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  • 1.
    Jassim, Hassanean
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Krantz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande. Luleå University of Technology.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    A Model to Reduce Earthmoving Impacts2019Artikel i tidskrift (Refereegranskat)
  • 2.
    Jassim, Hassanean
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Determining the environmental impact of material hauling with wheel loaders during earthmoving operations2019Ingår i: Journal of the Air and Waste Management Association, ISSN 1096-2247, E-ISSN 2162-2906Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A method has been developed to estimate the environmental impact of wheel loaders used in earthmoving operations. The impact is evaluated in terms of energy use and emissions of air pollutants (CO2, CO, NOx, CH4, VOC, and PM) based on the fuel consumption per cubic meter of hauled material. In addition, the effects of selected operational factors on emissions during earthmoving activities were investigated to provide better guidance for practitioners during the early planning stage of construction projects. The relationships between six independent parameters relating to wheel loaders and jobsite conditions (namely loader utilization rates, loading time, bucket payload, horsepower, load factor, and server capacity) were analyzed using artificial neural networks, machine performance data from manufacturer’s handbooks, and discrete event simulations of selected earthmoving scenarios. A sensitivity analysis showed that the load factor is the largest contributor to air pollutant emissions, and that the best way to minimize environmental impact is to maximize the wheel loaders’ effective utilization rates. The new method will enable planners and contractors to accurately assess the environmental impact of wheel loaders and/or hauling activities during earthmoving operations in the early stages of construction projects.

    Implications: There is an urgent need for effective ways of benchmarking and mitigating emissions due to construction operations, and particularly those due to construction equipment, during the pre-construction phase of construction projects. Artificial Neural Networks (ANN) are shown to be powerful tools for analyzing the complex relationships that determine the environmental impact of construction operations and for developing simple models that can be used in the early stages of project planning to select machine configurations and work plans that minimize emissions and energy consumption. Using such a model, it is shown that the fuel consumption and emissions of wheel loaders are primarily determined by their engine load, utilization rate, and bucket payload. Moreover, project planners can minimize the environmental impact of wheel loader operations by selecting work plans and equipment configurations that minimize wheel loaders’ idle time and avoid bucket payloads that exceed the upper limits specified by the equipment manufacturer.

  • 3.
    Krantz, Jan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Feng, Kailun
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande. Department of Construction Management, Harbin Institute of Technology, Harbin, China.
    Larsson, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    ‘Eco-Hauling’ Principles to Reduce Carbon Emissions and the Costs of Earthmoving: a Case Study2019Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 208, s. 479-489Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mitigating emissions of carbon dioxide and other greenhouse gases is critical if we are to meet the increasing threats posed by global warming. Previous studies have shown conclusively that a substantial part of all carbon dioxide emissions comes from transportation, and that Eco-Driving principles based upon strategic, tactical, and operational decisions have the potential to reduce these emissions. However, these well-established principles have been neglected within the construction industry despite the large number of transport-related activities that attend most construction projects. This paper therefore aims to increase awareness and understanding within the industry of the potential reductions of both carbon dioxide emissions and the costs of earthmoving activities that could be achieved through the use of Eco-Driving principles. A new concept labeled ‘Eco-Hauling’, which extends the Eco-Driving concept to earthmoving, is proposed. A case study of a road project has been conducted and used to demonstrate the new concept. Discrete-event simulation is used to support the data analysis as it enables modeling of the dynamic interactions between equipment and activities of multiple different construction scenarios. The presented findings show that a combination of decisions taken from the proposed Eco-Hauling concept can enable earthmoving contractors to substantially reduce carbon dioxide emissions and costs while maintaining productivity. This study has implications for the general advancement of Eco-Driving theory, as well as for project management as it sets out a viable approach for reducing greenhouse gas emissions in construction projects.

  • 4.
    Sandberg, Marcus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mukkavaara, Jani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Shadram, Farshid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Multidisciplinary Optimization of Life-Cycle Energy and Cost Using a BIM-Based Master Model2019Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 11, nr 1, artikel-id 286Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Virtual design tools and methods can aid in creating decision bases, but it is a challenge to balance all the trade-offs between different disciplines in building design. Optimization methods are at hand, but the question is how to connect and coordinate the updating of the domain models of each discipline and centralize the product definition into one source instead of having several unconnected product definitions. Building information modelling (BIM) features the idea of centralizing the product definition to a BIM-model and creating interoperability between models from different domains and previous research reports on different applications in a number of fields within construction. Recent research features BIM-based optimization, but there is still a question of knowing how to design a BIM-based process using neutral file formats to enable multidisciplinary optimization of life-cycle energy and cost. This paper proposes a framework for neutral BIM-based multidisciplinary optimization. The framework consists of (1) a centralized master model, from which different discipline-specific domain models are generated and evaluated; and (2) an optimization algorithm controlling the optimization loop. Based on the proposed framework, a prototype was developed and used in a case study of a Swedish multifamily residential building to test the framework’s applicability in generating and optimizing multiple models based on the BIM-model. The prototype was developed to enhance the building’s sustainability performance by optimizing the trade-off between the building’s life-cycle energy (LCE) and life-cycle cost (LCC) when choosing material for the envelope. The results of the case study demonstrated the applicability of the framework and prototype in optimizing the trade-off between conflicting objectives, such as LCE and LCC, during the design process.

  • 5.
    Feng, Kailun
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande. Department of Construction Management, Harbin Institute of Technology, Harbin, 150001, China.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Chen, Shiwei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. 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 study2018Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 11, artikel-id 3868Artikel i tidskrift (Refereegranskat)
    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.

  • 6.
    Jansson, Gustav
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Viklund, Emma
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Artistic and Engineering Design of Platform-Based Production Systems: A Study of Swedish Architectural Practice2018Ingår i: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 8, nr 2, artikel-id 34Artikel i tidskrift (Refereegranskat)
    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.

  • 7.
    Jassim, Hassanean S.H.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande. Department of Civil Engineering, College of Engineering, University of Babylon.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Assessing energy consumption and carbon dioxide emissions of off-highway trucks in earthwork operations: an artificial neural network model2018Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, s. 364-380Artikel i tidskrift (Refereegranskat)
    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.

  • 8.
    Sandberg, Karin
    et al.
    RISE - Research Institutes of Sweden, Byggteknik.
    Pousette, Anna
    RISE - Research Institutes of Sweden, Byggteknik.
    Norén, Joakim
    RISE - Research Institutes of Sweden, Byggteknik.
    Sandberg, Marcus
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mukkavaara, Jani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Hållbarhetsutvärdering av byggnader: Case Ripan i Kiruna2018Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Hållbarhet innefattar flera parametrar och dessa kan mätas och värderas på många olika sätt. Att väga ihop de olika delarna för att uppnå hållbarhet genom att minimera förbrukad energi för uppvärmning och energi för att producera material till bygget samt investeringskostnader för material och kostnader för uppvärmning är fokus i denna rapport. Detta vägs samman med miljöpåverkan. En inledande studie för hållbarhetsoptimering av en mindre byggnad är genomförd med målet är att utveckla en övergripande metod för att ge bredare beslutsunderlag vid nybyggnad.

    Beräkningar av inbyggd energi, driftsenergi, investerings- och uppvärmningskostnader har genomförts för ett planerat hus på Camp Ripan i Kiruna. I beräkningen av byggnaden inkluderades klimatskärm (ytterväggar, stomstabiliserande element och grund) för två olika stommar av trä (träregelstomme och KL-trä). För miljöberäkningarna användes främst indata från EPDer och resultatet redovisas i form av klimatpåverkan, CO2-ekvivalenter.

    Den utvecklade metoden ger potential för bättre ekologisk och ekonomisk hållbarhet genom ett optimerat val av byggnadsmaterial för byggnader. Optimeringsalgoritmen ger förslag på byggnadsmaterial med minst energiåtgång vid produktion, den sk inbyggda energin, samt vid uppvärmning under driftsfasen samt lägst kostnader. Miljöaspekten vägs också in i bedömningen för att få ett mer heltäckande beslutsunderlag för beställare och projektörer. Metoden är tänkt att i fortsatta studier vidareutvecklas för användning på mer komplexa byggnader som till exempel flerbostadshus.

    Resultatet från Case Ripan visar att regelkonstruktionen har lägst inbyggd energi, driftsenergi, investeringskostnad samt kostnad för uppvärmning under driftsfasen. Även miljöpåverkan från regelkonstruktionen var låg.

  • 9.
    Jansson, Gustav
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mukkavaara, Jani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Interactive visualization for information flow in production chains: Case study industrialised house-building2018Ingår i: Proceedings of the 35th ISARC, Berlin, Germany, IAARC Publications , 2018, Vol. 35, s. 382-388Konferensbidrag (Refereegranskat)
    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.

  • 10.
    Jassim, Hassanean
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande. Babylon University.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Quantification of Energy Consumption and Carbon Dioxide Emissions During Excavator Operations2018Ingår i: Advanced Computing Strategies for Engineering: 25th EG-ICE International Workshop 2018, Lausanne, Switzerland, June 10-13, 2018, Proceedings, Part I, Cham, 2018, s. 431-453Konferensbidrag (Refereegranskat)
    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

  • 11.
    Mukkavaara, Jani
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Jansson, Gustav
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Structuring information from BIM: A glance at bills of materials2018Ingår i: Proceedings of the 35th ISARC, Berlin, Germany, IAARC Publications , 2018, Vol. 35, s. 362-368Konferensbidrag (Refereegranskat)
    Abstract [en]

    Industrialized house-builders are moving towards an enhanced production where management of information along the value chain is critical in order to deliver housing projects on time and with the desired quality. Today digital tools and systems are used in both design and production to produce, deliver and instruct actors throughout the phases of aproject. However, the information usually exists in different islands and manual transfers are required tokeep the flow of information between IT-systems and individuals continuous. A key to improving the ability for the members in different stages of a project to work with the same information is to facilitate different views. One of the building blocks for creating bridges between the islands of information is to introduce bills of materials which can be used to organize information for different purposes. Uniting the use of building information modeling (BIM) withbills of materials (BOM) is therefore our focus in this paper. This is done in the context of industrialized house-building and the facets which it brings to the subject. The aim of this paper is to present an early endeavor into a BOM based approach for structuring information from BIM models. A demonstration tool was developed, and together with application in a case project from an industrialized house-builder, the generation of BOMs from BIM data is illustrated and discussed. The findings illustrates that we can apply different structures to the information located in our BIM models and that we can produce a BOM perspective on our products. Also, it is highlighted that we still need further studies to better understand how application of BOMs in the context of industrialized house-building is realized.

  • 12.
    Yang, Bin
    et al.
    School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Wang, Faming
    Institute of Textiles and Clothing, The Hong Kong Polytechnic University.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Thermal comfort in primary school classrooms: A case study under subarctic climate area of Sweden2018Ingår i: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 135, s. 237-245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Limited studies were focused on primary school buildings especially under subarctic climate. Thermal comfort of children was assumed to be similar as that of adults, which may cause inaccuracy. To fill data blank and enrich global database, a field study was performed from late fall 2016 to early spring 2017 covering whole heating period in north part of Sweden. Indoor CO2 concentration was continuously monitored to evaluate indoor ventilation. Thermal comfort related parameters were continuously measured and predicted mean vote (PMV) was calculated. Subjective questionnaire surveys were performed every week except holidays. Subjective thermal sensation value (TSV) was always higher than objective PMV, which reflected thermal adaptation. The thermal adaptation became not obvious in middle and late winter because of long term exposure to heating environments. Heating system should be intensified gradually in early heating period, operated based on actual outdoor climate instead of experience in middle and late heating periods, extended under part load operation in early spring if necessary. The new 13─point TSV scale was pointed out by other researchers and tested inthis study, which can explore tiny TSV deviations from thermally neutral status and reflect more accurate thermal sensations.

  • 13.
    Shadram, Farshid
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mukkavaara, Jani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Schade, Jutta
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Sandberg, Marcus
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    A BIM-Based Method for Analyzing the Trade-Off between Embodied and Operational Energy2017Ingår i: ICCREM 2016: BIM Application and Offsite Construction - Proceedings of the 2016 International Conference on Construction and Real Estate Management 2016 / [ed] Wang Y.,Al-Hussein M.,Shen G.Q.P.,Zhu Y., Reston, VA: American Society of Civil Engineers (ASCE), 2017, s. 59--70Konferensbidrag (Refereegranskat)
    Abstract [en]

    Research indicates that the operational energy and the embodied energy caused by production of building materials off-site (i.e., "cradle-to-gate" embodied energy) contribute to the major part of a building's total energy use, with roughly equal proportions. In addition, it has been reported that there is a trade-off between embodied-and operational energy which is mainly due to the use of additional materials with higher embodied energy and utilization of new appliances for construction of the building (or building of interest). Hence, application of sustainable strategies in early stages of the design phase, which enables evaluation of different design scenarios in terms of materials and systems, can provide a great scope to launch an optimization in the trade-off between embodied-versus operational energy. With respect to early stages of the design phase, Building information modeling (BIM) has become an applicable platform where its recent developments can provide interoperability with energy performance simulation (EPS) tools that enable assessment of the operational energy. However, existing BIM software generally lacks interoperability with conventional life cycle assessment (LCA) tools that are the main means for assessment of the embodied energy. Consequently, embodied energy assessment is often performed when the design has either been accomplished or developed to a relatively detailed level where there is less scope to investigate different design decisions for analyzing the trade-off between embodied-and operational energy. To overcome this obstacle, this paper presents a BIM-based method which strives to reduce the building's life cycle energy (LCE) use by accounting the trade-off between embodied-and operational energy at early stages of the design phase. The method is then exemplified by using an energy-efficient building case, demonstrating the applicability of the method in reducing the building's total energy use and also highlighting the areas where further development is required to address in future research

  • 14.
    Krantz, Jan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Johansson, Tim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Analysis of alternative road construction staging approaches to reduce carbon dioxide emissions2017Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 143, s. 980-988Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite many studies focusing on assessing energy use and carbon dioxide emissions in road projects, limited attention has been given to practical methods for mitigating environmental impacts at the project planning stage. Our study addresses this issue by proposing a model incorporating a step-by-step guide for calculating carbon dioxide emissions in the project. This model is practically applied to a road construction project where two major supply chain alternatives are evaluated and compared. The findings suggest that major reductions of carbon dioxide emissions can be achieved by (1) identifying and comparing a set of realistic project alternatives, and (2) conducting this at an early stage of the project planning process so that favorable alternatives can be implemented during construction.

  • 15.
    Shadram, Farshid
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Assessment of the Energy Use and CO2 Emissions from a Construction Site: An Integrated BIM-DES-LCA Framework2017Ingår i: ICCREM 2016: BIM Application and Offsite Construction - Proceedings of the 2016 International Conference on Construction and Real Estate Management 2016 / [ed] Wang Y.,Al-Hussein M.,Shen G.Q.P.,Zhu Y., Reston, VA: American Society of Civil Engineers (ASCE), 2017, s. 518-526Konferensbidrag (Refereegranskat)
    Abstract [en]

    The building sector contributes significantly to the energy use and related greenhouse gas (GHG) emissions. Prior research has mainly focused on the impacts associated with material selection and building operation, thereby the embodied impact of the construction phase has got limited attention. The construction phase usually suffers from an inherent uncertainty in which construction operations, activities, and resources interact with each other in a complex manner. The discrete event simulation (DES) has been recognized to be a consistent simulation approach to capture these uncertainties and interactions. DES can also complement conventional life cycle assessment (LCA) tools, used for sustainable design and environmental strategies. However, the major challenge has been the implementation of the DES into practice which needs significant effort and work in order to create a realistic model of the construction process. To overcome this obstacle, this paper proposes a framework that integrates building information modeling (BIM), DES, and LCA in order to support the environmental evaluation and also facilitate implementation of the DES model by utilizing the data-rich BIM. Finally, the practical application of the proposed BIM-DES-LCA framework is demonstrated in a preliminary prototype and the areas where further development is required have been highlighted to address in future research

  • 16.
    Johansson, Tim
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mangold, Mikael
    Research Institutes of Sweden, City Development.
    Development of an energy atlas for renovation of the multifamily building stock in Sweden2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 203, s. 723-736Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many studies have highlighted the importance of retrofitting to mitigate the energy use of building stocks. An important step in the development of renovation strategy and energy conservation advising is to gather information of the energy performance of the existing buildings. However, renovation strategies must also consider the socio-economic challenges associated with the cost of energy retrofitting. This paper describes the development of an energy atlas of the multifamily building stock in Sweden for visualizing and analyzing energy use and renovation needs. The atlas has been developed using Extract Transform and Load technology (ETL) to aggregate information on the energy performance, building ownership, renovation status, and socio-economic status of inhabitants from various data sources. The atlas can visualize the energy use and renovation status of multifamily buildings in 2D maps and 3D models, displaying data for either individual buildings or aggregated data on spatial scales ranging from 250 × 250 m squares through district and municipality to county areas. A demonstration of its use on national and city scales indicates that energy retrofits of multifamily buildings reaching a service life of 50 years can reduce the energy use of the existing building stock by up to 50% relative to 1990. However, costs associated with renovation and energy retrofits of multifamily buildings can be problematic, especially in economically weak suburbs. A good understanding of past and future renovation needs and socio-economic consequences is important in the development of a sustainable national renovation strategy.

  • 17.
    Jassim, Hassanean
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Predicting energy consumption and CO2 emissions of excavators in earthwork operations: An artificial neural network model2017Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, nr 7, artikel-id 1257Artikel i tidskrift (Refereegranskat)
    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.

  • 18.
    Lidelöw, Helena
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    The Structure and Predefinition of the Industrialized Construction Value Chain2017Ingår i: ICCREM 2016: BIM Application and Offsite Construction - Proceedings of the 2016 International Conference on Construction and Real Estate Management 2016 / [ed] Wang Y.,Al-Hussein M.,Shen G.Q.P.,Zhu Y., Reston, VA: American Society of Civil Engineers (ASCE), 2017, s. 117-125Konferensbidrag (Refereegranskat)
    Abstract [en]

    Industrialized construction means predefinition of products and processes. The level of predefinition is balanced against the level of needed flexibility to create the desired customer value. There is a range from no predefinition up to complete predefinition. This pattern can be repeated in different dimensions defining several decoupling points in the value chain. The aim of this paper is to map different situations of predefinition in design, supply, and production dimensions in order to understand the structure of industrialized construction value chains. A multiple case study was organized using secondary data collection from earlier work of the authors originally collected through interviews with key actors in industrialized construction companies in Sweden. The results show that long-term supplier agreements and cooperations are important to sustain industrialization of construction. A high degree of predefinition in design is a prerequisite to succeed in construction industrialization. However, there is no coupling between a high degree of predefinition in design and a high degree of mechanization and automation in production

  • 19.
    Jassim, Hassanean
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Krantz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    A Cradle-to-Gate Framework for Optimizing Material Production in Road Construction2016Ingår 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, nr 19, s. 758-764Konferensbidrag (Refereegranskat)
    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.

  • 20.
    Jassim, Hassanean S. H.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    A Practical Method for Assessing the Energy Consumption and CO2 Emissions of Mass Haulers2016Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, nr 10, artikel-id 802Artikel i tidskrift (Refereegranskat)
    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.

  • 21.
    Shadram, Farshid
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Johansson, Tim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Schade, Jutta
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    An integrated BIM-based framework for minimizing embodied energy during building design2016Ingår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 128, s. 592-604Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Assessment of the embodied energy associated with the production and transportation of materials during the design phase of building provides great potential to profoundly affect the building’s energy use and sustainability performance. While Building Information Modeling (BIM) gives opportunities to incorporate sustainability performance indicators in the building design process, it lacks interoperability with the conventional Life Cycle Assessment (LCA) tools used to analyse the environmental footprints of materials in building design. Additionally, many LCA tools use databases based on industry-average values and thus cannot account for differences in the embodied impacts of specific materials from individual suppliers. To address these issues, this paper presents a framework that supports design decisions and enables assessment of the embodied energy associated with building materials supply chain based on suppliers’ Environmental Product Declarations (EPDs). The framework also integrates Extract Transform Load (ETL) technology into the BIM to ensure BIM-LCA interoperability, enabling an automated or semi-automated assessment process. The applicability of the framework is tested by developing a prototype and using it in a case study, which shows that a building’s energy use and carbon footprint can be significantly reduced during the design phase by accounting the impact of individual material in the supply chain.

  • 22.
    Sandberg, Marcus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Gerth, Robert
    Design Evolution Scandinavia AB.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Jansson, Gustav
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Mukkavaara, Jani
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Design automation in construction: An overview2016Ingår i: Proceedings of the 33rd CIB W78 Conference 2016, Oct. 31st – Nov. 2nd 2016, Brisbane, Australia, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    As the construction industry continues its digital journey the applications within design automation is growing, making development processes less time-demanding and more organized. Design automation applications can show design impact on e.g. cost, equipment availability, staff capabilities and buildability. It can also facilitate reuse of successful solutions instead of reinventing the wheel for every project. Thanks to automation it becomes easier to generate several solutions and trying different what-if-conditions. The field has many different approaches but an overview for construction where the connections between the different approaches are indicated is needed. The purpose of this paper is to describe our view of how the design automation fields of building information modelling, master models,  nowledge-based engineering, configuration, modularization, platforms and simulation are  onnected and to provide input to the design automation discussion in construction. Each of  hese areas are introduced and then they are analyzed in relation to each other and presented as an overview. These results will serve as a base for future studies.

  • 23.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Krantz, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Discrete Event Simulation Analysis of Product and Process Platforms: A Bridge Construction Case Study2016Ingår i: Journal of construction engineering and management, ISSN 0733-9364, E-ISSN 1943-7862, Vol. 142, nr 4, artikel-id 4015097Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Product and process platforms have been promoted as possible enablers of increased productivity in civil engineering. However, such platforms are traditionally applied in mass manufacturing industries where production assets are employed in continuous production of uniform products, which strongly facilitates continuous improvement. The discontinuous nature of project-based production in civil engineering restricts such possibilities. Thus, if platforms are implemented there is a need for methods capable of evaluating the performance of integrated product and production process configurations in specific projects. A possibility, explored in this paper, is to use database-driven simulation. As a case study, a configurable simulation model, based on standardized process patterns and values stored in a platform, has been developed of the production for a bridge concept. The presented results provide evidence that database-driven simulation can support efficient platform evaluation and development by integrating product and process information, even in discontinuous, project-based industrial sectors. The results specifically demonstrate that this approach can be used to evaluate effects of different configurations of construction methods on working time requirements without time-consuming updates of models.

  • 24.
    Johansson, Tim
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Energy performance certificates and 3-dimensional city models as a means to reach national targets: A case study of the city of Kiruna2016Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 116, s. 42-57Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Enhanced dissemination of information regarding energy saving and climate change targeted toward property owners is considered to be an important strategy in order to reach the Swedish national target of energy efficiency in the building sector by 2050. Here the municipality energy advisors and the national register for energy performance certificates can facilitate the mitigation of energy use in the building stock. So far few studies have focused on the practical road map to the national target of energy use on the city/district level and to the communication aspects with stakeholders in the creation of energy city models.In this paper a city energy model is developed based on the requests and need for visualization from a group of energy advisors. Six different scenarios are studied in order to analyze the possibility of reaching the energy targets specified by the government in the town of Kiruna. The results show that: (1) it is possible to automatically create city energy models using extract, transform and load tools based on spatial and non-spatial data from national registers and databases; (2) city energy models improve the understanding of energy use in buildings and can therefore be a valuable tool for energy advisors, real estate companies and urban planners. The case study of Kiruna showed that the proposed energy saving measures in the energy performance certificates need to be implemented and new buildings in the urban transformation must be of high energy standard in order to reach the national target in Kiruna.

  • 25.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Eriksson, Per-Erik
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Innovation och Design.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Swedish Transport Administration Luleå.
    Erratum for “Leadership in Civil Engineering: Effects of Project Managers’ Leadership Styles on Project Performance” by Johan Larsson, Per Erik Eriksson, Thomas Olofsson, and Peter Simonsson2016Ingår i: Journal of Management in Engineering, ISSN 0742-597X, E-ISSN 1943-5479, Vol. 32, nr 4, artikel-id 8216001Artikel i tidskrift (Refereegranskat)
  • 26.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Jansson, Gustav
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Simonsson, Peter
    Trafikverket.
    Increased innovation through change in early design procedures2016Ingår i: 19th IABSE Congress Strockholm 21-23 September 2016: Challenges in Design and Construction of an Innovative ans Sustainable Built Environment / [ed] Lennart Elfgren, Johan Jonsson, Mats Karlsson, Lahja Rydberg-Forssbeck and Britt Sigfrid, CH - 8093 Zürich, Switzerland, 2016, s. 685-692Konferensbidrag (Refereegranskat)
    Abstract [en]

    Increasing industrial productivity and innovation is essential to meet needs to reduce lead times and costs. However, diffusion of systemic innovations in project-based industries (PBIs), such as the infrastructure sector, has proven difficult. The Swedish Transport Administration (STA) has unique opportunity to influence the degree of innovation in the sector, due to its strong position as the largest public client of infrastructure in Sweden. Therefore, the aims of an ongoing study reported here are to identify and evaluate challenges and requirements affecting the diffusion of innovation related to this key client. This is being done by examining relevant aspects of construction infrastructure projects executed via the pre-defined design procedure currently applied by STA. The results reveal that the procedure hampers diffusion since certain activities must be performed early, is applied indiscriminately to all types of projects, and hinders inter-organizational collaboration.

  • 27.
    Olofsson, Thomas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Claeson-Jonsson, Christina
    NCC Sverige AB.
    Simonsson, Peter
    Swedish Transport Administration, Luleå.
    Mapping of resource consumption in transport infrastructure project: A case study of Bårhultsmotet2016Ingår i: 19th IABSE Congress Strockholm 21-23 September 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment, CH - 8093 Zürich, Switzerland, 2016, s. 573-579Konferensbidrag (Refereegranskat)
    Abstract [en]

    The purpose of the study is to 1) investigate the possibility to collect and present data of consumed human resources from all stakeholders over the project life cycle of transport infrastructure project; 2) discuss the use of such information with regard to the evaluation and suggestion for improvement of project performance. A well-defined engineering project, the interchange Bårhultsmotet consisting of two bridges over the route 40, was used as case study. A diagram presenting consumption of human resources over the project life cycle was constructed, starting at the initial project phase in the client organization and ending when the bridge was handed over for operation. The diagram raise a number of questions whether or not the time spent is value adding, especially between project phases considering the long lead times. The diagram also inspires to discussions of topics for further studies, for example the how to manage the gap (e.g. transfer/loss of information) between planning, design and construction phases in order to utilize the human resources more efficiently.

  • 28.
    Olofsson, Thomas
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Jensen, Patrik
    Design Evolution.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Larsson, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Product and Process Platforms in Transport Infrastructure Projects2016Ingår i: IABSE CONGRESS, STOCKHOLM, 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment / [ed] Lennart Elfgren, Johan Jonsson, Mats Karlsson, Lahja Rydberg-Forssbeck and Britt Sigfrid, CH - 8093 Zürich, Switzerland, 2016, s. 529-536Konferensbidrag (Refereegranskat)
    Abstract [en]

    Construction is traditionally a trade that produces unique, one-off products designed specifically according to the project requirements. However, recently developed flexible product and process platforms in industrialized house building based on the theory of mass customisation offer products that can be customized to a large extent with affordable costs. In this paper we present a framework for how a product and process platform can be developed and used in a traditional engineer-to-order design and construction of transport infrastructure products. The framework is exemplified in a case study, where a typical concrete bridge type is modularised and customized using a product configurator.  A database driven simulation model using process patterns and values stored in the platform, is then constructed to test the buildability of the bridge configuration. The results presented provide evidence that product and process platforms can support the design, and planning process of transport infrastructure projects, by integrating product and process information. The results specifically demonstrate how product configuration and database-driven simulation can be used to evaluate the effects of design alternatives and construction methods on performance measures such as productivity and environmental impact.

  • 29.
    Johansson, Tim
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Segerstedt, Eugenia
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriellt och hållbart byggande.
    Jakobsson, Mats
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Revealing Social Values by 3D City Visualization in City Transformations2016Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 8, nr 2, artikel-id 195Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Social sustainability is a widely used concept in urban planning research and practice. However, knowledge of spatial distributions of social values and aspects of social sustainability is required. Visualization of these distributions is also highly valuable, but challenging, and rarely attempted in sparsely populated urban environments in rural areas. This article presents a method that highlights social values in spatial models through 3D visualization, describes the methodology to generate the models, and discusses potential applications. The models were created using survey, building, infrastructure and demographic data for Gällivare, Sweden, a small city facing major transformation due to mining subsidence. It provides an example of how 3D models of important social sustainability indices can be designed to display citizens’ attitudes regarding their financial status, the built environment, social inclusion and welfare services. The models helped identify spatial variations in perceptions of the built environment that correlate (inter alia) with closeness to certain locations, gender and distances to public buildings. Potential uses of the model for supporting efforts by practitioners, researchers and citizens to visualize and understand social values in similar urban environments are discussed, together with ethical issues (particularly regarding degrees of anonymity) concerning its wider use for inclusive planning.

  • 30.
    Krantz, Jan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Shadram, Farshid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Larsson, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    A Model for Assessing Embodied Energy and GHG Emissions in Infrastructure Projects2015Ingår i: ICCREM 2015: Environment and the Sustainable Building : proceedings of the 2015 international conference on construction and real estate management : August 11-12, 2015 Luleå, Sweden / [ed] Yaowu Wang; Thomas Olofsson; Geoffrey Qiping Shen; Yong Bai, Reston, Va: American Society of Civil Engineers (ASCE), 2015, s. 1070-1077Konferensbidrag (Refereegranskat)
    Abstract [en]

    Construction and operation of buildings and infrastructure is a main contributor to emissions of greenhouse gases (GHG) in Sweden. The embodied energy of construction, meaning all the energy that is used until the completion of the construction project (see Figure 1), cause roughly 10 million tones of CO2 equivalent emissions each year which equals to the emissions from all cars in Sweden (IVA 2014). About 6 million tones of CO2 equivalent emissions are attributed to the embodied energy of roads, railroads and other civil works while the remaining 4 million tones are attributed to the embodied energy of buildings (IVA 2014). Although reducing energy use and associated GHG-emissions in road and railroad construction is prioritized by the Swedish Transport Administration (Trafikverket 2012), the GHG-emissions from such construction projects have increased in recent years (Boverket 2014). Many of the existing efforts to reduce energy use and associated GHG-emissions focus on individual phases of the life cycle and don’t take into consideration the effects at other stages during the whole life cycle of a project (Boverket 2011). A crucial step in the assessment of energy use and associated GHG-emissions is to clarify and categorize the different phases of a life cycle. Figure 1 shows a proposed categorization of life cycles phases and use of energy based on previous research (Davies et al. 2014). Buildings’ main use of energy happens during its operational phase from e.g. heating, lighting and use of electrical appliances (Sartori and Hestnes 2007). In infrastructure projects such as road construction the embodied energy is roughly equal to the operational energy for roads with lighting, or in fact considerably higher if the road lacks lighting (Stripple 2001).

  • 31.
    Shadram, Farshid
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Johansson, Tim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    An Integrated BIM-based framework for energy assessment of the building upstream flow2015Ingår i: ICCREM 2015: Environment and the Sustainable Building : proceedings of the 2015 international conference on construction and real estate management : August 11-12, 2015 Luleå, Sweden / [ed] Yaowu Wang; Thomas Olofsson; Geoffrey Qiping Shen; Yong Bai, Reston, Va: American Society of Civil Engineers (ASCE), 2015, s. 107-118Konferensbidrag (Refereegranskat)
    Abstract [en]

    The construction and operation of buildings account for a significant part of the energy use and greenhouse gas emissions. Most design approaches to reduce the use of energy are focusing on the operational phase of a building’s life. Consequently, the embodied energy from the upstream flow, including production of building material and components, transport and assembly on-site, is often disregarded in the development of energy-efficient buildings. The purpose of this research is to propose a method to facilitate the assessment of the embodied energy and carbon footprint during the design and planning stage from the production of building material and components including the transportation to site. The framework makes use of Environmental Product Declaration (EPD) and supply chain information stored in a relational database of building materials and components, Building Information Models (BIM) for the assessment of the embedded energy in the building. Further, the feature manipulation engine (FME) is used to track transportation distances and transportation times from Google Map (GM) for the assessment of embedded energy from supplier to the construction site. Finally, a prototype is developed to demonstrate the practical application of the framework and to observe possible limitations and barriers.

  • 32.
    Krantz, Jan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Larsson, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Assessing Embodied Energy and Greenhouse Gas Emissions in Infrastructure Projects2015Ingår i: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 5, nr 4, s. 1156-1170Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Greenhouse gas (GHG) emissions from construction processes are a serious concern globally. Of the several approaches taken to assess emissions, Life Cycle Assessment (LCA) based methods do not just take into account the construction phase, but consider all phases of the life cycle of the construction. However, many current LCA approaches make general assumptions regarding location and effects, which do not do justice to the inherent dynamics of normal construction projects. This study presents a model to assess the embodied energy and associated GHG emissions, which is specifically adapted to address the dynamics of infrastructure construction projects. The use of the model is demonstrated on the superstructure of a prefabricated bridge. The findings indicate that Building Information Models/Modeling (BIM) and Discrete Event Simulation (DES) can be used to efficiently generate project-specific data, which is needed for estimating the embodied energy and associated GHG emissions in construction settings. This study has implications for the advancement of LCA-based methods (as well as project management) as a way of assessing embodied energy and associated GHG emissions related to construction.

  • 33. Wang, Yaowu
    et al.
    Olofsson, ThomasShen, Geoffrey QipingBai, Yong
    ICCREM 2015: Environment and the Sustainable Building : proceedings of the 2015 international conference on construction and real estate management : August 11-12, 2015 Luleå, Sweden2015Samlingsverk (redaktörskap) (Refereegranskat)
  • 34.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Eriksson, Per-Erik
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Innovation och Design.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Swedish Transport Administration Luleå.
    Leadership in Civil Engineering: Effects of Project Managers’ Leadership Styles on Project Performance2015Ingår i: Journal of Management in Engineering, ISSN 0742-597X, E-ISSN 1943-5479, Vol. 31, nr 6, artikel-id 4015011Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Successful completion of a construction project requires the ability to coordinate activities of numerous individuals participating in tasks that often have high levels of complexity and uncertainty. Thus, the project manager plays crucial roles, often setting the ground rules and fostering a collective approach that strongly influence project performance. However, there are uncertainties regarding various aspects of project managers’ influence, particularly related to their leadership style. Thus, the research reported in this paper explores the degrees to which leadership styles affect project outcome and specific leadership styles are appropriate in specific types of situations. The analysis is based on a questionnaire survey of views of 162 project managers employed by the largest public infrastructure client in Sweden. The results indicate that project performance (in terms of cost, time, and quality) is affected by leadership, suggesting that the project manager’s leadership style is a significant project success factor. Further, the results show that certain styles are appropriate in different situations, highlighting the importance of a contingency perspective

  • 35.
    Wang, Yaowu
    et al.
    Harbin Institute of Technology.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Preface2015Ingår i: ICCREM 2015: Environment and the Sustainable Building : proceedings of the 2015 international conference on construction and real estate management : August 11-12, 2015 Luleå, Sweden / [ed] Yaowu Wang; Thomas Olofsson; Geoffrey Qiping Shen; Yong Bai, Reston, Va: American Society of Civil Engineers (ASCE), 2015, s. iii-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The construction and operation of buildings account for a significant part of the energy use and greenhouse gas emissions. Most design approaches to reduce the use of energy are focusing on the operational phase of a building’s life. Consequently, the embodied energy from the upstream flow, including production of building material and components, transport and assembly on-site, is often disregarded in the development of energy-efficient buildings. The purpose of this research is to propose a method to facilitate the assessment of the embodied energy and carbon footprint during the design and planning stage from the production of building material and components including the transportation to site. The framework makes use of Environmental Product Declaration (EPD) and supply chain information stored in a relational database of building materials and components, Building Information Models (BIM) for the assessment of the embedded energy in the building. Further, the feature manipulation engine (FME) is used to track transportation distances and transportation times from Google Map (GM) for the assessment of embedded energy from supplier to the construction site. Finally, a prototype is developed to demonstrate the practical application of the framework and to observe possible limitations and barriers.

  • 36.
    Jensen, Patrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lidelöw, Helena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Product Configuration in Construction2015Ingår i: International Journal of Mass Customisation, ISSN 1742-4208, Vol. 5, nr 1, s. 73-92Artikel i tidskrift (Refereegranskat)
    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.

  • 37.
    Jansson, Gustav
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lundkvist, Robert
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    The role of experience feedback channels in the continuous development of house-building platforms2015Ingår i: Construction Innovation, ISSN 1471-4175, E-ISSN 1477-0857, Vol. 15, nr 2, s. 236-255Artikel i tidskrift (Refereegranskat)
    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

  • 38.
    Johansson, Tim
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    A Stakeholder Planning Support System for District Heating Systems2014Ingår i: Computing in civil and building engineering: proceedings of the 2014 International Conference on Computing in Civil and Building Engineering : June 23-25, 2014, Orlando, Florida / [ed] Raymond Issa; Ian Flood, Reston, Va.: American Society of Civil Engineers (ASCE), 2014, s. 713-720Konferensbidrag (Refereegranskat)
    Abstract [en]

    Energy conservation measures are needed to prevent the world from moving in an unsustainable direction. Actions targeting the building sector are especially vital since it stands for a large share of the total energy use. The objective of this research is, therefore, to provide a framework for using visualization of aggregated energy use over time in a district heating network to stakeholders. This is fulfilled by integrating building information and energy data from a district heating supplier. The integration of building information and energy data makes it possible to identify high energy consumers through a performance visualization interface. Furthermore, the interface is connected to a collaboration hub which offers a communication opportunity between consumers, suppliers, energy advisors and urban planners. Additionally, a stakeholder management approach is proposed to support the energy advisor in managing and selecting the consumers to target with advice and actions. The visualization, collaboration and the stakeholder component of the proposed system creates a Planning Support System (PSS) by which the citizens, energy advisors and urban planners can monitor the use of energy and also suggest actions to decrease the energy use of buildings. The next step of this research will be to evaluate and test the PSS together with energy advisors of 20 municipalities in Sweden.

  • 39.
    Krantz, Jan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Johansson, Tim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    An Energy Model for Sustainable Decision-Making in Road Construction Projects2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Road construction operations often require considerable amounts of energy in the form of fossil fuels, thus generating considerable greenhouse gas (GHG) emissions. While fuel efficiency of the heavy construction equipment is extensively studied, limited attention is given to how the construction process can be planned in order to reduce energy use and GHG-emissions. In this paper a conceptual model is proposed for the assessment of energy use and GHG-emission in road construction projects. When applied to a case study the conceptual energy model is a useful tool to asses and evaluate project alternatives in the early planning stages of road construction projects. As a result both the energy use and GHG-emissions in road construction projects can be reduced.

  • 40.
    Shadram, Farshid
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Sandberg, Marcus
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Schade, Jutta
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    BIM-based environmental assessment in the building design process2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Today, climate change is an issue of great concern. In addition, the building sector is considered to be one of the major energy users causing considerable amount of greenhouse gas emissions. Although, energy-efficient buildings are built today that use low amount of energy during operation, the embedded energy from construction and production of building material can still be relatively high. This paper focuses on the application of Building Information Modeling (BIM) using Environmental Product Declaration (EPD) to assess the environmental impacts from building materials and production to enable the designers to make environmentally friendlier decisions. Toward this approach, we propose a model which is examined in a case study of a roof structure on a commercial building which was constructed by off-site prefabricated roof-elements. As a result, the feasibility of the proposed model is appreciated in the assessment of the carbon footprint and embodied energy of the building materials and components. The proposed model needs to be further developed regarding the specification of the materials and components to make the information exchange between the BIM model and EPD in the environmental assessment of the building design more practicable.

  • 41.
    Lu, Weizhuo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Building information modeling and discrete event simulation: towards an integrated framework2014Ingår i: Automation in Construction, ISSN 0926-5805, E-ISSN 1872-7891, Vol. 44, s. 73-83Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The development of a realistic Discrete Event Simulation (DES) model needs the complete specification of the interdependencies between activities and resources. Also, the maintenance of an existing DES model is challenging especially when changes in the logical relationships between activities, resource allocation and design need to be considered. The process of development and maintenance is time-consuming, error-prone and it restricts the application of DES within the construction industry. In this research, a Building Information Modeling (BIM) and DES framework is proposed to enable the implementation and integration of DES in the planning and follow-up of construction activities. The framework consists of: (1) A building information modeling process that exports material quantity take-offs, schedules and required resources to a relational database and (2) An intelligent simulation engine that automatically reads information from the database at the start of each simulation run. This implies that changes in the building information modeling process, such as design modification, different resource allocations and alternative construction methods can be explored without manually checking and re-formalizing the simulation model. A preliminary prototype has been developed using the proposed BIM-DES framework. The initial results show that the proposed BIM-DES framework reinforces both elements by providing valuable additional information. BIM provides the product and process information to DES, facilitating the building and maintenance of the DES model; the DES model evaluates the construction performances and provides valuable feedback to the BIM process for decision support.

  • 42. Wikberg, Fredrik
    et al.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Ekholm, Anders
    Department of Construction Sciences, Design Methodology Division, Lund University.
    Design configuration with architectural objects: linking customer requirements with system capabilities in industrialized house-building platforms2014Ingår i: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 32, nr 1-2, s. 196-207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There are two main routes for customers of industrialized house building to follow: either rigid platforms offering preconfigured products, often called ‘type houses’, or more flexible platforms open to customization. The problem in customization is to link customer requirements with system opportunities. In axiomatic design processes, this problem is understood as the transformation of customer requirements in the architectural view into design parameters that are supported by the system. A new method is proposed that allows requirements and constraints of an industrialized building platform to be handled fully in the architectural view through configuration with so-called architectural objects. It is based upon established theories and complies with the rationale of separating platform development from product customization. An experimental study, using standard building information modelling software, shows that a hierarchical structure of architectural objects can support both the development, as well as the configuration process, of the platform. Modularization in the architectural view is believed to be an important first step to capturing user requirements in the development of platforms for a specific market segment. It is also anticipated that if these requirements can be conceptualized as architectural objects the capabilities in different configurator solutions can be made more transparent to the customer.

  • 43.
    Jensen, Patrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Smiding, Erik
    Tyréns AB.
    Gerth, Robert
    Tyréns AB.
    Developing products in product platforms in the AEC industry2014Ingår i: Computing in civil and building engineering: proceedings of the 2014 International Conference on Computing in Civil and Building Engineering : June 23-25, 2014, Orlando, Florida / [ed] Raymond Issa; Ian Flood, Reston, VA: American Society of Civil Engineers (ASCE), 2014, s. 1062-1069Konferensbidrag (Refereegranskat)
    Abstract [en]

    A 5-step method for developing configurable "products in product" platforms to be used in an engineer-to-order (ETO) design process is proposed. The idea is based on the transformation of typical product architectures into modular design platforms where standard and variant modules are identified and developed. The platform modules can then be configured and combined using traditional design methods to meet the project-specific requirements in the design process. Based on 1193 project designs, several configurable "products in product" were identified and developed in a real case study using the proposed method.

  • 44.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Eriksson, Per-Erik
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Innovation och Design.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Swedish Transport Administration Luleå.
    Industrialized construction in the Swedish infrastructure sector: core elements and barriers2014Ingår i: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 32, nr 1-2, s. 83-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Improving productivity and innovation is a central challenge in all industries, but particularly in construction where improvements have been slow. To meet this challenge, a recent investigation into the actions of Swedish government clients has recognized needs to improve planning during project procurement phases, increase numbers of turnkey contracts and raise industrialization of the sector. In response, the Swedish Transportation Administration has launched a research and innovation programme to foster an industrial approach and identify ways to increase the standardization of products and processes. However, increasing industrialization has been difficult to achieve in the project-based construction industry except in the process-based housing sector. Further, there has been little research on the concept of industrialized infrastructure construction and barriers to its implementation. Opinions and attitudes of clients, consultants and contractors in the infrastructure sector were investigated in relation to the core elements of industrialized construction, and the barriers hindering its development. Opportunities and obstacles related to both product and process standardization for continuous improvements and the relationships between clients and contractors are revealed. Hence, the implementation of industrialized construction requires tightly focused governance at the outset of projects and profound changes to established attitudes, norms and regulations

  • 45.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Platform concepts in bridge construction2014Ingår i: Computing in civil and building engineering: proceedings of the 2014 International Conference on Computing in Civil and Building Engineering : June 23-25, 2014, Orlando, Florida / [ed] Raymond Issa; Ian Flood, Reston, VA: American Society of Civil Engineers (ASCE), 2014, s. 1473-1480Konferensbidrag (Refereegranskat)
    Abstract [en]

    Improving productivity and innovation is a central challenge in all industries, but particularly in construction where improvements have been slow. The Swedish Transportation Administration, the largest public client in Sweden, has launched a research and innovation program to increase productivity by foster an industrial approach and identify ways to increase the standardization of products and processes. The use of customizable platforms in bridge construction is in this paper explored as a tool for increasing the standardization. Especially the connection between the product and process platforms is exemplified using a developed bridge concept by a Swedish contractor. The development of modular platforms needs to consider which components and processes that can be specified (standardized) in advance and which that needs to be uniquely adapted to the specific project. Also, the encapsulation of knowledge in standardized design and construction modules in supporting platforms and configuration tools turn tacit personal know-how into formal explicit knowledge that can be managed and continuously improved by the construction company.

  • 46.
    Schade, Jutta
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Wallström, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lagerqvist, Ove
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    A comparative study of the design and construction process of energy efficient buildings in Germany and Sweden2013Ingår i: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 58, s. 28-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reducing the energy consumption of buildings is an important goal for the European Union. However, it is therefore of interest to investigate how different member states address these goals. Countries like Sweden and Germany have developed different strategies for energy conservation within the building sector. A longitudinal comparison between implemented energy conservation key policy instruments in Sweden and Germany and a survey regarding the management of energy requirements in the building process shows that:– No evidence is found that energy consumption is of great importance for producing competitive offers, either for Swedish or German clients.– The Swedish market-driven policy has not been as successful as the German regulation policy in decreasing the energy consumption of new buildings.– Building standards and regulations regarding energy performance affects how professionals are educated and the way energy requirements and demands are managed throughout the building process.In conclusion, the client's demand will govern the development of energy efficient buildings. Therefore, in order to use market-driven policies, the desired parameters must be of concern for the customer to influence the majority of building projects to be more energy efficient than is specified in national standards and regulations.

  • 47.
    Sandberg, Marcus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    A product development approach to developing modularized and parametric building systems2013Ingår i: CIB W78: 30th International Conference on Applications of IT in the AEC Industry, 2013Konferensbidrag (Refereegranskat)
  • 48.
    Erikshammar, Jarkko
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lu, Weizhuo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Stehn, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Discrete event simulation enhanced value stream mapping: an industrialized construction case study2013Ingår i: Lean Construction Journal, ISSN 1555-1369, E-ISSN 1555-1369, Vol. 10, s. 47-65Artikel i tidskrift (Refereegranskat)
    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.

  • 49.
    Jensen, Patrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Larsson, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Improving buildability with platforms and configurators2013Ingår i: Proceedings IGLC-21: Conference of the International Group for Lean Construction / [ed] Carlos T. Formoso; Patricia Tzortzopoulos, Fortaleza, Brazil, 2013, s. 771-780Konferensbidrag (Refereegranskat)
    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.

  • 50.
    Jensen, Patrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Johansson, Tim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Smiding, Erik
    Tyréns AB.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Product configuration of roundabouts2013Ingår i: Proceedings of the 30th CIB W78 International Conference, 2013, s. 1-10Konferensbidrag (Refereegranskat)
    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.

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