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  • 1.
    Alfredsson, Magnus
    et al.
    NCC.
    Karlsson, Robert
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Hintze, Staffan
    NCC.
    Johansson, Bo
    NCC.
    Lundström, Robert
    NCC.
    Winnerholt, Tomas
    Trafikverket.
    Funktionskriterier för vägkonstruktioner: Förstudie2010Report (Other academic)
    Abstract [sv]

    Det projekt som här rapporteras har som syfte att identifiera och beskriva de svårigheter och möjligheter som totalentreprenader medför, respektive erbjuder, för alla parter. Målet är att utveckla totalentreprenader på ett sådant sätt att branschens effektivitet ökas. Denna rapport är en förstudie där det studerats vilka krav som byggherren ska ställa på utföraren av en vägkonstruktion i en totalentreprenad med funktionsansvar och hur utföraren ska verifiera kraven. Arbetet har genomförts med medlemmar från olika aktörer i branschen och omfattat främst litteraturstudier och intervjuer. Kunskaper och erfarenheter har sammanställts och analyserats för att slutligen kondenseras ned till ett antal förslag till fortsatt arbete.

    Förstudien har pekat ut ett antal områden som viktiga för att påskynda framtida utveckling av totalentreprenader:

    Terminologi – idag råder viss begreppsförvirring

    Analys av funktionella krav i tidigare projekt

    Trafikantkrav

    Miljökrav

    Utveckling av funktionella krav i samverkan

    Väghållarekonomi

    Regelbetingade begränsningar av funktionella krav

    Uppföljning och underlättande av erfarenhetsackumulering

    Implementering av nya mått och mätmetoder

  • 2.
    Andren, Peter
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    An explanation to the VTI FILTER documents2001Report (Other academic)
  • 3.
    Arnberg, Peter W.
    et al.
    Swedish National Road and Transport Research Institute.
    Burke, Michael W.
    Magnusson, Georg
    Swedish National Road and Transport Research Institute.
    Oberholzer, Roger
    Råhs, Knut
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    The Laser RST: Current status1991Report (Other academic)
    Abstract [en]

    Efficient and well-maintained road systems are necessary for the economic well being of any industrialized country. Maintenance and rehabilitation of existing roads have taken priority over new construction in recent years, thus making information about the condition of road surfaces extremely important. Several methods of gathering this information have been developed worldwide; one of them is Laser Road Surface Tester (Laser RST), which was developed in Sweden in 1981. The Laser RST is a laser-based, computer-automated, non-contact road profilometer system with the ability to collect and simultaneously process data about the road surface. Variables measured include rut depth, unevenness, cracking, megatexture, rough macrotexture, fine macrotexture, crossfall, curves, and elapsed distance. Subjective evaluations are also supported, if desired. Eleven laser rangefinders (LRFs), mounted on the front of the Laser RST van, are the primary components of the data collection system. They scan the road with high-speed, high-resolution distance sampling. The signals from the lasers are sent through signal processing cards (SPCs) and then to a computer inside the van for final processing. Data is stored on floppy disk and printed by an on-board printer. The Laser RST is an extremely complex system but it is also a modular one, making troubleshooting and repair relatively easy, inexpensive, and fast. This paper discusses the various modules available. Variables measured are defined and measurement algorithms detailed. The Laser RST system can be customized to meet specific user requirements quickly and easily.

  • 4.
    Arnberg, PW
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, L
    Swedish National Road and Transport Research Institute.
    Nordiska friktionsmätare: En jämförande studie (Friction measuring vehicles in Scandinavia: A comparative study)1983Report (Other academic)
  • 5.
    Arnberg, PW
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, L
    Swedish National Road and Transport Research Institute.
    Nordiska jämnhetsmätare: En jämförande studie (Evenness measuring vehicles used in Scandinavia: A comparative study)1983Report (Other academic)
  • 6.
    Arnberg, PW
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, L
    Swedish National Road and Transport Research Institute.
    Nordiska spårdjupmätare: En jämförande studie (Ruth depth measuring vehicles in Scandinavia: A comparative study)1983Report (Other academic)
  • 7.
    Arvidsson, Anna K.
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Lundberg, Thomas
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Genell, Anders
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Ögren, Mikael
    Göteborgs universitet.
    Åkkvalitet på vinterväg2014Report (Other academic)
    Abstract [en]

    What can be stated in this project is how a winter road is experienced when compared to snow free conditions, primarily with regard to unevenness and noise. Surveys carried out during the project show that it is possible, without too much difficulty, to measure the unevenness of a snow covered road surface. I this report is winter road defined as a snow covered road (around one day after heavy snowfall). Based on survey results, the study shows that the unevenness of section lengths between 0.05 metres and 1.0 metres are most affected by winter road conditions. Unevenness during winter road conditions is approximately five times greater than that experienced during snow free conditions. However, it is impossible to generalise for an entire road network as surface conditions during winter can be extremely variable. It is also possible to see that the surface structure described by the shortest wavelengths investigated, less than 10 millimetres, is smoother on the snow-covered surface. This is one hypothesis and indicates that measurements are reliable. The link between noise and unevenness is related to vehicle speed. The biggest sound difference between winter and summer road conditions, which could be related to the road surface measurements, was at the lower frequency range. Perceived in-car noise levels were between 3 and 6 decibel higher during winter conditions. However, for the higher frequency range the difference in noise levels was opposite - lower levels during winter conditions. A possible explanation for this is that sound may be absorbed by the snow.

  • 8.
    Benbow, Emma
    et al.
    TRL.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Bouteldja, Mohamed
    CETE of Lyon.
    Cerezo, Veronique (Contributor)
    IFSTTAR.
    Spielhofer, Roland (Contributor)
    AIT.
    Toolbox, review of functional triggers: Selection of maintenance candidates2013Report (Other academic)
    Abstract [en]

    ToolBox aims at developing a “concept for proper maintenance planning” to assure the selection of adequate maintenance works (“schemes” or “objects”) to make effective use of the maintenance budget, based on available road condition data, to give minimal negative effects on road users, safety for road workers and the environment. This report covers the first phase of the ToolBox findings and development. In chapter 2 there are a discussion on technical parameters and the use of them. This is followed with a listing of available technical parameters in the partner countries, chapter 4. A state of the art covering how selections of maintenance candidates are done in the respective countries follows including a comprehensive reporting of indicators and parameters available. Finally the chapter 6 covers the selection of models that will be used to evaluate the functional performances decided.

  • 9.
    Berg, Uno
    et al.
    Vägverket.
    Mjörneståhl, Thomas
    Vägverket.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Hedblom, Göran
    Vägverket.
    Sätt vid vägreparation1998Patent (Other (popular science, discussion, etc.))
    Abstract [sv]

    Vid vägreparation användes ett sätt, vid vilket en vägs geometri inmätes och vägen återställes i ett önskat skick genom fräsning respektive utfyllnad av massa. Sättet innefattar kombinationen av stegen att samla in vägdata, att sammanlänka och i en databas inordna inmätta vägdata, att med hjälp av ett datorprogram projektera för återställning av vägens geometri, att skapa digital utdata från projekteringen och förse en elektronisk databärare med dessa data samt att överföra dessa data från den elektroniska databäraren till elektroniska styrandordningar för att automatiskt styra en fräsnings- och utfyllnadsprocess, som återställer vägens geometri.

  • 10.
    Bolling, Anne
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Genell, Anders
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Lidström, Mats
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Nordmark, Staffan
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Palmqvist, Göran
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Sehammar, Håkan
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ögren, Mikael
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    SHAKE - an approach for realistic simulation of rough roads in a moving base driving simulator2010In: Trends in driving simulation design and experiments: proceedings of the driving simulation conference Europe 2010, Arcueil: Institut national de recherche sur les transports et leur securite, INRETS , 2010, p. 135-143Conference paper (Refereed)
    Abstract [en]

    With today’s advanced measurement equipment for measuring roads, it is possible to measure road geometry at high precision within a large span of wavelengths. Detailed information about the roads longitudinal and lateral profile, including macro texture, would in theory be sufficient for a realistic reproduction of road induced vibration and noise in a driving simulator. Especially, it would be possible to create a direct connection between the visual information of the road condition and the ride experience, which would increase the level of realism in the simulation. VTI has during three years performed an internal project called SHAKE with the aim to develop and implement models in VTI driving simulator III that use measured road data for generating realistic vibrations and audible road noise connected to the visual impression presented on the projection screen. This has indeed resulted in an more realistic driving experience, and a validation study with test persons driving both in the simulator and in the field has been undertaken. The OpenDRIVE standard is used as a framework for describing the road properties (e.g. visual, vibrations and noise). For this purpose some augumentations to the OpenDRIVE standard had to be made. This paper describes the technical implementations in the driving simulator, along with results from test drives on the implemented road sections

  • 11.
    Bolling, Anne
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Lidström, Mats
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Nordmark, Staffan
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Sehammar, Håkan
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Genell, Anders
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Sörensen, Gunilla
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Improving the realism in the VTI driving simulators: Shake final report2012Report (Other academic)
    Abstract [en]

    The Swedish Road and Transport Research Institute (VTI) has three advanced moving base driving simulators. The aim of this project was to develop and implement new models concerning vibration, noise and graphics in order to improve the realism in the simulators. Moreover, a validation study was to be conducted.

    Within the frame of the project the following were achieved:

    • improvement of the tyre/road vibration models,
    • •improvement of the motion system by changing the rotation centre,
    • •improvement of the noise module facilitating reproduction of noise from tyre/road,
    • •synchronization of the impressions from graphics, noise and vibrations caused by the road surface.

    The validity of the models was tested in the VTI Simulator III. Statistical testing of differences between the car and the simulator indicated absolute validity for the subjective ratings of evenness and noise level and the objective measure speed, with the exception of areas surrounding speed limit signs where only relative validity was found. Relative validity was also indicated for the variable overall comfort. The results from the different validations show that the improvements have been successful and the driver in the simulator can now see, hear and feel the sensation of any road surface irregularities exactly when the wheels hit that part of the road. However, several improvements in the simulator models can still be desired.

  • 12.
    Bolling, Anne
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Wågberg, Lars-Göran
    Swedish National Road and Transport Research Institute.
    FORMAT - Optimerat vägunderhåll: del I: Praktisk guide för optimerat underhåll, del II: Teknisk slutrapport2006Report (Other academic)
    Abstract [sv]

    EU-projektet FORMAT (Fully Optimised Road Maintenance) ingick i EU:s femte ramprogram; "Task 2.2.2/11, Road infrastructure pavement maintenance management" under "Uthållig rörlighet och förändring". Projektet startade den 1 februari 2002 och pågick i tre år.

    Den översättning och sammanfattning som redovisas i detta VTI notat har delats upp i två delar; Praktisk guide för optimerat vägunderhåll och Teknisk slutrapport.

    FORMAT-projektet hade följande tekniska och vetenskapliga målsättningar: - Ta fram bättre fungerande, innovativa underhållsåtgärder och metoder som minskar trafikstörningar, i form av köbildning och förbättrad säkerhet, i samband med vägarbeten - Utveckla en heltäckande "cost-benefit" analys som tar hänsyn till alla viktiga aspekter av vägunderhåll, inklusive trafikantkostnader - Utveckla strategier, för säkerheten vid vägarbeten, som omfattar utformningen av vägavstängningar och tidpunkten för åtgärdens genomförande på ett sådant sätt att säkerheten för trafikanter och vägarbetare maximeras - Föreslå metoder, tillvägagångssätt och utrustning för mätning av vägars tillstånd i normal körhastighet för att minimera antalet störande vägavstängningar som krävs för insamling av tillståndsdata.

  • 13.
    Edvardsson, Karin
    et al.
    Transportstyrelsen.
    Lundberg, Thomas
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Objektiv mätmetod för tillståndsbedömning av grusväglag2015Report (Other academic)
    Abstract [en]

    Condition ratings on the gravel road network are of today made subjectively according to the Swedish Transport Administration’s current method description. This project aims to develop a reliable, objective and mobile methodology for continuous measurement of the road surface condition parameters: evenness, loose gravel, dust and cross fall on gravel roads. It also aims to recommend an objective inventory method for evaluating the drainage condition of a gravel road construction. The result shows that the objective condition indicators which best seem to describe the requested functionality on gravel roads are the acceleration measured using a smartphone application as well as macro texture expressed as the mean profile depth MPD and the average laser pulse reflection over the road cross section measured with a laser equipped measurement vehicle. As an objective inventory method for evaluating the drainage condition of a gravel road, measurements of ditches to ensure satisfactory ditch depth, measurements of cross fall, measurements of support strips to ensure absence of road edge overhang that prevent water runoff from the road, and measurements of periodic and/or rapidly proliferating roughness are proposed. Since gravel road condition is rapidly changing during the season, a quick and simplified version of road surface measurements is required if it should be cost effective with these types of measurements on the gravel road network. Using a smartphone with an application for measurements of evenness is a simple and cost effective way to generate up-to-date condition data for the gravel road network. The application could be supplemented with a button to allow the public to report and mark out damages to the road or be connected to the contractor’s GPS-enabled reporting system, used to mark special points of interest, such as sites for frost heave or erosion.

  • 14.
    Hedström, Ragnar
    et al.
    Swedish National Road and Transport Research Institute.
    Ihs, Anita
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Funktionsupphandling av väg- och banhållning: problem och möjligheter2005Report (Other academic)
    Abstract [sv]

    The present project has been carried out within the framework of the subject

    "Competitive procurement in the transport sector". Owing to the increase in

    the costs of infrastructure maintenance on roads and railways in recent

    years, there is greater interest in developing new forms of contract. The

    intention of the ongoing process concerning competitive and performance

    oriented procurement is to create the conditions for more effective

    infrastructure maintenance activity. The problem in performance oriented

    procurement is to define relevant performance requirements which are clearly

    linked to the effects for the final users. This requires the performance

    variables to be measured and evaluated with respect to both the division of

    responsibility between contractor and client and also the perspective of the

    travelling public. In the project, a study is made of the possibility of

    using planning models such as the World Bank HDM-4 or other operationally

    available models/tools in the road sector (e.g. the Swedish Road

    Administration's PMS) in pricing measurable "final results" in conjunction

    with performance oriented procurement. One conclusion which is generally

    valid for both HDM-4 and PMS is that the traffic effect models must be

    complemented before they can be fully used for the purpose of pricing

    measurable "final results" in contracts based on performance oriented

    tendering. On the rail side, there is no counterpart to HDM-4 or PMS. The

    performance variables identified during performance oriented procurements for

    rail infrastructure maintenance are train delays, track bed condition (via Q

    and K indices), defect reports and inspection comments. These performance

    variables can be measured, monitored and evaluated in economic terms in the

    relationship between client/contractor and, to some extent, also in relation

    to the final customer, i.e. the travelling public. There is however no model

    available which gives an overall description of the effects of these

    performance variables and the economic consequences which these, in turn,

    have for Banverket and/or society at large. Even though a lot is known with

    regard to performance oriented procurement of infrastructure maintenance,

    several issues remain to be solved in both the road and rail sectors. It is

    therefore essential that continuity for further research should be created in

    this field.

  • 15.
    Ihs, Anita
    et al.
    Swedish National Road and Transport Research Institute.
    Andren, Peter
    Swedish National Road and Transport Research Institute.
    Mård Berggren, Selina
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Utformning av väg och vägyta för säkerhet, komfort och hälsa: en förstudie2006Report (Other academic)
    Abstract [sv]

    During summer 2002 a special directive about employees' health and security at exposure to risks due to vibrations during work, also called "Physical agents vibration directive" (Directive 2002/44/EC), was adopted by the EC. The member states had until July 6th 2005 to transfer the directive into the national legislation. Certainly the condition of parts of the road network can be such that the vibration levels that professional drivers are exposed to exceed the limits that are given in the vibration directive. VTI has therefore been commissioned to carry out a pilot study including a survey of the responsibility of the Swedish Road Administration (SRA) as well as the interpretation of the directive made by the Swedish Work Environment Authority, but also to study how different designs of the road's longitudinal profile may give rise to vibrations that are harmful or uncomfortable to humans. The present pilot study has included a literature survey concerning vibrations and their influence on humans with particular reference to roads and their design, demonstration measurements of road geometry and vibrations and analyses of these with regard to the directive as well as discussions on suitable measures for health risks or discomfort during travel on road.

  • 16.
    Ihs, Anita
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Gustafsson, Mika
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Wiklund, Mats
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Road user effect models: the influence of rut depth on traffic safety2011Report (Other academic)
    Abstract [en]

    There are currently no satisfactory effect models for calculating the consequences and costs for road users of different maintenance strategies. The main problems identified by the Transport/Road Administrations in Finland, Sweden, Norway and Estonia, are the relationship between road surface condition and accidents, the effect of the most important state parameter rut depth on road user costs, as well as the role of road-user costs/effects of a road network that is mostly in good condition. These are problems that must be resolved in order to better justify budget allocation for road maintenance. VTI has therefore on commission by the Finnish Transport Administration and with funding from the other Transport/Road Administrations conducted a study to determine the influence of rut depth effects on the accident risk of road users. Separate analyses were made of data from Sweden, Finland and Norway, respectively. It was assumed that the accident risk also depends on other road condition variables, such as longitudinal unevenness, texture, cross slope, geographic location (country), vehicle flow, climate, weather, etc. A model approach was chosen that could address the impact of all these other road condition variables, and the possible interactions between them, on the accident risk. It was assumed that the relationship between accident risk and rut depth is not necessarily a linear function, why rut depth was divided into several categories. It was also agreed that separate equations should be derived for different speed and AADT (Annual average daily traffic) classes. Rut depth categories, as well as speed and AADT classes were chosen to match each country's strategies for maintenance. The overall conclusion of the analysis is that the data does not support any general rules for a maintenance scheme. There are no results to show that deeper ruts generally tend to increase the accident risk. Nor are there results that show that ruts have the same influence on the accident risk for different AADT classes at a given speed or vice versa. There seems to be at increased risk for ruts ? about 15 mm in the highest speed class, but the results differ between AADT classes and are not similar in adjacent speed classes, making the results difficult to understand and less useful to specify the rules for maintenance. For the Norwegian data this trend can not be seen in the highest speed class (> = 90 km/h), but then this speed class differs from the Swedish and Finnish highest speed classes (> = 110 km/h roads and motorways, respectively).

  • 17.
    Ihs, Anita
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Blomqvist, Göran
    Swedish National Road and Transport Research Institute.
    Grudemo, Stefan
    Swedish National Road and Transport Research Institute.
    Planning of the road transport system development: A literature review2003Report (Other academic)
    Abstract [sv]

    A large number of persons are killed or seriously injured in road traffic

    every year, and this is not least a great public health problem. The

    development of different traffic safety measures is proceeding rapidly, and

    it is of importance that the knowledge is spread and applied. In order to

    gain information on the state of the art within the traffic safety area the

    Swedish National Road Administration (Vägverket) has commissioned

    universities and research institutes to carry out a number of literature

    surveys covering different parts of the area. This literature survey concerns

    the planning of the road transport system development. Since this is a very

    extensive area to cover, certain limitations have been made. The focus is

    primarily on investigating the concepts of trafficability, accessibility,

    environmental impact and traffic safety but also measures and methods used

    for describing the influence of road surface condition on these.

  • 18.
    Kuttah, Dina K
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Research And Development Strategy Of Vti2013Conference paper (Other (popular science, discussion, etc.))
  • 19.
    Lang, Johan
    et al.
    WSP Samhällsbyggnad.
    Berglöf, Jan
    WSP Analys & Strategi.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Förslag till index för att beskriva belagda vägytors tillstånd2012Report (Other academic)
    Abstract [sv]

    Historiskt har tillståndet på det svenska statliga vägnätet redovisats med mått på ojämnheter i tvär- och längsled (Spårdjup max respektive IRI (International Roughness Index). Successivt har dock nya mått och flera mått utvecklats för att beskriva tillståndet, samtidigt som detaljeringsgraden ökat. Det innebär att komplexiteten ökar och att det blir svårare att få en överskådlig och lättfattlig bild av tillståndet. Graden av detalj beror ju på till vilket ändamål beskrivningen ska användas till. Det finns ett behov att kunna redovisa tillståndet på ett överskådligt sätt. Syftet med detta projekt är att med hjälp av index beskriva vägnätets tillstånd på ett enkelt och översiktlig sätt.

  • 20.
    Loukopoulos, Peter
    et al.
    Swedish National Road and Transport Research Institute.
    Forsberg, Inger
    Swedish National Road and Transport Research Institute.
    Ihs, Anita
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Trafikanternas krav på vägars tillstånd: en fokusgruppsstudie2008Report (Other academic)
    Abstract [en]

    Part of the project "Trafikanters krav på vägars tillstånd" (Motorists' requirements on the condition of road surfaces) consists of a focus group study, in which the aim is to investigate motorists' expectations regarding road-surface conditions and the factors influencing these expectations. The roads examined in this study are those belonging to the state's road network, primarily outside urban areas. Another aim is to see which names and terms motorists use to describe various road-surface problems. The results will be used to aid the design of a questionnaire as part of a later phase of the project. Six focus groups were conducted and, in total, 42 people participated - 15 private motorists (10 males and 5 females) and 27 professional motorists (15 bus drivers and 12 lorry drivers, all male). Two focus groups consisted of private motorists, one group with younger participants and another with older participants, two groups consisted of bus drivers, and two groups of lorry drivers. All participants had experienced a variety of road and driving stretches (e.g., motorways, urban driving, and long-distance driving).

  • 21.
    Lundberg, Thomas
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Andrén, Peter
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Wahlman, Thomas
    Ramböll.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ekdahl, Peter
    Ramböll.
    New technology for road surface measurement: transverse profile and rut depth2018Report (Other academic)
    Abstract [en]

    The condition of the national coated road network is measured annually in Sweden and Finland. The measuring technology has been unchanged over a long period of time, which has its benefits. As the measurements are performed using the same technology, trends and measurement series are retained without any disruption. In addition, the technology currently used is reliable and can be procured at a price level that has fallen rather than risen over the years. The principal area of use for condition measurement is to provide maintenance work with an objective basis for the planning of surfacing, but when it is found that current objective condition data can only explain between 40 and 75 percent (depending on class of traffic) of the action actually taken on the road network, consideration must be given to whether new condition data need to be added. The information that is lacking is thought to be information on surface damage and cracks. This requires new measuring technology.

    If new technology will be adopted, for the collection of condition data, the dependability of the basic measured quantities must be ensured before new options and measured quantities are examined. This study is therefore focused only on transverse-profile measurement and measures of unevenness in the transverse direction (rut depth and ridge height).

    The study has examined two of the leading new technologies that operate with scanning lasers, LCMS from Pavemetrics and PPF from Fraunhofer. The outcome of the study shows that the technology is good, and that accuracy and repeatability are comparable to the present-day point-laser systems. It is also deemed possible to retain criteria and requirements for the procurement of measurement services when the new technology is used.

  • 22.
    Lundberg, Thomas
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Andrén, Peter
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Wahlman, Thomas
    Ramböll.
    Eriksson, Olle
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ekdahl, Peter
    Ramböll.
    Ny teknik för vägytemätning: tvärprofil och spårdjup2018Report (Other academic)
    Abstract [en]

    The condition of the national coated road network is measured annually in Sweden and Finland. The measuring technology has been unchanged over a long period of time, which has its benefits. As the measurements are performed using the same technology, trends and measurement series are retained without any disruption. In addition, the technology currently used is reliable and can be procured at a price level that has fallen rather than risen over the years. The principal area of use for condition measurement is to provide maintenance work with an objective basis for the planning of surfacing, but when it is found that current objective condition data can only explain between 40 and 75 percent (depending on class of traffic) of the action actually taken on the road network, consideration must be given to whether new condition data need to be added. The information that is lacking is thought to be information on surface damage and cracks. This requires new measuring technology.

    If new technology will be adopted, for the collection of condition data, the dependability of the basic measured quantities must be ensured before new options and measured quantities are examined. This study is therefore focused only on transverse-profile measurement and measures of unevenness in the transverse direction (rut depth and ridge height).

    The study has examined two of the leading new technologies that operate with scanning lasers, LCMS from Pavemetrics and PPF from Fraunhofer. The outcome of the study shows that the technology is good, and that accuracy and repeatability are comparable to the present-day point-laser systems. It is also deemed possible to retain criteria and requirements for the procurement of measurement services when the new technology is used

  • 23.
    Lundberg, Thomas
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ekblad, Jonas
    NCC Roads.
    Göransson, Nils-Gunnar
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Arvidsson, Anna K.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Makrotexturens möjlighet att identifiera låg friktion: tillståndsmätning av vägytan2015Report (Other academic)
    Abstract [en]

    The Swedish Transport Administration want to describe the friction condition of the entire national road network. A nationwide friction measurement is practically difficult to manage and very costly, while we are already measuring road surface macrotexture. In this project, we test whether the macro texture (MPD, Mean Profile Depth) can be used to describe the friction condition of the road network. We have not been able to show this correlation but we present other interesting findings that give a piece of the puzzle for the Swedish Transport Administration how they can and should deal with the friction issue. We see, among other things, that the risk of low friction is greater on road sections with low MPD values and especially on roads with surface dressing that has bleeding patches. Furthermore, we describe the friction risks involved with different coatings and how these might be handled.

  • 24.
    Lundberg, Thomas
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Qualification of road surface monitoring services in Sweden, 1996-20002004Report (Other academic)
    Abstract [en]

    The aim of this report is to summarise and report the experience acquired from the comparative surveys conducted in 1996, 1997 and 2000 in connection with the Swedish National Road Administration's procurement of road surface survey services. The main conclusions concerning the survey results are presented. Further, the report also contains findings related to the development of a method that was a prerequisite for the work. Basic background information is also given about the parameters and survey methods used. In the section entitled "Grey zone", a few grounds on which survey vehicles can be used to verify contracted surfacing works are presented on the basis of the survey results obtained.

  • 25.
    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.
    The influence of lateral position when measuring road surface characteristic data: introductory study2012Report (Other academic)
    Abstract [en]

    In conjunction with development of rolling resistance models it has been brought up to date that the knowledge of the size of variation of road surface characteristics data across a road section is not well known.

    In a rather limited VTI study it was shown that the MPD (Mean Profile Index) level varies with lateral position, especially on smaller roads which are often used as test sections in model development. Also other road surface data such as IRI (International Roughness Index) and megatexture vary. Another conclusion is that data used for model development should be collected. The study is a part of the MIRIAM project.

  • 26.
    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.
    Svenska vägtillståndsmått, då, nu och i morgon: del 3: i morgon – år 2010 och framåt2015Report (Other academic)
    Abstract [en]

    On behalf of the Swedish Road Transport Administration, VTI has developed and proposed new indices of road surface measurement that better describe damaged or badly constructed road sections. The indices have been developed using data that is already collected during the regular road network surveys. The new indices can be used to describe road network conditions and changes during operation. To complement current indices, the report proposes four new indices and recommends changes in the use and/or calculation of two others. The main development principle was to use existing surveyed data and create either a new single index or indices based on a combination of other existing indices. The new indices must also correspond to a specific effect or property, for example safety risk. In connection with the development, thresholds for maintenance standards have also been suggested. The indices developed in this final phase of the project "New Indices of Measurement” that can complement existing indices are: • surface damage (small and large). • cross fall variation. • local unevenness (new definition). • surface water area. • edge depth (new definition). • IRI left (compliment to IRI right). This report describes new road condition indicators used in the period 2010 och onwards. Two earlier reports in this series describes indicators used in the period 1987–2005 (R717, 2013) respectively year 2006–2009 (R718, 2011).

  • 27.
    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.

  • 28.
    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.
    Gustafsson, Mika
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ihs, Anita
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Vägytans makrotextur och dess variation: vägytemätning med mätbil2011Report (Other academic)
    Abstract [en]

    Early fault detection, particularly at construction stage, can result in substantial savings for the Swedish Transport Administration. A contributing element to these savings is to have a homogeneous bituminous surface structure. For example, load changes, at low temperatures, can create a heterogeneous surface structure that gives rise to premature maintenance needs. Established methods or macro texture measurement models are not currently available in Sweden. Other countries have made advances in this field but they have not yet had an impact in Sweden.

    An objective of this project is to maximize the possible use of existing measurement technology, quality and techniques associated with road surface measurement carried out by survey vehicles. In some cases, after a new surface has been laid, ‘object measurement’ is carried out by a survey vehicle. These measurements can be used to approve the surfacing contractor's performance in terms of longitudinal and transverse smoothness. A similar method, with specified values for homogeneous surface structures, will be developed in this project. An object is designed to provide a safe road surface throughout its design life expectancy. In order to be able to achieve this, it is important to discover surface shortcomings such as material separation. Four different models were tested in the project - all of which show promising results. Generally, all the models were able to identify the worst test surface. However, the actual "failed" road surface length of the object varied between models. This, above all, is a question of calibrating the models' limits. However, there is also potential to improve the model itself.

  • 29.
    Magnusson, Georg
    et al.
    Swedish National Road and Transport Research Institute.
    Dahlstedt, Sven
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Mätning av vägytans longitudinella jämnhet: – metoder och nödvändig noggrannhet2002Report (Other academic)
    Abstract [sv]

    The Swedish National Road Administration's (Vägverket) procurement for road

    building projects is shifting increasingly towards

    function-based contracts. This means that the requirements on the evenness of

    a road surface must

    reflect the capacity of the surface to serve the road user satisfactorily and

    with minimal impact on

    the local environment, while minimising costs for the road authority. In

    general, there are virtually

    no evenness indexes describing the serviceability of a road surface in these

    respects. It is probable

    that the connection between road evenness and such indexes is of varying

    strength, which means

    that the requirements on accuracy in road surface measurement are dependent

    on the purpose of the

    measurements. However, earlier research into road user, road authority and

    environmental effects

    of road surface characteristics has paid no attention to the issue of what

    accuracy is required in

    each case in order to study road surface characteristics and enable the

    prediction of such effects.

    Decisions regarding the accuracy required in measuring road profiles demand

    access to a

    relatively large sample of realistic road profiles with different evenness

    levels and spectral

    composition. Therefore, it was necessary to create a database within the

    project containing road

    profiles that had been measured with a known high level of accuracy.

    Established relations

    between road evenness and various related factors are largely based on

    measurements from

    existing road profilometers of the high-speed type. In order to estimate the

    value of these relations,

    it was therefore necessary to investigate whether existing profilometers

    offer the measuring

    accuracy required for these purposes. Data obtained from known road profiles

    with the aid of such

    equipment were thus collected.

  • 30.
    Nilsson, Jan-Eric
    et al.
    Swedish National Road and Transport Research Institute.
    Ihs, Anita
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Wågberg, Lars-Göran
    Swedish National Road and Transport Research Institute.
    Funktionsupphandling: sammanfattning av kunskapsläge och rekommendationer för fortsatt forskning2006Report (Other academic)
    Abstract [sv]

    The Swedish concept "procurement of function" corresponds to performance contracting in Anglo-Saxon countries. The substance is that principal and agent signs a contract over the construction and maintenance of a specific project based on the services provided to future users, i.e. based on performance of the asset. This is in contrast with contracting base on technical qualities of the new road. VTI has reserved funds to provide an overview of current knowledge in this context. Four separate contributions, together with a short summary, are included in this report. One conclusion is that the experiences of this contractual form are much larger in other countries than in Sweden. We therefore have a lot to learn, not least from our closest neighbours Finland and Norway. International experiences indicate a large and growing interest in this form of contracting and provides reason for further development. A second conclusion is that Sweden in general and VTI in particular has important information of direct relevance for the development of efficient performance contracts. This knowledge must, however, typically be structured and organised along other lines than when the original research was undertaken. The institute should therefore seek to adapt the collection of information of relevance for performance contracts so that it fits in to this new framework. This includes issues such as the measurement of road surface quality and assessment of the additional costs for providing better surface quality on the one hand and the user benefits of improved quality on the other.

  • 31.
    Niska, Anna
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Mobilapp för mätning av cykelvägars ojämnheter: en studie av möjligheterna2014Report (Other academic)
    Abstract [en]

    In this study the researchers have investigated the possibilities of measuring irregularities on a cycle path with the aid of the accelerometers in smartphones. Smoothness is an important parameter for describing the functional state of the cycle infrastructure. Measurements and methods of measurement objectively describing functional status are needed so that interaction effects can be identified and functional requirements which take the needs and circumstances of cyclists into account can be defined. Objective measurements of functional status can also be fed into maintenance planning, choice of action and monitoring of action outcomes. Using mainly field studies, we have evaluated a mobile app developed at VTI for measuring surface smoothness. Cyclists have collected quantitative data with the VTI app, using a phone fitted to the handlebars and were also asked to rate their subjective perception of comfort when riding over different surfaces. The results show that the acceleration values recorded with the VTI app vary from one measurement to another but that it is possible, on the basis of these values, to distinguish between surfaces of differing quality. However, the observed acceleration values hinge on the mobile phone used, the cyclist’s lateral positioning and speed etc. The results of measurements with the VTI app tally quite well with the cyclists’ subjective ratings of the ride quality of different surfaces. This project presents results from the project CyCity Theme C - Dp10 and a project from the Swedish Road Administration, Evaluation of ways to monitor cycle path condition with a smartphone. CyCity Theme C - Dp10 is part of the Vinnova-funded research programme CyCity. One conclusion is that there are good prospects of supplementing the BikeRoute cycle planning tool, devised within CyCity, by gathering data with the VTI app describing the smoothness of cycle paths using the VTI app. The VTI app is not yet applicable for crowdsoursing, but valuable when gathering data under controlled settings and is worth developing further for measuring the status of cycle path surfacing.

  • 32.
    Niska, Anna
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Mätmetoder för tillståndsbedömning av cykelvägar: en kunskapsöversikt2007Report (Other academic)
    Abstract [sv]

    This is a review of existing knowledge in indices and measuring methods for assessing the condition of cycle paths. The review is to serve as the basis for any further work that VTI may carry out in this area. The condition of the road surface is of significant importance for the comfort and accident risk of cyclists. Objective methods are needed to measure the condition of cycle paths so that the effects of operational and maintenance measures may be studied, and to set up measurable performance requirements. Presently, such methods are not used on cycle paths in Sweden. Instead, manual damage surveys and visual inspections are made; these may provide a lot of detailed information but are subjective and time consuming. Several methods for condition assessment of motor roads do exist, but they do not satisfactorily reflect the impression of cyclists regarding the road surface, and are often made using equipment that can damage the cycle path. There are also a number of hand drawn, lightweight equipments available, but they are both time and resource consuming.

  • 33.
    Niska, Anna
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Gustafsson, Mika
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Jämnhetsmätning på cykelvägar: utveckling och test av metod för att bedöma cyklisters åkkvalitet baserat på cykelvägens längsprofil2011Report (Other academic)
    Abstract [en]

    Condition assessment of cycle paths is important for planning and prioritising maintenance measures. In order to promote cycling the assessment methods need to be related to cyclists' needs and not only to the technical condition of the cycle path. Objective measuring methods are essential in order for measurable performance requirements to be specified regarding the needs of the cyclists. For the riding comfort of cyclists, the surface evenness of the cycle paths is probably the parameter that has the greatest importance.

    In this study, a method for measuring the surface evenness of cycle paths has been tested and evaluated. The method is based on measurement of the cycle path's longitudinal profile using laser sensors. Several measurements were made on cycle paths in Malmö. In order to associate the measurements with the riding quality perceived by cyclists, cyclists were asked to assess their impression of the surface of some test sections of variable quality. There were large individual differences in the assessments of the cyclists, but it was nonetheless possible to make a distinction between assessments of the different sections.

    In order to describe surface evenness a straight edge model was used. Analyses showed that 0.5 m was the length of the straight edge that yielded the best correlation between measured value and the assessment of the cyclists. Because of the limitations in the measuring method used, only unevenness with wavelengths varying from approximately 20 to 50 cm were assessed. It is probable that unevenness of smaller wavelength also have great significance for the cyclists' riding quality, which implies that macro and mega textures should also be measured.

  • 34.
    Nitsche, Philippe
    et al.
    AIT Austrian Institute of Technology.
    Van Geem, Carl
    Belgian Road Research Centre (BRRC).
    Stütz, Rainer
    AIT Austrian Institute of Technology.
    Mocanu, Isabela
    AIT Austrian Institute of Technology.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Monitoring ride quality on roads with existing sensors in passenger cars2014Conference paper (Other academic)
  • 35.
    Offrell, Petra
    et al.
    Swedish National Road and Transport Research Institute.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Crack measures and reference systems for a harmonised crack data collection using automatic systems2005Report (Other academic)
    Abstract [sv]

    The increased use of automatic systems for crack data collection has created some interesting questions about suitable crack measures. Traditional measures are sometimes unsuitable or even impossible to obtain using automatic data collection. However, the efficient and fast automatic crack data collection has also increased the numbers of possible measures that can be calculated from the results. Another issue originated from the need of conformance within Europe as well as globally is the necessity of an acceptable reference system that can be used to compare and accept different systems. This paper discusses different cracks measures and possible reference systems. The need for different measures, based on the level of which the application is intended to, is also discussed.

  • 36.
    Offrell, Petra
    et al.
    Ramboll RST.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Magnusson, Rolf
    Högskolan Dalarna.
    Repeatability in crack data collection on flexible pavements: Comparision between surveys using video cameras, laser cameras, and a simplified manual survey2005In: Journal of transportation engineering, ISSN 0733-947X, E-ISSN 1943-5436, Vol. 131, no 7, p. 552-562Article in journal (Refereed)
    Abstract [en]

    Crack data can be collected using manual or automatic surveys. Traditionally, manual methods are used, and they are still the most common. Changing into automatic systems will enhance the efficiency of data collection as well as the objectivity. In this study the repeatability of an automatic crack data collection system using video images was evaluated. Ten repetitive measurements were made on a 10-km-long road section. Cracking was measured using six laser cameras attached to the same vehicle.

    The results from the two methods were compared. Simultaneously, a simplified manual windshield survey was conducted by three different persons, and the repeatability obtained was used for comparison with the repeatability established using the image and laser method, respectively. The correlation between repeated measurements using the two automatic systems was high, while the repeatability for the manual, subjective method was low. Suitable measures for crack characterization are discussed.

  • 37.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Data quality management related to road infrastructure condition and safety2016Conference paper (Refereed)
    Abstract [en]

    When doing safety and accident studies related to road surface characteristics the quality of the used data are of extreme importance. The definition, the techniques and strategy of collection of both condition as accident data can differ a lot between and within countries. An example of such confusion is the data considering pavement friction and skid resistance. In Europe currently more than 15 measuring devices for skid resistance are covered in the CEN standards. The availability of enough friction is the most essential road characteristic for safety issues. Other examples is the use of expressions of road condition such as rut depth. No standard exist and different calculations are used implying that they need careful consideration before exchange of accident analysis results are done. Most road surface indicators are developed for indication of road wear, not accident analysis. The Road Administration in Sweden have paid attention to this and made a number of actions to improve the quality of data. There are many quality aspects on data and data collection such as reliability, robustness, suitability for the purpose (relevant), performance, safe to collect, easy to maintain and costs. This presentation will present some actions and quality improvements for data and data collection that has been done in Sweden.

  • 38.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Ett system för inmätning och underhållsprojektering av vägar1992Report (Other (popular science, discussion, etc.))
  • 39.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Fill and mill: A method of calculating adjustment volumes with the laser RST1994Report (Other academic)
  • 40.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Friction requirements on roads, paths and cycleways in summer road condition in Sweden: a pilot study2018Conference paper (Refereed)
    Abstract [en]

    The Swedish Transport Agency is working to achieve good accessibility, high quality, secure andenvironmentally aware rail, air, sea and road transport. They have overall responsibility for drawing upregulations. Recently they commissioned VTI to review and give recommendations on friction/skidresistance measurements in Sweden (dry road condition). Up to now, no common rules for frictiontesting exist for all roads and paths. The present rules only applies to governmental owned andmaintained road. The new challenge is to include urban roads, cycleways and walking paths as well. Wehave studied used methods and rules, mainly in the Nordic countries and especially looked atmotivations of requirements, measured friction levels and the desired thresholds. Finally, after analysisof the review results we have recommended methods and assessed risks of the suggestions. The reviewhave resulted in a set of recommendations such as what measurement methods to use, practical thresholdtriggers but also what needs to be further investigated. This paper will present the results from thereview.

  • 41.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    History of Road Profile Measurements and Current Standards in Road Surface Characteristics2015Conference paper (Other (popular science, discussion, etc.))
  • 42.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Kvalitet hos vägytedata2015In: Transportforum 2015, 2015Conference paper (Other academic)
  • 43.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Overall quality management of road condition monitoring: a case study2015Conference paper (Other academic)
  • 44.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Quality management of road monitoring data2014Conference paper (Other academic)
  • 45.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Quality management of road monitoring data2014Conference paper (Other academic)
  • 46.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Road performance monitoring: A glimpse into the future2007Conference paper (Other academic)
  • 47.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Road profile data quality control: The Swedish model2009Conference paper (Other (popular science, discussion, etc.))
  • 48.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    Road surface measuring in Sweden or Europe?2005In: Reprint from 6th International Conference on Managing Pavements 19–24 October 2004: Brisbane Convention & Exhibition Centre, Queensland Australia, Linköping: Statens väg- och transportforskningsinstitut, 2005, p. 1-10Conference paper (Other academic)
    Abstract [sv]

    Since 1987, road surface condition data has been collected in an organized way in Sweden. In the past, the data collection was done within the Road Administration. Today this is done by private companies, on commercial basis following the result of a procurement process. The improvement and development of equipment is mainly to be done by the commercial actors. There is a need for a European or worldwide standard. This report will address how to choose equipment and operator with respect to requirements such as necessary accuracy and data quality and suggestions of possible future measures and equipment as well as a proposal for a worldwide test procedure standard.

  • 49.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    RST-bil för forskningsändamål1989Report (Other academic)
  • 50.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute.
    RST-mätningar på grusväg, uppföljning av vägytans kvalitet: presenterat på VTI och KFBs transportdagar 13-14 januari 19981998Report (Other academic)
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