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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Determinants and deterrents of urban cycling : evidence from Europe</title>
      <link>https://trid.trb.org/View/2666531</link>
      <description><![CDATA[Urban cycling contributes to climate-neutral and resilient mobility, and its uptake hinges on a blend of behavioural, environmental, and infrastructural forces. This licentiate thesis brings together evidence from three empirical studies conducted in Braga, Istanbul, and Tallinn (papers A and B), as well as Paris and Barcelona (paper C) to identify and quantify drivers of cycling and to translate findings into insights that matter for policy. The first paper shows that a GPS-verified, gamified reward scheme, involving roughly 1,500 participants increased weekday cycling. The second paper applied mixed ordinal probit models to six months of data from the same reward scheme and finds that higher wind speeds and private-car ownership reduce weekly cycling, whereas public-transport use boosts it. The third paper employs ARIMAX time-series models of bicycle counts and identifies a pandemic step change, accounting for about 35,000 added bicycle trips per week in Paris and 26,000 trip per week in Barcelona. It also finds the added effects of infrastructure initiatives and lockdown stringency. The three studies highlight three overarching drivers of cycling: behavioral incentives, environmental conditions, and rapid-built infrastructure. These factors contribute to explaining when, where, and for whom cycling gains materialize. This thesis contributes with robust multi-city evidence, suggesting that targeted rewards, wind-protected lane design, car-access management, and transit integration can speed up modal shifts. It provides guidance to sustain and grow urban cycling across diverse city contexts, aligned with European climate goals.]]></description>
      <pubDate>Thu, 05 Feb 2026 08:33:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666531</guid>
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      <title>Lösningar för snabbare utveckling av skogsbilvägar i Sverige</title>
      <link>https://trid.trb.org/View/2534317</link>
      <description><![CDATA[]]></description>
      <pubDate>Fri, 04 Apr 2025 15:16:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2534317</guid>
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      <title>Koll på kostnaderna : kartläggning av Trafikverkets digitala infrastruktur för kostnadskontroll</title>
      <link>https://trid.trb.org/View/2534188</link>
      <description><![CDATA[The Swedish infrastructure manager Trafikverket has repeatedly received criticism for lacking the necessary conditions to monitor the agency's output, outcomes, and costs. These shortcomings limit both the Parliament's and the Government's ability to make well-informed decisions regarding Trafikverket and the national transport infrastructure, as well as the agency's internal management and operational development. To address these issues, Trafikverket has initiated several large and costly development projects for new IT systems and improved information management. This report aims to provide an updated description and assessment of Trafikverket's digital infrastructure for central monitoring of cost control in its construction and maintenance operations. The survey is based on interviews with managers and project leaders for a selection of prioritized IT systems, governing documents and observations of the systems. The survey was conducted by VTI on behalf of Transport Analysis. We find that Trafikverket is undertaking several initiatives that could lead to significant improvements in central monitoring of operations and cost control. Of particular importance are two new IT systems that gather information on completed work and payments, increased use of data warehouses for storing and accessing information from various systems, and efforts to harmonize the terminology structure into a common information model. However, we find that these initiatives, like several others identified in the survey, are delayed and have faced difficulties in the implementation phase. Compiling information across multiple investment projects or maintenance contracts remains difficult and resource-demanding. We find that significant effort is required from Trafikverket's internal governance to complete ongoing improvement initiatives and integrate them into a well-functioning whole.]]></description>
      <pubDate>Fri, 04 Apr 2025 15:14:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2534188</guid>
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      <title>Erhöhung der höchstzulässigen Gesamtlänge für Lang-Lkw durch Ausstattung mit emissionsfreien Antrieben und/oder aerodynamischen Anbauten</title>
      <link>https://trid.trb.org/View/2431334</link>
      <description><![CDATA[Das Forschungsprojekt soll wissenschaftliche Erkenntnisse zur Frage liefern, welche Herausforderungen für den Einsatz von Lang-Lkw entstehen könnten, sofern eine technische Ausstattung mit emissionsarmen Antrieben und/oder aerodynamischen Fahrzeugfronten unter der Voraussetzung erfolgt, dass die technischen Anpassungen weder eine Reduzierung der Ladelänge noch eine Änderung der technischen Vorgaben für Führerhäuser nach sich ziehen soll. Die Umsetzung dieser Voraussetzungen hätte eine Erhöhung der höchstzulässigen Gesamtlänge für Lang-Lkw zur Folge, deren Auswirkungen bisher unerforscht sind. Es soll untersucht werden, inwieweit eine Erhöhung der höchstzulässigen Gesamtlänge in Paragraf 4 Absatz 1, 2 und 3 der Ausnahme-Verordnung für den Einsatz von Lang-Lkw (LKWÜberlStVAusnV) durch verlängerte Lkw-Führerhäuser oder die Ausstattung mit emissionsfreien Antrieben (Wasserstoffspeicher hinter dem Führerhaus) möglich ist und welche neuen Anforderungen sich hieraus unter Umständen für den Einsatz von derartigen Lang-Lkw ergeben. ABSTRACT IN ENGLISH: The aim of the research project is to provide scientifical findings on the question of what challenges could arise for the use of long trucks if these are technically equipped with low-emission drives and/or aerodynamic vehicle fronts, provided that the technical adaptations do not result in a reduction in the loading length or a change in the technical specifications for driver's cabs. The implementation of these requirements would result in an increase in the maximum permissible overall length for long lorries, the effects of which have not yet been researched. It is to be investigated to what extent an increase in the maximum permissible overall length in Section 4 (1), (2) and (3) of the Exemption Ordinance for the use of long lorries (LKWÜberlStVAusnV) is possible with extended cabs or with emission-free drives (hydrogen storage behind the cab) and what new requirements may result from this for the use of such long lorries.
]]></description>
      <pubDate>Wed, 25 Sep 2024 05:30:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2431334</guid>
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      <title>Road Safety Action Plan 2022-2025 : 250 measures that 33 authorities and stakeholders intend to implement to increase road safety</title>
      <link>https://trid.trb.org/View/2388975</link>
      <description><![CDATA[Since 2018, the Swedish Transport Administration has been tasked by the Government to lead overall collaboration on road safety work. This assignment means that the Swedish Transport Administration must lead the collaboration in a way that creates a continued and increased commitment and responsibility among the relevant authorities and stakeholders to contribute to safe road traffic in which no one is killed or seriously injured. One of the activities conducted as part of this assignment is that the Swedish Transport Administration brings together authorities, organisations and stakeholders who have the opportunity to contribute to this work in a joint action plan. The purpose of the action plan is to strengthen and highlight effective measures implemented by various stakeholders to actively contribute to safe road traffic in the period 2022 to 2025. The plan will also highlight the respon-sibilities of different authorities and stakeholders in the short term, with a focus on a number of priority action areas. The plan is also a tool for the Swedish Transport Administration to be able to lead and monitor the road safety work in an effective and result-oriented manner. The action plan is the second of its kind and applies to the period 2022–2025.]]></description>
      <pubDate>Mon, 10 Jun 2024 14:04:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2388975</guid>
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    <item>
      <title>How is traffic safety affected by changes in traffic speeds following speed limit increases? An evaluation with probe vehicle data</title>
      <link>https://trid.trb.org/View/2100425</link>
      <description><![CDATA[Maximum speed limits continue to be an important policy issue. Research has consistently shown speeds to increase following speed limit increases. These increases have also generally coincided with increases in both the frequency and severity of crashes. However, research has been more limited as to the direct relationship between speed and safety. To this end, the present study evaluates the effects of increasing speed limits on the safety of rural limited access freeways while accounting for contemporaneous changes in the speed profiles of these same roadways. The speed limit increases in Michigan occurred between May 1 and June 12 of 2017, when the maximum speed limits were increased from 70 to 75 mph on approximately 600 miles of freeways. The maximum speed limits for trucks were also increased from 60 to 65 mph on all freeways state-wide at this same time. Speed data were obtained for the Michigan rural freeway network through probe vehicles. These data are merged with pertinent roadway data, as well as police-reported crash data at various levels of injury severity. The impacts of the speed limit increase on safety were evaluated by estimating random effects negative binomial models as part of a case-control before-after study design. The results show that the locations where the speed limits were increased experienced a 5% increase in crashes, while a marginal reduction in crashes was observed where speed limits did not increase. Interestingly, mean speeds were found to be negatively associated with crash frequency, while the standard deviation of speed was found to exhibit a positive relationship. Several site-specific characteristics were also found to be strong predictors of crash frequency. The results provide important insights into the nature of the relationship between speed and safety and will help to guide subsequent speed limit policy decisions.]]></description>
      <pubDate>Mon, 23 Jan 2023 12:29:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2100425</guid>
    </item>
    <item>
      <title>Utredning av mål för ökad cykling i Sverige : ett regeringsuppdrag</title>
      <link>https://trid.trb.org/View/2075213</link>
      <description><![CDATA[Today, there is no defined national target level regarding increase in bicycling in Sweden. VTI received a governmental assignment to define that. The assignment includes a definition of a target structure and suggestion of indicators as well as a system for monitoring. We have gathered information through literature studies, a workshop, a survey as well as through own analyses of data from national travel surveys. We have limited the definition of cycling to include pedal cycle with or without electric assistance. Simply speaking, the rate of bicycling should double by 2035 and, more specifically, we suggest the following targets: Overall objectives: Cycling in Sweden should increase to improve accessibility, strengthen public health, and decrease the climate and environmental impact. Intermediate target 1: The bicycle share of the total number of travellers in Sweden should increase to 20 percent by 2030 and to 26 percent by 2035, without reducing the share of pedestrians or public passenger transports. Intermediate target 2: The bicycle share of the total transport system work in Sweden should increase to 3 percent by 2035, without reducing pedestrians or public passenger transports. Milestone 1: The total share of bicycle travel in Sweden, shorter than 10 km, should increase to 30 percent by 2030 and to 45 percent by 2035, without reducing the share of pedestrians or public passenger transports. Milestone 2: The total share of bicycle travel for primary school children in Sweden should increase to 40 percent by 2030 and to 50 percent by 2035, without reducing the share of pedestrians.  In addition, we have suggested seven indicators with associated measures linked to the targets suggested above. The national travel survey could be used to monitor the targets and the annual report by the National Council of Bicycling could preferably be used for monitoring the indicators.]]></description>
      <pubDate>Fri, 02 Dec 2022 11:41:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2075213</guid>
    </item>
    <item>
      <title>Vikten av att följa upp kommunal upphandling av beläggningsunderhåll</title>
      <link>https://trid.trb.org/View/1948887</link>
      <description><![CDATA[To deepen the understanding of municipal procurements of pavement maintenance and renewal, information on the activities carried out in 2018 and 2019 has been collected from several municipalities. Response rate and access to the requested information is not sufficient to draw firm conclusions. One result of the collection work is therefore that there is still a lack of coherent knowledge about the municipalities' procurements of paving work. Despite this, it is possible to make preliminary recommendations based on available material, the purpose of which is to strengthen the business in the long term.  In part, the proposals are based on work that the research group has carried out over several years on analysing the Swedish Transport Administration's tendering of the same type of activities. While the Swedish Transport Administration procures many individually large pavement projects, the municipalities tender framework agreements that specify several comparatively small measures that may be called off over a multi-year agreement period. The Swedish Transport Administration's orders therefore state what, within an uncertainty interval, is to be carried out, while the municipalities describe activities that may be called off.  In addition to the uncertainty about which jobs a municipality will order, there are also differences in knowledge between the ordering municipality and the companies that submit tenders. While each of Sweden's 290 municipalities carries out a procurement every few years, some dominant contracting companies submit tenders each year for several dozen procurements in different parts of the country. This means that bidders in many cases have a better understanding of which business may be called off than the customer itself has. The company that holds the contract up for re-tendering has a particularly good understanding of the situation in the municipality.]]></description>
      <pubDate>Fri, 06 May 2022 17:07:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/1948887</guid>
    </item>
    <item>
      <title>Kontrakt för underhållsbeläggningar : analyser av produktivitet, effektivitet och kostnadsförändringar mellan avtal och slutkostnader</title>
      <link>https://trid.trb.org/View/1894973</link>
      <description><![CDATA[Every year, the Swedish Transport Administration carries out paving work to maintain an acceptable standard on longer road sections for almost SEK 3 billion. The report summarizes the results of three analyses made of this type of procurement. Both the project cost in the contract between the Swedish Transport Administration and a contractor and the final invoiced cost are treated. The purpose is to identify opportunities to further develop the business's productivity and efficiency. Each percentage point cost savings can free up significant funds to order more maintenance or to transfer to other, more urgent purposes. The first sub-study points to opportunities to streamline the applications of hot coatings. Analysis of the cost of 293 such contracts show that there are strong reasons to consider making the contracts larger than today. The more square meters of asphalt in each contract, the lower the cost per square meter. The second sub-study tries to explain why the final cost is on average 14 percent higher than the cost in the contracts signed, while the third study reports a productivity analysis of the same contracts. Even though several hundred pavement contracts were tendered during the pertinent period, only 91 observations have been available for analysis. The explanation is that it is not possible to link the activities procured with the result of the assignments. This applies to both the costs of the business and the actual amount of work, which may differ from the orders placed.  The final review of the report has also identified shortcomings in the matching between contract and final cost, which means that it is not possible to report any policy conclusions. However, the analyses illustrate how follow-ups can be carried out to deepen the understanding of, among other things, cost deviations.]]></description>
      <pubDate>Wed, 01 Dec 2021 14:50:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1894973</guid>
    </item>
    <item>
      <title>Railway concrete arch bridge over Kalix River at Långforsen : dynamic properties and load-carrying capacity</title>
      <link>https://trid.trb.org/View/1737809</link>
      <description><![CDATA[The concrete arch bridge over Kalix River at Långforsen was built in 1960 and has a mid-span of 89,5 m and a height of 13,7 m. The bridge owner, Trafikverket, wanted to increase its allowable axle load from 225 to 300 kN. Field tests were carried out under service condition and with ambient vibrations. The test results were used to update and validate Finite Element Models. At last, the refined models were used to check the possibility to increase the axle load.   According to earlier assessments, most parts of the bridge is capable of carrying an axle load of 330 kN. The only critical sections are located in the beams carrying the rail on top of the arch in the section where the beams are united with the arch. Here the stresses in the longitudinal bottom reinforcement are slightly too high.   These sections have been studied in a FEM model for different loads and results show maximum strains of about 50·10 -6 corresponding to stresses of only about 10 MPa in the reinforcement in the critical sections. Live load vertical deflections of the crown of the arch is of the order of only ± 6 mm. Dynamic studies have also been made showing that fatigue is no issue. Altogether the studies show that the bridge is able to carry an increased axle load of 300 kN without problems.]]></description>
      <pubDate>Tue, 08 Sep 2020 14:37:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/1737809</guid>
    </item>
    <item>
      <title>Kostnadsöverskridande i Trafikverkets entreprenadkontrakt</title>
      <link>https://trid.trb.org/View/1696276</link>
      <description><![CDATA[The Government has instructed the Swedish Transport Administration (Trafikverket) to promote productivity in the construction industry. VTI assists Trafikverket in this work. In this report, the differences that exist between the price set in the contract between Trafikverket and the construction company that has been commissioned to implement an activity and the final cost of the assignment are reported. 776 contracts relating to contracts in both the road and rail sectors and that comprises both investments and maintenance measures and which cost more than SEK 10 million are included in the material. Statistical tests show, among other things, that the risk of cost overruns is very large, and slightly higher for railway contract (94 per cent probability) than for road contracts (86 per cent). The cost overrun for road contracts (1,20) is significantly lower than for rail contracts (1,32).]]></description>
      <pubDate>Fri, 03 Apr 2020 15:48:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1696276</guid>
    </item>
    <item>
      <title>Analysis of near misses increases road safety</title>
      <link>https://trid.trb.org/View/1577859</link>
      <description><![CDATA[By analyzing images of 'near misses' with specialized video analysis software, we can quickly and accurately detect road safety risks and evaluate measures. This way we can intervene before there are victims. This approach is very logical. In aviation, they do not wait for an airplane to crash. As soon as a near-accident occurs, they analyze the incident in detail to see how such situations can be avoided in the future. Now we also do this with road traffic.]]></description>
      <pubDate>Thu, 17 Jan 2019 09:30:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1577859</guid>
    </item>
    <item>
      <title>Performance based standards for vehicle combinations with weight and/or dimensions exceeding the specified limits in the Directive 96/53/EC: a pre-study for CEDR</title>
      <link>https://trid.trb.org/View/1492554</link>
      <description><![CDATA[This report includes the gathered information in a CEDR pre-study, with the objective to list the relevant safety, manoeuvrability, infrastructure and environment related criteria for longer and/or heavier vehicles. Furthermore, research areas that should be further investigated for development of a harmonized performance based standards for assessing longer and/or heavier vehicles access to a road network, are identified.]]></description>
      <pubDate>Tue, 19 Dec 2017 11:29:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1492554</guid>
    </item>
    <item>
      <title>Increase in number of road deaths in 2015 : Analysis of developments and possible causes.</title>
      <link>https://trid.trb.org/View/1484974</link>
      <description><![CDATA[In 2015, the Netherlands counted 621 road deaths, 51 (9%) more than in 2014. This is significantly more than was expected on the basis of the downward trend. The increase could mainly be observed to commence in the second half of 2015 and, according to the first data of 2016, the rise seems to continue during the initial months of 2016 and to stabilize thereafter. The number of road deaths is also increasing in other countries, but the increase in the Netherlands is relatively large. The Netherlands now occupies the ninth place in the EU ranking of countries with the safest traffic expressed in in road deaths per inhabitant. In 2010, the Netherlands were still in fourth place. Further analysis shows that the number of road deaths has increased especially: a) among car occupants and drivers of mobility scooters and (other) vehicles for the disabled, b) among males of all ages and females between the ages of 50 and 70 years, and c) on national roads and municipal roads. The increase in the number of road deaths may possibly partly be due to an increase in the mobility of inexperienced drivers; to some extent this is a result of economic recovery. Furthermore, the increase of the speed limit (in 2014) to 130 km/h on some motorway sections, the decrease in the number of drivers stopped by the police, and the growing number of mobility scooters may have played a role. For none of the explanations we examined, however, did we find conclusive evidence until now. Finally, there has been an increase in the use of mobile data usage. The extent to which this has also happened in traffic has not been investigated. If this were the case, it could also be a possible explanation.]]></description>
      <pubDate>Thu, 05 Oct 2017 09:37:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1484974</guid>
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    <item>
      <title>Road safety forecasts for 2020 and 2030; Estimate of the expected numbers of fatalities and serious road injuries.</title>
      <link>https://trid.trb.org/View/1484957</link>
      <description><![CDATA[The purpose of this study is to draw up outlooks to examine whether the target of a maximum of 500 fatalities and 10 600 serious road injuries in 2020 is feasible with the current and planned road safety policy. In addition to an outlook for 2020, we have also made on outlook for the number of fatalities and serious road injuries in 2030. The outlooks have been made in two steps: 1. Multiplication of expected risk and expected mobility. The risks in 2020 and 2030 have been estimated based on extrapolation of risk developments in the past. 2. Modification of the forecast in step 1 for new developments, new road safety measures and other changes in road safety policy that affect road safety development.]]></description>
      <pubDate>Thu, 05 Oct 2017 09:36:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1484957</guid>
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