper to freely select loops decreases the cost by 21%. These results show that modelling of loops is important in order to realistically represent the attractiveness of the sea transport mode. This is also confirmed by the fact that the sea mode share increases by 2–4% in LIFREM when loops are allowed.

  • Lundberg, Thomas
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Andrén, Peter
    Datamani.
    Thorsenius, Johanna
    Trafikverket.
    Lindström, Fredrik
    Trafikverket.
    Trafikverkets upphandling av vägytemättjänsten för vägnät 2014 för perioden 2015–2018 (2019): vägnätsmätning med mätbil2017Report (Other academic)
    Abstract [en]

    The Swedish Transport Administration (Trafikverket) annually monitors the condition of the national road network with survey vehicles. This is an operation that is, in principle, still carried out using the same technical basis as in 1986. During this time, however, measurement quantities have increased, measurement quality has improved, and measurement methods have been refined. In addition to monitoring the road network condition, the purpose of measurement surveys is to provide an information base that can be used to support investment decisions and maintenance planning. Condition measurement data can be used at an initial stage to identify potential maintenance candidates. Further investigations, carried out by project leaders, can then be used to determine which of the candidates are selected for maintenance action. The Swedish Transport Administration would ultimately like to be able to describe road conditions derived from surface measurement surveys even more accurately. This would allow project leaders to make more objective maintenance action decisions.

    With technical support from the Swedish National Road and Transport Research Institute (VTI), the Swedish Road Administration carries out the procurement of road surface measurement survey services. Road surface measurement services, for the period 2015 to 2018 (plus option year 2019), were obtained through a selective procurement process. Out of six suppliers who were invited to participate, three accepted the invitation to take part in the technical tests. The purpose of the tests is to examine the supplier’s ability to perform during simulated production conditions and be able to carry out the measurement surveys in accordance with pre-described conditions and specified limits. This report summarizes the results of the technical tests.

  • Ridderstedt, Ivan
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Pyddoke, Roger
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Vilka reser med kollektivtrafik i lands- och glesbygd?: demografi och resmönster2017Report (Other academic)
    Abstract [en]

    The Swedish government has commissioned VTI to study and assess innovative and efficient solutions for public transport in rural areas. To be successful in this task, it is essential with comprehensive knowledge on how the Swedish rural population travels, especially on the demographics and traveling patterns of today’s users of public transportation. This should also be of great interest for policy makers. Political goals linked to accessibility and environmental issues have contributed to an intensified discussion on how to improve public transport in rural areas whilst also considering the ever-present budget constraints. Arguably, improved knowledge on present traveling patterns enhances the possibilities of finding effective and economically sound solutions.

    Previous Swedish studies have described the general travel patterns and the distribution between transport modes, but they have not gone into depth on how public transport is used in rural areas and by whom. Moreover, these studies have usually applied a municipality based definition of rural areas which is likely to cause significant noise in the statistics due to its roughness. There are often several towns and urban areas even within dominantly rural municipalities, and there may be areas of rural character in more densely populated municipalities. Altogether, there is a need for a new study of the national traveling statistics with:

     focus on public transport in rural areas

     greater precision in how statistics from the national travel habit survey is linked to the countryside.

  • Hellman, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Ullberg, Johan
    Trafikverket.
    Skillnader i vägens uppbyggnad i tvärled: en analys av parallell provtagning utmed tre äldre vägar2017Report (Other academic)
    Abstract [en]

    For many years, reconstruction of roads has been built on the sampling of existing materials in the road structure. There are various methods to accomplish this, which means more or less damages in the road. From experience, we know that it may differ in material layer build up depending on where the roadbed samples are taken. Sides of the road may differ; slope and road surface often have different structure which makes it critical were sampling was done laterally in the road structure.

    Efforts in a reconstruction is to obtain as similar final product as possible, i.e. about the same service life along the entire route. If you get significantly different results along the route it may result in maintenance operations must be carried out earlier or later than expected. Previously Scheduled actions can be if they are extensive clearly increase the cost of a LCC perspective (Life Cycle Cost), while oversizing on the other hand can result in increased costs in the construction phase. For Road Administration planning, it is important that the right action is taken. It must be a balance between representativeness, road safety and cost when selecting sampling method.

    During three bearing capacity projects on existing roads in northern Sweden it has been sampled from both the road verge and the roadway. Sampling has been done to receive layer structure build-up from each sampling method on each section.

    The purpose of the study is to examine whether there is a difference between the two sampling methods, and if there is a risk that the wrong reconstruction action is selected based on the results. The report presents results from sampling along three roads, road 779Andersfors–Storbrännan, 897 Ålund– Jakobsfors and 726 Bygdsiljum–Burträsk. The results have been analysed whether there are systematic differences or similarities between the location of sampling and how these are related to the Transport Administration's rules for sampling, as described in TDOK2014: 0151 "Sampling of unbound materials."

  • Arvidsson, Anna K
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Krav för att förhindra fallolyckor: tekniska egenskapskrav för gator och vägar2017Report (Other academic)
    Abstract [en]

    Since injured pedestrians due to falling contributes to high costs for society, therefore the attribute requirements on a road surface is of great importance for safety. The requirements shall be appropriate for all who are on the surface, this applies to both vehicles, cyclists and pedestrians. This report summarises recent accident studies and the prevailing rules regarding the construction of spaces for pedestrians.

    In addition to these compilations an analysis is done of how common it is that people fall due to, for example, uneven surfaces, kerb-stones or stumble. In 38 percent of the reported accidents that occurred between 2008 and 2015 (82,559), the victims said that the accident happened on a footpath/pavement. To give a good picture of how many accidents that may occur due to surface and paving was 4,443 accidents filtered out, and all the descriptions were read and divided into 12 various categories. The most common reason to a person being injured, according to themselves, was unevenness, holes and pits, level differences or related to the stone/tile surface. The social-economic cost for these 4,443 accidents was in average 845 thousand SEK.

  • Ekström, Camilla
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafiksäkerhet och trafiksystem, TST.
    Linder, Astrid
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafiksäkerhet och trafiksystem, TST.
    Fatally injured cyclists in Sweden 2005–2015: analysis of accident circumstances, injuries and suggestions for safety improvements2017Report (Other academic)
    Abstract [en]

    Cycling is part of the sustainable transport system and plans are in place to increase this part of the transport system in Sweden, Europe as well as globally. Improving the safety for this group of roadusers is of great importance. The aim of this study was to identify patterns among fatally injured cyclists in Sweden, in order to suggest general safety improvements or improvements addressing different groups of cyclists as well as specific traffic conditions.

    The information was sourced from the in-depth study database of fatalities as well as the joint register for police and hospital injury and accident data, STRADA, in Sweden. Data was analysed and interpreted for an 11 year period from 2005–2015. The in-depth study of the fatalities provided details about the accidents and individuals involved in the accident and the information was retrieved by parameter values, in free text description and documents in the database. STRADA was used to sort official data within the in-depth study, assigning codes for accident type, complementing parameters and additional parameters.

    A total of 271 fatalities were identified and analysed where the majority of the accidents occurred during spring–autumn. Male fatalities accounted for two-thirds of the studied cases and in ages above 40, male fatalities are twice as many as female fatalities. Fatalities in Motor vehicle accidents are distributed in all age groups, while in the Single bike and Other bike category, there were no children and only a few young adults reported.

  • Wenäll, Jan
    Swedish National Road and Transport Research Institute, Infrastructure, Crash safety.
    Markens betydelse för vägräckens funktion: FUD RT Vägkroppens betydelse för vägutrustningars funktion2017Report (Other academic)
    Abstract [en]

    Background; Trafikverket (the Swedish Transport Administration) was asking for enhanced information about interaction between soil grading, bearing capacity and type approved vehicle restraints systems.

    Purpose: To get enhanced knowledge about interaction between soil grading, bearing capacity and type approved vehicle restraints systems.

    Method: Dynamic testing with an impact sled, some static push/pull tests and finally some full-scale crash testing with a passenger car into a barrier.

    Results: Barrier posts should not have a shorter length below ground level than 1.0 meter. A slope shoulder behind a barrier installation should not be arranged closer than 0.6 meter behind the same. In soil with less bearing capacity or compact ability it is probably possible to enhance barrier functionality by using even longer barrier posts, with a larger proportion of the post being inserted into ground.

  • Hjort, Mattias
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Förare och fordon, FOF.
    Gustafsson, Susanne
    Swedish National Road and Transport Research Institute, Traffic and road users, Trafiksäkerhet och trafiksystem, TST.
    Henriksson, Per
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Forsman, Åsa
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Tunga lastbilars däckanvändning och olycksrisk vintertid2017Report (Other academic)
    Abstract [en]

    In Sweden, it is today regulated that winter tyres must be used on the drive axle of heavy vehicles (total weight in excess of 3,500 kg) during the winter season period, December 1 to March 31, in case of winter conditions. This requirement is based entirely on accessibility, and it is considered that winter tyres on the drive axle provides better conditions for heavy vehicles to go forward in icy and snowy conditions. Previous accident risk studies have not been able to demonstrate that the use of winter tyres instead of summer tyres for heavy vehicles in winter could lead to reduced risk of accidents. In Norway and Finland, the regulations on tyre use for heavy vehicles in winter time has recently been revised. Prior to a discussion of possible regulations in Sweden on winter tyres also on other axles, there is reason to update the previous accident risk studies. The purpose of this study has been to calculate the risk of accidents on ice/snow conditions for comparison between summer and winter tires for heavy trucks. The study was performed according to the method previously used in the VTI studies conducted in 2000 and 2008. This meant that two questionnaires were sent out by the end of the winter 2015/2016. One survey to analyse the vehicle mileage on ice/snow conditions with different combinations of tires, and one questionnaire directed solely to the vehicle owners whose vehicles according Strada during the winter season have been involved in an injury accident. Accident risk calculations were limited to vehicles with a total weight of 16 tons.

  • Hedegaard Sørensen, Claus
    DTU - Technical University of Denmark.
    Videns anvendelse og indflydelse i dansk hastighedspolitik2013In: Artikler fra Trafikdage på Aalborg Universitet, 2013, 13- p.Conference paper (Other academic)
    Abstract [en]

    Hastighed er af afgørende betydning for trafiksikkerhed, og høj hastighed er anerkendt som en væsentlig udfordring for at reducere antal dræbte og tilskadekomne på vejene. Forskning i trafiksikkerhed handler ofte om hastighed, men anvender sjældent et politologisk perspektiv. I dette paper anvendes imidlertid et sådant perspektiv i et studie af formel videns anvendelse og indflydelse i danske, nationale politiske beslutninger om vejhastighed. En case-studie metode er anvendt og Folketingets beslutning i 2003 om at øge hastighedsgrænsen på motorvejene og en beslutning fra 2004 om at indføre klip i kørekortet ved bl.a. visse overskridelser af hastighedsgrænserne er analyseret. Empirien består i begge cases af dokumenter fra lovgivningsprocessen, andre offentligt tilgængelige rapporter og notater, nyhedsartikler, sagsakter fra involverede ministerier og kvalitative interviews.

    I begge cases analyseres brugen af et bestemt viden-dokument. Viden-dokumenterne anvendes i det lovforberedende arbejde og i det ene tilfælde citeres dokumentet flittigt under Folketingets behandling. Anderledes med dokumenternes indflydelse på beslutningerne. Det ene dokument influerer formentlig embedsmændende arbejde med lovforslaget, mens ingen af dokumenterne ser ud til at have indflydelse på den politiske behandling af lovforslagene. Viden-dokumenterne ændrer næppe nogle politikeres synspunkter. Viden-dokumenterne spiller i den ene case roller, vi betegner som ’viden som instrument’ og ’viden som argument’ og i den anden case en rolle vi betegner ’viden som rationalisering’. En udbredt konsensus om trafiksikkerhed som central værdi i hastighedspolitikken bidrager til forklare de observerede viden-roller.

  • Ejsmont, Jerzy
    et al.
    Technical University of Gdańsk.
    Sandberg, Ulf
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    ͆wieczko-Zurek, Beata
    Technical University of Gdańsk.
    Mioduszewski, Piotr
    Technical University of Gdańsk.
    Tyre/road noise reduction by a poroelastic road surface2014In: INTERNOISE 2014 - 43rd International Congress on Noise Control Engineering: Improving the World Through Noise Control, 2014Conference paper (Refereed)
    Abstract [en]

    Low noise road surfaces of existing types may in favourable cases and in new conditions provide up to 7 dB of noise reduction. For higher noise reductions, innovative solutions must be sought. Poroelastic road surfaces (PERS) may be such a solution, which currently is studied in the EU project PERSUADE. This paper presents results of trials with a PERS version prefabricated by one of the project partners. Tests were made in a laboratory at TUG, where different tyres were tested on drums covered with PERS, and later field tests were made on a local street in Sweden where VTI had constructed a 25 m long trial section. The field tests were made with a CPX trailer from TUG. Both laboratory and field results showed that tyre/road noise reductions of 9-11 dB were achieved compared to a dense asphalt concrete pavement with maximum aggregate size 11 mm. This is the best result so far in the project. At the same time, this PERS, despite being relatively soft, reduces rolling resistance of passenger car tyres to record-low values, which is important for reducing fuel consumption and CO2 emissions. It is concluded that this type of prefabricated poroelastic road surface offers a very efficient way of reducing tyre/road noise, provided current durability problems can be solved.

  • Viman, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Stickprov vid utförandeentreprenader: jämförelse mellan ”riskytor” och övriga ytor på några vägobjekt2017Report (Other academic)
    Abstract [en]

    The purpose of this project was to evaluate how the homogeneity can be measured and quantified over a section with newly laid asphalt pavement and determine how the properties varies from defined risk areas and other areas. This can be summarized in three different questions:

     Question 1: What methods are available to measure the homogeneity of newly laid asphalt pavements?

     Question 2: How much will the properties of the surface identified as risk areas, compared to other areas, vary over a defined asphalt pavement section?

     Question 3: Are the results from the contractor’s quality control equal to results from “risk areas” or “adjacent areas”?

  • Arvidsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Jämförande provning – ballast 2015: flisighetsindex, korndensitet och kulkvarn2017Report (Other academic)
    Abstract [en]

    This report shows results, some statistical analysis and precision data for profiency testing (round-robin) performed on three materials of aggregate during 2015. The properties that was determined was Flakiness Index (EN 933-3), particle density (EN 1097-6) and Nordic ball mill (EN 1097-9). The number of participating laboratories were for Flakiness index 58 pcs., for particle density 60 pcs. and for Nordic ball mill 52 pcs.

    There are some scatter of the results which is not surprising. A few of the laboratories show clearly high or low results (for all three materials) for one of the analysis. Generally is the scatter in results varying. E.g. some of the laboratories have a clearly high result for one of the materials, a slightly low result for the second material and are quite close to the average for the third material.

    The standard deviations increase with increase in level of results (average), but not as much. The ratio of standard deviation and average decrease with increase of level.

    The precision data from this round-robin over all matches the levels from the test standards. The tests from this report has often a wider range of results. There is a correlation between reproducibility and level of average. The repeatability has not been calculated because tests actually have been performed as single tests.

    Analysis of background data, like handling, dimensions and type of model, shows that they have none or very little significance.

  • Nilsson, Jan-Eric
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Johansson, Anna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Österström, Johannes
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics, TEK.
    Arlandabanan: konsekvenser av förändrade strategier2017Report (Other academic)
    Abstract [en]

    In year 2000, railway operations started between Arlanda airport and downtown Stockholm. The service is part of a PPP contract that includes construction and maintenance as well as service provision for a period of 45 years after the initiation of traffic. Patronage on the line is below expectations at the time of contract closure in 1993. There is therefore an ongoing discussion of whether it would be appropriate for the government to renegotiate the contract to change the preconditions for the service. Commissioned by Riksrevisionen, the Swedish National Audit Office, this memo addresses two aspects of a possible change of strategy:

     Which would the consequences be of a change of pricing strategy from the current targeting of the high end of the market? A 30 percent price reduction is considered.

     Is there enough track capacity to increase the number of departures during peak hours?