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  • 301.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: rapportsammanställning av föredrag vid forskardagarna 1996-01-10--111996Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    rapportsammanställning av föredrag vid forskardagarna 1996-01-10--11 beträffande:

    • traffic flow modelling
    • trafikteknik och trafiksäkerhet i tätort
    • barn, trafik och närsamhälle
    • djupstudier av trafikolyckor
    • från väg till gata
    • trafikteori
    • aktuella trafiksäkerhetsfrågor
    • alternativa inriktningar av trafikpolitiken och investeringsplaneringen
    • det nationella trafiksäkerhetsprogrammet
  • 302.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--091997Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--09 beträffande:

    • trafiksäkerhet
    • information och kampanjer
    • utbildning
    • olycksdata
    • trafiksäkerhetsmodeller och variabler
    • tätorternas trafik- och trafiksäkerhetsproblem
    • nollvisionen i ett kommunalt perspektiv
  • 303.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--091997Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--09 beträffande:

    • miljö
    • el & hybridfordon
    • vägar och markmiljö
    • Agenda 21 i godstransportsektorn
    • åtgärder och styrmedel för ett miljöanpassat tranpsportsystem
    • sjöfart: ekonomi, säkerhet och miljö
    • ny teknik: nya möjligheter
    • återvinning: återanvändning
    • asfaltåtervinning
    • biodrivmedel
  • 304.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--091997Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna 1997-01-08--09 beträffande:

    • nordisk modellutveckling inom markanvändning, transporter och miljö 
    • infrastruktur och tågsystem
    • sjöfartens framtid i infrastrukturen
    • underhåll och drift av vägar
    • isolering och beläggning av Höga Kusten-bron
    • transportforskningens nya villkor
    • Dennnispaketet som metodutvecklare
  • 305.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14. Del 21998Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14 beträffande

    trafiksäkerhet - nollvisionen 

    trafiksäkerhet - allmänt

    är det säkert?

    trafikant- och förarutbildning

    trafiksäkerhetsundersökningar i Vägverkets basurval - metodik och resultat

  • 306.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14. Del 3.1998Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14 beträffande:

    underlag för beslut om inriktning av de statliga infrastrukturinvesteringarna

    geoteknisk FoU för infrastruktur - en investering med hög avkastning

  • 307.
    Asp, Kenneth
    Statens väg- och transportforskningsinstitut.
    VTI:s och KFB:s forskardagar: Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14. Del 41998Konferanseproceedings (Annet vitenskapelig)
    Abstract [sv]

    Rapportsammanställning av föredrag vid forskardagarna i Linköping 1998-01-13--14 beträffande:

    väginformatik

    grusvägar

    vägteknik - i går, i dag och i morgon

    människor rörlighet: attityder och resvanor

  • 308.
    Asp, Kåre
    Statens väg- och transportforskningsinstitut.
    Strategic Highway Research Program and traffic safety on two continents in Gothenburg, Sweden, 27-29 September, 1989. Proceedings: Opening. International harmonization of test procedures and requirements for roadside safety features, workshop1990Konferanseproceedings (Annet vitenskapelig)
  • 309.
    Asplund, Disa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Discounting transport infrastructure investments2018Rapport (Annet vitenskapelig)
    Abstract [en]

    The main aim of the study is to advice the Swedish national guidelines on cost-benefit analysis (CBA) of transport infrastructure investments, ASEK about the appropriate set of discount-rates (currently 3.5% for all investments). To this end, first a literature review with a theoretical focus along with some new perspectives are provided. Second the conclusions are applied to Swedish infrastructure transport CBA, using the current proposition of a new HSR line as a case. Based on empirical research concerning parameter values new discount rates are estimated, and sensitivity analysis performed. The best estimate of the social discount rate in the present study, for land transport infrastructure investment in Sweden, is about 5.1%.

  • 310.
    Astner, Linda
    et al.
    Gävle Hamn AB, Gävle, Sweden.
    Carpenter, Angela
    University of Leeds, UK.
    Lozano, Rodrigo
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, Industriell ekonomi. Högskolan i Gävle, Centrum för logistik och innovativ produktion.
    Sammalisto, Kaisu
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, Industriell ekonomi. Högskolan i Gävle, Centrum för logistik och innovativ produktion.
    Utilizing waste to create new port land2018Inngår i: Port Technology, Vol. 77, nr Spring, s. 118-119Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    This paper presents the most recent port expansion and the major dredging and land creation project that has been undertaken in the Port of Gävle since 2007. This project has seen the deepening and widening of the fairway to accommodate larger vessels, as well as the construction of a new cargo terminal area due to open in late 2019. This land creation work has been undertaken using contaminated sediments dredged from deepening the shipping channel.

  • 311.
    Atif, Yacine
    et al.
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Ding, Jianguo
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Lindström, Birgitta
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Jeusfeld, Manfred
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Andler, Sten F.
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Yuning, Jiang
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Brax, Christoffer
    CombiTech AB, Skövde, Sweden.
    Gustavsson, Per M.
    CombiTech AB, Skövde, Sweden.
    Cyber-Threat Intelligence Architecture for Smart-Grid Critical Infrastructures Protection2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Critical infrastructures (CIs) are becoming increasingly sophisticated with embedded cyber-physical systems (CPSs) that provide managerial automation and autonomic controls. Yet these advances expose CI components to new cyber-threats, leading to a chain of dysfunctionalities with catastrophic socio-economical implications. We propose a comprehensive architectural model to support the development of incident management tools that provide situation-awareness and cyber-threats intelligence for CI protection, with a special focus on smart-grid CI. The goal is to unleash forensic data from CPS-based CIs to perform some predictive analytics. In doing so, we use some AI (Artificial Intelligence) paradigms for both data collection, threat detection, and cascade-effects prediction. 

  • 312.
    Atterby, Alfred
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Bluj, Jakub
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Sjögren, Elias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Potential for electric vehicle smart charging station expansion at Fyrisskolan2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of this bachelor thesis is to investigate the potential for electric vehicle charging at the high school Fyrisskolan, located in central Uppsala. The idea relies on charging electric vehicles (EV:s) outside of the hours of peak power consumption of the school which in this report is assumed to be solved by a suitable smart charger. In this project, various stochastic models are built to simulate solar energy production and school energy consumption using data collected from various sources. This generated data along with  driving distances and EV:s energy consumptions are used to calculate the available energy for EV charging. The available energy is then used to distinguish a minimal, mean and maximal amount of cars that could potentially be charged outside Fyrisskolan for each chosen month. The data collected is taken from December, March and June. Calculations and simulations are done in MATLAB. Results show that with available energy outside the peak energy consumption hours, there is a possibility to charge around 104 EV:s in one work day. The main conclusion is that there is not only a big potential to expand the charging of EV:s outside the school by installing smart charging stations in a technical view, but also a desire from employees at the school and neighbours living near it, to charge their future electric vehicles.

  • 313.
    Awan, Hammad Hussain
    et al.
    Hasselt University, Belgium.
    Pirdavani, Ali
    Hasselt University, Belgium.
    Brijs, Tom
    Hasselt University, Belgium.
    Analysis of merging freeways with decreasing number of lanes: a driving simulator study2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The main function of freeways is to provide free flow of traffic at high speeds. Merging of two freeways should therefore be designed in a way that its impact on the free flow of traffic is minimized. There are two possible ways in which merging sections of freeway are designed. First, merging of freeways with same number of lanes (i.e. number of lanes in the merged freeway equals sum of the number of lanes of two merging freeways) and, second merging of freeways with decreasing number of lanes (i.e. number of lanes in the merged freeway is less than the total number of lanes of the merging freeways). In this study, merging with decreasing number of lanes is under consideration.

    To design the merging section of freeways, usually the entire section is divided into three major subsections; ramp, acceleration lane and weaving section. In the Dutch Standards named “Richtlijn Ontwerp Autosnelwegen” along with the design specifications for individual elements of merging section, complete simplified designs are provided for merging sections with decreasing number of lanes for specific vehicle/capacity ratios and design speeds. In this study, we are investigating these designs in relation to the drivers’ behaviour.

    Objectives of this research include: 1) studying drivers’ behaviour while driving through merging designs given in the Dutch Standards and 2) comparing the efficiency of the considered designs under various heavy traffic proportions.

  • 314.
    Axelsson, Erik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Syk, Annelie
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Ülker Kaustell, Mahir
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Battini, Jean-Marc
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Effect of axle load spreading and support stiffness on the dynamic response of short span railway bridges2014Inngår i: Structural Engineering International, ISSN 1016-8664, E-ISSN 1683-0350, Vol. 4, s. 457-465Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In dynamic analyses of railway bridges, the train axle loads are often modeled as moving point forces. However, one effect of the ballast is to spread these point forces. This can lead to large reductions of the bridge response, especially for short span bridges. For this reason, Eurocode prescribes to distribute the axle loads over three adjacent sleepers. In this paper, the axle load distribution is first studied using a plane finite element analysis and based on that, a triangular load distribution is proposed. Then, numerical simulations are performed to compare the effect of this load distribution with the Eurocode one. Both simply supported bridges and bridges with integrated backwalls, all with span lengths less than 10m, are studied. For the later bridges, the effect of the stiffness of the foundation has been studied by adding springs at the supports.

  • 315.
    Axelsson, Kennet B. E.
    et al.
    Högskolan i Luleå, Luleå tekniska universitet, Luleå University of Technology.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Grennberg, Torsten
    Luleå tekniska universitet.
    Horrigmoe, Geir
    Luleå tekniska universitet.
    Johansson, Bernt
    Institutionen för Anläggningsteknik. Verksamhetsberättelse 1987/881988Rapport (Annet (populærvitenskap, debatt, mm))
  • 316.
    Axelsson, Kennet B. E.
    et al.
    Högskolan i Luleå, Luleå tekniska universitet, Luleå University of Technology.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Grennberg, Torsten
    Luleå tekniska universitet.
    Horrigmoe, Geir
    Luleå tekniska universitet.
    Johansson, Bernt
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Institutionen för Anläggningsteknik, Verksamhetsberättelse 1988/891989Rapport (Annet (populærvitenskap, debatt, mm))
  • 317.
    Axelsson, Kennet B. E.
    et al.
    Högskolan i Luleå, Luleå tekniska universitet, Luleå University of Technology.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Grennberg, Torsten
    Luleå tekniska universitet.
    Horrigmoe, Geir
    Luleå tekniska universitet.
    Johansson, Bernt
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Institutionen för Anläggningsteknik. Verksamhetsberättelse 1989/901990Rapport (Annet (populærvitenskap, debatt, mm))
  • 318.
    Axelsson, Kennet B. E.
    et al.
    Högskolan i Luleå, Luleå tekniska universitet, Luleå University of Technology.
    Johansson, Bernt
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Grennberg, Torsten
    Luleå tekniska universitet.
    Horrigmoe, Geir
    Luleå tekniska universitet.
    Institutionen för Anläggningsteknik. Verksamhetsberättelse 1990/911991Rapport (Annet (populærvitenskap, debatt, mm))
  • 319.
    Axelsson, Kenneth
    et al.
    Luleå tekniska universitet.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Bro1990Inngår i: Nationalencyclopedin, Höganäs: Bra Böcker , 1990, s. 320-324Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 320.
    Babiuc, Octavian
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Vägtekniks laboratorium.
    Effect of gritting sand quality on road dust pollution2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Pollution of air represents the contamination with matter that can affect both humanhealth and the environment. Road dust has been recognized as a dominant source ofparticulate matter and one of the factors that contributes to its development is the useof gritting sand. Gritting sand is being used during snowy winter conditions as atraction control method. During spring season, when snow and ice melt and surfacesdry out, and the influence of traffic, asphalt surface wear, particle ejection from tires,etc; under the effect of their interaction, cause the formation of particulate matter.A general aim of this study was to perform analysis of factors which can be consideredresponsible generating road pollution, with resistance to abrasion of gritting sandbeing a potential key problem. The correlation between the use of studded tires andparticulate matter formation has been considered to be one of major issues in urbanareas.In order to carry out this investigation, an individual study case was considered,measurements indicated that levels of pollution increased even after studded tires werebanned.The literature review revealed important knowledge gaps regarding the quantificationof particulate emissions from non-exhaust sources, most importantly, emissions due tolow quality gritting sanding. At this point, very little information is available thatcould be used for determining the resistance to abrasion of gritting sanding material.This is further supported by numerous institutions and companies, all suggesting thatquality of gritting sand is not taken into consideration. Gritting sand is part of abigger problem which also involves types of pavement, types of tires, weather,background pollution, etc. Furthermore, there is no practical method to characterizewear of resistance of gritting sand.

  • 321.
    Backman, Christer
    et al.
    Statens väg- och transportforskningsinstitut.
    Höbeda, Peet
    Statens väg- och transportforskningsinstitut.
    The performance of aggregates in a single surface dressing, subjected to wear by studded tyres1984Rapport (Annet vitenskapelig)
  • 322.
    Backström, Martin
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Byggnadsteknik.
    Wikström, Ludvig
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Byggnadsteknik.
    Effektivisering av ekologisk dagvattenhantering i stadsmiljö2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I Jönköping har problemet med översvämningar, erosion och materialtransport varit ett stort problem i Strömsbergsbäcken i Jönköpings kommun. Detta har tillviss del orsakats av ett ökat dagvattenutsläpp i bäcken, vilket skapar kraftigaflödestoppar då den ursprungliga fåran inte är ”dimensionerad” för den ökadevattenmängden. Syftet med arbetet är att effektivisera ekologisk dagvattenhantering i stadsmiljö med högt dagvattenutsläpp. Målet med arbetet är i sin tur att framställa underlag för hur ekologisk dagvattenhantering i stadsmiljö kan genomföras och att rapporten skall kunna ge värdefull kunskap till liknande sammanhang. För attuppfylla målet har följande tre frågeställningar utformats som utgör en väsentligdel av arbetet:

    • Hur kan belastningen på det allmänna dagvattennätet minskas?
    • Hur kan föroreningsföljderna av dagvattenavrinning i stadsmiljö minskas?
    • Vilka åtgärder är lämpliga för att effektivisera ekologisk dagvattenhantering i  Strömsbergsbäcken?

    Metoderna som använts för att besvara frågeställningarna är litteraturstudie, dokumentanalys och fallstudie. Resultaten visar på att vattenflödena från fyra av nio upptagningsområden som har sitt utlopp i Strömsbergsbäcken bör genomgå någon form av åtgärd som bromsar eller minskar dagvattenflödena innan det återgår till den naturliga vattencykeln. Dagvattenflödet kan minskas genom att anlägga åtgärder i området innan vattnet når vattendraget. Flödena kan också minskas genom åtgärder i anslutning tillbäcken, vid de utloppen där de största flödena förekommer. En väsentlig lösning för Strömsbergsbäcken är t.ex. att bygga om den befintliga branddammen, som ligger intill ett av utloppen, till en fördröjningsdamm för att bromsa en del av flödena i bäcken.

  • 323.
    Bagampadde, Umaru
    KTH, Tidigare Institutioner, Byggvetenskap.
    On investigation of stripping propensity of bituminous mixtures2004Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    In this study, an experimental programme was designed toestablish a relationship between bituminous mixture constituentmaterial properties and their propensity to moisture induceddamage in form of stripping. Six bitumen types (3 from Ugandaand 3 from Sweden) with presumably varying characteristics wereevaluated basing on rheology and chemistry. Eleven aggregateswere used in this study. Seven were sourced from activequarries in Uganda and four were from Sweden.

    Bitumen rheology was established basing on penetration,softening point, viscosity, ductility and visco-elasticparameters obtained from dynamic mechanical analysis. Bitumenchemistry was studied using Fourier Transform InfraredSpectroscopy, Gel Permeation Chromatography (GPC) and ThinLayer Chromatography (TLC).

    Bituminous mixtures were reconstituted from the bitumen andaggregate combinations basing on the Swedish mix designprocedure ROAD 94 using dense graded mixtures with 16mm maximumaggregate size (AG16). Mixture sensitivity to moisture wasevaluated basing on Swedish FAS 446-98 specifications closelyrelated to the modified Lottman procedure.

    The investigation was done in two phases namely, (a) theeffect of aggregate properties on mixture moisture sensitivityand (b) the of cross effects of bitumen and aggregates onmixture moisture sensitivity.

    The results reveal chemical compositional differences inbitumens that would be considered similar basing on classicalrheological properties like penetration and viscosity. Resultsof dynamic mechanical analysis show that binders have similarvisco-elastic response around 0oC. This could be a potentialphenomenon to serve as a grading scheme for bitumen as is thecase with penetration and viscosity grading systems.

    The results from phase I of the study show that presence ofCa-feldspars and ferromagnesian minerals in aggregates largelyrelates to improved resistance of mixtures to moisture damage.In addition, mixtures from aggregates with high concentrationsof acid insolubles (SiO2 and Al2O3) are sensitive to moisturedamage.

    The results of phase II of this study show that the choiceof aggregate type is the dominant factor affecting moisturesensitivity of the resulting mixtures. Bitumen type seems notto be an important factor in determining moisture sensitivityof bituminous mixtures. Aggregates with Ca-feldspars andferromagnesian minerals seemed to be the most resistant tomoisture damage irrespective of the bitumen type.

    Assessment of moisture sensitivity basing on absolutestiffness values of water treated mixtures seems not to bereliable. Results from this study show that mixtures withsimilar wet resilient moduli had varying tensile strengthratios, hence varying moisture sensitivity tendencies. Modulusof resilience ratio (MRR) and tensile strength ratio (TSR)parameters show similar trends in comparing moisturesensitivity of different mixtures. However, MRR values aregenerally lower than TSR values for the same mixtures.

  • 324.
    Bagampadde, Umaru
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Isacsson, Ulf
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Kiggundu, B
    Fundamentals of Stripping in Bituminous Pavements - State of the Art2003Rapport (Annet vitenskapelig)
  • 325.
    Bagampadde, Umaru
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Isacsson, Ulf
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Kiggundu, B
    Fundamentals of Stripping in Bituminous Pavements -State of the Art2003Rapport (Annet vitenskapelig)
  • 326.
    Bagampadde, Umaru
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Kiggundu, B
    Exploratory Stripping Investigations on Bituminous Mixtures in Uganda2002Konferansepaper (Fagfellevurdert)
  • 327.
    Bagdadi, Omar
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Patten, Christopher
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Dynamiska farthinder: en litteraturstudie2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    För att motverka de negativa konsekvenserna av solida farthinder, speciellt väggupp, har alternativa farthinder börjat komma, om än i begränsad omfattning. Ett alternativt farthinder kan vara utformat på olika sätt och vara antingen passivt dynamiskt eller aktivt dynamiskt. Passivt dynamiska farthinder är utformade så att tunga fordon kan passera nästan obemärkt med litet obehag medan vanliga bilister upplever liknande obehag som vid solida hinder och tvingas sänka hastigheten ordentligt. Aktivt dynamiska farthinder är däremot konstruerade så att det ska gå att hålla ett högt trafikflöde på en vägsträcka i jämn hastighet. Farthindret kräver inte att vare sig bilister eller tunga fordon saktar in under den tillåtna hastigheten för att passera obehindrat. De slutsatser som denna studie kan göra är att både passivt dynamiska och aktivt dynamiska farthinder är intressanta och kan till viss utsträckning ersätta och komplettera befintliga traditionella solida farthinder. Det är dock viktigt att påpeka att man bör vara tydlig med syftet och vilka effekter man vill åstadkomma i och med installationen av farthindret.

  • 328. Bagge, N.
    et al.
    Nilimaa, J.
    Blanksvärd, T.
    Täljsten, B.
    Elfgren, L.
    Sundquist, Håkan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Carolin, A.
    Assessment and failure test of a prestressed concrete bridge2017Inngår i: Life-Cycle of Engineering Systems: Emphasis on Sustainable Civil Infrastructure - 5th International Symposium on Life-Cycle Engineering, IALCCE 2016, CRC Press, 2017, s. 1058-1063Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Tests have been carried out at service- and ultimate load levels of a 55 year-old prestressed concrete girder bridge. The bridge, located in Kiruna, Sweden, was continuous in five spans with a total length of 121.5 m. The overall aim of the study was to determinate the accuracy of assessment methods for existing structures and to provide procedures for optimized assessment. Before the tests a 2D finite element (FE) analysis was performed to predict the behavior and load-carrying capacity of the bridge. In order to more accurately assess the bridge response a 3D FE model has now been developed. The actual loading history and material properties has been considered in the model. A Life Cycle Cost Assessment of the bridge has also been performed.

  • 329.
    Bagge, Niklas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Assessment of Concrete Bridges: Models and Tests for Refined Capacity Estimates2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Optimising the strategy for repairing, upgrading and replacing bridges in the European Union, and elsewhere, is becoming increasingly important due to ageing of the bridge stock, continuously increasing load requirements and budgetary limitations. Thus, there is a clear need to identify or develop, and implement, refined methods for assessing existing bridges in order to determine the most cost-effective options and actions to extend their lives, increase their capacities or replace them.Thus, the objective of the research project partly reported in this licentiate thesis is to verify and calibrate methods for refined assessment of existing bridges, using information acquired in an extensive program of experimental studies. In addition to describing parts of the project, the thesis is intended to provide a basis for suggestions and a discussion of the author’s future research in the area. It includes presentations of two experimental studies designed to evaluate, and calibrate, assessment methods:1. A laboratory-based experimental study of 12 two-span continuous reinforced concrete beams conducted in Dublin, Ireland, in 2012. The tests particularly focused on the beams’ nonlinear overall behaviour and related redistribution of internal forces.2. A full-scale test of a 55 year-old post-tensioned girder bridge in Kiruna, Sweden, in 2014, focusing on: (a) failure loading of the main girders, (b) failure loading of the slab, (c) the condition of post-tension cables, and (d) two strengthening systems using carbon fibre reinforced polymers (CFRP).The continuous reinforced concrete beams behaved in a nonlinear manner from an early stage in the loading. This is not usually considered in either the design or assessment of existing bridges, but should be for the verification to be accurate at the serviceability and ultimate limit states (SLS and ULS, respectively). The results also indicated that there was more redistribution of internal forces at the ULS than stated in standards. Thus, use of refined methods to assess bridges or other reinforced concrete structures can be beneficial for avoiding unnecessary repairs, strengthening or replacement measures. In addition, the tests demonstrated the importance of taking into account the interaction between flexural moments and shear forces. This is not considered in shear force resistance models included in, for example, the European standard.To date, too few reinforced concrete bridges have been tested to failure to parameterise assessment models robustly with low uncertainty levels. Thus, a programme aimed for verification and calibration of models for assessing existing bridges was designed. The comprehensive programme is described in the thesis, which also provides suggestions and a discussion for future research based on the tests and associated monitoring.During the full-scale tests of the Kiruna Bridge, data were acquired that are relevant to investigations in several fields related to bridge assessment. For instance the obtained data provide foundations for future research concerning: (a) the robustness, ductility and bridge behaviour, (b) the shear force and punching resistance of bridge girders and slabs, (c) assessment of post-tensioned steel cables’ condition, (d) strengthening methods using CFRP, (e) updating finite element models, and (f) reliability-based analysis.

  • 330.
    Bagge, Niklas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Structural assessment procedures for existing concrete bridges: Experiences from failure tests of the Kiruna Bridge2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Assessing existing bridges is an important task in the sustainable management ofinfrastructure. In practice, structural bridge assessments are usually conducted usingtraditional and standardised methods, despite knowledge that these methods oftenprovide conservative estimates. In addition, more advanced methods are available, suchas nonlinear finite element (FE) analysis, that are used for research purposes and cansimulate the structural behaviour of bridges more accurately. Therefore, it would beuseful to develop practical and reliable procedures for refined assessments using theseadvanced techniques.Focusing on the ultimate load-carrying capacity of existing concrete bridges, this thesispresents a procedure for structural assessments. The fundamental idea is to improve theassessment successively, as necessary to predict bridges’ structural behaviour adequately.The procedure involves a multi-level assessment strategy with four levels of structuralanalysis, and an integrated framework for safety verification. At the initial level (Level 1)of the multi-level strategy, traditional standardised methods are used, no failures arecovered implicitly in the structural analysis and action effects are verified using localresistances calculated using analytical models. In the subsequent enhanced levels (Levels2 – 4), nonlinear FE analysis is used for stepwise integration of the verification of flexural,shear-related and anchorage failures into the structural analysis. The framework for safetyverifications includes partial safety factor (PSF), global resistance safety factor (GRSF) andfull probabilistic methods. Within each of these groups, verifications of desired safetymargins can be conducted with varying degrees of complexity.To demonstrate and evaluate the proposed structural assessment procedure, comparativestudies have been carried out, based on full-scale tests of a prestressed concrete bridge.This was the Kiruna Bridge, located in the northernmost city in Sweden, which was duefor demolition as part of a city transformation project, necessitated by large grounddeformations caused by the large nearby mine. Thus, it was available for destructiveexperimental investigation within the doctoral project presented in this thesis. The bridgehad five continuous spans, was 121.5 m long and consisted of three parallel girders with a connecting slab at the top. Both the girders and slab were tested to failure to investigatetheir structural behaviour and load-carrying capacity. Non-destructive and destructivetests were also applied to determine the residual prestress forces in the bridge girders andinvestigate the in situ applicability of methods developed for this purpose. The so-calledsaw-cut method and decompression-load method were used after refinement to enabletheir application to structures of such complexity. The variation of the experimentallydetermined residual prestress forces was remarkably high, depending on the sectioninvestigated. There were also high degrees of uncertainty in estimated values, and thusare only regarded as indications of the residual prestress force.Level 1 analysis of the multi-level assessment strategy consistently underestimatedcapacity, relative to the test results, and did not provide accurate predictions of the shearrelatedfailure observed in the test. With linear FE analysis and local resistance modelsdefined by the European standard, Eurocode 2, the load-carrying capacity wasunderestimated by 32 % for the bridge girder and 55 % for the bridge deck slab. At theenhanced level of structural analysis (Level 3), nonlinear FE analyses predicted thecapacities with less than 2 % deviation from the test results and correctly predicted thefailure mode. However, for existing bridges there are many uncertainties, for instance,the FE simulations were sensitive to the level of residual prestressing, boundaryconditions and assumed material parameters. To accurately take these aspects intoaccount, bridge-specific information is crucial.The complete structural assessment procedure, combining the multi-level strategy andsafety verification framework, was evaluated in a case study. Experiences from theprevious comparative studies were used in an assessment of the Kiruna Bridge followingthe Swedish assessment code. The initial assessment at Level 1 of the multi-level strategyand safety verification, using the PSF method, indicated that the shear capacity of one ofthe girders was critical. The most adverse load case (a combination of permanent loads,prestressing and variable traffic loads) was further investigated through enhancedstructural analyses implicitly accounting for flexural and shear-related failures (Level 3).Nonlinear FE analysis and safety evaluation using the PSF method, several variants of theGRSF method and the full probabilistic analysis for resistance indicated that the permittedaxle load for the critical classification vehicle could be 5.6 – 6.5 times higher than thelimit obtained from the initial assessment at Level 1. However, the study also indicatedthat the model uncertainty was not fully considered in these values. The modeluncertainty was shown to have strong effects on the safety verification and (thus)permissible axle loads. The case study also highlighted the need for a strategy forsuccessively improving structural analysis to improve understanding of bridges’ structuralbehaviour. The refined analysis indicated a complex failure mode, with yielding of thestirrups in the bridge girders and transverse flexural reinforcement in the bridge deck slab,but with a final shear failure of the slab. It would be impossible to capture suchcomplexity in a traditional standardised assessment, which (as mentioned) indicated thatthe shear capacity of the girder limited permissible axle loads. However, nonlinear FEanalyses are computationally demanding, and numerous modelling choices are required.Besides a strategy for rationally improving the analysis and helping analysts to focus oncritical aspects, detailed guidelines for nonlinear FE analysis should be applied to reduce the analyst-dependent variability of results and (thus) the model uncertainty. Clearly, toensure the validity of bridge assessment methods under in situ conditions, theirevaluations should include in situ tests. This thesis presents outcomes of such tests, therebyhighlighting important aspects for future improvements in the assessment of existingbridges.

  • 331.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Bernspång, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Carolin, Anders
    Trafikverket.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Full-Scale Test to Failure of a Prestressed Concrete Bridge in Kiruna2014Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 50, s. 83-86Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To calibrate methods for condition assessment of prestressed concrete (PC) bridges, tests are planned for a 50 year old five-span bridge with a length of 121 m in Kiruna in northern Sweden. Both non-destructive and destructive full-scale tests will be performed. This paper summarises the test programme, which comprises evaluation of the structural behaviour of the bridge, the residual forces in the prestressed steel, methods for strengthening using carbon fibre reinforced polymers (CFRP) and the shear resistance of the bridge slab.

  • 332.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Structural performance and failure loading of a 55 year-old prestressed concrete bridge2016Inngår i: Maintenance, Moniring, Safety, Risk and Resilience of Bridges and Bridge Networks / [ed] Tulio N. Bittencourt; Dan M. Frangopol; André T. Beck, London: CRC Press, Taylor & Francis Group, , 2016, s. 2225-2232Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Tests have been performed at service- and ultimate load levels of a 55 year-old 121.5 m long prestressed concrete bridge. The purpose was to acquire data for enhanced assessment and calibration of such methods. At service-load several truck overpasses and the dynamic response were particularly studied. Some conclusions were: (a) less stiff load-deflection behavior was obtained with a finite element (FE) analysis compared to measurements and (b) good agreement was obtained for predicted and tested dynamic characteristics. The focus in the destructive tests was on the overall bridge behavior and the ultimate load-carrying capacity of the bridge’s girders and slab. The results were: (a) combined flexure-shear failure of girders occurred after reinforcement yielding for a load indicating an appreciable safety margin in relation to code predictions and (b) good agreement was obtained between FE analysis and the ultimate response and capacity of the tested bridge

  • 333.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Bernspång, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion. Norut Northern Research Institute, Narvik.
    Tu, Yongming
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion. College of Civil Engineering, Southeast University, Nanjing.
    Carolin, Anders
    Trafikverket, Trafikverket, Luleå.
    Performance of a prestressed concrete bridge loaded to failure2015Inngår i: IABSE Conference Geneva 2015: Structural Engineering: Providing Solutions to Global Challenges, Geneva: International Association for Bridge and Structural Engineering, 2015, s. 1088-1095Konferansepaper (Annet vitenskapelig)
  • 334.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Instrumentation and Full-Scale Test of a Post-Tensioned Concrete Bridge2014Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 51, s. 63-83Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To meet new demands, existing bridges might be in need for repair, upgrading or replacement. To assist such efforts a 55-year-old post-tensioned concrete bridge has been comprehensively tested to calibrate methods for assessing bridges more robustly. The programme included strengthening, with two systems based on carbon fibre reinforced polymers (CFRPs), failure loading of the bridge’s girders and slab, and determination of post-tension cables’ condition and the material behaviour. The complete test programme and related instrumentation are summarised, and some general results are presented. The measurements address several current uncertainties, thereby providing foundations for both assessing existing bridges’ condition more accurately and future research.

  • 335.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sundquist, Håkan
    Royal Institute of Technology.
    Carolin, Anders
    Trafikverket, Luleå.
    Assessment and failure test of a prestressed concrete bridge2017Inngår i: Life-Cycle of Engineering Systems: Emphasis on Sustainable Civil Infrastructure / [ed] Jaap Bakker; Dan M Frangopol; Klaas van Breugel, Leiden: CRC Press/Balkema , 2017, s. 1058-1063Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Tests have been carried out at service- and ultimate load levels of a 55 year-old prestressed concrete girder bridge. The bridge, located in Kiruna, Sweden, was continuous in five spans with a total length of 121.5 m. The overall aim of the study was to determinate the accuracy of assessment methods for existing structures and to provide procedures for optimized assessment. Before the tests a 2D finite element (FE) analysis was performed to predict the behavior and load-carrying capacity of the bridge. In order to more accurately assess the bridge response a 3D FE model has now been developed. The actual loading history and material properties has been considered in the model. A Life Cycle Cost Assessment of the bridge has also been performed

  • 336.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Evaluation of residual prestress force in a concrete girder bridge2016Inngår i: IABSE CONGRESS, STOCKHOLM, 2016: Challenges in Design and Construction of an Innovativeand Sustainable Built Environment / [ed] Lennart Elfgren, Johan Jonsson, Mats Karlsson, Lahja Rydberg-Forssbeck and Britt Sigfrid, CH - 8093 Zürich, Switzerland, 2016, s. 222-229Konferansepaper (Fagfellevurdert)
    Abstract [en]

    When assessing the structural behaviour of prestressed concrete bridges, understanding the level of prestressing is crucial. However, for existing structures, this is usually an unknown parameter and the literature only describes a few methods of experimentally determining the residual prestress forces. For this paper, a non-destructive testing approach has been evaluated based on testing of a multi-span continuous girder bridge. The method, consisting of in-situ measurements in combination with finite element (FE) simulations, revealed prestress levels in the range 25 % to 82 % of the reinforcement steel yield strength, depending on the section tested. A comparison with theoretically calculated residual prestress forces, taking into account friction and timedependent losses, indicated values of the same order but with some inconsistencies.

  • 337.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Nilimaa, jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    In-situ methods to determine residual prestress forces in concrete bridges2017Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 135, s. 41-52Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Levels of residual prestress forces are key parameters when assessing the structural behaviour of existing prestressed concrete bridges. However, these parameters are often unknown and not easy to determine. To explore them, two existing non-destructive and destructive approaches have been further developed for practical application and demonstrated on a multi-span continuous girder bridge. The evaluation of the prestress forces was part of an extensive experimental programme aimed to calibrate and develop assessment methods. Due to the pursuit of practical applications for existing bridges, the main focus was on non-destructive methodology, combining experimental data and finite element modelling to obtain the residual prestress forces. Assuming that the initial prestress force corresponded to 85% of the characteristic 0.2% proof strength of the reinforcing steel, estimated losses in investigated sections ranged between 5 and 70%. However, determined residual prestress forces were generally higher than theoretically based estimates accounting for friction and time-dependent losses in the prestressing system. In addition to describing in detail the methods for prestress evaluation, this paper presents suggestions for improvements and further studies, based on experiences from the field tests.

  • 338.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Enochsson, Ola
    Sabourova, Natalia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Grip, Niklas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lundmark, Tore
    Ramböll Sverige AB, Luleå.
    Tu, Yongming
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Protecting a five span prestressed bridge against ground deformations2015Inngår i: IABSE Conference Geneva 2015: Structural Engineering: Providing Solutions to Global Challenges, Geneva: International Association for Bridge and Structural Engineering, 2015, s. 255-262Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    A 55 year-old, 121.5 m long, five span prestressed bridge was situated in the deformation zone close to a mine in Kiruna in northern Sweden. There was a risk for uneven ground deformations so the bridge was analyzed and monitored. Results and measures taken to ascertain the robustness of the bridge are presented.The analysis resulted in an estimate that the bridge could sustain 24 mm in uneven horizontal and 83 mm in uneven vertical displacement of the two supports of a span. To be able to sustain larger deformations, the columns of the bridge were provided with joints, where shims could be inserted to counteract the settlements. To accomplish this, each one of the 18 columns of the bridge was unloaded by help of provisional steel supports. The column was then cut and a new foot was mounted to it. This made it possible to lift each individual column with two jacks, when needed, and to adjust its height by inserting or taking away shim plates.The deformations of the bridge and the surrounding ground were monitored. The eigenmodes of the bridge were studied with accelerometers and by analysis with finite elements (FE) models. Comparison indicated good agreement between the model and the actual bridge, with calculated eigenfrequencies of 2.17, 4.15 and 4.67 Hz, for the first transversal, vertical and torsional modes, respectively. Measurements during winter resulted in higher values due to increased stiffness caused by frozen materials.

  • 339.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Puurula, Arto
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Carolin, Anders
    Trafikverket, Luleå.
    Full-Scale Tests to Failure Compared to Assessments: Three Concrete Bridges2017Inngår i: High Tech Concrete: Where Technology and Engineering Meet - Proceedings of the 2017 fib Symposium / [ed] Lukovic M.,Hordijk D.A., Cham: Springer, 2017, s. 1917-1924Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Three Swedish concrete bridges have been tested to failure and the results have been compared to assessment using standard code models and advanced numerical methods.

    The three tested and assessed bridges were:

    1. (1)

      Lautajokk, a 29 year old one span (7 m) concrete trough bridge tested in fatigue to check the concrete shear capacity.

       
    2. (2)

      Ӧrnskldsvik, a 50 year old two span trough bridge (12 + 12 m) strengthened to avoid a bending failure.

       
    3. (3)

      Kiruna Mine Bridge, a 55 year old five span prestressed concrete road bridge (18 + 21 + 23 + 24 + 20 m) tested in shear and bending of the beams and punching of the slab.

       

    The main results in the paper are the experiences of the real failure types, the robustness/weakness of the bridges, and the accuracy of different codes and models. In all three cases the bridges had a considerable hidden capacity.

  • 340.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. WSP, Luleå, Sweden.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Norut Teknik, Norut, Norge.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Bernspång, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Carolin, Anders
    Trafikverket, Luleå.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Assessment of concrete bridges - Structural capacity: Experiences from full-scale testing to failure of a bridge in Kiruna2017Inngår i: Proceedings of the 23rd Nordic Concrete Research Symposium, Oslo, Norway: Nordic Concrete Federation, Oslo: Nordic Concrete Federation , 2017, s. 263-266Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To calibrate methods for condition assessment of prestressed concrete (PC) bridges, tests were carried out on a 55 year old five-span bridge with a length of 121 m in Kiruna in northern Sweden. Both non-destructive and destructive full-scale tests were performed. This paper presents results regarding methods for assessment of the structural capacity of concrete bridges.

  • 341.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Tu, Yongming
    College of Civil Engineering, Southeast University, Nanjing.
    Carolin, Anders
    Trafikverket.
    Loading to failure of a 55 year old prestressed concrete bridge2015Inngår i: IABSE Workshop Helsinki 2015: Safety, Robustness and Condition Assessments of Structures, Zurich: International Association for Bridge and Structural Engineering, 2015, s. 130-137Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to provide relevant data for calibration and development of methods for assessment ofexisting bridges, a 55 year old posttensioned concrete bridge has been subjected to non-destructiveand destructive tests. The bridge, located in Kiruna, Sweden, was a 121 m long girder bridgecontinuous in five spans. The test programme included failure loading of the girders and slab,respectively, condition assessment of the post-tensioned cables and material tests. Moreover, twostrengthening systems, using carbon fibre reinforcing polymer (CFRP), were evaluated. In this paperthe experimental programme and some preliminary results are presented to give an insight to researchproject.

  • 342.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. WSP, Luleå, Sweden.
    Nilimaa, Jonny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Norut Teknik, Norut, Norge.
    Blanksvärd, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Täljsten, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Carolin, Anders
    Trafikverket, Luleå.
    Paulsson, Björn
    Trafikverket; UIC, Paris, France; Charmec, Chalmers tekn högskola.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Assessment of concrete bridges - Prestress forces: Experiences from full-scale testing to failure of a bridge in Kiruna2017Inngår i: Proceedings of the 23rd Nordic Concrete Research Symposium, Oslo, Norway: Nordic Concrete Federation, Oslo: Nordic Concrete Federation , 2017, s. 267-270Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To calibrate methods for condition assessment of prestressed concrete (PC) bridges, tests were carried out on a 55 year old five-span bridge with a length of 121 m in Kiruna in northern Sweden. Both non-destructive and destructive full-scale tests were performed. This paper presents results regarding the residual forces in the prestressed reinforcement.

  • 343.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    O'Connor, Alan
    Department of Civil, Structural and Environmental Engineering, Trinity College Dublin.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pedersen, Claus
    Department of Bridges, Rambøll Danmark A/S.
    Moment redistribution in RC beams: A study of the influence of longitudinal and transverse reinforcement ratios and concrete strength2014Inngår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 80, s. 11-23Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, the results from an experimental programme, aimed at investigating moment redistribution in statically indeterminate reinforced concrete structures, are presented and compared with theoretical analysis of the structural behaviour. Due to the nonlinear structural behaviour of reinforced concrete structures, linear elastic analysis can lead to an inaccurate assessment of the behaviour and, therefore, it can become necessary to use more advanced methodologies to achieve sufficiently accurate analysis. Furthermore, more advanced methods can enable a higher degree of performance optimisation of structures than those resulting from the simplified approaches adopted by existing design codes based on linear elastic analysis with redistribution of internal forces. In order to assess the load-carrying capacity at the ultimate limit state (ULS), a model combining plastic and nonlinear analysis is presented. The evolution of moment redistribution to structural collapse was studied experimentally for continuous two-span beams. The focus of the experiments was on the influence of the longitudinal tensile reinforcement ratio at the intermediate support, the transverse reinforcement ratio and the concrete strength. The experimental response at the ULS was further compared with the predicted distribution of internal forces according to the theoretical model. Evaluation of the experimental study indicated a highly nonlinear structural behaviour of the tested beams with the distribution of moment differing from linear elastic analysis, even for low load levels. The evolution of moment redistribution and the moment redistribution at the ULS were appreciably dependent on the arrangement of longitudinal reinforcement, whilst the transverse reinforcement ratio had a marginal impact up to yielding of the longitudinal reinforcing steel, with the concrete strength slightly reducing the degree of moment redistribution. For those beams which failed in flexure, predictions from the theoretical model presented were in good agreement with the experimental results. However, several beams collapsed in shear-related failure modes.

  • 344.
    Bagge, Niklas
    et al.
    Department of Bridges, Rambøll Danmark A/S, Department of Civil, Structural and Environmental Engineering, Trinity College Dublin.
    O'Connor, Alan
    Department of Civil, Structural and Environmental Engineering, Trinity College Dublin.
    Pedersen, Claus
    Department of Bridges, Rambøll Danmark A/S.
    Rotation capacity and plastic redistribution of forces in reinforced concrete beams2012Inngår i: Proceedings of Bridge and Concrete Research in Ireland Conference / [ed] Colin Caprani; Alan O'Connor, Dublin: Bridge and Concrete Research in Ireland , 2012, s. 517-522Konferansepaper (Fagfellevurdert)
  • 345.
    Bagge, Niklas
    et al.
    Department of Bridges, Rambøll Danmark A/S, Department of Civil, Structural and Environmental Engineering, Trinity College Dublin.
    Pedersen, Claus
    Department of Bridges, Rambøll Danmark A/S.
    O'Connor, Alan J.
    Department of Civil, Structural and Environmental Engineering, Trinity College Dublin.
    Prediction of moment redistribution and influence of rotation capacity in reinforced concrete beams2012Inngår i: Bridge Maintenance, Safety, Management, Resilience and Sustainability / [ed] Fabio Biondini; Dan M. Frangopol, London: CRC Press, Taylor & Francis Group , 2012, s. 292-292Konferansepaper (Fagfellevurdert)
  • 346.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Bridge & Hydraulic Design, WSP Sverige AB, Gothenburg, Sweden.
    Plos, M.
    Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden.
    Popescu, Cosmin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Norut Northern Research Institute, Narvik, Norway.
    A multi-level strategy for successively improved structural analysis of existing concrete bridges: examination using a prestressed concrete bridge tested to failure2019Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 15, nr 1, s. 27-53Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper describes a multi-level strategy with increased complexity through four levels of structural analysis of concrete bridges. The concept was developed to provide a procedure that supports enhanced assessments with better understanding of the structure and more precise predictions of the load-carrying capacity. In order to demonstrate and examine the multi-level strategy, a continuous multi-span prestressed concrete girder bridge, tested until shear failure, was investigated. Calculations of the load-carrying capacity at the initial level of the multi-level strategy consistently resulted in underestimated capacities, with the predicted load ranging from 25% to 78% of the tested failure load, depending on the local resistance model applied. The initial assessment was also associated with issues of localising the shear failure accurately and, consequently, refined structural analysis at an enhanced level was recommended. Enhanced assessment using nonlinear finite element (FE) analysis precisely reproduced the behaviour observed in the experimental test, capturing the actual failure mechanism and the load-carrying capacity with less than 4% deviation to the test. Thus, the enhanced level of assessment, using the proposed multi-level strategy, can be considered to be accurate, but the study also shows the importance of using guidelines for nonlinear FE analysis and bridge-specific information. 

  • 347.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Popescu, Cosmin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Failure tests on concrete bridges: Have we learnt the lessons?2018Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 14, nr 3, s. 292-319Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Full-scale failure tests of bridges are important for improving understanding of bridges’ behaviour and refining assessment methods. However, such experiments are challenging, often expensive, and thus rare. This paper provides a review of failure tests on concrete bridges, focusing on lessons from them. In total, 40 tests to failure of 30 bridges have been identified. These include various types of bridges, with reinforced concrete or prestressed concrete superstructures, composed of slabs, girders and combinations thereof. Generally, the tests indicated that theoretical calculations of the load-carrying capacity based on methods traditionally used for design and assessment provide conservative estimates. It can also be concluded that almost a third of the experiments resulted in unexpected types of failures, mainly shear instead of flexure. In addition, differences between theoretical and tested capacities are often apparently due to inaccurate representation of geometry, boundary conditions and materials

  • 348.
    Bagge, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Shu, Jiangpeng
    Chalmers University of Technology.
    Plos, Mario
    Chalmers University of Technology.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Punching Capacity of a Reinforced Concrete Bridge Deck Slab Loaded to Failure2015Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Full-scale failure tests of a 55 year old prestressed concrete girder bridge have been carried out to calibrate models for assessment of existing bridges. This paper summarises the outcome from the punching test and analytical analysis according to the model stated in the Eurocode. The experimental load was approximately 2.4 times the code value using measured material properties.

  • 349.
    Bailly, Cyril
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Wind turbine dynamic - application to foundations2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    These latest years, the green energy is highlighted and new technologies appeared. It is the case for wind turbines. The aim of latest developments has been to increase the power output. The use of new material enables the design of wind turbine with an impressive height, more and more flexible, inducing significant dynamic forces.

    However, several problems have been encountered on the connection between the foundation and the tower, which threaten the entire integrity of the structure. The initial lifetime could be impacted.

    The first aims of the master thesis are to understand the dynamic behavior of a wind turbine, determine the resultant forces at the foundation in order to explain the issues encountered at the foundation level on site, and compare these results with the resultant forces given by the wind turbine manufacturer.

    Indeed, the constructor transmits to the civil engineer one or more resultants forces without justifications in order to design the foundation. These loads are often issued from extreme load case. The analysis of the serviceability limit state is not well realized. It is this resultant force in operation which must be determined in this master thesis.

    After having presented the history of wind turbines, the different parts and the model use for the wind; the blade element model is used to calculate the forces of the wind on the rotor. These forces calculated from the theory used are eventually compared with the provider data.

    The turbulence component of the wind on the tower is evaluated by a spectral method and a fluid structure interaction with the software Abaqus. The inertial effects of the tower are calculated in order to give an order of magnitude of the resultant load on the foundations.

    This knowledge enables to analyze the connection in serviceability limit state which is another aim of the study. An analysis of the connection is done in order to get an idea of the risks. In particular, the punching resistance and the stability of the structure are verified.

  • 350.
    Bak, Monika
    et al.
    University of Gdansk.
    Borkowski, Przemyslaw
    University of Gdansk.
    Burnewicz, Jan
    University of Gdansk.
    Pawlowska, Barbara
    University of Gdansk.
    Enei, Ricardo
    ISIS.
    To be a new member state: What does it mean for pricing policy2008Rapport (Annet vitenskapelig)
    Abstract [en]

    This deliverable is dedicated to the area of the third work package of CATRIN covering new member states’ policy and implementation problems as well as data availability. The objective of already submitted Deliverable 5 was to review data sources and information available in new member states which can be used for cost allocation studies. This deliverable addresses the CATRIN Task 3.1 “Review of important issues in transport policy”, in which the main objective is to provide an indication on the general assumptions, preconditions and key factors for ensuring a fair and efficient pricing policy at country level.The insights from the EC transport policy prove that some characteristics as basic preconditions for the implementation of fair pricing reforms in transport can be identified. Those include:

    • The non-discrimination principle aiming at providing a charging system that does not discriminate between operators and/or Member States.

    • The transparency principle (cost allocation), implying that the required charges (to the user) should be determined in a transparent way. This has also implied, in presence of natural monopoly, the danger of anticompetitive collusion and/or the concentration of market power in particular operators, the establishment of independent authorities able to guarantee the third party right (new entrants) to a fair charging, e.g. in the case of air and rail sector.

    • Consultation as a general method of defining and implementing charging involving stakeholders.

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