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  • 1.
    Alm, Ove
    et al.
    Luleå tekniska universitet.
    Norin, Jonas
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Experimentella bestämningar av mekaniska egenskaper för hårdmetallpulver: slutrapport över pilotstudie1982Report (Other academic)
  • 2.
    Alm, Ove
    et al.
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Attempt to make accurate measurements of deformations of compressible soilds at high pressure and different states of stress1982In: High pressure in research and industry: 8th AIRAPT Conference, 19th EHPRG Conference, 17 - 22 August 1981, Institte of Physical Chemistry, University of Uppsala, Sweden ; proceedings / [ed] C.-M. Backman, Uppsala: Fysikalisk-kemiska inst., Univ , 1982, p. 619-622Conference paper (Refereed)
  • 3.
    Babic, N.C.
    et al.
    University of Maribor.
    Rebolj, D.
    University of Maribor.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Schumacher, S.
    P3 Ingenieurgesellschaft.
    InPro training environment and model based working in construction2009In: Improving Construction and Use through Integrated Design Solutions: First International Conference on CIB IDS 2009 / [ed] Kaisa Belloni; Jun Kojima; Isabel Pinto Seppä, Espoo: Valtion teknillinen tutkimuskeskus. Tie- ja liikennelaboratorio , 2009, p. 72-86Conference paper (Refereed)
    Abstract [en]

    InPro project is European initiative which is developing a model based and collaborative way of working in early design phase in construction. To support project goals and facilitate the industrial transformation and industrial technology take-up, the project implemented tools and developed curricula and materials for training and education of management, architects, engineers, and construction workers, as well as university students. The paper presents training environment architecture with BIM laboratory that was developed to support training on model based work practices and enhancement of hands-on skills. Development process, technical solutions and experiences are described. Content of training courses and curricula is based on experiences from live project demonstrations and use cases. The paper presents one of the answers that address the problem of insufficient skills in construction industry that prevent adoption of novel methods of working and technology.

  • 4. Bennitz, Anders
    et al.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Kronborg, A.
    Wahlberg, A.
    Dynamic behaviour of the Vindel River railway bridge2006In: Condition Monitoring and Diagnostic Engineering Management: COMADEM 2006: proceedings / [ed] Uday Kumar; Aditya Parida; Raj B. K. N. Rao, Luleå: Luleå tekniska universitet, 2006, p. 721-729Conference paper (Refereed)
    Abstract [en]

    The Swedish Railway administration has launched several projects aimed at increasing the accessibility of the railway lines in northern Sweden to meet future demands. One of these lines connects the southern and northern parts of Sweden and constitutes one of the major arteries for the transportation of heavy goods. Major investment are planned to upgrade the load bearing capacity of this railway line. The work is mainly focused on the larger structures and their dynamical properties. These properties can be used to assess existing infrastructure and to evaluate the performance. Advantages are obvious since the existing structural integrity form the base for investments in structural repair and upgrade of bridges. The Vindel River Railway Bridge situated 55 kilometers northwest of Umeå came into focus when large motion was discovered during train passages. The behaviour of the bridge crossing the river of Vindeln has been measured two times. Measurements of displacements and acceleration of the bridge during train passages has been conducted, the first measurements was done to give more experience on the motion of the bridge and to try out new sensors. The second measurement gave more information about the bridge's motion, results that could be used to calibrate a 3D FE-Model of the bridge used in the study. Based on the measurements, eigenfrequencies in the range of 0 to 8 Hz could be detected, modal shapes up to the ninth order could be extracted, deflections and transverse displacements for different sets of train and different train speeds were also found. However, new measurements are planned for this summer and will hopefully reinforce the already attained result and give answers to some of the unresolved questions.

  • 5.
    Blokpoel, Sjoerd
    et al.
    Luleå tekniska universitet.
    Jongeling, Rogier
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Cooperation and product modelling systems2004In: Proceedings of the 5th European Conference of Product and Process Modelling in the Building and Construction Industry / [ed] Attila Dikbas; Raimar Scherer, Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 2004, p. 423-430Conference paper (Refereed)
    Abstract [en]

    This paper deals with the introduction of product modelling in today's building process. The main potentials of these systems are facilitating open communication, configuration management, reuse of information, virtual prototyping in 4D and allowing numerous analyses on e.g. life cycle, energy use and accurate estimates of project costs. The modelling systems have prerequisites for application that are not fulfilled by the construction industry. Therefore, the potential benefits cannot be derived at the moment. Most unfulfilled prerequisites are related to the way of cooperation. New building process organisation types, like partnering, offer a better way to approach a project and a good basis to use the systems. The development of these organisation types should be integrated in the application of models because the systems could be a good tool, and maybe even an enabler. Legal issues are no roadblock for application, but need attention. The current contracts are sufficient, but need an add-on for procedures in the use of ICT. A third party should keep an encrypted logfile to ensure tracebility of changes. Model errors in exchange files can occur and cause problems. Producers of data should be responsible for the produced data and check its consistency. Middleware is needed to exchange only core model information and to allow company based ICT systems that connect through a shared modelling system. The main strength of the application is configuration management and a database with information to improve communication. The main weakness is the lack of clear, measurable benefits and costs Key Performance Indexes (KPI's). The main opportunities are current developments in partnering, which make the application of systems better possible. Main threats are the fragmentised view in the sector, both in phases, in a project and of projects by a company and the lack of good cooperation.

  • 6.
    Bröchner, Jan
    et al.
    Organization of Construction, Department of Technology Management and Economics, Chalmers University of Technology.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Construction productivity measures for innovation projects: case study2012In: Journal of construction engineering and management, ISSN 0733-9364, E-ISSN 1943-7862, Vol. 38, no 5, p. 670-677Article in journal (Refereed)
    Abstract [en]

    A 30‐year retrospective analysis of resource use in a range of new construction and repair projects reveals insignificant productivity increase when applying traditional narrow measures, as shown in a case study of beam bridges. It appears as necessary to estimate hidden quality changes in both outputs and inputs. Changes in government regulations, in specifications and the development of non‐price criteria for contract award emerge as important. Schemes for benchmarking the performance of construction projects as well as life‐cycle analyses suggest that customer risk aversion and effects on customer productivity should be taken into account. The outcome is a set of measurements which can be applied to the selection of any type of proposed new construction or repair technology innovation according to their potential impact on industry productivity

  • 7. Carlswärd, Jonas
    et al.
    Emborg, Mats
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Shrinkage cracking of steel fiber reinforced self compacting concrete overlays: test methods and theoretical modelling2007In: Proceedings of the 5th International Rilem Symposium on Self-Compcting Concrete: SCC2007 / [ed] G. De Schutter ; G. De Schutter . Boel, Bagneux, France: Magnel Laboratory for Concrete Research, Ghent University , 2007, p. 793-798Conference paper (Refereed)
  • 8.
    Dehlin, S.
    et al.
    NCC Construction Sverige AB.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Racz, Tamas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Heikkilä, K.
    Colvo Group Real Estate.
    Practical application of a newly developed automated building energy-analysis software module prototype2012In: eWork and eBusiness in Architecture, Engineering and Construction: Proceedings of the European Conference on Product and Process Modelling 2012 , ECPPM 2012 / [ed] Gudni Gudnason; R J Scherer, Boca Raton: CRC Press, Taylor & Francis Group , 2012, p. 45-49Conference paper (Refereed)
    Abstract [en]

    One key challenge when it comes to developing industrial building concepts for the housing industry is improving the energy performance of buildings, while at the same time ensuring that the end product remains affordable and attractive to customers. This paper summarises the findings from the application of a newly developed prototype for an automated energy-analysis software module in a real-life project.The prototype is used for the energy analysis of the low-energy, multi-family residential P303 concept developed by NCC Construction Sverige AB - a leading construction and development company in the Nordic region. A building concept is based on continuity and repetitions of most of the building components. Most of its characteristics are known and defined beforehand and only a few parameters vary due to the adaptation of the concept, for example, the configuration or site location. In energy performance calculations, the proposed energy-analysis software module prototype processes the known parameters as constants and only varies the unknown parameters. The energy calculations are then carried out by the calculation kernel from the dynamic building simulation software module, VIP Energy, and the result is exported to an Excel spreadsheet where it is presented in a table. This makes it possible, in a practical manner, to execute a larger number of performance analyses in a shorter time, investigating different design alternatives and configurations and thereby facilitating optimisation towards the best possible design solution. The case study presented in this paper simulated energy losses through the building envelope of a real P303 building. The parameters that were varied are the location and orientation of the building and various energy characteristics of windows/glazing.

  • 9.
    Dehlin, Stefan
    et al.
    NCC.
    Heikkilä, Katarina
    NCC.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Schade, Jutta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Racz, Tamas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Eriksson, Per-Erik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Effektive projektering av lågenergihus2011Report (Other academic)
    Abstract [sv]

    Byggbranschen står inför stora miljö- som affärsmässiga utmaningar med krav på att reducera energiförbrukning och miljöpåverkan. Detta projekt syftar till att bidra medkunskap hur energiprojektering kan effektiviseras vid nyproduktion avlågenergibyggnader där det övergripande målet är att stödja ett långsiktigt hållbart och lönsamt byggande. Studien har genomförts i samverkan mellan byggbransch och akademi genom fallstudier och enkätundersökningen.Resultatet visar på behovet och nyttan av att redan i tidigt planeringsskede utreda konsekvensen av olika alternativ av exempelvis byggnadsutformning ochklimatskärmens tekniska prestanda. Det spelar mindre roll vilket energiberäkningsverktyg man använder om resultatet används för att jämföra olika alternativ med varandra.Skillnaderna i krav och institutionella ramverk vad gäller energiprestanda påverkar också projektering av energieffektiva byggnader. En jämförande studie av hur man hanterar energifrågor från krav till färdig lösning mellan Tyskland och Sverige visar på ett behov av vidareutbildning i energifrågor för arkitekter och ingenjörer i Sverige som kommer in tidigt i byggprocessen. Undersökningen och jämförelsen pekar också mot ett behov av en sammanlänkande funktion, här kallad energisamordnare.Energisamordnarens roll är att föra in energikompetens in i projektet, säkerställa att krav och mål formuleras och hanteras samt aktivt delta i projekteringen för att guida utformningen av byggnaden mot en effektiv och låg energiförbrukning.Vi kan konstatera att det är marknadskrafter och engagemang från byggare, beställare och lokala myndigheter snarare än nationella krav som driverenergieffektivisering framåt i Sverige idag. Det kan emellertid leda till en situation där krav på energieffektivitet blir lokalt satta vilket kan leda till svårigheter för utvecklare av olika typer av byggnadssystem för bostäder och lokaler. Därför är det önskvärt att utvecklingen av byggnadstekniken som skett de senaste åren också följs upp av Boverket i form av krav som ligger i framkant snarare än minimikrav för att förhindra att en flora av lokala krav uppstår som kan verka som "handelshinder" för den fortsatta utvecklingen av det industriella byggandet i Sverige.Vi ser också ett tydligt behov för ökad samverkan och integration för att kunna driva energieffektiviseringen framåt men samtidigt också ett tydligt behov av att utveckla upphandlings- och samverkansformer för att möjliggöra detta. Upphandlingen, till exempel, bör utformas så att lämpliga aktörer väljs utifrån mjuka parametrar och involveras tidigt under projekteringsskedet samt ges ekonomiska incitamentkopplade till projektets mål, ekonomi och tidplan.Projektet har också undersökt hur man skall åstadkomma en mer integreradprojekteringsprocess genom att: Skapa en struktur för att samla, uttrycka och klargöra mål och krav ochutveckla dessa mot funktionskrav och tekniska lösningar. Genomföra en modellbaserad projektering som detaljerar tekniska lösningarallteftersom de utvecklas.Införa beslutsstöd för energifrågor i projektutveckling där produktensprestanda successivt jämförs mot funktionskrav med hjälp av alltmerdetaljerade prestandaanalyser.I projektet har också ett nyutvecklat formellt beslutsstöd exemplifierats där fleraalternativa lösningar kan utvärderas mot olika kriterier (MADM) vilka kanorganiseras och viktas hierarkiskt utifrån projektets mål och krav.I projektets har en prototyp, en så kallad energikonfigurator, utvecklats för atteffektivisera produkt och projektutveckling av s.k. konceptbyggande. Användandet har demonstrerats på NCC:s koncept P303 där man optimerat konfigureringen i produkt och projektutveckling efter både subjektiva och objektiva kriterier som tänkas efterlikna ett visst kundsegment. Hundratals alternativa utformningar kan utvärderas på några minuter i jämförelse med dagar och veckor om samma analyser skulle göras för hand med hjälp av energiberäkningsprogram med manuell inmatning av indata.För att effektivisera projekteringen mot ett energieffektivt byggande rekommenderar projektet att:Man tidigt upphandlar och involverar de viktigaste aktörerna så att man tidigtkan inkludera energiaspekter i utformning av koncept. Beställaren aktivt deltar i kravformuleringen och i analys- ochbeslutsprocessen. Dels för att säkerställa val mot uppställda krav och behovoch dels för att tillgodose de praktiska behov som uppstår i och med enintegrerad och modellbaserad projekteringsprocess. Utse en energisamordnare som skall säkerställa att formulerade energikravoch mål hanteras optimalt för att guida utformningen av byggnaden mot eneffektiv och låg energiförbrukning. Använda en modellbaserad projekteringsprocess för utformning, simuleringoch analys av konceptlösningar gentemot energirelaterade aspekter. Energianalyser som görs i tidigt skede används för att jämföra olikaalternativa utformningar. När detaljeringsnivån ökar bör man användadynamiska verktyg och för att beräkna energiförbrukning och inneklimat pårumsnivå. Man bör tidigt inkludera utformning av t ex ventilation ocheventuella maskinrum då de kan ha stor inverkan på energiförbrukningen. Man utför prestandaanalyser av energi och inneklimat innan man fryserdesign av klimatskärm och VVS så att resultatet kan guida konstruktörer ochinstallatörer i den slutliga utformningen av systemhandlingarna. Man i driftfasen utför en mer automatisk och kontinuerlig jämförelse mellansimulerad och verklig energiförbrukning för att bekräfta att byggnadenuppfyller initiala krav samt för att inhämta data och erfarenheter för vidareoptimering eller andra framtida projektFörändring sker i och med att beställaren möjliggör en miljö som initierar ochstödjer en hög grad av samverkan och integration mellan inblandade aktörer, därtyngden på beslutsfattandet flyttas till ett tidigare skede, där rätt kompetenserkan komma in vid rätt tillfälle och där fokus är på slutprodukten och desslivscykel och inte på avskilda åtaganden

  • 10. Dehlin, Stefan
    et al.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    A concurrent product development process using virtual prototypes2008Conference paper (Refereed)
  • 11.
    Dehlin, Stefan
    et al.
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    An evaluation model for ICT investments in construction projects2008In: Electronic journal of information technology in construction, ISSN 1403-6835, E-ISSN 1400-6529, Vol. 13, p. 343-361Article in journal (Refereed)
    Abstract [en]

    Even though Information and Communication Technology (ICT) investments in construction projects generally represent minor commitments of project resources by comparison to the full project cost, the value or impact on the profitability of the project are generally not considered. Also, many of the investment decisions are poorly thought through or examined. Investments decision taken during the procurement phase often merely based on intuition and rough estimations of the future costs and risks. Also, many of the traditionally used appraisal approaches have been shown inadequate in anticipating the consequences of such an investment. As a result, the investment is too often assumed to be negative since the benefits are not proper evaluated, included and weighted against the costs and risks the investment is expected to generate. Poor decision-basis does not only affect the actual decision-making in a particular project but also, in the long run, the motivation to innovate and to introduce new ICT tools and working methods into the construction industry. In view of this, a new project-oriented evaluation model is developed for the purpose to provide for a structure and a work routine to be used by a multidisciplinary project team to evaluate the implications of realizing ICT investments in construction projects. Although primarily aimed at establishing future benefits and costs the model may very well be used for follow-ups. The models' application is illustrated using a case study of a construction project using 3D and VR for coordination and evaluation. The results based on interviews and rough estimates on the "safe side" show that benefit of the ICT investment for the case study project was much higher compared with the cost for the project. The shift in focus from costs/benefits for the individual stakeholders to costs/benefits for the project gives a momentum to optimize the use of a new ICT tools in construction. This will surely affect the processes and the contractual environment in the project, since it has to support sharing of information and achieved benefits and the costs of the investment in the project.

  • 12. Elfgren, Lennart
    et al.
    Emborg, Mats
    Gabrielsson, Henrik
    Groth, Patrik
    Hedlund, Hans
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Jonasson, Jan-Erik
    Noghabai, Keivan
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Westman, Gustaf
    Design of high performance concrete structures in Sweden1998In: International Symposium on High-Performance and Reactive Powder Concretes: organized by Université de Sherbrooke / [ed] Pierre-Claude Aïtcin; Yves Delagrave, Sherbrooke, Que: University of Sherbrooke , 1998, p. 139-156Conference paper (Refereed)
  • 13.
    Elfgren, Lennart
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Noghabai, Keivan
    Ohlsson, Ulf
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Applications of fracture mechanics to anchors and bond1995In: Fracture mechanics of concrete structures: proceedings / [ed] Folker H. Wittmann, AEDIFICATIO Publishers , 1995, p. 1685-1694Conference paper (Refereed)
  • 14.
    Elfgren, Lennart
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Emborg, Mats
    Jonasson, Jan-Erik
    High performance concrete structures: a Swedish research program1996In: Concrete in the service of mankind. 4, Radical concrete technology: proceedings of the international conference held at the University of Dundee, Scotland, UK on 24-26 June 1996 / [ed] Ravindra K. Dhir; Peter C. Hewlett, London: Taylor and Francis Group , 1996, Vol. 4, p. 141-150Conference paper (Refereed)
  • 15.
    Emborg, Mats
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Jongeling, Rogier
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Dorbell, Thorbjörn
    Innovative construction with cast in place concrete using product models2004In: Concrete Structures: The Challenge of Creativity. Proceedings of FIB symposium on Concrete Structures, 2004, p. 220-221Conference paper (Refereed)
  • 16.
    Enochsson, Ola
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Bro över Luossajokk: övervakning för trafikering med 30 tons axellast2006Report (Other academic)
    Abstract [sv]

    I samband med projektet "30 ton på Malmbanan", Paulson-Töyrä (1996), konstaterades att bron över Luossajokk i Kiruna inte klarade de nya förhöjda lasterna. Bron har två spann och en utkragande konsol 10,25 + 6,3 + 3,4 m. Överbyggnaden utgörs av ett slak-armerat betongtråg med ett nytt mellanstöd som uppfördes 1965 då en äldre överbyggnad byttes ut. En klassningsberäkning och en utredning av förstärkningsbehov utfördes. Efter en förnyad översyn av brons bärförmåga utfördes töjningsmätningar vintern och sommaren 2001. Töjningsmätningarna indikerade förvånansvärt små påkänningar i bron. En närmare utredning av brons säkerhet att bära uppträdande laster utfördes 2002 genom en nyanserad säkerhetsberäkning med säkerhetsindexmetod. Bron bedömdes utifrån utredningen och mätresultat ha erforderlig bärförmåga om hastigheten begränsades så att eventuella dynamiska tillskott blir låga och/eller inverkan av ojämn temperatur försummas. Ett program med mätningar varje halvår igångsattes för att kontrollera brons fortsatta uppförande. Kontrollen bestod i en övervakning av aktuella töjningsnivåer i armeringen.I denna rapport redovisas resultat från mätningar mellan år 2001-2006. Resultaten visar ingen ökning av töjningsnivåerna fram till brons avlägsnande hösten 2006.

  • 17.
    Enochsson, Ola
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Kronborg, Anders
    Töyrä, B.
    Condition assessment of a concrete railway bridge in northern Sweden2006In: Condition Monitoring and Diagnostic Engineering Management: COMADEM 2006 / [ed] Uday Kumar; Aditya Parida; Raj B. K. N. Rao, Luleå: Luleå tekniska universitet, 2006, p. 711-719Conference paper (Refereed)
  • 18. Enochsson, Ola
    et al.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Täljsten, Björn
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Töyrä, Björn
    Banverket, Luleå.
    Kronborg, Anders
    Banverket, Luleå.
    Paulsson, Björn
    Banverket, Luleå.
    Assessment and condition monitoring of a concrete railway bridge in Kiruna, Sweden2006In: Bridge maintenance, safety, management, life-cycle performance and cost: Proceedings of the third International Conference on Bridge Maintenance, Safety and Management. IABMAS'06 / [ed] Paulo J. da Sousa Cruz; Dan M Frangopol; Luis C Canhoto Neves, London: Taylor and Francis Group , 2006Conference paper (Refereed)
    Abstract [en]

    A two-span railway concrete trough bridge over Luossajokk in Kiruna in northern Sweden has been studied. The owner wanted to increase the axle loads from 250 to 300 kN in order to reduce freight costs for iron ore. Examples are given of methods used and results obtained from the assessment where bending, shear and fatigue were studied. Material properties, loads and load carrying capacity were evaluated using deterministic and probabilistic methods. It was shown that the bridge could carry the higher loads with a safety index β > 4.7 for reasonable assumptions of the load distributions. A measurement system was installed to check the actual level of critical strains and the worst positions of the train. Results are also given from a condition monitoring program 2001-2006, launched to periodically check the development of strains with time

  • 19.
    Enochsson, Ola
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Hejll, Arvid
    Nilsson, Martin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Thun, Håkan
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Elfgren, Lennart
    Bro över Luossajokk: beräkning med säkerhetsindexmetod, böjdragkapacitet i överkant i mittsnittet i korta spannet2002Report (Other academic)
    Abstract [sv]

    I samband med projektet "30 ton på Malmbanan", Paulson-Töyrä (1996), konstaterades att bron över Luossajokk i Kiruna inte klarade de nya förhöjda lasterna. Bron har två spann och en utkragande konsol 10,25 + 6,3 + 3,4 m. Överbyggnaden utgörs av ett slakarmerat betongtråg med ett nytt mellanstöd som uppfördes 1965 då en äldre överbyggnad byttes ut. En klassningsberäkning och en utredning av förstärkningsbehov utfördes. Efter en förnyad översyn av brons bärförmåga utfördes töjningsmätningar vintern och sommaren 2001. Töjningsmätningarna indikerade förvånansvärt små påkänningar i bron. En närmare utredning av brons säkerhet att bära uppträdande laster genomförs därför i denna rapport. Detta sker med hjälp av en nyanserad säkerhetsberäkning med säkerhetsindexmetod. Den nya genomgången visar att medelvärdet för bärförmågan för moment är 2,89 MNm med standardavvikelsen 0,19 MNm i det mest utsatta snittet med dragpåkänningar i överkant i korta spannet. Detta kan jämföras med det formella dimensioneringsvärdet 1,99 MNm som erhölls i klassningsberäkningen med beaktande av aktuella partialkoefficienter. I det nya medelvärdet har en lägre uppmätt effektiv höjd beaktats, att ett av tolv armeringsjärn borrats av samt att betong- och armeringshållfastheterna är högre än de nominella dimensioneringsvärdena. På lastsidan gav klassningsberäkningen i motsvarande snitt att det formella dimensioneringsvärdet för momentet är 2,79 MNm. En analys av verkliga uppträdande laster ger att medelvärdet maximalt uppgår till 2,05 MNm. Detta lastfall utgörs av ett lok placerat med tre axlar i längsta spannet och tre axlar placerade på konsolen, om såväl bromslast som ojämn temperaturlast och dynamiskt tillskott uppträder samtidigt. Enligt BV Bärighet (1996) behöver ojämn temperatur inte beaktas, vilket är rimligt med tanke på att detta är ett statiskt obestämt lastfall som försvinner vid uppsprickning i brottstadiet. Det har heller inte medräknats i tidigare klassningsberäkningar. I så fall fås att lasten har medelvärdet 1,66 MNm och att säkerhetsindex β varierar mellan 3,8 och 6,0 beroende på vilka antaganden som görs om lasternas statistiska fördelning. För en rimlig fördelning innehålls kravet i säkerhetsklass 3 att säkerhetsindex β 4,75. Bron visar sig därför, enligt vår bedömning och med beaktande av erhållna mätresultat, ha erforderlig bärförmåga om hastigheten begränsas på bron så att eventuella dynamiska tillskott blir låga och/eller inverkan av ojämn temperatur försummas. Brons fortsatta uppförande bör kontrolleras genom ett mätprogram. Detta bör förutom armeringstöjningar med befintliga givare även inkludera mätningar av nedböjningar för att säkerställa att använda beräkningsmodeller och randvillkor på ett korrekt sätt återger brons beteende. Storleken på den dynamiska förstoringsfaktorn D bör även mätas liksom inverkan av bromskrafter och ojämn temperaturfördelning. På så sätt kan ett säkrare underlag erhållas för bedömning av frekvensfunktionerna för dessa vanliga lasteffekter. Dessa värden borde även vara av intresse vid säkerhetsbedömning av likartade järnvägsbroar.

  • 20.
    Enochsson, Ola
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Lundqvist, Joakim
    Täljsten, Björn
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Rusinowski, Piotr
    Technical University of Denmark.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    CFRP strengthened openings in two-way concrete slabs: an experimental and numerical study2007In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 21, no 4, p. 810-826Article in journal (Refereed)
    Abstract [en]

    Rehabilitation and strengthening of concrete structures with externally bonded fibre reinforced polymers (FRPs) has been a viable technique for at least a decade. An interesting and useful application is strengthening of slabs or walls where openings are introduced. In these situations, FRP sheets are very suitable; not only because of their strength, but also due to that they are easy to apply in comparison to traditional steel girders or other lintel systems. Even though many benefits have been shown by strengthening openings with FRPs not much research have been presented in the literature. In this paper, laboratory tests on 11 slabs with openings, loaded with a distributed load are presented together with analytical and numerical evaluations. Six slabs with openings have been strengthened with carbon fibre reinforced polymers (CFRPs) sheets. These slabs are compared with traditionally steel reinforced slabs, both with (four slabs) and without openings (one slab). The slabs are quadratic with a side length of 2.6 m and a thickness of 100 mm. Two different sizes of openings are used, 0.85 × 0.85 m and 1.2 × 1.2 m. The results from the tests show that slabs with openings can be strengthened with externally bonded CFRP sheets. The performance is even better than for traditionally steel reinforced slabs. The numerical and analytical evaluations show good agreement with the experimental results.

  • 21. Enochsson, Ola
    et al.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Täljsten, Björn
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    CFRP Strengthened openings in two-way concrete slabs2005In: FRP composites in civil engineering - CICE 2004: Proceedings of the Second International Conference on FRP Composites in Civil Engineering / [ed] Rudolf Seracino, Leiden: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 2005Conference paper (Refereed)
  • 22. Enochsson, Ola
    et al.
    Puurula, Arto
    Stenlund, Anders
    Thun, Håkan
    Nilsson, Martin
    Täljsten, Björn
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Condition assessment of concrete bridges in Sweden2005In: Concrete repair, rehabilitation and retrofitting / [ed] Mark G. Alexander; Hans-Dieter Beushausen; Frank Dehn; Pilate Moyo, London: Taylor and Francis Group , 2005, p. 257-259Conference paper (Refereed)
    Abstract [en]

    Examples are given of methods used and results obtained from two bridges assessed in Sweden. The following sectional forces were critical: (a) Bending, shear and fatigue in a two-span railway trough bridge and (b) Shear and torsion in a three-span prestressed cantilever box girder road bridge. In the assessments we evaluated material properties, loads and load carrying capacity using deterministic and probabilistic methods

  • 23. Enochsson, Ola
    et al.
    Täljsten, Björn
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Structural health monitoring of a concrete bridge in Sweden2006In: Proceedings of SPIE, the International Society for Optical Engineering, ISSN 0277-786X, E-ISSN 1996-756X, Vol. 6176, no 18Article in journal (Refereed)
    Abstract [en]

    Over the past decade the interests in upgrading, assessment and maintenance of our ageing infrastructure has grown avalanche-like. The main reason is economical aspects but also reasons due to accessibility environmental consideration play a vital role. Recently the Swedish and Norwegian Railway Association decided to upgrade the Iron Ore Line "Malmbanan", a railway line for transportation of iron from northern Sweden to the coasts of Norway and Sweden. Here the owner wanted to increase the axle loads from 25 to 30 tons to reduce the transportation costs. In one of the cases, the Luossajokk Bridge, a recalculation according to design codes showed that the increased axle loads would exceed the yield limit in the reinforcement. Before any decision was taken regarding strengthening or replacing the bridge an assessment with probabilistic methods was used. It appeared that the bridge could carry the higher load with a safety index β ≥ 4.7 for reasonable assumptions of the load distributions. A measurement system was installed to check the real worst placement of the new iron ore locomotive (IORE), and the actually level of strains in the reinforcement for the worst load case1. It was shown that the strain level was far from critical and that the evaluated worst placement of the locomotive was almost correct2. To assure a reliable transportation a long term monitoring program was arranged to check the development of strains with time. Examples from the probabilistic evaluation and the monitoring of the bridge are given and discussed.

  • 24.
    Erikshammar, Jarkko
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Stehn, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Discrete event simulation enhanced value stream mapping: an industrialized construction case study2013In: Lean Construction Journal, ISSN 1555-1369, E-ISSN 1555-1369, Vol. 10, p. 47-65Article in journal (Refereed)
    Abstract [en]

    Research Question/Hypothesis: Can a production process design framework created by integrating Value Stream Mapping (VSM) and Discrete Event Simulation (DES) be used to assess the production system performance, as predicted by a future state design of small and medium sized enterprises (SMEs) working in industrialized construction?Purpose: To explore a production process design framework in which VSM is used to identify doable improvements and DES provides analytical evaluation of them.Research Method: The demonstration was carried out at a Swedish SME industrialized construction component manufacturerFindings: VSM is unable to evaluate analytically the performance of the future state design. This inability leads to unnecessary implementation iterations. VSM assumes a deterministic model and cannot describe the dynamic behaviors of a system. The dynamic behavior of the construction processes will result in the future state design not performing as expected. However, by analytically evaluating the future state with DES helped the case company to implement a new production process design.Limitations: DES modeling is still time-consuming and needs skilled professionals, the cost of whom can be prohibitive for SMEs and demonstrated in one case study.Implications: The integration of DES and VSM provides a framework to evaluate and communicate the outcome, hence enhancing the application of VSM.Value for practitioners: A lean framework, which can be used, for industrialized construction processes especially by SMEs with very limited resources, to validate changes before implementing them.

  • 25.
    Eriksson, Per-Erik
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Szentes, Henrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Lagerqvist, Ove
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Hinder och drivkrafter för industriellt anläggningsbyggande: Underlagsrapport till Produktivitetskommittén, Näringsdepartementet2012Report (Other academic)
  • 26.
    Feng, Kailun
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction. Department of Construction Management, Harbin Institute of Technology, Harbin, 150001, China.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Chen, Shiwei
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering. Department of Construction Management, Harbin Institute of Technology, Harbin, 150001, China.
    Yan, Hui
    School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, 510641, China.
    Wang, Yaowu
    Harbin Institute of Technology, Information Technology Institute, Harbin, China.
    A predictive environmental assessment method for construction operations: Application to a Northeast China case study2018In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, no 11, article id 3868Article in journal (Refereed)
    Abstract [en]

    Construction accounts for a considerable number of environmental impacts, especially in countries with rapid urbanization. A predictive environmental assessment method enables a comparison of alternatives in construction operations to mitigate these environmental impacts. Process-based life cycle assessment (pLCA), which is the most widely applied environmental assessment method, requires lots of detailed process information to evaluate. However, a construction project usually operates in uncertain and dynamic project environments, and capturing such process information represents a critical challenge for pLCA. Discrete event simulation (DES) provides an opportunity to include uncertainty and capture the dynamic environments of construction operations. This study proposes a predictive assessment method that integrates DES and pLCA (DES-pLCA) to evaluate the environmental impact of on-site construction operations and supply chains. The DES feeds pLCA with process information that considers the uncertain and dynamic environments of construction, while pLCA guides the comprehensive procedure of environmental assessment. A DES-pLCA prototype was developed and implemented in a case study of an 18-storey building in Northeast China. The results showed that the biggest impact variations on the global warming potential (GWP), acidification potential (AP), eutrophication (EP), photochemical ozone creation potential (POCP), abiotic depletion potential (ADP), and human toxicity potential (HTP) were 5.1%, 4.1%, 4.1%, 4.7%, 0.3%, and 5.9%, respectively, due to uncertain and dynamic factors. Based on the proposed method, an average impact reduction can be achieved for these six indictors of 2.5%, 21.7%, 8.2%, 4.8%, 32.5%, and 0.9%, respectively. The method also revealed that the material wastage rate of formwork installation was the most crucial managing factor that influences global warming performance. The method can support contractors in the development and management of environmentally friendly construction operations that consider the effects of uncertainty and dynamics.

  • 27.
    Fransson, Lennart
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    On scaling of the maximum ice pressure on a vertical foundation2005In: Proceedings of the 18th International Conference on Port and Ocean Engineering under Arctic Conditions: POAC '05, 2005, Vol. 1, p. 341-351Conference paper (Refereed)
  • 28.
    Fransson, Lennart
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Holm, Ingvar
    Istryck mot en bropelare i Lule älv, vintern 1981/821982Report (Other academic)
  • 29.
    Fransson, Lennart
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Sandkvist, Jim
    Luleå tekniska universitet.
    Observations of the failure process in ice blocks crushed by a flat indentor1991In: POAC '91: 11th International conference on port and ocean engineering under arctic conditions : Papers / [ed] D B Muggeridge; D B Colbourne; H M Muggeridge, St. John's, N.L: St Johns University , 1991, Vol. 1, p. 501-514Conference paper (Refereed)
  • 30.
    Gabrielsson, Henrik
    et al.
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Seghet i högpresterande betongkonstruktion1996In: Byggforskning : Byggforskningsrådets tidning för en bättre byggd miljö, ISSN 1102-3686, no 3, p. 42-Article in journal (Other (popular science, discussion, etc.))
  • 31.
    Godonou, Patrice
    et al.
    Luleå tekniska universitet.
    Liljenfeldt, Lars
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Development and conceptual design of a pedestrian bridge using fibre reinforced composites2000In: Advanced composite materials in bridges and structures / [ed] J. L. Humar, Montréal: Canadian Society for Civil Engineering , 2000, p. 339-345Conference paper (Refereed)
  • 32.
    Godonou, Patrice
    et al.
    Luleå tekniska universitet.
    Liljenfeldt, Lars
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Preliminary design analysis of a pedestrian FRP bridge deck using sandwich construction2000In: Proceedings of the 3rd Nordic Meeting on Materials and Mechanics: 8-11 May 2000 / [ed] Ryszard Pyrz; Nikolaj Vejen; Jan Schjødt-Thomsen, Aalborg: Inst of mechanical engineering, Aalborg university , 2000, p. 175-180Conference paper (Refereed)
  • 33.
    Groth, Patrik
    et al.
    Luleå tekniska universitet.
    Jonasson, Jan-Erik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Brottmekanisk modellering av sprickbildning i ung betong2000In: Bygg & Teknik, ISSN 0281-658X, no 7, p. 27-28Article in journal (Other (popular science, discussion, etc.))
  • 34.
    Groth, Patrik
    et al.
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Size effects on flexural toughness of steel fibre reinforced concrete1997In: Advanced design of concrete structures: [papers presented at the Symposium on Advanced Design of Concrete Structures, held in Chalmers University of Technology in Göteborg, Sweden on June 12 - 14, 1997] / [ed] Kent Gylltoft, Barcelona: International Center for Numerical Methods in Engineering (CIMNE), 1997, p. 271-278Conference paper (Refereed)
  • 35. Hehenberger, Michael
    et al.
    Samuelsson, Peter
    Nilsson, Larsgunnar
    Högskolan i Luleå.
    Alm, Ove
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    On the compaction of hard metal powders: preliminary experimental and theoretical studies1980Report (Other academic)
  • 36.
    Jansson, Gustav
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Lundkvist, Robert
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    The role of experience feedback channels in the continuous development of house-building platforms2015In: Construction Innovation, ISSN 1471-4175, E-ISSN 1477-0857, Vol. 15, no 2, p. 236-255Article in journal (Refereed)
    Abstract [en]

    PurposeHouse-building companies seek improvements to decrease costs, improve flow, and decrease variability. Industrialised concepts using predefinitions in product platforms have provided a way of storing and reusing knowledge in project-based house-building organisations. However, the innovation in platforms is mainly incremental and based on experience feedback (EF) from implementations in projects. This paper aims to describe how the EF from building projects contributes to product platform development in house building companies.Design/methodology/approachQualitative data were gathered via interviews, archival studies and observations, and analysed to identify the underlying structures used to manage the incorporation of EF during platform development. Four different EF channels were studied at one Scandinavian house-builder. The data are explained using an analytical framework based on diffusion of innovation, product platforms and EF.FindingsEF is distributed over the value chain to improve the platform over time. By using multiple channels with differing contents, it is possible to balance client demands and variation with production efficiency. Platform development using feedback channels provides opportunities for double-loop learning. Operative work on projects and the strategic decisions made by developers continuously improve the platform through a combination of knowledge pull and push.Originality/valueA combination of different EF channels and strategies for developing knowledge pull are shown to be essential for the incremental development of product platforms in project-based house building organisations. The development of product platforms requires a shift away from the construction industry’s dominant project focus towards a more product-oriented view of house-building. Integrating the design phase with the supply chain enables variety but also creates a need for continuous platform development

  • 37.
    Jansson, Gustav
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Mukkavaara, Jani
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Interactive visualization for information flow in production chains: Case study industrialised house-building2018In: Proceedings of the 35th ISARC, Berlin, Germany, IAARC Publications , 2018, Vol. 35, p. 382-388Conference paper (Refereed)
    Abstract [en]

    Predefinitions in house-building platforms is developed as routines to manage project building information models over to production data by documents and digital drawings. Visualisation of the information flow in the industrialised house-building process is hard to track and information are often presented as islands, seldom described in the flow for the entire process. Interactive visualisation, using game technology, has open up for new applications of data -transformation, -visualization and -simulation of project information which is less studied in the context of industrialised house-building. This paper tries to address this issue via a combination of game engine technology and the predefined industrialised house-building process. The game engine technology allow development for end -user demands and functionality to express and visualise values for the daily planning and execution of processes. In a case study approach the development and analysis of four building projects were studied and chosen to the range of product platform predefinitions. Based on object structure for different views, models and the related metadata were visualised with an immersive virtual environment prototype. The prototype, based on game engine technology, was developed to manage incoming building projects variations that followed house-building platform predefinitions. As a visualising tool of engineering, on-site planning and production process the game engine technology simulates and visualize views on product structures, production information, assembling and operation instructions by interactive functions in the game environment.

  • 38.
    Jansson, Gustav
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Schade, Jutta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Requirements management for the design of energy efficient buildings2013In: Journal of Information Technology in Construction (ITcon), ISSN 1874-4753, E-ISSN 1874-4753, Vol. 18, p. 321-337Article in journal (Refereed)
    Abstract [en]

    Buildings are designed to fulfil the multiple and, often, contradictory requirements of users, clients and society. Energy aspects are often not considered before the detailed design phase and a systematic way of analysing the energy performance of solutions throughout the design phase is lacking. A suggested framework, based on engineering design theories of requirements management, was applied to a case study of the design of an energy-efficient building in a real construction project. The case study provided qualitative insights into how the proposed framework can contribute to a more structured requirements management of a construction project with a focus on the energy-efficient design of buildings. It can be seen that the proposed framework for requirements management of energy performance provides a structure for designers to consider and apply energy performance criteria in the early design stages and visualize the consequences of alternative design solutions for clients, engineers, contractors and suppliers. The use of a requirements structure enables the transparency of different design alternatives against the established functional requirements of energy performance for the stakeholders in the design process. The use of BIM to support the proposed requirements framework needs to be studied further and connected to national and international construction classification schemas and ontology frameworks.

  • 39.
    Jansson, Gustav
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Schade, Jutta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Tarandi, Väino
    Eurostep AB.
    Requirements transformation in construction design2010In: CIB W78 27th International Conference on Applications of IT in the AEC Industry & Accelerating BIM Research Workshop, 2010Conference paper (Other academic)
    Abstract [en]

    Transformation of performance requirements to technical solutions and production parameters is central for architects and engineers in the design process. Construction industry suffers from low efficiency in design, and the information flow creating bottlenecks for the production process. Tracing and managing information through design process needs standards both for requirements and Building Information Models in a life cycle perspective. Structuring functional requirements is of great interest for the construction industry and especially for companies developing industrialised housing system that often have control over the whole manufacturing process. The delivery of a new low-carbon economy in Europe puts pressure on the construction industry to reduce the energy consumption for buildings. Therefore is one national standard for energy requirements tested on a building system and evaluated in an Information and Communication Technology-environment (ICT) that supports the design process for industrialised construction. The result of the research shows that the transformation of requirements to technical solutions needs functionality that supports the design process by using standards for requirements. A rigid building system based on well defined design tasks together with a technical platform, both for spaces and physical elements, work as a backbone for development of ICT support systems. Product Life Cycle Support (PLCS), as a standard that enables flexibility in categorisation of information through the construction design. Keywords: Requirements transformation, energy standards, BIM support, PLCS, construction design

  • 40.
    Jansson, Gustav
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Viklund, Emma
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Artistic and Engineering Design of Platform-Based Production Systems: A Study of Swedish Architectural Practice2018In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 8, no 2, article id 34Article in journal (Refereed)
    Abstract [en]

    Research on platform-based production systems for house-building has focused on production and manufacturing issues. The aim of this research is to explore how the architectural design process contributes to the industrialised house-building industry from the perspective of creative design work. It also aims to describe how constraints affect architectural design work in the engineer-to-order context, when using platform-based production systems. Architects with experience in using platform-based building systems with different degrees of constraints were interviewed regarding creative aspects of the design work. The interviews, together with documents relating to platform constraints, were then analysed from the perspective of artistic and engineering design theories. The results show the benefits and issues of using platform constraints, both with prefabrication of volumetric modules, as well as prefabricated slab and wall elements. The study highlights a major research gap by describing how architectural work, from both the creative artistic and engineering design perspectives, is affected by constraints in the building platform: (1) the architectural design work goes through a series of divergent and convergent processes where the divergent processes are explorative and the convergent processes are solution-oriented; and (2), there is a trade-off between creativity and efficiency in the design work. Open parameters for layout design are key to architectural creativity, while predefinition supports efficiency. The results also provide an understanding of the potential for creativity in artistic and engineering work tasks through different phases in design, and how they are related to constraints in the platform. The main limitation of the research is the number of interviewed architects who had different background experiences of working with different types of platform constraints. More studies are needed to confirm the observations and to understand how creativity and efficiency interact with divergent and convergent design processes.

  • 41.
    Jassim, Hassanean
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Krantz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    A Cradle-to-Gate Framework for Optimizing Material Production in Road Construction2016In: 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, no 19, p. 758-764Conference paper (Refereed)
    Abstract [en]

    Abstract

    In road construction, large quantities of raw materials are extracted and transported duringseveral stages of its life cycle. Consequently, processing and preparation of raw materials fordifferent purposes inevitably result in considerable amount of energy use and emissions of airpollutants. The Swedish Transportation Administration has an ambition to minimizeenvironmental impacts from transport infrastructure projects by, for instance, reducing the energyuse and emissions of greenhouse gases. This can be achieved by implementing specific strategiesand techniques during various stages throughout the life cycle of the project. In this paper aframework is proposed to manage the energy use and greenhouse gases emissions from rawmaterials extraction processes in road construction projects. A prototype is developed based onthe framework and demonstrated in a small case study.

  • 42.
    Jassim, Hassanean
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Predicting energy consumption and CO2 emissions of excavators in earthwork operations: An artificial neural network model2017In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, no 7, article id 1257Article in journal (Refereed)
    Abstract [en]

    Excavators are one of the most energy-intensive elements of earthwork operations. Predicting the energy consumption and CO2 emissions of excavators is therefore critical in order to mitigate the environmental impact of earthwork operations. However, there is a lack of method for estimating such energy consumption and CO2 emissions, especially during the early planning stages of these activities. This research proposes a model using an artificial neural network (ANN) to predict an excavator's hourly energy consumption and CO2 emissions under different site conditions. The proposed ANN model includes five input parameters: digging depth, cycle time, bucket payload, engine horsepower, and load factor. The Caterpillar handbook's data, that included operational characteristics of twenty-five models of excavators, were used to develop the training and testing sets for the ANN model. The proposed ANN models were also designed to identify which factors from all the input parameters have the greatest impact on energy and emissions, based on partitioning weight analysis. The results showed that the proposed ANN models can provide an accurate estimating tool for the early planning stage to predict the energy consumption and CO2 emissions of excavators. Analyses have revealed that, within all the input parameters, cycle time has the greatest impact on energy consumption and CO2 emissions. The findings from the research enable the control of crucial factors which significantly impact on energy consumption and CO2 emissions.

  • 43.
    Jassim, Hassanean
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction. Babylon University.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Quantification of Energy Consumption and Carbon Dioxide Emissions During Excavator Operations2018In: Advanced Computing Strategies for Engineering: 25th EG-ICE International Workshop 2018, Lausanne, Switzerland, June 10-13, 2018, Proceedings, Part I, Cham, 2018, p. 431-453Conference paper (Refereed)
    Abstract [en]

    A number of studies have assessed the energy consumed and carbon dioxide emitted by construction machinery during earthwork operations. However, little attention has been paid to predicting these variables during planning phases of such operations, which could help efforts to identify the best options for minimizing environmental impacts. Excavators are widely used in earthwork operations and consume considerable amounts of fuel, thereby generating large quantities of carbon dioxide. Therefore, rigorous evaluation of the energy consumption and emissions of different excavators during planning stages of project, based on characteristics of the excavators and projects, would facilitate selection of optimal excavators for specific projects, thereby reducing associated environmental impacts. Here we describe use of artificial neural networks (ANNs), developed using data from Caterpillar’s handbook, to model the energy consumption and CO2 emissions of different excavators per unit volume of earth handled. We also report a sensitivity analysis conducted to determine effects of key parameters (utilization rate, digging depth, cycle time, bucket payload, horsepower, load factor, and hauler capacity) on excavators’ energy consumption and CO2 emissions. Our analysis shows that environmental impacts of excavators can be most significantly reduced by improving their utilization rates and/or cycle times, and reducing their engine load factor. We believe our ANN models can potentially improve estimates of energy consumption and CO2 emissions by excavators. Their use in planning stages of earthworks projects could help planners make informed decisions about optimal excavator(s) to use, and contractors to evaluate environmental impacts of their activities. Finally, we describe a case study, based on a road construction project in Sweden, in which we use empirical data on the quantities and nature of the materials to be excavated, to estimate the environmental impact of using different excavators for the project

  • 44.
    Jassim, Hassanean S. H.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    A Practical Method for Assessing the Energy Consumption and CO2 Emissions of Mass Haulers2016In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 10, article id 802Article in journal (Refereed)
    Abstract [en]

    Mass hauling operations play central roles in construction projects. They typically use many haulers that consume large amounts of energy and emit significant quantities of CO2. However, practical methods for estimating the energy consumption and CO2 emissions of such operations during the project planning stage are scarce, while most of the previous methods focus on construction stage or after the construction stages which limited the practical adoption of reduction strategy in the early planning phase. This paper presents a detailed model for estimating the energy consumption and CO2 emissions of mass haulers that integrates the mass hauling plan with a set of predictive equations. The mass hauling plan is generated using a planning program such as DynaRoad in conjunction with data on the productivity of selected haulers and the amount of material to be hauled during cutting, filling, borrowing, and disposal operations. This plan is then used as input for estimating the energy consumption and CO2 emissions of the selected hauling fleet. The proposed model will help planners to assess the energy and environmental performance of mass hauling plans, and to select hauler and fleet configurations that will minimize these quantities. The model was applied in a case study, demonstrating that it can reliably predict energy consumption, CO2 emissions, and hauler productivity as functions of the hauling distance for individual haulers and entire hauling fleets.

  • 45.
    Jassim, Hassanean S.H.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction. Department of Civil Engineering, College of Engineering, University of Babylon.
    Lu, Weizhuo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Assessing energy consumption and carbon dioxide emissions of off-highway trucks in earthwork operations: an artificial neural network model2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, p. 364-380Article in journal (Refereed)
    Abstract [en]

    Methods capable of predicting the energy use and CO2 emissions of off-highway trucks, especially in the initial planning phase, are rare. This study proposed an artificial neural networks (ANN) model to assess such energy use and CO2 emissions for each unit volume of hauled materials associated with each hauling distance. Data from discrete event simulations (DES), an off-highway truck database, and different site conditions were simultaneously analyzed to train and test the proposed ANN model. Six independent quantities (i.e., truck utilization rate, haul distance, loading time, swelling factor, truck capacity, and grade horsepower) were used as the input parameters for each model. The developed model is an efficient tool capable of assessing the energy use and CO2 emissions of off-highway trucks in the initial planning stage. The results revealed that the grade horsepower and haul distances yield a significant increase in the environmental impact of the trucks. In addition, the results demonstrated that, for a given set of project conditions, the environmental impact of trucks can reduced by improving their utilization rate and reducing the loading time.

  • 46. Jensen, Patrik
    et al.
    Hamon, Emile
    Tyréns AB.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Product development through lean design and modularization principles2009In: Proceedings IGLC 17: 17th Annual Conference of the International Group for Lean Construction, 2009, p. 465-474Conference paper (Refereed)
    Abstract [en]

    Customers' demands regarding quality and cost efficiency caused the Swedish construction industry to increase its levels of prefabrication. However, the main focus has been on the structural design and production in the development of these new building systems, and very little attention has been devoted to customer needs and requirements. This has created a situation where ad hoc solutions have been introduced to adapt the building system to match the project requirements, causing problems in the production process with waste and quality problems as a result.Therefore, a development project was initiated with the goal to design a new building system for multi-story timber housing that could match the client needs and requirements. This paper describes how this development process was pursued using lean design methods and modularization principles. A multi-skilled development team worked for over 6 months in developing a technical and a process platform for a flexible building system. The study shows that it is evident that modularization principles can be used in order to develop flexible building systems that better can match the requirements from an individual project. From a set of rules, the architect can configure and design a unique building which enables the manufacturability of the building system and ensures a smooth assembly process of the prefabricated modules on the construction site.

  • 47.
    Jensen, Patrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Johansson, Tim
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Smiding, Erik
    Tyréns AB.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Product configuration of roundabouts2013In: Proceedings of the 30th CIB W78 International Conference, 2013, p. 1-10Conference paper (Refereed)
    Abstract [en]

    The purpose of this study is to develop methods in the design of roundabouts that can be used in early conceptual phases of infrastructural projects to avoid erroneous solutions propagating downstream the value chain. Adapting theory and principals from mass customization and design configuration, a configurator for roundabouts to be used in early phases was developed and validated in a live project. The configurator is built in SolidWorks and parametrically coupled to the use of Tacton Studio. The configurator generates a drawing and a protocol that informs the user of the chosen configuration and where it doesn’t conform to the Swedish standards.In conclusion, it is possible to use theories from mass customization to develop configurators that can simplify the design process and thus evaluating the design according to norms and standards in early phases of the project. In the search for increased efficiency within infrastructural projects, parametric modeling configurators can be used to speed up the design process and expand the range of alternatives that can be generated. In that sense, this article contributes to the understanding of how mass customization principles in general can be used in construction and how it can be implemented in the design of specific projects.

  • 48.
    Jensen, Patrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Larsson, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Simonsson, Peter
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Improving buildability with platforms and configurators2013In: Proceedings IGLC-21: Conference of the International Group for Lean Construction / [ed] Carlos T. Formoso; Patricia Tzortzopoulos, Fortaleza, Brazil, 2013, p. 771-780Conference paper (Refereed)
    Abstract [en]

    The different stages in construction projects are often separated with little interaction between the different trades. Many researchers proclaim that this separation between design and production limits the buildability of construction designs. Thus there is a need for providing knowledge of rules and constraints imposed from production in the design of construction products. A way of integration of production knowledge in the design is by implementing product platforms and configurators in construction projects. This paper describes the development of a configurator for a modularized concrete bridge that can be produced efficiently. Production of bridges can be selected to be built either on site or prefabricated. Previous work to develop configurators has mainly focused on the efficiency of the design phase and is usually not linked to production improvements and simplifications. By defining the product platform for a certain bridge variant within its market segment, the technical solutions can be designed to be flexible while ensuring the buildabuility in the construction phase.The developed configurator is built in SolidWorks and parametrically coupled using Tacton Studio. The first version generates geometrical drawings. Whereas validation show that parametric modelling configurators can be used for increasing buildability and efficiency at site, and also increasing the range of feasible alternatives and for speeding up the design process.

  • 49.
    Jensen, Patrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Lidelöw, Helena
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Product Configuration in Construction2015In: International Journal of Mass Customisation, ISSN 1742-4208, Vol. 5, no 1, p. 73-92Article in journal (Refereed)
    Abstract [en]

    Construction is traditionally a trade that produces unique, one-off products designed specifically for the project in an engineer-to-order process. However, the development of flexible product platforms, based on the theory of mass customization, can offer product flexibility with affordable costs. The degree of commonality can also be increased if applying the products-in-products concept. This study aims to conceptualize and test theories of mass customization through modularization for applications in the construction industry. This is examined for three cases, with different specification processes (modify-to-order, configure-to-order and select-variant) incorporating bothbuilding and infrastructure products. The results show that the products-in-products concept is useful for enabling mass customization in construction. While the design can be integral in the select-variant type of specification process, the architecture needs to have a modular structure to enable a modify-to-order or configure-to-order type of customization.

  • 50.
    Jensen, Patrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Johnsson, Helena
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Configuration through the parameterization of building components2012In: Automation in Construction, ISSN 0926-5805, E-ISSN 1872-7891, Vol. 23, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Many construction companies have developed building systems, based on prefabrication strategies, to enhance productivity. Current practice coupled with the difficulties of introducing these systems early in the design process often leads to ad hoc solutions and problems downstream along the value chain. In 2008 a multi-storey timber building system based on modularization principles was developed. The customization process used in this system is illustrated herein using a configurable timber floor slab module. The downstream flow of design information and upstream flow of constraints on, and rules for, the building system are described from three product viewpoints: the customer view, the engineering view and the production view. Using a manufacturing CAD tool, design automation is implemented in the engineering view and connected to an architectural CAD tool. The demonstration software shows that manufacturing CAD tools can be used to create design automation alternatives for modularized building systems within the construction industry.

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