Publikasjoner
Endre søk
Begrens søket
1234567 1 - 50 of 1344
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1. Abed, Ahmed
    et al.
    Bizarro, Diana Eliza Godoi
    Neves, Luis
    Parry, Tony
    Keijzer, Elisabeth
    Kalman, Björn
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Carrion, Ana Jimenez Del Barco
    Lo Presti, Davide
    Mantalovas, Konstantinos
    Buttitta, Gabriella
    Airey, Gordon
    Uncertainty analysis of life cycle assessment of asphalt surfacingsInngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Life Cycle Assessment (LCA) of asphalt pavements are associated with significant uncertainty resulting from variability in the quantity and impact of individual components, the quality of data for each component, and variability of asphalt durability. This study presents a framework to quantify and incorporate the uncertainty of LCA and asphalt durability data into LCA of asphalt surfacings. The suggested framework includes: estimating the uncertainty of asphalt production processes by the pedigree matrix method, conducting a deterministic LCA, applying Monte Carlo Simulation (MCS) to estimate the probability density functions (PDFs) of the considered impacts using the uncertainty data, deterministic solution, and asphalt durability. This framework was applied to six asphalt mixtures; the results show that there is significant uncertainty in the processes that contribute to the environmental impacts. They also showed that considering asphalt durability and its uncertainty is critical and can significantly change the results and interpretation of LCA.

  • 2.
    Afridi, Muhammad Amjad
    et al.
    KTH, Sverige.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA. KTH, Sverige.
    Sjögren, Leif
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Municipal street maintenance challenges and management practices in Sweden2023Inngår i: Frontiers in Built Environment, E-ISSN 2297-3362, Vol. 9, artikkel-id 1205235Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The municipal street network acts as a multifunctional asset by providing people, vehicles and public services with a well-functioning infrastructure. To keep it in good condition, optimal maintenance measures are required which would result in an efficient use of taxpayers' money. This paper investigates the street network deterioration processes and the management practices that the municipal administrations have applied in Sweden. The study is based on a survey with Swedish municipalities using questionnaires and complementary interviews. The answers provide insight into a wide range of common pavement distresses and deterioration factors, along with pavement management practices. The study identifies that potholes, surface unevenness and alligator cracking are the most cited challenges, while pavement ageing, heavy traffic and patches are the most noted causes. Similarly, the cold climate and population density are influential factors in pavement deterioration. Allocation of the maintenance and rehabilitation and reconstruction budget is higher in the northern part of the country as well as in densely populated municipalities. Condition data collection and use of commercial Pavement Management Systems (PMS) are limited. Addressing the challenges effectively may be possible through the enhancement of the budget, feasible/clear guidelines from municipal councils/politicians, and reducing the gap between street network administrations and utility service providers.

    Fulltekst (pdf)
    fulltext
  • 3. Agustsson, Larus
    Danish experiences with speed zones/variable speed limits2001Inngår i: Proceedings of the conference Traffic Safety on Three Continents: International conference in Moscow, Russia, 19-21 September, 2001 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, s. 793-804Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The first Danish Road Safety Action plan in 1989 reduced the number of fatalities and casualties by 30% by the year 2000. The goal of the new Danish Road Safety Action Plan is to reduce the number of fatalities and serious casualties by 40% from 1998 to the year 2012. One of the actions that will be used to actuate this plan is the implementation of speed management and speed zones. This paper discusses the Danish experience with speed zones and variable speed limits.

  • 4.
    Ahmad, Numan
    et al.
    National University of Sciences and Technology, Pakistan.
    Ahmed, Anwaar
    National University of Sciences and Technology, Pakistan.
    Shah, Akhtar Ali
    University of Peshawar.
    Effectiveness of enforcement of seatbelt law: an exploratory empirical analysis using aggregate data2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Increasing motorization has enhanced the risk of road traffic crashes worldwide. Enforcing legislation on key risk factors such as seatbelt use by vehicle occupants is critical in reduction of road crash fatalities and injuries. This study estimated an ordered probit model to explore the relationship between effectiveness of enforcement of seatbelt law and different exploratory variables using data from World Health Organization. This study categorizes the enforcement of seatbelt law into four different levels including very low, low, medium and high. Through this study an attempt has been made to establish the relationship between effectiveness of enforcement of seat belt laws and socio-economic conditions, road crash fatalities, road safety legislation and public policies. Model results revealed that effectiveness of enforcement of seat belt law is significantly associated with road crash fatalities per thousand registered vehicles, legislation on cell phone use while driving, availability of training in emergency medicine for doctors, existence of national or sub-national policy for promoting walking and cycling, the existence of funded lead agency and maximum speed limit on rural road of a country. This research aims to provide a preliminary insight to planners and enforcement agencies to identify significance of seatbelt enforcement and suggest measures compatible to the typical socio-cultural and institutional set up for making the roads safer.

    Fulltekst (pdf)
    fulltext
  • 5.
    Ahmed, Abubeker
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Carlsson, Håkan
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Mätteknik och verkstad, MÄT.
    Lundberg, Thomas
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Utvärdering av gummiasfalt: provväg E22 Mönsterås : etapp 12019Rapport (Annet vitenskapelig)
    Abstract [sv]

    Laboratorieundersökningar och vägytemätningar utfördes på referens- och gummimodifierade asfaltbeläggningar på E22 Mönsterås.

    Laboratorieundersökningarna visar inte några tydliga skillnader i styvhet och skjuvmodul mellan massorna. Gummiasfalt har dock lägre fasvinkel jämfört med referens vilket betyder att gummiasfalten är mer elastisk. Gummiasfalten visar också lite lägre modul i låga temperaturer och lite högre modul i höga temperaturer vilket är bra för sprickbildning vid låga temperaturer respektive deformationsstabilitet. Utmattningsprovningen visar att gummiasfalt har något bättre utmattningsegenskaper men skillnaderna är inte signifikanta.

    De initiala fältmätningarna visar inte på några framträdande skillnader mellan sträckorna utan mätresultaten är väldigt likvärdiga. Det är dock för tidigt att dra slutsatser efter mindre än ett års trafik och fortsatta tillståndutvecklingen bör följas ytterligare innan slutsatser kan dras. Någon skillnad i spårbildning mellan sträckorna kan inte fastställas p.g.a. systematiska variationer inom provsträckan.

    Fulltekst (pdf)
    fulltext
  • 6.
    Ahmed, Abubeker
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Hellman, Fredrik
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Full scale accelerated pavement tests to evaluate the performance of permeable and skeletal soil block pavement systems2016Inngår i: The Roles of Accelerated Pavement Testing in Pavement Sustainability: Engineering, Environment, and Economics, Springer International Publishing , 2016, s. 131-144Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    The increasing proportion of paved surface due to urbanization means that the conditions for urban trees and vegetation to survive have deteriorated. Factors such as air pollution, poor drainage, and the lack of usable soil for root growth contribute to the short life expectancy of urban trees. To meet this challenge, several permeable and "structural" or "skeletal soils" have been developed as alternatives to the typical compacted soil required to bear the weight of vehicular traffic in urban areas. The main objective of this study is to evaluate the resistance to permanent deformation of permeable and skeletal soil pavement structures based on full scale accelerated pavement tests (APT) using a heavy vehicle simulator (HVS). Interlocking paving stones of various types were used as permeable surface layer for the test structures. The results demonstrated that the permeable test structures exhibited higher permanent deformation than the corresponding impervious structures. The skeletal soil with bituminous base layer, however, produced performance comparable to the impervious reference test structures.

  • 7.
    Ahmed, Abubeker
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Rahman, Shafiqur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Iron sand as a frost protection layer: thickness design charts2022Rapport (Annet vitenskapelig)
    Abstract [en]

    Frost depths and frost heaving calculations were performed to prepare design charts and tables for the iron sand (järnsand) layer thickness design for roads typically used for residential area, parking lots and other low to medium traffic roads, and for ground insulation. 

    A segregation potential based frost design method was employed to generate the design charts and tables. The segregation potential method allows the prediction of both frost heaving and frost penetration depth of a pavement structure for a prescribed winter temperature profile or freezing index. Thus, the iron sand layer thickness design tables/charts for roads were prepared for different levels of maximum permitted heaving criteria of 50, 80, 100, and 120 mm. Whereas for ground insulation, a design chart/table was prepared to eliminate any frost action in the ground. In addition to the frost design calculations, two triaxial tests were conducted to evaluate the bearing capacity of the iron sand material. The limited test results indicated that, the bearing capacity of iron sand is similar to conventional sand both in terms of stiffness as well as permanent deformation behavior.

    Fulltekst (pdf)
    fulltext
  • 8.
    Ahmed, Abubeker W.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA. KTH.
    Mechanistic-Empirical Modelling of Flexible Pavement Performance: Verifications Using APT Measurements2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Mechanistic-Empirical  (M-E)  pavement  design  procedures  are  composed  of  a  reliable  response model to estimate the state of stress in the pavement and distress models in order to predict the different types of pavement distresses due to the prevailing traffic and environmental conditions. One of the main objectives of this study was to develop a response model based on multilayer elastic  theory   (MLET)  with  improved  computational  performance  by   optimizing  the   time consuming parts of the MLET processes. A comprehensive comparison of the developed program with  two  widely  used  programs  demonstrated  excellent  agreement  and  improved  computational performance.  Moreover,  the  program  was  extended  to  incorporate  the  viscoelastic  behaviour  of bituminous materials through elastic-viscoelastic correspondence principle. A procedure based on collocation of linear viscoelastic (LVE) solutions at selected key time durations was also proposed that improved the computational performance for LVE analysis of stationary and moving loads. A comparison  of  the  LVE  responses  with  measurements  from  accelerated  pavement  testing  (APT) revealed a good agreement. Furthermore the developed response model was employed to evaluate permanent deformation models  for  bound  and  unbound  granular  materials  (UGMs)  using  full  scale  APTs.  The  M-E Pavement  Design  Guide  (MEPDG)  model  for  UGMs  and  two  relatively  new  models  were evaluated  to  model  the  permanent  deformation  in  UGMs.  Moreover,  for  bound  materials,  the simplified  form  of  the  MEPDG  model  for  bituminous  bound  layers  was  also  evaluated.  The measured  and  predicted  permanent  deformations  were  in  general  in  good  agreement,  with  only small discrepancies between the models. Finally, as heavy traffic loading is one of the main factors affecting the performance of flexible pavement, three types of characterizations for heavy traffic axle load spectrum for M-E analysis and design of pavement structures were evaluated. The study recommended an improved approach that enhanced the accuracy and computational performance.

    Delarbeid
    1. Evaluation of permanent deformation models for unbound granular materials using accelerated pavement tests
    Åpne denne publikasjonen i ny fane eller vindu >>Evaluation of permanent deformation models for unbound granular materials using accelerated pavement tests
    2013 (engelsk)Inngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 14, nr 1, s. 178-195Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Mechanistic-empirical (M-E) pavement design methods have become the focus of modern pavement design procedure. One of the main distresses that M-E design methods attempt to control is permanent deformation (rutting). The objective of this paper is to evaluate three M-E permanent deformation models for unbound granular materials, one from the US M-E pavement design guide and two other relatively new models. Two series of heavy vehicle simulator (HVS) tests with three different types of base material were used for this purpose. The permanent deformation, wheel loading, pavement temperature, and other material properties were continuously controlled during the HVS tests. Asphalt concrete layers were considered as linear elastic where stress-dependent behaviour of unbound materials was considered when computing responses for the M-E permanent deformation models with a nonlinear elastic response model. Traffic wandering was also accounted for in modelling the traffic by assuming it was normally distributed and a time-hardening approach was applied to add together the permanent deformation contributions from different stress levels. The measured and predicted permanent deformations are in general in good agreement with only small discrepancies between the models. Model parameters were also estimated for three different types of material.

    sted, utgiver, år, opplag, sider
    Taylor & Francis Group, 2013
    Emneord
    Rutting (wheel), Unbound base, Granular, Stress (in material)
    HSV kategori
    Forskningsprogram
    Road: Highway design, Road: Pavement design; Road: Materials, Road: Aggregate and stone materials
    Identifikatorer
    urn:nbn:se:vti:diva-6941 (URN)10.1080/14680629.2012.755936 (DOI)
    Tilgjengelig fra: 2014-07-17 Laget: 2014-07-17 Sist oppdatert: 2022-10-21bibliografisk kontrollert
    2. Modeling of flexible pavement structure behavior: Comparisons with Heavy Vehicle Simulator measurements
    Åpne denne publikasjonen i ny fane eller vindu >>Modeling of flexible pavement structure behavior: Comparisons with Heavy Vehicle Simulator measurements
    2012 (engelsk)Inngår i: Advances in Pavement Design Through Full-Scale Accelerated Pavement Testing / [ed] Jones, Harvey, Mateos & Al-Qadi, London: Taylor & Francis Group, 2012, s. 493-503Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

     A response model to be employed in a mechanistic-empirical pavement performance predictionmodel based on multilayer elastic theory has been developed. An iterative approach using a method of successiveover-relaxation of a stress dependency model is used to account for the nonlinear behavior of unbound materials. Asphalt and subgrade materials are assumed to be linear elastic. The response model was verified against two series of Heavy Vehicle Simulator (HVS) response measurements made under a variety of wheel loadconfigurations and at different pavement temperatures. A comparison with Falling Weight Deflectometer (FWD)data was also carried out. The model was subsequently used to predict permanent deformation from the HVS testing using simple work hardening models. A time hardening approach has been adopted to combine permanentdeformation contributions from stress levels of different magnitude.The response model outputs and the predictedpermanent deformations were generally in good agreement with the measurements.

    sted, utgiver, år, opplag, sider
    London: Taylor & Francis Group, 2012
    Emneord
    Pavement, Simulation, Deflectograph, Model
    HSV kategori
    Forskningsprogram
    Road: Highway design, Road: Pavement design
    Identifikatorer
    urn:nbn:se:vti:diva-6942 (URN)10.1201/b13000-61 (DOI)ISBN 978-0-415-62138-0 (ISBN)
    Konferanse
    The 4th International Conference on Accelerated Pavement Testing
    Tilgjengelig fra: 2014-07-17 Laget: 2014-07-17 Sist oppdatert: 2022-10-21bibliografisk kontrollert
    3. Fast layered elastic response program for the analysis of flexible pavement structures
    Åpne denne publikasjonen i ny fane eller vindu >>Fast layered elastic response program for the analysis of flexible pavement structures
    2013 (engelsk)Inngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 14, nr 1, s. 196-210Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    One of the key components in analysing pavement structural behaviour is the response model which is used to estimate the stresses, strains and displacements of the pavement structure subjected to the existing traffic, taking into account the material properties and prevailing environmental conditions. Multilayer elastic theory (MLET) is often preferred over other methods such as the finite element method, due to its computational performance for repeated applications. A new elastic response analysis program has been developed based on the Burmister MLET theory to calculate the response of flexible pavement structures. In the development of the program, the time-consuming part of MLET processes was optimised. To improve the convergence and accuracy of responses in the vicinity of the surface of the top layer, an approach based on Richardson's extrapolation was employed. Moreover, an iterative approach to model stress dependency of unbound granular materials was incorporated. A comprehensive comparison of the program with two frequently used programs demonstrated an excellent agreement and improved performance.

    sted, utgiver, år, opplag, sider
    Taylor & Francis Group, 2013
    Emneord
    Elasticity, Flexible pavement, Model (not math)
    HSV kategori
    Forskningsprogram
    Road: Highway design, Road: Surfacing
    Identifikatorer
    urn:nbn:se:vti:diva-6944 (URN)10.1080/14680629.2012.757558 (DOI)
    Tilgjengelig fra: 2014-07-17 Laget: 2014-07-17 Sist oppdatert: 2022-10-21bibliografisk kontrollert
    4. Characterization of heavy traffic axle load spectra for mechanistic-empirical pavement design applications
    Åpne denne publikasjonen i ny fane eller vindu >>Characterization of heavy traffic axle load spectra for mechanistic-empirical pavement design applications
    2015 (engelsk)Inngår i: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 16, nr 6, s. 488-501Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

     Heavy traffic axle load spectrum (ALS) is  one of the key inputs for mechanistic-empirical analysis and design of pavement structures. Frequently, the entire ALS is aggregated into Equivalent Number of Single Axle Loads (ESAL) or assumed to have Constant Contact  Area  (CCA)  or  Constant  Contact  Pressure  (CCP).  These characterizations affect the accuracy and computational performance of the pavement analysis. The objective of this study was to evaluate these  characterizations  based  on  predicted  performances  to  rutting and fatigue cracking of several pavement structures subjected to ALS data collected from 12 Bridge-Weigh-In-Motion stations. The results indicated  that  for  layers  below  the  top  25  cm,  all  characterizations produced similar values of predicted rutting. However, for the top 25 cm, the methods differed in the predicted performances to rutting and fatigue cracking. Furthermore an improvement to the CCA approach was proposed that enhanced the accuracy while maintaining the same level of computational performance.

    sted, utgiver, år, opplag, sider
    Taylor & Francis Group, 2015
    Emneord
    Axle load, Heavy vehicle, Pavement design, Rutting, Cracking, Prediction, Accuracy
    HSV kategori
    Forskningsprogram
    30 Road: Highway design, 32 Road: Pavement design
    Identifikatorer
    urn:nbn:se:vti:diva-6945 (URN)10.1080/10298436.2014.943131 (DOI)000354458200003 ()2-s2.0-84929283717 (Scopus ID)
    Tilgjengelig fra: 2014-07-17 Laget: 2014-07-17 Sist oppdatert: 2022-10-21bibliografisk kontrollert
    5. Evaluation of a permanent deformation model for asphalt concrete mixtures using extra-large wheel-tracking and heavy vehicle simulator tests
    Åpne denne publikasjonen i ny fane eller vindu >>Evaluation of a permanent deformation model for asphalt concrete mixtures using extra-large wheel-tracking and heavy vehicle simulator tests
    2015 (engelsk)Inngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 16, nr 1, s. 154-171Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    This paper evaluates a mechanistic–empirical permanent strain model for asphalt concrete mixtures. The evaluation was carried out based on two different types of tests: an extra-large wheel-tracking (ELWT) test and a full-scale accelerated pavement test using a heavy vehicle simulator (HVS). Asphalt slabs from three different types of asphalt mixtures were prepared for the ELWT test and tested at several pavement temperatures and tyre inflation pressures. Lateral wandering was also incorporated.

    The measured permanent deformations in the asphalt slabs were thereafter modelled using the permanent strain model from the US Mechanistic-Empirical Pavement Design Guide and model parameters were estimated for the three types of mixes. For validation, data from an HVS tested pavement structure consisting of the same asphalt mixtures as those tested using the ELWT were used. A set of calibration factors for the three mixtures were therefore obtained between the two tests. In all cases, the calibration factors were within ±20% from unity. Differences in geometry, scale, wheel loading configuration as well as the speed of loading between the two test devices could be the possible reasons for the differences in observed calibration factors.

    Emneord
    Flexible pavement, Bituminous mixture, Mathematical model, Strain, Simulation, Loading
    HSV kategori
    Forskningsprogram
    30 Road: Highway design, 32 Road: Pavement design
    Identifikatorer
    urn:nbn:se:vti:diva-9307 (URN)10.1080/14680629.2014.987311 (DOI)000349451300010 ()2-s2.0-84922800575 (Scopus ID)
    Tilgjengelig fra: 2016-03-03 Laget: 2016-03-02 Sist oppdatert: 2022-12-09bibliografisk kontrollert
    6. Numerical validation of viscoelastic responses of a pavement structure in a full-scale accelerated pavement test
    Åpne denne publikasjonen i ny fane eller vindu >>Numerical validation of viscoelastic responses of a pavement structure in a full-scale accelerated pavement test
    2015 (engelsk)Inngår i: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268XArtikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    This paper demonstrates the application of a generalised layered linear viscoelastic (LVE) analysis for estimating the structural response of flexible pavements. A comparison of the direct layered viscoelastic responses with approximate solutions based on the linear elastic (LE) and LVE collocation methods was also carried out. The different approaches were implemented by extending a layered elastic program with an improved computational performance. The LE and LVE collocation methods were further extended for analysis of pavements under moving loads.

    The methods were illustrated by analysing a pavement structure subjected to moving wheel loads of 30, 50, 60 and 80 kN using a Heavy Vehicle Simulator (HVS). The various responses (stresses and strains) in the pavement, at pavement temperatures of 0, 10 and 20°C, were measured using various types of sensors installed in the structure. It was shown that the approximated LVE solution based on the LE collocation method agreed very well with the measurements and is computationally the least expensive.

    Emneord
    Flexible pavement, Viscoelasticity, Unbound base, Loading, Mathematical model, Calculation
    HSV kategori
    Forskningsprogram
    30 Road: Highway design, 32 Road: Pavement design
    Identifikatorer
    urn:nbn:se:vti:diva-9278 (URN)10.1080/10298436.2015.1039003 (DOI)2-s2.0-84929238620 (Scopus ID)
    Tilgjengelig fra: 2016-03-07 Laget: 2016-03-02 Sist oppdatert: 2022-12-09bibliografisk kontrollert
  • 9.
    Ahmed, Abubeker W.
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Biligiri, Krishna Prapoorna
    Department of Civil Engineering Indian Institute of Technology Kharagpur .
    Hakim, Hassan
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    An Algorithm to Estimate Rational Values of Phase Angles and Moduli of Asphalt Mixtures2013Inngår i: International Journal of Pavement Research and Technology (IJPRT), ISSN 1997-1400, Vol. 6, nr 6, s. 745-754Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The objective of this study was to develop and evaluate an algorithm based on Fast Fourier Transform (FFT) that can calculate rational values of phase angle (f) and moduli of the variants of asphalt mixtures for the data obtained from the different frequency sweep tests. f and moduli for ten different asphalt mixtures resulting in over 690 data points collected from both USA and Sweden were computed using FFT. Theoretical observations revealed that there were significant differences for f between FFT and other methods to the order of 10-50%; however, there was no difference in moduli estimates for any mix and was independent of the test. Precisely, the FFT method produced rational f for mixtures that deviate from conventional mixture properties. Furthermore, statistical comparisons corroborated the predicted f estimates indicative of significant differences between the analysis techniques; but, the moduli were unaffected by the analysis methods. The study successfully illustrated the FFT technique, a user-friendly analytical procedure that can obviate the errors in the rational estimation of the acutely sensitive viscoelastic parameters.

    Fulltekst (pdf)
    fulltext
  • 10.
    Ahmed, Abubeker W.
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Characterization of heavy traffic axle load spectra for mechanistic-empirical pavement design applications2015Inngår i: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 16, nr 6, s. 488-501Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

     Heavy traffic axle load spectrum (ALS) is  one of the key inputs for mechanistic-empirical analysis and design of pavement structures. Frequently, the entire ALS is aggregated into Equivalent Number of Single Axle Loads (ESAL) or assumed to have Constant Contact  Area  (CCA)  or  Constant  Contact  Pressure  (CCP).  These characterizations affect the accuracy and computational performance of the pavement analysis. The objective of this study was to evaluate these  characterizations  based  on  predicted  performances  to  rutting and fatigue cracking of several pavement structures subjected to ALS data collected from 12 Bridge-Weigh-In-Motion stations. The results indicated  that  for  layers  below  the  top  25  cm,  all  characterizations produced similar values of predicted rutting. However, for the top 25 cm, the methods differed in the predicted performances to rutting and fatigue cracking. Furthermore an improvement to the CCA approach was proposed that enhanced the accuracy while maintaining the same level of computational performance.

  • 11.
    Ahmed, Abubeker W.
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Evaluation of a permanent deformation model for asphalt concrete mixtures using extra-large wheel-tracking and heavy vehicle simulator tests2015Inngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 16, nr 1, s. 154-171Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper evaluates a mechanistic–empirical permanent strain model for asphalt concrete mixtures. The evaluation was carried out based on two different types of tests: an extra-large wheel-tracking (ELWT) test and a full-scale accelerated pavement test using a heavy vehicle simulator (HVS). Asphalt slabs from three different types of asphalt mixtures were prepared for the ELWT test and tested at several pavement temperatures and tyre inflation pressures. Lateral wandering was also incorporated.

    The measured permanent deformations in the asphalt slabs were thereafter modelled using the permanent strain model from the US Mechanistic-Empirical Pavement Design Guide and model parameters were estimated for the three types of mixes. For validation, data from an HVS tested pavement structure consisting of the same asphalt mixtures as those tested using the ELWT were used. A set of calibration factors for the three mixtures were therefore obtained between the two tests. In all cases, the calibration factors were within ±20% from unity. Differences in geometry, scale, wheel loading configuration as well as the speed of loading between the two test devices could be the possible reasons for the differences in observed calibration factors.

  • 12.
    Ahmed, Abubeker W.
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Evaluation of permanent deformation models for unbound granular materials using accelerated pavement tests2013Inngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402, Vol. 14, nr 1, s. 178-195Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mechanistic-empirical (M-E) pavement design methods have become the focus of modern pavement design procedure. One of the main distresses that M-E design methods attempt to control is permanent deformation (rutting). The objective of this paper is to evaluate three M-E permanent deformation models for unbound granular materials, one from the US M-E pavement design guide and two other relatively new models. Two series of heavy vehicle simulator (HVS) tests with three different types of base material were used for this purpose. The permanent deformation, wheel loading, pavement temperature, and other material properties were continuously controlled during the HVS tests. Asphalt concrete layers were considered as linear elastic where stress-dependent behaviour of unbound materials was considered when computing responses for the M-E permanent deformation models with a nonlinear elastic response model. Traffic wandering was also accounted for in modelling the traffic by assuming it was normally distributed and a time-hardening approach was applied to add together the permanent deformation contributions from different stress levels. The measured and predicted permanent deformations are in general in good agreement with only small discrepancies between the models. Model parameters were also estimated for three different types of material.

  • 13.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Mechanistic modelling of HVS flexible pavement structure2012Inngår i: EPAM 2012: Malmö, Sweden, 5–7 September: 4th European pavement and asset management conference, Linköping: Statens väg- och transportforskningsinstitut, 2012, , s. 13Konferansepaper (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    A response model to be employed in a mechanistic-empirical pavement performance prediction model based on multilayer elastic theory has been developed. An iterative approach using a method of successive over-relaxation of stress dependency model is used to account for the nonlinear behaviour of unbound materials. Asphalt and subgrade materials are assumed as linear elastic. The response model is verified using heavy vehicle simulator (HVS) response measurements made under variety of wheel load configurations and at different pavement temperatures. The permanent deformation behaviours of the HVS structure is also modelled using mechanistic empirical approach and by employing permanent deformation prediction models. A time hardening approach has been applied to combine permanent deformation contributions from stress levels of different magnitude. The response model outputs and the predicted permanent deformations are in general in good agreement with the measurements.

  • 14.
    Ahmed, Abubeker W.
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Numerical validation of viscoelastic responses of a pavement structure in a full-scale accelerated pavement test2015Inngår i: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268XArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper demonstrates the application of a generalised layered linear viscoelastic (LVE) analysis for estimating the structural response of flexible pavements. A comparison of the direct layered viscoelastic responses with approximate solutions based on the linear elastic (LE) and LVE collocation methods was also carried out. The different approaches were implemented by extending a layered elastic program with an improved computational performance. The LE and LVE collocation methods were further extended for analysis of pavements under moving loads.

    The methods were illustrated by analysing a pavement structure subjected to moving wheel loads of 30, 50, 60 and 80 kN using a Heavy Vehicle Simulator (HVS). The various responses (stresses and strains) in the pavement, at pavement temperatures of 0, 10 and 20°C, were measured using various types of sensors installed in the structure. It was shown that the approximated LVE solution based on the LE collocation method agreed very well with the measurements and is computationally the least expensive.

  • 15.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA. University of Iceland.
    Viscoelastic Response Modelling of a Pavement under Moving Load2016Inngår i: Transportation Research Procedia, 2016, Vol. 14, s. 748-757Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper demonstrates the application of a generalized layered linear viscoelastic (LVE) analysis for estimating flexible pavements' structural response. The procedure is based on the Multi-Layered Elastic Theory (MLET) and the elastic-viscoelastic correspondence principle using a numerical inverse Laplace transform. A comparison of the direct layered viscoelastic responses with approximate solutions based on the elastic collocation method was also carried out. Furthermore, it is proposed to use the collocation method using LVE solutions at selected time durations in order to improve the accuracy of the elastic collocation method. The LVE collocation method was further extended for analysis of moving loads. The method was illustrated by analysing a pavement structure subjected to moving wheel loads of 30, 50, 60 and 80 kN using a Heavy Vehicle Simulator (HVS). The various responses (stresses and strains) in the pavement, at different pavement temperatures, were measured using various types of sensors installed in the structure. The LVE calculations agreed very well with the measurements.

  • 16.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Gudmarsson, Anders
    PEAB.
    Waldemarson, Andreas
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Utvärdering av styvhetsförändring i asfaltmassor med returasfalt, rejuvenatorer och polymerer2020Rapport (Annet vitenskapelig)
    Abstract [sv]

    Returasfalt (RA) som återanvänds i nya beläggningar bidrar till att reducera miljöpåverkan från beläggningsarbeten. Att använda rejuvenatorer eller att använda ett mjukare bitumen är två metoder för att kompensera mot det hårdare åldrade bindemedlet i RA massorna. Rejuvenatorer reducerar styvheten och sprödheten i bitumen vilket förbättrar motståndet mot sprickbildning. Det saknas dock kunskap om beläggningar med rejuvenatorer ökar risken för initiala deformationer orsakade av tung trafik. Liksom för massor med rejuvenatorer är det inte undersökt hur massor med inblandat mjukare bitumen i RA påverkar den nytillverkade massans styvhet och deformationsstabilitet.

    Syftet med projektet är att utvärdera styvhetsförändring med tiden i labboratorietillverkade asfalt-beläggningar när rejuvenatorer eller mjukare bitumen används för att möjliggöra en ökad halt återvunnen asfalt. I detta projekt utfördes laboratorieundersökningar genom pressdragprovning, modalanalys och skjuvtest på fem olika asfaltmassor med RA, rejuvenatorer och polymerer.

    Laboratorieundersökningarna visar att det inte finns några tydliga skillnader i styvhetsförändring med tiden mellan de olika massorna under de första 3 veckorna (7 till 21 dagar). Men det finns skillnader i styvhetsutveckling med tiden på längre tidsperiod. Skjuvprovning utfördes ett år efter tillverkning av massorna och visar att kompensationsmetoderna såsom bitumenblandning eller rejuvenatorer ger liknande stabilitet för slutprodukten. Dessutom har polymermodifierade massor visat lägre modul vid låga temperaturer och högre modul vid höga temperaturer jämfört med massor utan polymermodifierat bindemedel, vilket är bra för motståndet mot sprickbildning vid låga temperaturer respektive för deformationsstabilitet vid höga temperaturer. Lagring och konditionering av provkropparna och samtliga mätningar utfördes i laboratoriemiljö vilket begränsar resultaten till att endast representera styvhetsförändringen som sker utan påverkan från klimat och trafik.

    Fulltekst (pdf)
    fulltext
  • 17.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Rahman, Mohammad Shafiqur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Impact of longer and heavier vehicles on the performance of asphalt pavements: A laboratory study2018Inngår i: Bearing Capacity of Roads, Railways and Airfields - Proceedings of the 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields, BCRRA 2017, CRC Press/Balkema , 2018, s. 483-490Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Historically, Longer and Heavier Vehicles (LHVs) have been permitted to operate in Sweden. Since 1996 and as of the beginning of 2015, the maximum gross vehicle weight of 60 tons and a length of up to 25.25 m have been permitted. The Swedish Transport Administration has decided to further increase the maximum gross vehicle weight to 74 tons and studies are undergoing to evaluate the impact of the proposed LHVs on existing transport infrastructure. To this end, repeated load triaxial tests and indirect tensile fatigue tests were conducted on selected conventional asphalt mixtures to investigate and quantify the impact of single, tandem and tridem axle configurations on permanent deformation and fatigue performances of conventional asphalt pavements. In addition, fatigue tests for selected LHV scenarios were conducted. This paper presents the results of the laboratory tests and simulations conducted. The test results have clearly demonstrated the impact of the different axle configurations on the rutting and fatigue performances of the mixture. Furthermore, such results can explain the significance of axle configuration on modelling the rutting and fatigue performances of asphalt pavements.

  • 18.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Rahman, Mohammad Shafiqur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Impact of tire types and configurations on responses of a thin pavement structure2018Inngår i: Advances in Materials and Pavement Performance Prediction: Proceedings of the International AM3P Conference, 2018, London: CRC Press , 2018, s. 271-274Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The objective of this study was to assess the impact of tire and tire configurations on the responses of a thin asphalt pavement structure by means of full-scale tests using a Heavy Vehicle Simulator (HVS). A total of six different types of tires, four single and two dual tire configurations, were investigated. The structure was instrumented to measure tensile strains at the bottom of the asphalt layer and vertical stresses and strains in the unbound base, subbase and subgrade layers. The results indicated that, in general, single tire configurations produced higher tensile strain at the bottom of the asphalt layer and higher vertical stresses and strains in unbound base, subbase and subgrade layers.

  • 19.
    Ahmed, Abubeker W
    et al.
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Said, Safwat
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Lu, Xiaohu
    Nynäs AB.
    Carlsson, Håkan
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Mätteknik och verkstad, MÄT.
    Pavement performance follow-up and evaluation of polymer-modified test sections2019Inngår i: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 20, nr 12, s. 1474-1487Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Between 2003 and 2006, a test road consisting of several conventional and polymer-modified structures was built on a motorway. Different combinations of styrene–butadiene–styrene (SBS) and ethyl vinyl acetate (EVA) polymer-modified binders were used. The test structures have been in service since then and have been monitored for over 9 years. The resistance of the different types of asphalt concrete mixes to rutting and cracking was measured and predicted. The impact of ageing on the mixes was also evaluated. Although all the sections are in good condition after 9 years of traffic, the predicted differences between the test sections based on the PEDRO (Permanent Deformation of asphalt concrete layers for Roads) approach and laboratory evaluations are noticeable. Lateral wander and transverse profile measurements indicated that studded winter tyre wear contributed to most of the rutting compared to permanent deformation due to heavy traffic. The unmodified mixes exhibited considerable ageing and the SBS-modified mixes were least affected by ageing. Furthermore, the SBS-modified base mix produced significantly better fatigue resistance than the conventional base mix. However, further investigations of the relationships between bitumen and mix properties and further follow-ups of the test sections are recommended to validate the findings.

    Fulltekst (pdf)
    fulltext
  • 20.
    Ainge, Mike
    et al.
    TRL, UK.
    Altekoester, Carsten
    BASt, Germany.
    Nelson, Paul
    TRL, UK.
    Phillips, Steve
    FEHRL.
    Sandberg, Ulf
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ. Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö och trafikanalys, MTA.
    Steven, Heinz
    TÜV Nord, Germany.
    Treleven, Colin
    TRL, UK.
    Watts, Greg
    TRL, UK.
    Final report si2.408210: Tyre/road noise2007Rapport (Annet vitenskapelig)
    Fulltekst (pdf)
    Final report
    Fulltekst (pdf)
    Appendices
  • 21.
    Ait Ali, Abderrahman
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Odolinski, Kristofer
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Pålsson, Björn
    Mechanics and Maritime Sciences/CHARMEC, Chalmers.
    Torstensson, Peter
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Evaluating the mix of maintenance activities on railway crossings with respect to life-cycle costs2023Rapport (Annet vitenskapelig)
    Abstract [en]

    Switches & crossings (S&Cs) are vital assets as they allow for increased railway capacity by introducing flexibility and connectivity in railway networks. At the same time, this makes them critical since they can cause costly delays and disruptions if they are not well maintained. This motivates studies to improve maintenance strategies of S&Cs, considering both the life-cycle costs (LCC) of the assets and socio-economic transportation costs for passengers and freight customers. In this paper, the interdependence between deterioration mechanisms, maintenance activities, and expected LCC (including transportation costs) is investigated using a combination of mechanical and econometric modelling. The interrelation between the degradation of contact geometry and track settlement is analysed using simulations of dynamic vehicle–turnout interaction. Long-term mechanical degradation of the S&C is simulated for different maintenance strategies that correspond to different timing of the associated maintenance measures (crossing repair welding and tamping). This provides the basis for analysing the interdependence between preventive and corrective activities using econometric modelling. Based on a case study of a common type of S&Cs in the Swedish infrastructure, the impact of different maintenance strategies on LCC and transportation costs is analysed. Opportunities and challenges in the development of more socio-economically effective maintenance strategies of S&Cs are discussed.

    Fulltekst (pdf)
    fulltext
  • 22.
    Ait Ali, Abderrahman
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Pålsson, Björn
    Chalmers University of Technology, Department of Mechanics and Maritime Sciences/CHARMEC, Sweden.
    Odolinski, Kristofer
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Torstensson, Peter
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Evaluation of long-term maintenance of switches & crossings with respect to life-cycle costs and socio-economic impact2022Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Switches & crossings (S&Cs) are vital assets as they allow for increased railway capacity by introducing flexibility and connectivity in railway networks. At the same time this makes them critical, and they can cause major delays and disruptions if they are not well maintained. This motivates studies to improve maintenance strategies of S&Cs, considering both life-cycle costs (LCC) of the assets and other additional socio-economic costs (e.g., transportation costs for passengers and freight customers). In this paper, the interdependence between deterioration mechanisms, maintenance activities, and expected LCC (including transportation costs) is investigated using a combination of mechanical and econometric modelling.

    The interrelation between the degradation of contact geometry and track settlement is analysed using simulations of dynamic vehicle–turnout interaction. Changes in the timing of the associated maintenance measures (crossing repair welding and tamping) are performed to investigate the impact on damage modes. This is then linked to LCC and transportation costs, which requires a distribution between preventive and corrective activities with respect to the simulated maintenance strategy. This relationship is investigated by means of regression modelling: 𝑪𝒐𝒓𝒓𝒆𝒄𝒕𝒊𝒗𝒆=𝑓(𝑷𝒓𝒆𝒗𝒆𝒏𝒕𝒊𝒗𝒆,𝑿)

    where Corrective and Preventive represent the number of failures and the scheduled actions to prevent these failures, respectively. 𝑿 holds variables related to the traffic (volume, type of traffic, axle load, etc.) and the infrastructure (type of S&Cs, etc.).

    Fulltekst (pdf)
    PowerPoint
  • 23.
    Alfredsson, Magnus
    et al.
    NCC.
    Karlsson, Robert
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Sjögren, Leif
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Hintze, Staffan
    NCC.
    Johansson, Bo
    NCC.
    Lundström, Robert
    NCC.
    Winnerholt, Tomas
    Trafikverket.
    Funktionskriterier för vägkonstruktioner: Förstudie2010Rapport (Annet vitenskapelig)
    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

    Fulltekst (pdf)
    fulltext
  • 24.
    Allirani, Hemanthini
    et al.
    National Institute of Technology, Tiruchirappalli.
    Santhakumar, Moses
    National Institute of Technology, Tiruchirappalli.
    Kumar, Kavitha
    National Institute of Technology, Tiruchirappalli.
    Analysis of factors influencing traffic accidents: a case study of Tiruchirappalli city2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

     Road safety is a major concern in many developing countries including India. Road accidents are responsible for an increase in deaths and disability throughout the world. Road accidents lead to loss of life, property and affect the general welfare of the people and the economy. India accounts for 10% of global road accidents and has the highest death rate in the world. In India, traffic fatalities have increased by 4.6% from 2014 to 2015. The analysis of road accident data reveals that about 57 accidents and 17 deaths take place every hour on an average in Indian roads. Road accidents have been increasing alarmingly in Tamil Nadu, being a major state contributing to total no. of accidents in India. Tamil Nadu reported the highest number of road accidents in 2015 sharing about 13.8% of the total accidents in the country. Tamil Nadu accounts for about 10.7% and 15.9% of total road fatalities and injury accidents in the entire country. Tamil Nadu ranked second highest and first in the country for fatalities and minor injury accidents.

    A case study of Tiruchirappalli city is considered for the present study. Tiruchirappalli city is situated at the geographical center of Tamil Nadu. Every year, a number of people are killed or injured due to road accidents. In Tiruchirappalli between the year 2010 and 2015, about 924 fatal accidents were reported and 974 people were killed due to road accidents. Hence, it is essential to find solutions to mitigate the problem. Road accidents are influenced by many factors such as traffic flow, geometric design of road sections, horizontal curvature, vertical grade, lane width, and shoulder width etc. Predicting the exact cause for the road accident is complex. Studies were done relating the factors like traffic volume, speed, road characteristics, road geometrics etc., with the road accidents. This study focuses on analysing road accident data and the relationship between various factors influencing road accidents so that suitable accident remedial measures can be suggested to enhance road safety.

    Fulltekst (pdf)
    fulltext
  • 25.
    Almestrand Linné, Philip
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Sundström, Linnéa
    SIS.
    Hjalmarson, Mikael
    SIS.
    Standardisation for electric road systems: a review of ITS standards for the development of electric roads2020Rapport (Annet vitenskapelig)
    Abstract [en]

    As electric road system (ERS) technologies continue to reach higher levels of maturity, the need for standardisation of the field appears comparable to many other technically oriented areas.

    Standards can not only support industrial production and increase the opportunities for dissemination of innovations, they can also contribute to product safety, reliability, and a certain level of product quality. These are common arguments for standardisation of technologies, and they also apply readily to ERS. Standardisation is moreover essential for the interoperability, compatibility, and competitiveness of ERS, specifically from the perspective of facilitating a faster deployment of electric road systems as a promising future solution to replace the dominant position of fossil powered freight transport. Although currently under discussion, standardisation for ERS is however still only at the initial drafting phase.

    The purpose of this study was to increase knowledge of standardisation to promote the development of electric road systems. During the project a mapping was carried out to create an overview of standards that are directly or indirectly central for ERS in the area of intelligent transport systems (ITS). The study employed a combination of methods including an examination of ERS literature and ITS standards, a stakeholder workshop, and expert reviews of a tentative listing of ITS standards that are potentially applicable to ERS. The main result is a preliminary inventory of 111 ITS standards, including standards for electronic fee collection (EFC), where 99 standards have been deemed as potentially applicable to ERS.

    Fulltekst (pdf)
    fulltext
  • 26. Alten, Karoline
    et al.
    Deix, Stefan
    Peelen, Willy
    Wessels, Jos
    Courage, Wim
    Ravnikar Turk, Mojca
    Skaric Palic, Sandra
    Acalin, Nina
    Lundkvist, Sven-Olof
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Asset service condition assessment methodology (ASCAM Project)2012Inngår i: EPAM 2012, Malmö, Sweden, 5–7 September: 4th European pavement and asset management conference, Linköping: Statens väg- och transportforskningsinstitut, 2012, , s. 12Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Allocating financial resources among different sub-assets of a country’s road infrastructure is a challenge that is highly dependent on the strategic priorities and organisational structure of the infrastructure operator. While some agencies in Europe deal with pavements, bridges, tunnels or road furniture completely independently, others find that they have one mutual budget that needs to be shared out among the different assets in a way that represents their respective need for maintenance. The criteria upon which such allocations are based may be political, empirical, or based on stakeholder/user interests. The goal of the project ASCAM – Asset Service Condition Assessment Methodology – was to develop a framework for cross-asset management that can be used to objectively assign a budget to certain assets. While previous research projects have already compiled lists of various key performance indicators, ASCAM aimed to find mutual indices such as an “end user service level” that could be used to judge all sub-assets on equal terms and thus compare their condition on the same scale.

    By looking at asset management in the ASCAM partner countries and other European road agencies, the best-practice in individual asset management was extracted to develop the framework and perform a proof-of-concept for the project. While other projects such as PROCROSS within the same ERA-NET call also worked on cross-asset management – but from a top-down approach – ASCAM’s bottom-up approach looked at the more technical aspects of evaluating infrastructure condition and making a budgetary assignment based on the current and predicted state of the assets.

  • 27.
    Alzubaidi, Hossein
    Statens väg- och transportforskningsinstitut.
    Drift och underhåll av grusvägar: litteraturstudie1999Rapport (Annet vitenskapelig)
    Abstract [sv]

    Grusvägarna omfattar en väsentlig del av det svenska vägnätet. Det statliga vägnätet omfattar 98 015 km väg varav 22 136 km (22%) är grusvägar (1997). Förutom de statliga grusvägarna finns även ca 35000 km enskilda grusvägar med statsbidrag och ca 210 000 km skogsbilvägar.

    Föreliggande litteraturstudie ingår som en första del i doktorandprojektet "”Effektiva produktionsmetoder inom drift och underhåll av grusvägar”".

    Denna rapport behandlar drift och underhåll av grusvägar huvudsakligen med inriktning mot grusslitlagret under barmarksperioden. I Sverige och de nordiska länderna infaller denna period normalt mellan maj och oktober. Med begreppet ”Drift och underhåll av grusvägar” menas i denna rapport all verksamhet som berör skötsel av grusvägar så att vägen hålls i farbart skick. Litteraturstudien består av tio kapitel vars rubriker finns i följande avsnitt:

    Kapitel 1 "Inledning", kapitel 2 "Grundläggande begrepp", kapitel 3 "Allmänt om vägnätet", kapitel 4 "Nedbrytning av grusvägar", kapitel 5 "Tekniska krav på grusvägar i Sverige", kapitel 6 "Faktorer som påverkar underhållet av grusvägar", kapitel 7 "Metoder för drift och underhåll av grusvägar", kapitel 8 "Tillståndsbedömning av grusvägar", kapitel 9 "Planering och värdering av drift- och underhålls-åtgärder", kapitel 10 "Referenser", Kapitel 11 "Figur- och tabellförteckning".

    Fulltekst (pdf)
    FULLTEXT01
  • 28.
    Alzubaidi, Hossein
    Statens väg- och transportforskningsinstitut.
    Miljöeffekter av dammbindning av grusvägar1999Rapport (Annet vitenskapelig)
    Fulltekst (pdf)
    FULLTEXT01
  • 29.
    Alzubaidi, Hossein
    Statens väg- och transportforskningsinstitut.
    Operation and maintenance of gravel roads: a literature study1999Rapport (Annet vitenskapelig)
    Abstract [en]

    Gravel roads form a large percentage of the road network in Sweden. The public road network under the jurisdiction of the Swedish National Road Administration has a total length of some 98,000 kilometres. About 22,000 km of this network consists of gravel roads. In addition, there are about 74,000 kilometres of private road and 210,000 kilometres of forest roads. The report describes the present position in the operation and maintenance of gravel roads. It presents a comprehensive literature survey of current and recent national and international research. It deals only with summer maintenance and focuses primarily on roads surfaced with aggregate. The following areas are treated in the report: - Definitions and terms regarding the operation and maintenance of gravel roads.- General description of the Swedish road network. - Major factors causing deterioration of gravel roads. - Technical requirements for Swedish gravel roads. - Factors, which influence the operation and maintenance of gravel roads. - Operation and maintenance methods. - Condition assessment of gravel roads. - Planning and evaluation of operation and maintenance measures.

    Fulltekst (pdf)
    fulltext
  • 30.
    Alzubaidi, Hossein
    Statens väg- och transportforskningsinstitut.
    Tillståndsbedömning av grusvägar: en sammanfattning av: On rating of gravel roads. Doctoral thesis at the Division of Highway Engineering, Royal Institute of Technology, Stockholm2002Rapport (Annet vitenskapelig)
    Abstract [sv]

    Bakgrunden till avhandlingen är att en metod for tillståndsbedömning av grusvägar utgör en viktig del av ett styrsystem som skall leda till effektivitet i underhållsverksamheter. Vägverket tillämpar en metod för tillståndsbedömning av grusvägar, förkortad VVMB 106, vilken tar hänsyn till jämnhet, löst grus samt damm. Representativa 100 m långa slumpvalda grusvägsdelsträckor används för själva bedömningen. Delsträckans tillstånd indelas i klass 1 (god), klass 2 (godtagbar) eller klass 3 (dålig). Tillståndet bedöms tillfredsställande om delsträckan placeras i klass 1 eller klass 2 avseende jämnhet och bundenhet, annars bedöms det otillfredsställande. Syftet med avhandlingen är dels att analysera VVMB 106 för att finna dess svagheter, dels att utveckla en ny och förbättrad metod.

    Fulltekst (pdf)
    FULLTEXT01
  • 31.
    Andersson, Anders
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Fordonssystem och körsimulering, FSK.
    Blissing, Björn
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Fordonssystem och körsimulering, FSK.
    Carlsson, Håkan
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Mätteknik och verkstad, MÄT och VER.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Hellman, Fredrik
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Hjort, Mattias
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Fordonssystem och körsimulering, FSK.
    Ihs, Anita
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA.
    Kuttah, Dina K
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Nåbo, Arne
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Förare och fordon, FOF.
    Thorslund, Birgitta
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Förare och fordon, FOF.
    Designguide för Smarta gator2022Rapport (Annet vitenskapelig)
    Abstract [sv]

    Sammanfattningsvis definierar vi i denna guide ’smarta gator’ kort sagt som mångfunktionella, levande, långsamma, ekologiska och flexibla gator. Det övergripande målet med denna guide är följaktligen ”Smarta gator för en hållbar stadsutveckling”.

    Fulltekst (pdf)
    FULLTEXT01
  • 32.
    Andersson, Anna-Lena
    Swedish Transport Administration.
    Suicide And Accident Classification Method Used In Sweden2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Since 2010 Sweden has been presenting statistics on suicides in road traffic separately from that on fatalities caused by accidents. To undertake this, a method has been developed for classification of road traffic fatalities in order to determine if the fatality was caused by an accident or by a suicide. For more information, see abstract nr 180: “Suicide and accident classification methodology”.

    Fulltekst (pdf)
    fulltext
  • 33.
    Andersson, Anna-Lena
    et al.
    Trafikverket.
    Svensson, Kenneth
    Trafikverket.
    Suicide and accident classification methodology2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Fatalities in road traffic are not only due to accidents, some of them are suicides. Sweden has since 2010 described statistics on suicides in road traffic separately from fatalities caused by accidents. To implement this, a method has been developed for classification of road traffic fatalities in order to determine if the fatality was caused by an accident or by a suicide.The work has been carried out in cooperation between The Swedish Transport Administration, The Swedish Transport Agency, The National Board of Forensic Medicine and Suicide Prevention Western Sweden.

    Fulltekst (pdf)
    fulltext
  • 34.
    Andersson, Arne
    et al.
    AB Previa/ARA miljö.
    Jacobson, Torbjörn
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Persson, Bengt-Olle
    Peab Asfalt.
    Tillsatsmedel i asfalt: påverkan på arbetsmiljö och omgivning (2006-02-06). Slutrapport2006Rapport (Annet vitenskapelig)
    Abstract [sv]

    Vissa tillsatsmedel upplevs idag som besvärliga för arbetsmiljön vid tillverkning och utläggning av asfaltmassa. Vidstående projekt som finansierats av SBUF och Peab Asfalt AB syftar till att ta fram relevanta fakta om tillsatsmedel och dess hälso- och miljöproblem. Projektet har dels inriktats som en förstudie av vad som hitintills har gjorts inom asfaltmiljöområdet både i Sverige och i utlandet, dels kompletterande fältmätningar vid asfaltläggning av polymermodifierad asfalt. Studien har utförts i samarbete mellan Peab Asfalt AB, VTI och Previa/ARA-miljö.

    Fulltekst (pdf)
    fulltext
  • 35.
    Andersson, G
    et al.
    Svenska Väginstitutet.
    Lundeberg, Erik
    Svenska Väginstitutet.
    Undersökningar rörande bromslängden för bilar vid olika väglag1931Rapport (Annet vitenskapelig)
    Fulltekst (pdf)
    fulltext
  • 36.
    Andersson, Henrik
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Jonsson, Lina
    Statens väg- och transportforskningsinstitut.
    Ögren, Mikael
    Statens väg- och transportforskningsinstitut.
    Bullervärden för samhällsekonomisk analys: beräkningar för väg- och järnvägsbuller2009Rapport (Annet vitenskapelig)
    Abstract [sv]

    Noise is a significant social problem. For example, more than 20 per cent of the European Union's population is exposed to higher noise than what is considered acceptable. The transport sector is a major contributor to society's increasing noise problem, due to increased traffic volumes and urbanization exposing more people to noise. Road traffic is admittedly the largest individual noise source in the transport sector, but other transport modes such as aircraft and railways are also responsible for considerable noise emissions. Noise entails costs for the society. This fact, and that society has different needs, means that policies and projects to reduce noise levels need to be evaluated to secure an efficient resource allocation. Benefit cost analysis is a powerful tool to evaluate noise abatement, but it requires both benefits and costs to be measured in a common metric, i.e. in monetary values. Today's official monetary values for all modes are based on the impact of road-traffic noise on property prices. It is a well established fact that the disturbance which individuals experience differs between modes, and therefore there is a need to estimate monetary values based on the respective modes. This report focuses on road and rail noise, two noise sources with different characteristics. This study describes the need to revise the current official Swedish policy values for noise abatement. Current values for road-traffic noise show a progressive relationship between the social cost and the noise level that is too strong, and values for railway noise has been missing and instead based on results for road noise. Valuation of health effects should also be based on EKM since it is sanctioned within the EU, instead of the approach now proposed by ASEK based on estimated total social costs from noise exposure in relation to estimates from willingness to pay studies.

    Fulltekst (pdf)
    FULLTEXT01
  • 37.
    Andersson, Kjell
    et al.
    Statens väg- och transportforskningsinstitut.
    Nilsson, Göran
    Statens väg- och transportforskningsinstitut.
    The effects on accidents of compulsory use of running lights during daylight in Sweden1981Rapport (Annet vitenskapelig)
    Abstract [en]

    The report is an attempt to describe the effects on accidents of compulsory use of running lights - low beam or special lamps - during daylight in Sweden.

    The study is carried out on police reported traffic accidents with personal injury in Sweden. The before and after periods are two years before and two years after the operative day of the law, October 1st 1977.

    The use of running lights in the before-period was roughly speaking 50 % and in the after-period over 95 %.

    The basic assumption is that the use of running lights in daylight influences multiple accidents in daylight and only those. The method used is to study the relation of daylight to darkness numbers of multiple accidents. The corresponding relation for single vehicle accidents is taken as control.

    The estimated total effect depends both on the subdivision of accident data and the method used for accidents with unprotected road users. The estimates vary from 6 to 13 % reduction - from the before-period to the after period - of multiple accidents during daylight or 450 to 1100 less police reported accidents with personal injury per year. The estimated effects are not significant on a 5 % level.

    Fulltekst (pdf)
    fulltext
  • 38.
    Andersson, Mats
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Marginal railway renewal costs: a survival data approach2007Rapport (Annet vitenskapelig)
    Abstract [en]

    In this paper, renewal costs for railway tracks are investigated using survival analysis. The purpose is to derive the effect from increased traffic volumes on rail renewal cycle lengths and to calculate associated marginal costs. A flow sample of censored data containing almost 1 500 observations on the Swedish main railway network is used. We specify Weibull accelerated failure time regression models, and estimate deterioration elasticities for total tonnage as well as for passenger and freight tonnages separately. Marginal costs are calculated as a change in present values of renewal costs from premature renewal following increased traffic volumes.

    Fulltekst (pdf)
    fulltext
  • 39.
    Andersson, Mats
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Borlänge, TEK-B.
    Smith, Andrew
    Institute for Transport Studies, University of L eeds.
    Wikberg, Åsa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Borlänge, TEK-B.
    Wheat, Phillip
    Institute for Transport Studies, University of L eeds.
    The marginal cost of railway track renewals: a sample selection modelling approach2010Rapport (Annet vitenskapelig)
    Abstract [en]

    Economic theory advocates marginal cost pricing for efficient utilisation of transport infrastructure. A growing body of literature has emerged on the issue of marginal infrastructure wear and tear costs, but the majority of the work is focused on costs for infrastructure maintenance. Railway track renewals are a substantial part of an infrastructure manager’s budget, but in disaggregated statistical analyses, they cause problems for traditional regression models since there is a piling up of values of the dependent variable at zero. Previous econometric work has sought to circumvent the problem by aggregation in some way. In this paper we work with disaggregate (track-section) data, including the zero observations, but apply censored and sample selection regression models to overcome the bias that would result from estimation using OLS. We derive track renewal cost elasticities with respect to traffic volumes and in turn marginal renewal costs using Swedish railway renewal data over the period 1999 to 2009. Our paper is the first paper in the literature that we are aware of to report usage elasticities specifically for renewal costs and therefore adds important new evidence to the previous literature where there is a paucity of studies on renewals and considerable uncertainty over the effects of rail traffic on renewal costs. In the Swedish context, we find that the inclusion of marginal track renewal costs in the track access pricing regime, which currently only reflects marginal maintenance costs, would add substantially to the existing track access charge.

    Fulltekst (pdf)
    fulltext
  • 40.
    Andersson, Olle
    Statens väg- och transportforskningsinstitut.
    Bestämning av vägkonstruktioners egenskaper genom upprepad belastning1970Rapport (Annet vitenskapelig)
    Abstract [sv]

    Vid dimensionering av vägkonstruktioner med ekvationer som tillkommit på grundval av elasticitetsteorin är den dominerande materialparametern av naturliga skäl elasticitetsmodulen hos de i konstruktionen ingående elementen. Undergrundens och de olika skiktens egenskaper mätes detta sammanhang vanligen genom plattbelastning. Denna tillgår så att en på markytan anbringad cirkulär platta belastas med vertikala krafter enligt något på förhand givet system, och motsvarande nedsjunkning hos plattan bestämmes, vanligen med mätur. Om materialet vore idealt elastiskt, skulle elasticitetsmodulen erhållas ur kvoten mellan anbringad kraft på plattan och den därvid uppmätta nedsjunkningen hos plattan, och denna kvot skulle vara oberoende av kraften och av det använda belastningsschemat. På grund av de icke ideala egenskaperna hos vägbyggnadsmaterial bestämmas modulvärdet ur kvoten mellan en på förhand vald kraft och den "elastiska" nedsjunkningen det föreskrivna belastningsschemat.

    Fulltekst (pdf)
    fulltext
  • 41.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Johannesson, Mikael
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Gustafsson, Mats
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Järlskog, Ida
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Lithner, Delilah
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Polukarova, Maria
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Strömvall, Ann-Margret
    Chalmers University of Technology.
    Microplastics from tyre and road wear: a literature review2020Rapport (Annet vitenskapelig)
    Abstract [en]

    This literature review concerns microplastics from tyre and road wear caused by road traffic. As there is limited knowledge about microplastics in general, and microplastics from road traffic in particular, the Swedish Government commissioned the Swedish National Road and Transport Research Institute (VTI) to, during 2018-2020, develop and disseminate knowledge about microplastics from road traffic. The chapters in this report summarises existing knowledge about microplastics from road traffic with respect to the following aspects: sources, spread and presence; effects on and risk to the environment and human health; characteristics and chemical composition; tyre and road wear; sampling methods; analysis and sample preparation; and measures. The report also includes a chapter with overall conclusions, and a chapter about further research, development and investigation needs.

    The purpose of this report is to provide a basis for reducing the generation and spread of microplastics from road traffic. One aim of the report is to collate and disseminate knowledge about microplastics generated by tyre and road wear, and to review the current level of knowledge. A second aim is to identify knowledge gaps and research requirements in relation to microplastics from road traffic. This literature review is based on a review of scientific articles and reports, as well as technical literature and some information from experts and industry.

    Fulltekst (pdf)
    fulltext
  • 42.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Johannesson, Mikael
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Gustafsson, Mats
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Järlskog, Ida
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Lithner, Delilah
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Polukarova, Maria
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Strömvall, Ann-Margret
    Chalmers tekniska högskola.
    Mikroplast från däck- och vägslitage: en kunskapssammanställning2020Rapport (Annet vitenskapelig)
    Abstract [sv]

    Denna kunskapssammanställning handlar om mikroplast från vägtrafikens däck- och vägslitage. Eftersom kunskapen om mikroplaster från vägtrafiken är begränsad samtidigt som däckslitage bedöms vara den största källan till utsläpp av mikroplast i Sverige, gav regeringen inom ramen för sitt arbete med plast och mikroplast Statens väg- och transportforskningsinstitut (VTI) i uppdrag att under 2018– 2020 ta fram och sprida kunskap om mikroplast från vägtrafiken. Varje kapitel i denna rapport sammanfattar befintlig kunskap om mikroplast från vägtrafiken avseende en eller flera aspekter. Dessa aspekter är: källor, spridning och förekomst; miljö- och hälsoeffekter samt risker; egenskaper och kemisk sammansättning; däck- och vägslitage; provtagningsmetoder; analys- och provberedningsmetoder samt åtgärder. Dessutom finns ett kapitel med sammanfattande slutsatser och allra sist ett kapitel om forsknings-, utvecklings- och utredningsbehov.

    Syftet med rapporten är att den ska utgöra ett underlag för att minska emissioner och spridning av mikroplast från vägtrafiken. Ett mål med rapporten är att sammanställa och sprida kunskap om mikroplast från däck- och vägslitage och att redogöra för nuvarande kunskapsläge. Ytterligare ett mål är att identifiera kunskaps- och forskningsbehov avseende mikroplast från vägtrafiken.

    Underlaget till denna kunskapssammanställning utgörs av vetenskapliga artiklar och rapporter samt facklitteratur och information från branschen och från experter.

    Fulltekst (pdf)
    fulltext
  • 43.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Nordin, Lina
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU. VTI.
    SUNRA: Version 20202021Rapport (Annet vitenskapelig)
    Abstract [sv]

    SUNRA (Sustainability: National Road Administrations) SUNRA är ett beslutstödsverktyg som utvecklats för att användas i vägprojekt genom att sätta ambitionsnivå för olika hållbarhetsaspekter och följa upp arbetet mot dessa på ett strukturerat sätt. 

    I detta PM beskrivs hur SUNRA ska användas, följt av ett kapitel med förslag på var i planeringsprocessen SUNRA kan användas. Därefter redovisas de teman och aspekter som beaktas inom SUNRA och underliggande frågeställningar som utgör resultatet av de uppdateringar som gjorts i denna version. 

    I denna version har SUNRA även stämts av mot de globala hållbarhetsmålen liksom Trafikverkets tolkning av dem i form av Målbild 2030. Syftet med SUNRA är att det ska användas för att bidra till en hållbar utveckling med en högre ambitionsnivå än enbart de lagkrav och andra kriterier som måste tas hänsyn till. För de aspekter som beaktas är därför minikrav på målsättning de lagkrav som finns och Trafikverkets egna mål samt policyer.

    Fulltekst (pdf)
    fulltext
  • 44.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ. Chalmers University of Technology, Sweden.
    Nordin, Lina
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Nyberg, Erik
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Johannesson, Mikael
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    A framework for identification, assessment and prioritization of climate change adaptation measures for roads and railways2021Inngår i: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 18, nr 23, artikkel-id 12314Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Severe accidents and high costs associated with weather-related events already occur in today’s climate. Unless preventive measures are taken, the costs are expected to increase in future due to ongoing climate change. However, the risk reduction measures are costly as well and may result in unwanted impacts. Therefore, it is important to identify, assess and prioritize which measures are necessary to undertake, as well as where and when these are to be undertaken. To be able to make such evaluations, robust (scientifically based), transparent and systematic assessments and valuations are required. This article describes a framework to assess the cause-and-effect relationships and how to estimate the costs and benefits as a basis to assess and prioritize measures for climate adaptation of roads and railways. The framework includes hazard identification, risk analysis and risk assessment, identification, monetary and non-monetary evaluation of possible risk reduction measures and a step regarding distribution-, goal-and sensitivity analyses. The results from applying the framework shall be used to prioritize among potential risk reduction measures as well as when to undertake them.

    Fulltekst (pdf)
    fulltext
  • 45.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Nordin, Lina
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Polukarova, Maria
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ. 560625-7813.
    Sunra: version 20212022Rapport (Annet vitenskapelig)
    Abstract [sv]

    Sunra (Sustainability: National Road Administrations) är Trafikverkets beslutstödsverktyg som utvecklats för att användas i väg- och järnvägsprojekt genom att sätta ambitionsnivå för olika hållbarhetsaspekter och följa upp arbetet mot dessa på ett strukturerat sätt. 

    I detta PM beskrivs hur Sunra ska användas, följt av ett kapitel med förslag på var i planeringsprocessen Sunra kan användas. Därefter redovisas de teman och aspekter som beaktas inom Sunra och underliggande frågeställningar som utgör resultatet av de uppdateringar som gjorts i denna version. 

    I denna version har Sunra även stämts av mot de globala hållbarhetsmålen liksom Trafikverkets tolkning av dem i form av Målbild 2030. Syftet med Sunra är att det ska användas för att bidra till en hållbar utveckling med en högre ambitionsnivå än enbart de lagkrav och andra kriterier som måste tas hänsyn till. För de aspekter som beaktas är därför minikrav på målsättning de lagkrav som finns och Trafikverkets egna mål samt policyer. 

    Detta PM är en sammanställning av den senaste versionen av Sunra som innefattar ett större anpassnings- och uppdateringsarbete av Sunra version 2018-11-151 inom ramen för delprojekt 1.12 Sustainable analysis for smart maintenance i programmet Mistra Inframaint. Uppdateringen har gjorts för att Sunra ska kunna användas både inom investerings samt drift- och underhållsprojekt. Uppdateringar har gjorts både med avseende på de aspekter som beaktas inom de olika Temana, vilka Teman olika aspekter beaktas inom samt för att stämma med pågående arbetssätt inom Investera och Drift och Underhåll på Trafikverket. I arbetet med uppdateringen har experter från Drift och Underhåll samt Investering medverkat.

    Fulltekst (pdf)
    fulltext
  • 46.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Nordin, Lina
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Polukarova, Maria
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Afridi, Muhammad Amjad
    Skellefteå kommun; KTH.
    Erlingsson, Sigurdur
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Nyberg, Erik
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Sunra för lokal och regional infrastruktur: prototypen Sulri : Version 20222022Rapport (Annet vitenskapelig)
    Abstract [sv]

    Sunra (Sustainability: National Road Administrations) är Trafikverkets beslutstödsverktyg som utvecklats för att användas i väg- och järnvägsprojekt genom att sätta en ambitionsnivå för olika hållbarhetsaspekter och följa upp arbetet mot dessa på ett strukturerat sätt. 

    I denna avrapportering beskrivs resultatet av fortsatt utveckling av Sunra anpassat för lokal och regional infrastruktur. Resultatet är prototyperna Sulri (Sustainability Local and Regional Infrastructure) och Sulri-frekvent. Sulri-frekvent är avsett att användas för mer frekventa projekt, som till exempel asfaltering av befintliga gator. Sulri också är tänkt för projekt som är lite mer komplexa såsom att tänka om eller planera nytt som till exempel att förbättra för aktivt resande, att klimatanpassa ett område eller att anpassa en gata, en plats eller ett område efter andra behov. Men Sulri kan i princip användas även för mer frekventa eller mindre projekt. I denna rapport beskrivs en första version av Sulri. Rapporten visar på hur verktyget ska användas. Därefter redovisas i kapitel 3 de teman och aspekter som beaktas inom Sulri och underliggande frågeställningar som utgör resultatet av de uppdateringar som gjorts i denna version. I bilaga 2 ges motsvarande redovisning för Sulri-frekvent. I bilaga 1 redovisas relevanta underlag för de olika teman och aspekter som beaktas i Sulri.

    Fulltekst (pdf)
    fulltext
  • 47.
    Andersson-Sköld, Yvonne
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Nordin, Lina
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Rosén, Lars
    Chalmers tekniska högskola.
    Polukarova, Maria
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Johannesson, Mikael
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Miljö, MILJÖ.
    Metod och effektsamband för identifiering, bedömning och prioritering av åtgärder för klimatanpassning av vägar och järnvägar: en förstudie2019Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med den förstudie som redovisas i denna rapport var att ta fram grunden för en metod till stöd för Trafikverkets planering av klimatanpassningsåtgärder för väg och järnväg. Rapporten fokuserar på effektsamband för identifiering, bedömning och prioritering av åtgärder för klimatanpassning av vägar och järnvägar. Metoden och resultaten som presenteras i denna rapport är baserade på litteraturstudier och intervjuer med experter inom väg och järnvägsområdet.

    I rapporten beaktas de konsekvenser och risker som förväntas uppkomma till följd av klimatrelaterade händelser, exempelvis den konsekvens som uppstår vid en specifik klimatrelaterad händelse, såsom de konsekvenser som uppstår vid ett specifikt översvämningsdjup, och åtgärder som kan vidtas för att minska sannolikheten för negativa konsekvenser samt de negativa konsekvenserna i sig.

    För att bedöma eller beräkna hur stor risken är krävs kännedom om sannolikheten för att en viss klimatrelaterad händelse ska inträffa under en given period, samt storlek och typ av skada. Skadekostnaden är summan av försenings- och/eller avstängningskostnad som kan innefatta omledningskostnader och kostnader för byte mellan transportslag med mera samt återställningskostnad. Dessutom ingår även skador på människor och miljön som kan uppkomma till följd av händelsen, till exempel vid skred.

    Fulltekst (pdf)
    fulltext
  • 48.
    Andren, Peter
    et al.
    Statens väg- och transportforskningsinstitut.
    Sjögren, Leif
    Statens väg- och transportforskningsinstitut.
    An explanation to the VTI FILTER documents2001Rapport (Annet vitenskapelig)
    Fulltekst (pdf)
    FULLTEXT01
  • 49.
    Andrén, Peter
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Fyrhjulsmodeller för bestämning av vägojämnhet: dokumentation av verksamhet på VTI 2002-–20112012Rapport (Annet vitenskapelig)
    Abstract [sv]

    Normalt beräknas längsgående ojämnheter på svenska vägar med måttet International Roughness Index (IRI). Detta mått beräknas från en längsprofil, och beskriver den ackumulerade rörelsen mellan hjul och chassi (fjäderrörelse) på en kvartsbilmodell. Resultatet redovisas som fjäderrörelse per färdad längd, vanligtvis millimeter per meter. IRI-modellen beskriver endast rörelsen i vertikalled, dessutom med en ganska orealistisk fordonsmodell som alltid går i 80 km/h. Denna rapport redovisar arbetet med att ta fram en så kallad FullCar-modell (möjligtvis helbilsmodell på svenska, men jag fortsätter att använda ”FullCar” som en generellt beteckning i denna rapport) som kan användas för en mer realistisk modellering av ett fordons rörelser under normal färd. Fördelen med en, ur fordonssynpunkt, mer realistisk modell är att man kan konstruera mått som stämmer bättre överens med det som förare och passagerare upplever när de färdas på vägen. Det bör nämnas att det tidigare har visats att det finns en relativt hög korrelation mellan IRI och hur förare och passagerare upplever vägens tillstånd. En FullCar-modell borde dock kunna ge mer detaljerad information om vägytans effekt på fordonet. Till exempel skulle en lastbilsmodell kunna detektera avsnitt med farliga tvärfall. En realistiskt fordonsmodell skulle även kunna användas till nedbrytningsstudier av vägar, där vägytan dels slits av överfarter, dels deformeras av kontaktkrafter. Med en enkel modell skulle hundratusentals överfarter kunna simuleras på några minuter.

    Fulltekst (pdf)
    FULLTEXT01
  • 50.
    Andrén, Peter
    Statens väg- och transportforskningsinstitut.
    Power spectral density approximations of longitudinal road profiles2006Inngår i: International Journal of Vehicle Design, ISSN 0143-3369, E-ISSN 1741-5314, Vol. 40, nr 1-3, s. 2-14Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The power spectral density (PSD) representation of road profiles can be used both to assess the road roughness, and as an input to vehicle dynamics. The PSD is often approximated with a simple function, using only a few parameters. The present paper presents a literature survey of such PSD approximations, and tests four approximations on longitudinal road profile data from the entire Swedish state road network.

1234567 1 - 50 of 1344
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf