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  • 1.
    Ahmed, Abubeker
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Lundberg, Thomas
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Utvärdering av gummiasfalt: provväg E22 Mönsterås : etapp 12019Report (Other academic)
    Abstract [en]

    Laboratory and filed investigations have been carried out to evaluate the performance of rubber modified asphalt test road on E22 Mönsterås.

    The laboratory investigations indicated that there are no significant differences in stiffness and shear modulus between the reference and rubber modified mixtures. The rubber modified mixture however showed slightly lower phase angle compared to the reference mixture which indicate that the rubber modified mixture is more elastic. The rubber modified mixtures also showed lower modulus at lower temperatures and slightly higher modulus at higher temperature which are desired properties for resistance against low temperature cracking and permanent deformation respectively. The fatigue tests indicated that the rubber modified asphalt mixture has slightly better fatigue cracking performance. But the difference is not significant.

    The road surface profile measurements indicated no significant differences between the reference and asphalt rubber sections. It is however early to draw conclusions after one year of traffic therefore additional follow-up of the test sections is needed to draw a conclusion.

  • 2.
    Ahmed, Abubeker W
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Said, Safwat F.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Lu, Xiaohu
    Nynäs AB.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Pavement performance follow-up and evaluation of polymer-modified test sections2018In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, p. 1-14Article in journal (Refereed)
    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.

  • 3.
    Carlson, Håkan
    Swedish National Road and Transport Research Institute.
    ESWL-beräkningar för några vanliga flygplanstyper på svenska flygfältskonstruktioner2000Report (Other academic)
  • 4.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Beskrivning av VTI-metod för bärighetsklassificering av svenska flygfältsbanor2004Report (Other academic)
    Abstract [sv]

    Bärighetsklassificering av flygfältsbanor enligt det internationella systemet

    med ACN/PCN (Aircraft Classification Number/Pavement Classification Number)

    används dels för att fastställa banors strukturella tillstånd och dels som

    ett operativt mått på en banas trafikerbarhet. Kraven på flygfältsbanorna har

    ökat i takt med större och tyngre flygplan samtidigt som de ekonomiska

    resurserna är begränsade. Det ställer krav på bra analysmetoder för underhåll

    och byggande. Bärighetsklassificeringen är en viktig parameter i

    uppföljningen av banornas tillstånd och underhållsplaneringen av

    flygfältsbanor. Den nuvarande analys- och beräkningsmetodiken har använts

    under många år och det finns en lång erfarenhet av dess användning. Samtidigt

    har ny kunskap successivt tagits fram inom området bärighet på vägar och

    flygfält. Det kan därför finnas ett behov av att uppgradera metoden.

    Tillämpningen av den nedan beskrivna metoden bör ske med viss försiktighet

    och i samråd med bärighetsexpertis. Metoden för bärighetsklassificering

    följer huvudsakligen ett omvänt dimensioneringsförfarande med ett underlag

    bestående av mer eller mindre kända uppgifter om banornas konstruktiva

    utformning (överbyggnadsdata) och en provbelastning med

    fallviktsdeflektometer (fallviktsmätning). Mätningen kan vid behov

    kompletteras med materialprovning i laboratorium.

  • 5.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Bärighetsklassificering av flygfältsbanor. Etapp 1. Inledande parameterstudie1992Report (Other academic)
  • 6.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Bärighetsklassificering av flygfältsbanor: etapp 2. Uppgradering av beräkningsparametrar1996Report (Other academic)
  • 7.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Funktionsbaserad optimering av vägöverbyggnad: uppföljning av provsträckor på E4 Skånes Fagerhult2011Report (Other academic)
    Abstract [en]

    The aim of the project is to explore a concept based on performance optimization of road pavement structures with various fractions of subgrade layer and asphalt pavement thickness.

    The project has a total of 14 test sections located in K1 and K2 in the northbound direction on road E4 between Skånes Fagerhult and Markaryd. These were observed with measurements 2004 to 2010. The follow-up was effected by cross profile measurements and falling weight measurements.

    The follow-up was carried out on 8 test sections á 100 m and 6 test sections á 40 m. The asphalt pavement in the right (slow) lane consists of 40 mm wearing course, 45 mm bitumen base course and 95 mm bitumen roadbase with 80 mm gravel roadbase beneath. The asphalt pavement in the left (fast) lane has the same wearing and bitumen base course but not any bitumen roadbase. The subbase vary between the sections from 60 cm crushed rock 0-300 mm to 42 cm crushed rock 0-150 mm or crushed rock 0-90 mm. All the test sections are situated on embankment of varied height.

    The road was opened for traffic in 2004, but was then trafficked on the bitumen base course. The wearing course was constructed late in summer 2005 after about one year of traffic. The road served 4 years until the summer of 2009 when the wearing course of the right lane was maintained with a remixing. In the left lane no maintenance was done.

    The first measurement at the test sections with the new wearing course was conducted in the spring of 2006 after it had been in service approximately 1 year. In spring 2009 a profile measurement was done before the maintenance operation. The latest profile measurement was carried out in autumn 2010. The rut depth has been calculated according the thread principle.

  • 8.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Förstärkningslagermaterial av krossad betongslipers: provsträckor på väg 869 vid Stenstorp. lägesrapport 20012001Report (Other academic)
  • 9.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Jämförelse av VTIs olika FWD-utrustningar1992Report (Other academic)
  • 10.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Livslängd på markstenskonstruktioner vid trafikbelastning2003Report (Other academic)
    Abstract [sv]

    På uppdrag av Cementa AB har VTI utfört beräkningar av den teoretiska livslängden på överbyggnader med marksten med hänsyn till trafikbelastning. Uppdraget är en fortsättning på tidigare livslängdsberäkningar som utförts och som finns redovisade i VTI notat 49-2001 ”Livslängdsberäkningar på markstenskonstruktioner.” Beräkningarna syftar till att ta fram ett dimensioneringsunderlag för vägöverbyggnader och industriplaner med marksten. Beräkningar har gjorts utifrån tre grundkonstruktioner där sedan tjockleken på förstärkningslagret har varierats med hänsyn till terrassmaterial.

  • 11.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Livslängdsberäkningar på markstenskonstruktioner2001Report (Other academic)
  • 12.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Livslängdsberäkningar på vägöverbyggnader med marksten1999Report (Other academic)
  • 13.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Profilmätning på sträckor med gummimodifierat bitumen på E4 Uppsala och E6 Mölndal: uppföljning efter tre års trafik2015Report (Other academic)
    Abstract [en]

    On behalf of the Swedish Transport Administration, VTI has performed transverse profile measurements and wear measurements on test sections with rubber modified asphalt pavements on E4 Uppsala, Rv77 Knivsta and E6 Mölndal. The purpose of the surveys is to evaluate the different types of wearing course regarding rutting and wear of studded tires and durability / stripping (loss of surface aggregate). The conclusions of the results of the measurements so far do not show any beneficial effects of the modification with rubber in bituminous wearing course, instead these sections have performed worse than the reference section with standard bitumen during the first almost three years. The measured profiles from E4 Uppsala and E6 Mölndal showed an obvious rutting from wear on the surface during all three winter periods. The wear is less clear on the sections on Rv77 Knivsta because of the broader cross road surface and lower traffic intensity. On most test sections, it is a relatively small spread in the propagation of wear between the measured profiles within each test section. Within a few sections, however, the spread is slightly larger and it looks mostly like to apply sections of GAP on E4 Uppsala.

  • 14.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Profilmätning på sträckor med polymermodifierat bitumen på riksväg 47 Falköping: uppföljning efter tre års trafik2015Report (Other academic)
    Abstract [en]

    On behalf of the Swedish Transport Administration VTI has performed transverse profile measurements and wear measurements on test sections with polymer modified asphalt pavements on road 47 at Falköping. The purpose of the surveys is to evaluate the different types of wearing course regarding rutting and wear of studded tires and durability / stripping (loss of surface aggregate). Within the rehabilitation project for the road 2011 test sections with various types of surface course where constructed where six test section of 200 meter long was selected for further evaluation. The monitoring of these test sections include, in addition to test sections with polymer modified bitumen type Nypol and Inormix also connecting reference sections with conventional asphalt paving with standard bitumen (std) B70/100. The amount of traffic, AADT, on the test sections is about 4 500–5 000 vehicles. Profile measurements have been conducted annually from 2011 until the spring of 2014. On each test section was wearing of studded tires measured in 5 transverse profiles and profile measurement for rutting with equipment Primal in 10 transverse profiles and measurement of durability / stripping of 1 m2 over the left wheel track and the edge of the track.

  • 15.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Prov med krossad betong på Stenebyvägen i Göteborg: lägesrapport 20012001Report (Other academic)
    Abstract [sv]

    Inom ramen för projektet "Samverkan för ekologisk stadsförnyelse" har VTI av

    SABEMA Material AB i Göteborg fått i uppdrag att tekniskt utvärdera ett

    försök där krossad rivningsbetong används som förstärkningslagermaterial i

    vägöverbyggnad som ersättning för konventionellt ballastmaterial av krossat

    berg. Försöket är förlagt till Stenebyvägen i Göteborg.

    Ett flertal olika prov med att använda krossad betong i vägöverbyggnad

    respek-tive underbyggnad har tidigare gjorts i Sverige med lyckat resultat.

    Stenebyvägen är emellertid unik på det sättet att vad vi vet

    har det aldrig tidigare lagts krossad betong på en underbyggnad bestående av

    lätt bergbank.

    I det här VTI notatet redovisas resultatet och analysen efter två mätningar

    med fallviktsdeflektometer och tvärprofilmätare Primal som är utförda 2000

    och 2001.

  • 16.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Provväg riksväg 26 Skultorp: uppföljning av provsträckor med aktiv design2016Report (Other academic)
    Abstract [en]

    VTI has performed falling weight measurements and analysis of surface profile measurements on road 26 at Skultorp south of Skövde. Within the road project it was built three test sections (incl. reference section) with different subbase material and an additional section with thinner asphalt pavement for analysis of active design and 1 + 2 sections for monitoring the reference structure constructed of three different contractors. The measurements intended to assess the different construction types and performance by analyzing the differences and changes in stiffness and rutting under 9 years of traffic, for traffic from 2005 to 2014.

    Generally the results of falling weight measurements show a road with very high bearing capacity. There is a big difference in the measurement results and stiffness between the survey before opening for traffic in 2005 and the second measurement 2014, where there was a significantly lower stiffness 2005 than in 2014. At the measurement 2014 it was full asphalt thickness and at the same time the road has consolidated and become compact over many years of service. Therefore, the measurement 2014 best represent the road condition over the years it has been in use.

  • 17.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Vägavsnitt med hyttsten och hyttsand: inventering genom provbelastning2008Report (Other academic)
    Abstract [sv]

    Under många år har hyttsten och hyttsand använts som fullgoda alternativa byggnadsmaterial i vägar som bär- och förstärkningslager, eller som lättfyllning i underbyggnad. Egenskaperna för de här materialen har tidigare undersökts i laboratorier och i begränsad omfattning i fält och då uppvisat goda resultat. Syftet med det här projektet är i första hand att genom provbelastning med FWD på ett flertal vägobjekt i Sörmland, som har uppbyggnader med lager som består av hyttsten eller hyttsand, undersöka materialens egenskaper och funktion i vägen. Detta kan sedan ligga till grund för dimensioneringen av vägar med lager av hyttsten och hyttsand. För undersökningen valdes fem vägavsnitt ut samt ett avsnitt på en gång- och cykelbana, samtliga belägna i Sörmland. De utvalda avsnitten har hyttsten eller hyttsand i konstruktionen. I notatet redovisas även resultat från tidigare undersökningar som gjorts på Rv 52:01 Katrineholm och som är väldokumenterade. För att jämföra de olika sträckorna är det önskvärt att kunna beräkna de olika lagrens styvhet (E-modul). Då uppgifter om lagertjocklekar saknades på flertalet av sträckorna är det inte möjligt att beräkna styvheten, varför andra beräknade mått får användas. De beräknade bärighetsmått som används i jämförelsen är "Uppskattad undergrundsmodul" och "Uppskattad beläggningstöjning" enligt Vägverkets metodbeskrivning 114:2000.

  • 18.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Årstidsvariation i materialstyvheter hos icke normenligt byggda vägar2000Report (Other academic)
  • 19.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 1: Mätningar och bearbetningar av data1991Report (Other academic)
  • 20.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 10: Data från väg 720 19871991Report (Other academic)
  • 21.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 2: Data från väg 34 19851991Report (Other academic)
  • 22.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 3: Data från väg 34 19861991Report (Other academic)
  • 23.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 4: Data från väg 34 19871991Report (Other academic)
  • 24.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 5: Data från väg 234 19851991Report (Other academic)
  • 25.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 6: Data från väg 234 19861991Report (Other academic)
  • 26.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 7: Data från väg 234 19871991Report (Other academic)
  • 27.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 8: Data från väg 720 19851991Report (Other academic)
  • 28.
    Carlsson, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Jansson, Håkan
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Provbelastning av instrumenterade vägar: Deformationsdata från mätningar på väg nr 34, 234 och 720 i Sverige 1985-87. 9: Data från väg 720 19861991Report (Other academic)
  • 29.
    Djärf, Lennart
    et al.
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    A new flexible pavement design method: Formulation of a user-friendly mechanistic/empirical design system for Swedish conditions1996Report (Other academic)
  • 30.
    Djärf, Lennart
    et al.
    Swedish National Road and Transport Research Institute.
    Wiman, Leif G
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Dimensionering vid nybyggnad: utformning av ett användarvänligt mekanistiskt/empiriskt dimensioneringssystem för svenska förhållanden1996Report (Other academic)
    Abstract [en]

    Pavement design means selecting materials and determining layer thicknesses so that the road fulfils the performance requirements for a chosen period. Mechanistic design methods make it possible to adapt designs to the particular conditions. The need for a flexible design system is motivated by the development of vehicles and especially tyres (increased inflation pressure and wide base tyres). In recent years, development has taken a direction that is unfavourable in regard to road wear.

    An expected increase in usage of secondary and recycled road materials in the future is a further motive for a flexible design system. Work on developing a flexible design system for Swedish conditions has been commissioned by the Swedish National Road Administration and was carried out during the period 1987-1994. The result is described in this report. The aim of the project was to develop a user-friendly and flexible design system for road pavements which is suitable for Swedish conditions.

    The following three principle sections are required for the calculation of the bearing capacity of road pavements based on a mechanistic approach:

    •- A calculation method for the determination of stresses and strains in the road structure.

    •- Knowledge of the mechanical properties of the road building materials and of the subgrade, primarily stiffnesses or resilient moduli.

    •- Design criteria or design values for the stresses and strains that are critical for the bearing capacity of the road structure.

  • 31.
    Erlingsson, Sigurdur
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Testplatser för 74 ton tunga fordon: två instrumenterade tunna vägkonstruktioner2018Report (Other academic)
    Abstract [en]

    This VTI note describes briefly the construction and instrumentation of two new test road structures that have been built during the autumn 2017 on Lv373 and Lv515 respectively in Norrbotten County in northern Sweden. One structure is placed on Lv373 east of the village Långträsk while the other structure is on Lv515 south if the intersection with Lv373. The distance between the two locations is about 10 km. Both structures are thin pavement structures. The main objective of the two new test sites is to estimate the impact that the new 74 tonnes vehicles have on the Swedish road network. This will be done through direct measurements of the pavement response from the road sensors. The sensors consist of horizontal strain sensors in both longitudinal and transversal direction at the bottom of the asphalt layer as well as vertical strain sensors over every layer down to 1.2 m depth. Soil pressure cells are further installed at two depths. The local ambient climate is monitored as well. A frost and a moisture rod were therefore installed. Further are temperature sensors installed in the asphalt concrete. Two weather stations are located within 20 km distances from the test structures. The first response measurements are planned in the late summer or early autumn 2018.

  • 32.
    Erlingsson, Sigurdur
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    The Svappavaara road test sections: instrumentation2014Report (Other academic)
    Abstract [en]

    This report describes four new instrumented test road sections that have been built on E45 close to the Svappavaara in Norrbotten County in Northern Sweden. The structures are located about 100 km north of the Arctic Circle in a climate that is characterized by long cold winters and short mild summers. Norrbotten County is a sparsely populated area where the pavement structures consist of thin pavements with relatively low traffic volume. A new ore deposit, the Kaunisvaara project, was opened in 2012, meaning that the ore will be transported along the existing road network about 160 kilometers to where it will be transferred to a railway. The ore operator has received a permit to use 90 ton vehicles instead of the permissible 60 tons, consisting of a single wheel steering axle and triple dual wheel tridem axles to transport the iron ore. When the ore processing will be in full operation around 66.000 journeys per year will pass over the network, or on average about 7–8 passes per hour with about seven and a half minutes between the passes. Due to this new ore transport it will be necessary to strengthen the local road network. As part of the process to evaluate the performance of a suitable pavement structure these four instrumented test road structures have been selected and built. The structures are instrumented with road performance and climate sensors. The structures will be monitored over the years to come, though the details of the monitoring programme have not yet been decided. Each test section is around 200 metres long, consisting of a 100 metres long inner part that constitutes the intrinsic test section. The structures were built and instrumented in the summer of 2012 except for the wearing course that was placed in the summer of 2013 along with the temperature sensors that are placed in the asphalt layers. The instrumentation in each section consists of Emu coils for vertical strain measurement devices, soil pressure cells for vertical stress measurements and tensile strain gauges located at the bottom of the bound road base layer. In addition there are moisture rods located in three of the structures and a temperature (frost) rod located in structure 3. A weather station (2527 Svappavaara) operated by the Transport Administration is located 3.2 kilometre south-east of the test site.

  • 33.
    Höbeda, Peet
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Hermelin, Klas
    Swedish National Road and Transport Research Institute.
    Hornwall, Fredrik
    Swedish National Road and Transport Research Institute.
    Viman, Leif
    Swedish National Road and Transport Research Institute.
    Undersökning av vägskador på väg E18, delen Köping - Arboga1999Report (Other academic)
  • 34.
    Lindh, Einar
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Armering med geonät vid förstärkning av väg: Prov vid Backe 1990. Slutrapport1994Report (Other academic)
  • 35.
    Lindh, Einar
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Armering och stabilisering av sand i bärlager vid förstärkning av väg: prov vid Sunne 19881993Report (Other academic)
  • 36.
    Lindh, Einar
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Viman, Leif
    Swedish National Road and Transport Research Institute.
    Armering och stabilisering av sandlager vid förstärkning av väg1991Report (Other academic)
  • 37.
    Lu, Xiaohu
    et al.
    Nynäs AB.
    Said, Safwat
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Soenen, Hilde
    Nynas NV.
    Heyrman, Serge
    Nynas NV.
    Redelius, Per
    Nynäs AB.
    Performance Evaluation of Polymer Modified Bitumens on a Heavily Trafficked Test Road2014In: International Journal of Pavement Research and Technology, ISSN 1997-1400, Vol. 7, no 6, p. 381-388Article in journal (Refereed)
    Abstract [en]

    In asphalt paving, polymer modified bitumens (PMBs) have more potential for use and can clearly demonstrate the value of their initial higher cost. To further assess the sustainable benefits of using PMBs, a test road was constructed on a highway in Sweden. In this paper, the asphalt binders used were investigated extensively using rheological and chemical methods, and asphalt field cores characterized with respect to permanent deformation and fatigue. It was found that the modified binders, particularly with SBS polymers, retain better rheological properties in comparison with conventional ones, even after several years in the field; these include higher strain recovery and lower non-recoverable compliance at high temperatures, and lower stiffness at low temperatures. The SBS modified binders also demonstrate good aging resistance, shown by both laboratory aging tests and field aging. the high resistance to aging for the SBS modified binders was also evident in the stiffness measurement made on asphalt field cores. Moreover, the modified binders with SBS polymers significantly enhance fatigue behaviour.

  • 38.
    Lu, Xiaohu
    et al.
    Nynas AB.
    Said, Safwat F.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Soenen, Hilde
    Nynas NV.
    Heyrman, Serge
    Nynas NV.
    Redelius, Per
    Nynas AB.
    Evaluation of test sections with Polymer Modified Bitumens2014In: Asphalt Pavements: Proceedings of the International Conference on Asphalt Pavements, ISAP 2014, 2014, p. 287-296Conference paper (Refereed)
    Abstract [en]

    It has been recognized that Polymer Modified Bitumens (PMB) have more potential for use in asphalt paving and can clearly demonstrate the value of their initial higher cost. To further assess sustainable benefits on heavy trafficked roads, test sections using various PMBs were built on highway E6 in Sweden during 2003-2006. The main objective of this paper is to study the aging and rheological properties of the binders used. A large number of cores were drilled and characterized with respect to stiffness, fatigue and permanent deformation. The binders (original, lab aged and recovered) were investigated extensively with rheological and chemical methods. It was found that PMBs, particularly SBS modified, demonstrate better rheological properties as compared to unmodified bitumens, even after several years in the field. These include higher strain recovery and lower non-recoverable compliance at high temperatures, and lower stiffness at low temperatures. For the SBS modified binders, good aging resistance was observed. The high resistance to aging for the SBS modified binders was also evident in the stiffness measurement made on asphalt field cores. Although significant differences have not yet been seen between the test sections (all the sections are in good condition after six years of traffic), the observed improvements for the modified binders are expected to be confirmed by a longer follow-up of the test road.

  • 39.
    Saevarsdottir, Thorbjorg
    et al.
    University of Iceland.
    Erlingsson, Sigurdur
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology. University of Iceland.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Heavy Vehicle Simulator tests at VTI2014In: Asphalt Pavements - Proceedings of the International Conference on Asphalt Pavements, ISAP 2014, 2014, p. 823-833Conference paper (Refereed)
    Abstract [en]

    Flexible test road structures have been built and tested in Accelerated Pavement Tests (APT) using a Heavy Vehicle Simulator (HVS) at VTI in Sweden for 15 years. The objectives have been to investigate pavement responses and pavement performance behaviour which can be used to validate mechanistic performance schemes. The pavement structures have been instrumented to measure their responses and performance and the surface profile was estimated.

    The accuracy of the measurements was estimated and a performance prediction was carried out. The registrations of the measurements were rather smooth with good repeatability and acceptable accuracy. The response, performance and accumulation of permanent deformation were modelled and generally good agreement was established between the measurements and calculations. From the analysis a performance prediction can be carried out as a function of time to evaluate the performance of new road concepts and maintenance strategies. The performance prediction provides the option of performing a life cycle cost analysis which can decrease both costs and environmental impacts.

  • 40.
    Saevarsdottir, Thorbjorg
    et al.
    University of Iceland.
    Erlingsson, Sigurdur
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology. University of Iceland.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Instrumentation and performance modelling of heavy vehicle simulator tests2016In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 17, no 2, p. 148-165Article in journal (Refereed)
    Abstract [en]

    Flexible test road structures have been built and tested in accelerated pavement tests using a heavy vehicle simulator (HVS) at VTI in Sweden for 15 years. The objectives have been to investigate pavement responses and pavement performance behaviour, which can be used to validate mechanistic performance schemes.

    Here, the instrumentation is described, its accuracy is estimated, the response and performance are modelled and a performance prediction is carried out. The registrations of the measurements were rather smooth with acceptable variation. In general, good agreement was established between the measurements and calculations. The HVS machine can be used to evaluate new road concepts and maintenance strategies and provides the option of performing a life cycle cost analysis, which can decrease both costs and environmental impacts.

  • 41.
    Said, Safwat
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Alternativa bitumenbundna bärlager - provsträckor på E18 Köping: lägesrapport1999Report (Other academic)
    Abstract [sv]

    Nya bitumenbundna bärlagertyper som alternativ till konventionella AG-beläggningar har börjat användas sedan några år. Åtta provsträckor, där 4 olika typer av bitumenbundna bärlager ingår, på E18 Köping har följts upp under ett antal år. Den här lägesrapporten behandlar laboratorieresultat hos borrkärnoroch fältmätningar sedan vägens öppnande 1995.

  • 42.
    Said, Safwat
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Johansson, Svante
    Swedish National Road and Transport Research Institute.
    Stålarmering av väg E6 Ljungskile, Bratteforsån-Lyckorna2003Report (Other academic)
    Abstract [sv]

    En sträcka på 800 m av motorvägen E6 söder om Ljungskile

    (Bratteforsån-Lyckorna), öppnad för trafik 1991, uppvisade skador i form av

    längsgående sprickor i hjulspåren redan efter ca 5 års trafikering. En

    skadeutredning utfördes under 1996 och vägsträckan underhölls genom en

    försegling av vägytan på de skadade avsnitten. Det var dock klarlagt redan då

    att det fanns ett förstärkningsbehov. Under år 2000 hade vägen omfattande

    längs- och tvärgående sprickbildning samt visade en omfattande spårbildning

    med ojämnheter. Under år 2000 förstärktes sträckan genom fräsning och

    påbyggnad inklusive armering med stålnät. Inom vägavsnittet anlades tre

    provsträckor för undersökning av stålnätsarmeringens betydelse för upphöjning

    och förbättring av bärigheten och motståndet mot sprickor och spår. Denna

    rapport beskriver dessa sträckor samt redovisar resultat från uppföljning

    under tre år. Det här är det första svenska försöket med stålarmerad väg där

    uppföljningen skett med töjningsgivare i vägkonstruktionen. Syftet med

    projektet i Ljungskile är att studera stålnätets förmåga att ge ökad bärighet

    i vägkroppen och motverka sprickor och spårbildning i beläggningsytan.

    Uppföljning med fallviktsmätningar visar inga nämnbara skillnader mellan

    provsträckorna. Resultaten från töjningsgivarna i asfaltbeläggningen däremot

    gav stora skillnader i töjningsnivå mellan provsträckorna. De största

    töjningarna uppmättes på referenssträckan. Armerade sträckor uppvisade

    betydligt lägre töjningar. Spårdjupsmätningarna med Primal visade hittills på

    liten spårbildning och inga tydliga skillnader mellan provsträckorna. Om

    tendensen till spårutveckling fortsätter kommer de båda stålarmerade

    konstruktionerna uppvisa en något lägre spårbildning än referenssträckan.

    Vägen har ännu bara trafikerats två år efter förstärkningsåtgärden och den

    fortsatta utvecklingen är av största intresse att följa!

  • 43.
    Said, Safwat F
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Samband mellan fält- och laboratoriemoduler1995Report (Other academic)
  • 44.
    Said, Safwat F
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Hakim, Hassan
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Förstärkning av vägkonstruktion med stålnätsarmering: 12 års uppföljning av väg E6 Ljungskile2014Report (Other academic)
    Abstract [en]

    A motorway road section of 800 metre long of the road E6 south of Ljungskile in the Southwest of Sweden was seriously damaged due to low bearing capacity. Longitudinal and transversal cracks were frequently observed after about five year’s traffic. The road section was rehabilitated by milling away 80 millimetre and paving with new bituminous layers. Three full-scale, 100-metre test sections were built. Two test sections were reinforced with steel fabrics and one section without reinforcement as a reference section. These sections are instrumented with strain gauges. The section’s performance have been tested by deflection, strain and rut measurements and manual distress surveys. Degradation behavior of the test sections were numerically analyzed. This report presents pavement performance of the test sections after 12 years in-service. The reference section has shown extensive longitudinal cracks in the wheel paths. However, almost no cracks in the reinforced sections. It is concluded that the reinforcement had a significant influence (10–15%) in increasing the resistance of the test sections against fatigue cracking and in limitation of the rutting in pavement surface related to repeated-loading of the heavy vehicles.

  • 45.
    Said, Safwat F.
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Lundberg, Thomas
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Rahman, Shafiqur
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    McGarvey, Terence
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Ahmed, Abubeker
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Enocksson, Carl-Gösta
    Trafikverket.
    Utförandets inverkan på hållbarhet för beläggningslager2019Report (Other academic)
    Abstract [en]

    Non-destructive testing in quantifying the asphalt pavement layers homogeneity can be used for the quality assurance in paving contracts. This paper summarizes the findings from a field study on segregation in bituminous pavement mixes that relates pavement layer surface texture to the homogeneity of the paved bituminous layer by distinguishing mix segregated area. The mean profile depth (MPD) values of paved layer were measured. Based on these values three locations on the road were identified having low, intermediate and high MPD values. Thereafter, cored samples were tested for stiffness modulus before and after moisture conditioning by performing the moisture induced sensitivity test (MIST). Results clearly showed that the samples from the locations with high MPD values were mostly affected by the moisture conditioning for which the stiffness moduli were significantly reduced. The samples with high MPD values had the highest air voids as well. Thus, this study demonstrated that construction quality described by segregation in the paved asphalt mix has a significant impact on the moisture sensitive performance of pavements. A limited number of falling weight deflectometer (FWD) measurements were performed at positions with different degree of separation in the road base layer. There was a tendency for the effect of separation in the road base layer on FWD even though there was a variation in data. The strong correlation between the MPD values and change in stiffness modulus also suggests that the measurements of the MPD values can be a reliable and non-destructive method for evaluating the construction quality of a pavement and in developing the quality assurance criteria based on pavement performance that can be used in paving contracts.

  • 46.
    Said, Safwat Fadil
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute, Infrastructure, Measurement technology and engineering workshop.
    Viman, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Nordgren, Torsten
    Trafikverket.
    Provsträckor med gummiasfalt: Ragn-Sells infart vid granulatanläggningen, Heljestorp2014Report (Other academic)
    Abstract [sv]

    Mer än 150 000 ton gummiasfalt har tillverkats mellan åren 2007–2013 i Sverige för asfaltering av totalt mer än 150 km vägsträckor fördelade på mer än 20 vägobjekt. I det här arbetet redovisas uppbyggnaden och tillståndsutvärderingen av fyra beläggningsytor byggda under hösten 2011 på infarten till Ragn-Sells granulat-anläggning i Vänersborg. Beläggningsytorna är utförda med olika konstruktioner och asfaltbeläggningslager. Syftet är att värdera nyttan med gummiasfalt i olika lager i vägkroppen, främst med avseende på teknisk livslängd. Provytorna har instrumenterats med töjningsgivare i underkant av beläggning. Det konstateras att vägöverbyggnader bestående av gummimodifierat bitumen kan ha betydande positiv inverkan på motstånd mot sprickor baserad på töjningsmätningarna under det första året efter byggandet av provvägen.

  • 47.
    Said, Safwat
    et al.
    Swedish National Road and Transport Research Institute.
    Hermelin, Klas
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Alternativa bitumenbundna bärlager: provsträckor på E18 Köping. Byggnadsrapport1997Report (Other academic)
  • 48.
    Wiman, Leif G
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Viman, Leif
    Swedish National Road and Transport Research Institute.
    Hultqvist, Bengt-Åke
    Swedish National Road and Transport Research Institute.
    Prov med olika överbyggnadstyper: observationssträckor på väg E6, Fastarp-Heberg. resultatrapport efter 7 års uppföljning, 1996-20032005Report (Other academic)
    Abstract [sv]

    I samband med utbyggnaden av väg E6 norr om Halmstad, delen Fastarp-Heberg, valde Vägverket att utföra överbyggnader med olika konstruktiv utformning. VTI har på uppdrag av Vägverket Västra regionen dokumenterat byggandet och följt tillståndsutvecklingen på speciellt utvalda observationssträckor. Vägavsnittet, som är totalt ca 21 km varav 1/3 är utförd med bituminös beläggning och 2/3 med cementbetongbeläggning, öppnades för trafik den 13 november 1996. I föreliggande rapport redovisas resultatet av tillståndsuppföljningen under de sju första åren efter trafikpåsläpp. Uppföljningen är planerad att pågå ytterligare tre år. Så här beskriver Vägverket Västra regionen bakgrunden till provvägen: "Det svenska vägnätet har successivt belastats med allt större laster. Regelverken för utförande har förnyats med jämna mellanrum bl.a. för att konstruktionerna skall klara lasterna. Under ett flertal år har nybyggda vägar utförts som asfaltkonstruktioner. Under senare delen av 1980-talet beslöts att utföra någon nybyggd väg med betongöverbyggnad. De vägar som utfördes med betong var E4 vid Arlanda och E6 söder Falkenberg. Då det stod klart att E6 Fastarp-Heberg skulle byggas ut till motorväg tog regionchefen i västra regionen beslut att detta objekt skulle utföras som provväg dels med betongöverbyggnad dels med asfaltöverbyggnad. Huvudsyftet var att kunna jämföra de olika konstruktionerna mot varandra i ett långsiktigt perspektiv. Det förväntade resultatet är att kunna redovisa säkra skillnader mellan de olika konstruktionerna beträffande: stabilitet, spårslitage, deformationsresistens, underhållskostnader, friktion och buller. Den förväntade nyttan är att med en väl underbyggd uppföljning från projektet kunna planera och investera med de för ändamålet rätta tekniska lösningarna framförallt på de bundna överbyggnadslagren."

  • 49.
    Wiman, Leif G
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Viman, Leif
    Swedish National Road and Transport Research Institute.
    Hultqvist, Bengt-Åke
    Swedish National Road and Transport Research Institute.
    Prov med olika överbyggnadstyper: uppföljning av observationssträckor på väg E6, Fastarp-Heberg. 1996-20062009Report (Other (popular science, discussion, etc.))
    Abstract [en]

    In connection with the construction of a new part of European road 6 (E6) close to the city Halmstad, (section Fastarp-Heberg), the Swedish Road Administration decided to investigate the long term behaviour of different types of pavement structures. VTI got the mission to make documentation during the construction and to follow-up the performance of these pavement structures on selected sections. The total length of this new road was 21 km and 1/3 was constructed with flexible pavement structures and 2/3 with rigid pavement structures (cement concrete). The road section was open to traffic in the autumn 1996. The main objective of the study is to investigate the pavements resistance to rutting, both regarding wear from studied tires and deformation from heavy traffic. The objective is also to study surface characteristics as evenness, friction and noise. This report includes results and analyses from the first 10 years of the study (1996-2006). In summary the conclusions so far are as follows: - Performance based specifications clearly improved the deformation properties of the bituminous bound layers. - Semi-rigid pavement structures showed good resistance to rutting. - Investigation is needed to improve the resistance to reflective cracking of the semi-rigid structures - The vertical position of steel net in reinforced flexible structures is important. A position below a thin wearing course (40 mm) can not be recommended from this study. - More than half of the surface rutting on the flexible structures could be referred to deformation from the heavy traffic and a great deal occurred after the first year. - Rigid pavement sections showed good wear resistance. - The difference in surface friction and noise was small between flexible and rigid pavement sections but regarding noise this was only followed during the first three years of the study.

  • 50.
    Wiman, Leif G (red.)
    et al.
    Swedish National Road and Transport Research Institute.
    Carlsson, Håkan
    Swedish National Road and Transport Research Institute.
    Prov med olika överbyggnadstyper: observationssträckor på väg E6, Fastarp-–Heberg. Resultatrapport efter 5 års uppföljning, 1996-–20012002Report (Other academic)
    Abstract [sv]

    I samband med utbyggnaden av väg E6 norr om Halmstad, delen Fastarp-Heberg,

    valde Vägverket att utföra överbyggnader med olika konstruktiv utformning.

    VTI har på uppdrag av Vägverket Västra regionen dokumenterat byggandet och

    följt tillståndsutvecklingen på speciellt utvalda observationssträckor.

    Vägavsnittet, som är totalt ca 21 km varav 1/3 är utförd med bituminös

    beläggning och 2/3 med cementbetongbeläggning, öppnades för trafik den 13

    november 1996. I föreliggande rapport redovisas resultatet av

    tillståndsuppföljningen under de fem första åren efter trafikpåsläpp.

    Uppföljningen är planerad att pågå ytterligare två år. Så här beskriver

    Vägverket Västra regionen bakgrunden till provvägen: "Det svenska vägnätet

    har successivt belastats med allt större laster. Regelverken för utförande

    har förnyats med jämna mellanrum bl.a. för att konstruktionerna skall klara

    lasterna. Under ett flertal år har nybyggda vägar utförts som

    asfaltkonstruktioner. Under senare delen av 1980-talet beslöts att utföra

    någon nybyggd väg med betongöverbyggnad. De vägar som utfördes med betong var

    E4 vid Arlanda och E6 söder Falkenberg. Då det stod klart att E6

    Fastarp-Heberg skulle byggas ut till motorväg tog regionchefen i västra

    regionen beslut att detta objekt skulle utföras som provväg dels med

    betongöverbyggnad dels med asfaltöverbyggnad. Huvudsyftet var att kunna

    jämföra de olika konstruktionerna mot varandra i ett långsiktigt perspektiv.

    Det förväntade resultatet är att kunna redovisa säkra skillnader mellan de

    olika konstruktionerna beträffande: stabilitet, spårslitage,

    deformationsresistens, underhållskostnader, friktion och buller. Den

    förväntade nyttan är att med en väl underbyggd uppföljning från projektet

    kunna planera och investera med de för ändamålet rätta tekniska lösningarna

    framförallt på de bundna överbyggnadslagren."

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