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  • 1.
    Björnfot, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Bildsten, Louise
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Erikshammar, Jarkko
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Haller, Martin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Lessons learned from successful value stream mapping (VSM)2011Inngår i: Proceedings of IGLC-19: 19th Conference of the International Group for Lean Construction / [ed] John Rooke; Dave Bhargav, Lima: Fondo Ed. Pontificia Universidad Católica del Peru , 2011, s. 163-173Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    To improve, it’s crucial to see! Vital characteristics of Lean are visualisation and transparency, i.e. allowing everyone to see all what occurs in production. A common tool for this purpose is Value Stream Mapping (VSM). Due to varying flows, performing a successful VSM in construction confers additional challenges. In this paper, lessons learned from successful VSM studies in construction are provided.Three VSM case studies were performed at different companies ranging from patio door manufacturing to kitchen cabinet assembly. Lessons learned can be structured into three phases; preparing the VSM (selecting “value stream leaders” and VSM team, clarifying values, etc.), performing the VSM (use of mapping tools, approximation of key indicators, waste identification, etc.), and following-up the VSM (Plan-Do-Check-Act, evaluating customer values, etc.).For the involved companies, the lessons learned imply the start of a “Lean journey” even though the involved companies found it difficult to relate VSM improvements to business strategies. Consequently, there are opportunities to further improve the application of VSM. However, it’s important to remember that VSM is about the straight-forward visualisation of flows and that these flows are made transparent for the whole organisation.

  • 2.
    Björnfot, Anders
    et al.
    Faculty of Technology, Economy and Management, Gjøvik University College.
    Johnsson, Helena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    'Find-think-write-publish': Lean thinking in scientific paper writing2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Construction research supports long-term development of the construction industry and the society. Thus it is important to evaluate research against existing knowledge and to constantly develop new knowledge. The main mechanism for doing so is publishing scientific papers. In Sweden, praxis has developed that a Ph.D. consists of a handful of scientific papers. The average time period for a Ph.D. is five years after which the funding situation changes drastically. Previously, the duration of Ph.D. studies at Luleå University of Technology, Sweden often exceeded the planned five years, disrupting the flow of Ph.D. examinations. To increase awareness and interest in paper writing, a method was sought to visualise and manage the writing process. This paper investigates how an Oobeya room can be implemented in construction research to support paper writing. Experiences of working with the Oobeya room in three separate research divisions prove that it is possible and fruitful to better manage knowledge in academic institutions. Even though research is creative, it can be properly managed without hampering scientific freedom. Evidence from managing scientific paper writing using the Oobeya room shows that proper management of research will actually create better research that is more publishable with shorter lead times!.

  • 3.
    Emborg, Mats
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Jonasson, Jan-Erik
    Nilsson, Martin
    Utsi, Sofia
    Simonsson, Peter
    Designing robust SCC for industrial construction with cast in place concrete2005Inngår i: Second North American Conference on the Design and Use of Self-Consolidating Concrete [and] Fourth International RILEM Symposium on Self-Compacting Concrete; [October 30 - November 2, 2005];Second North American Conference on the Design and Use of Self-Consolidating Concrete [and] Fourth International RILEM Symposium on Self-Compacting Concrete; [October 30 - November 2, 2005: [proceedings] / [ed] Surendra P. Shah, Hanley Wood, 2005, s. 1251-1257Konferansepaper (Fagfellevurdert)
  • 4.
    Emborg, Mats
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Increasing the market share of SCC2010Inngår i: Concrete Plant International, ISSN 1437-9023, nr 3, s. 218-222Artikkel i tidsskrift (Annet vitenskapelig)
  • 5.
    Emborg, Mats
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Industrial casting of bridges with new production methods: the importance of a robust self compacting concrete2008Inngår i: Proceedings, Nordic Concrete Research, Bºalsta, Sweden: XXth Symposium on Nordic Concrete Research & Development ... The current proceedings contain 90 summaries of oral poster presentations] / [ed] Johan Silfwerbrand, Oslo: Norsk Betongforening , 2008, s. 170-171Konferansepaper (Fagfellevurdert)
  • 6.
    Emborg, Mats
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Industrial concrete construction for a better economy and working environment: possibilities and obstacles with self compacting concrete2008Inngår i: Nordic Concrete Research, ISSN 0800-6377, nr 2, s. 47-59Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The implementation of SCC together with new reinforcement and form techniques make it possible to increase the degree of industrialisation. It has been found in research at LTU that detailed planning and optimization of the building process, are essential utensils to successfully introduce such new techniques. However, also important is to address the technical issues hindering the marketing of SCC. Such issues are the robustness of the concrete and he surface quality. Thus, a discussion is given in the article on the optimization of robust SCC mixes and test results both from laboratory and building site as well as how criteria of SCC can be defined.

  • 7.
    Emborg, Mats
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Carlswärd, Jonas
    Nilsson, Martin
    Industrial casting of bridges combining new production methods materials: like a robust SCC, utilizing lean construction principle2007Inngår i: Proceedings of the 5th International RILEM Symposium on Self-Compacting Concrete: SCC2007 / [ed] G De Schutter; V Boel, Bagneux, France: Magnel Laboratory for Concrete Research, Ghent University , 2007, Vol. 1, s. 485-490Konferansepaper (Fagfellevurdert)
  • 8.
    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 configurators2013Inngår i: Proceedings IGLC-21: Conference of the International Group for Lean Construction / [ed] Carlos T. Formoso; Patricia Tzortzopoulos, Fortaleza, Brazil, 2013, s. 771-780Konferansepaper (Fagfellevurdert)
    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.

  • 9.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Barriers and drivers for increased use of off-site bridge construction in Sweden2012Inngår i: Association of Researchers in Construction Management (ARCOM): Proceedings of the 26th Annual Conference, 3-5 September, Edinburgh, Scotland / [ed] Simon Smith, Association of Researchers in Construction Management , 2012, Vol. 2, s. 751-761Konferansepaper (Fagfellevurdert)
    Abstract [en]

    There is great pressure to change the civil engineering industry in Sweden, which is said not to follow efficiency growth other manufacturing sectors are achieving. This increases a demand for innovative construction methods and a growing industrialised thinking for sustainable construction. By implementing off-site manufacturing (OSM) into bridge construction, client satisfaction can increase, bridges can be constructed faster using less resource, and more bridges for the same invested capital can be realised. A questionnaire survey and a workshop have been undertaken partly to identify benefits and drawbacks for OSM in bridge construction and partly to study if OSM satisfies the client better than on-site construction. The outcome shows that drivers of OSM meet client needs better than on-site construction alternatives. Time, cost and working environment are large drivers, correlating well with previous surveys undertaken. However, quality, as in other surveys tend to stand out as a driver, is a barrier in comparison with on-site construction. This opinion may be due to both the generally negative views for OSM bridges in Sweden and also due to previous bad experiences. Despite these negative views, results show that the hypothesis of OSM being a better alternative for satisfying the client is true. To increase its market share, barriers like reduced quality and not aesthetically pleasing must be overcome. OSM bridges are to date a rare feature in Sweden, but by display the drivers, it could become a common construction method in Sweden.

  • 10.
    Larsson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Decreasing complexity of the on-site construction process using prefabrication: a case study2012Inngår i: Proceedings IGLC-20: Conference of the International Group for Lean Construction, 18-20 July, San Diego, USA / [ed] Iris D Tommelein; Christine L Pasquire, 2012, s. 841-850Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Implementing prefabrication is by many seen as means to improve construction in terms of managing variability and productivity. However, regarding Swedish civil engineering works this has not been adequately documented to date. This case study uses Value Stream Mapping (VSM) to document the construction of a semi-prefabricated superstructure. The intention of the project is to investigate if the bridge construction process becomes less complex to manage and control when using prefabrication instead of traditional on-site construction.By relocating parts of traditional on-site construction to a factory, the time spent on site performing traditional work tasks such as constructing formwork, mounting and fixing of rebar and casting concrete, could be decreased. Nevertheless, mapping the process revealed shortcomings such as problems placing the prefabricated beams onto the on-site constructed plate structures and also that clear communication between actors tend to increase in importance when choosing prefabrication as construction method.Results from the VSM show that the semi-prefabricated superstructure, future state, became less complex compared to current state construction and also 75% quicker to construct on-site. By redesigning the bridge to eliminate some of the infant “diseases”, prefabrication will become more common in the future of small bridge construction in Sweden.

  • 11.
    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.
    Jensen, Patrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    BIM-based lean-agile supply chain for industrialized housing2011Inngår i: CONVR 2011: Proceedings of the 11th International Conference on Construction Applications of Virtual Reality / [ed] Hans-Joachim Bargstädt; Karin Ailland, Bauhaus-Universität Weimar , 2011, s. 262-270Konferansepaper (Fagfellevurdert)
    Abstract [en]

    From 1990 to 2002, approximately 74% single-family detached houses in Sweden are prefabricated by industrialized housing builders. To fulfill the benefits of industrialization, the design specifications have to be worked out from a list of predefined standardized components and elements. On the other hand, the requirements of client (diversity, cost and delivery time) make design specification process seems to be complex and paradoxical situation, which may lead to the ad-hoc design customization and slow response to potential client’s enquiry. This research therefore presents a BIM-based configuration design, in which lean-agile supply chain is used to balance and manage the trade-off between builders and clients, standardization and customization. Furthermore, integrating discrete event simulation (DES) with building information model (BIM) enables an enriched information model including cost and delivery time. The research argues that the industrialized housing is the systematic trade-off and balancing the values of all stakeholders and BIM-based lean-agile industrialized configuration design provides an effective trade-off platform.

  • 12.
    Rwamamara, Romuald
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Fitting steel reinforcement production methods to workers safety2009Konferansepaper (Annet vitenskapelig)
  • 13. Rwamamara, Romuald
    et al.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Health and safety in concrete casting processes2009Inngår i: Twenty-Fifth Annual Conference, 2009, September 7-9, Albert Hall, Nottingham / [ed] Andrew Dainty, Reading: Association of Researchers in Construction Management , 2009, Vol. 2, s. 1253-1262Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Construction injuries lead to human tragedies, disrupt construction processes and adversely affect the cost, productivity, and the reputation of the construction industry. Therefore, the use of ergonomic production methods to prevent this can have a significant human, social and financial impact. This paper presents a case study of comparative analyses of ergonomic situations for concrete workers performing concrete casting processes. Ergonomic risk assessment methods were used to assess the physical strain, hand-arm vibration and noise affects risks involved in concrete casting work tasks. The combination of technical and managerial factors results in a system where workers are as efficient and safe as possible during their work tasks, and thus, makes the construction work environment sustainable. The preliminary study presented in this paper concludes that the present ergonomic risks emanating from work methods used in the normally vibrated concrete (NVC) casting can be significantly reduced. With the use of self-compacting concrete (SCC) awkward work postures, hand-arm vibration and noise are eliminated. Thus musculoskeletal injuries can be reduced if not eliminated among concrete workers during their concrete casting work tasks.

  • 14.
    Rwamamara, Romuald
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Self-compacting concrete use for construction work environment sustainability2012Inngår i: Journal of Civil Engineering and Management, ISSN 1392-3730, E-ISSN 1822-3605, Vol. 18, nr 5, s. 724-734Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Many of those working on construction sites are exposed to demanding work loads; construction workers lift and carry heavy materials and work in awkward postures. Occupational injuries and accidents due to poor ergonomics are more common in the construction industry and many times lead to human tragedies, disrupt construction processes and adversely affect the cost, productivity, and the reputation of the construction industry. In Sweden, it is reported that concrete workers have the highest relative work-related musculoskeletal injury frequency. Therefore, the use of ergonomic production methods to prevent this can have a significant human, social and financial impact. Research introduced here presents a case study of comparative analyses of ergonomic situations for concrete workers performing concrete casting processes. Three different ergonomic risk assessment methods were used to assess the physical strain, hand-arm vibration and noise affects risks involved in concrete casting work tasks. The combination of technical and managerial factors results in a system where workers are as efficient and safe as possible during their work tasks, and thus, makes the construction work environment sustainable.The aim of our research is to find practical methods to evaluate and compare two different concrete casting methods from an ergonomic perspective. The focus is on the production of cast-in-place concrete bridge constructions where the traditional concrete casting method is compared with the SCC (Self-Compacting concrete) casting method. To be able to identify work-related musculoskeletal injury risks due to concrete casting work tasks, QEC (Quick Exposure Check for musculoskeletal risks), PLIBEL (Checklist for identification for Ergonomics Hazards) and ErgoSAM (Ergonomic production technology method) methods were used. Ergonomic risks analysis methods QEC, PLIBEL and ErgoSAM have all shown capabilities to evaluate construction work activities and thus determine whether a construction work activity constitutes a musculoskeletal risk to the worker or not before any ergonomic intervention is introduced.As a result the present ergonomic risks emanating from work methods used in the traditional concrete placing can be significantly reduced with the use of self-compacting concrete (SCC) that eliminates awkward work postures, noise and hand arm vibration, thereby reducing if not eliminating musculoskeletal injuries among concrete workers during their concrete casting work tasks.

  • 15.
    Rwamamara, Romuald
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Ojanen, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Advantages of industrialized methods used in small bridge construction2010Inngår i: Proceedings of IGLC-18: 18th Conference of the International Group for Lean Construction / [ed] Ken Walsh; Thais Alves, Haifa: Technion-Israel Institute of Technology , 2010, s. 569-579Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Evaluating to what extent industrialized production methods used during the steel reinforcement, formwork and concrete casting of small bridges are beneficial to the construction industry. The study evaluates the economical value of the construction of small bridges in terms of design and constructability from a production point of view. Moreover, the health and safety issues of the production processes are considered. The study method used is the internal documents study involved in the construction of the bridges. A comparison between data collected for previous studies on bridge construction projects and data collected from internal company documents will be performed. The study uses an economic analysis to evaluate alternative construction materials, assemblies, and bridge services with the objective to improve project planners or owners' decision making during the course of planning, designing and constructing a bridge. The use of bridge economic analysis to determine the most economically efficient choice among bridge design alternatives when it comes to steel reinforcement, formwork and concrete casting in regard to improved quality and working environment. The study discusses and offers recommendations for a cost effective bridge construction process which reduces waste in the production process and keeps the project schedule.

  • 16.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Buildability of concrete structures: processes, methods and material2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The causes for the slow development of the construction industry is often attributed the traditional ”peculiarities of construction“, including such factors as one-of-a-kind products, temporary organisation, and on-site production. However, signs of new thinking are becoming apparent in the construction industry in Sweden that emphasise change. Globalization and increased competition are factors for change. The possible future shortage of available qualified workers, demand for shorter construction times and calculated higher risks for projects are also catalysers for the implementation of new and alternative solutions. Still, new production methods and construction ideas are rarely introduced in construction projects, with low or no productivity increase of the industry as a result. Within the scope of this thesis work, the combination of creating buildability during the design phase and utilizing the philosophies of lean construction during the construction phase has been adapted to improve civil engineering concrete construction work. Several full scale projects have been studied and a questionnaire survey has been performed. In order to be able to introduce changes such as prefabricated reinforcement solutions, left concrete form systems and Self-Compacting Concrete (SCC) as a mean to increase productivity at site, there is a need to create projects that are buildable and able to be constructed, i.e. constructions that we know in advance are practically feasible and productive. All involved participants throughout the whole project are therefore responsible for creating buildability in the project. The case studies show that the potential increase in productivity can be vast. The introduction of prefabricated rebar sections, e.g. rebar carpets and rebar cages, decreases time spent on fixing reinforcement with up to 80%. The use of SCC potentially saves 65% on time spent during casting. Both methods improve the working environment substantially. However, the introduction of new methods also put demands on properly planned, communicated and managed construction operations on-site. Thus, the use of Buildability in the design can promote new solutions together with Lean Construction philosophies in management of these alternatives are suitable tools in changing the construction industry. Buildability deals with creating design for “ease of construction” whilst Lean construction focus on planning of a productive flow of work tasks and resources for the selected production methods. The combination of buildability in the “design for” part and lean construction philosophy in the “ease of construction” part within one of the most accepted definitions of buildability i.e. “the extent to which the design of a building facilitates ease of construction” will be able to encourage an increase in productivity at construction sites. This is possible if important factors are considered and utilised sufficiently. Some of these important factors highlighted in this thesis work are: • early project involvement of contractor, to increase construction knowledge during design, a result from the questionnaire survey; • design projects in 3D and create adequate virtual work instructions for workers to study prior to performing the work task, a result from full scale studies; • plan the construction work tasks and material supply thoroughly using lean tools, a result from full scale studies; • make sure adequate attention is spent on the working environment early in a project, this will result in workers feeling confident in a safe work environment, a result from full scale studies. The thesis corroborates the conclusion that, if these factors are considered and encouraged there is a potential for improvement of productivity at site, enhanced quality of finished structures as well as lowered costs for constructing structures in the future.

  • 17.
    Simonsson, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Industrial bridge construction with cast in place concrete: new production methods and lean construction philosophies2008Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The construction industry is associated with high costs, low productivity, a lack of quality and low profit margins. Too often the actual cost for a project exceeds the expected cost. Industrialization of the construction industry is said to be the key to success and its definition is often debated, but what is the meaning of industrialization? How should industrialization be realized in the construction industry? Who is responsible for the change within the industry and which benefits can be achieved by industrialization? These are some of the questions brought up during the course of the research project. The project has been financed by VINNOVA´s research consortium "Road/Bridge/Tunnel" and by Swedish Road Administration Business unit Production and Maintenance, Cementa and Betongindustri. SRA has also contributed with resources from the FUD Program (Research, Development, Demonstration). The project has so far comprised different forms of full scale studies, laboratory studies and theoretical work. In the beginning of the project, interviews were carried out with management of construction sites to lay a foundation for the time and cost apportionment of typical bridges, also to examine which common bottlenecks present in production and to examine how large part of the cast in place concrete the self compacting concrete (SCC) constitutes. The interview gave also an insight in how site management views the possibilities for change in construction today. To further find out the time and cost apportionment, ten bridge projects were examined. The results from this study were studied with regards to new production methods. Unit times for SCC were thus compared with unit times for traditionally vibrated concrete, unit times for rebar carpets were compared with unit times for traditionally clenched reinforcement, and also the effects of left formwork were studied. In these theoretical studies it was clear that great potential for changing today's construction business. To try to verify the theoretical results, mainly two full scale studies have been carried out. Te first was a replacement of an existing bridge on the European road No 4 outside Kalix in the northern parts of Sweden. The project was followed and managed by the research team in close collaboration with the client, contractor, designer and material suppliers. The study was comprehensive and started already in the design phase where the bridge was redesigned for new technical solutions aimed for production enhancement. Here prefabricated reinforcement cages to the foundation and SCC to the whole project were used. Also rebar carpets were used for the superstructure. The reinforcement in a typical bridge superstructure of today most often consists of approximately 80% longitudinal reinforcement and 20% shear force reinforcement. The project aimed at examining if it was technically feasible to use rebar carpets and if there were any economical benefits in using it. The aim was also to examine if it was economical to prefabricate reinforcement cages and transport them to the site for placement in comparison to traditionally fix reinforcement piece by piece. An additional objective was to examine the effect on the working environment imposed by the change in working methods. The other full scale project was concentrated on the use of SCC, but also the rebar carpets were examined to some extent. Here, the design phase was not followed by the researchers and no redesign for maximizing the use of carpets was performed. The aim for the project was above all to examine the economic conditions associated with the use of SCC, and to study the working environment in connection to the casting of SCC compared to traditionally vibrated concrete. The accomplished studies were successful. Especially at the bridge in Kalix, a detailed planning could be realized and Lean Construction philosophies were utilized, this proved to be an important factor for the success. Considerable savings in work efforts at site were realized (approximately 80% of the reinforcement fixing time and approximately 67% of the casting time). The total project time was decreased with approximately 20%. Also a lower total cost for the project was achieved. For the project in Nynäshamn the same effects were not realized since the ideas of new working methods and new planning systems came in to late. However, some positive experiences were gained considering the use of SCC and rebarcarpets. The much important working environment was followed up in the project with a special analytical method, ErgoSAM. Large differences in the workload were measured in a comparison between traditional reinforcement fixing and the handling of prefabricated reinforcement as well as when comparing traditionally vibrated concrete with SCC. The largest economic benefit from introducing SCC to a contractor in civil engineering projects is probably on the superstructure of a bridge, since the largest number of workers is needed during casting of traditional vibrated concrete and it is therefore associated with large casting costs. Hence, the number of workers needed for casting can be markedly reduced if SCC is introduced and proper planning has been carried out. However, controversially it is often easier to introduce SCC for foundations, columns or plate structures since these structural parts are less dominant in the construction and the "risk" related to using SCC is small. However, for these smaller less people demanding castings it is more difficult to achieve economical benefits in using SCC. The overall risk using SCC is that the product it is not robust enough, which might result in the concrete does not enclose the reinforcement satisfactory and rework is needed. Probably the largest benefit with using SCC is, as mentioned earlier, the improvement in working environment. Therefore, the economy of the Swedish construction industry and society can benefit significantly from using the right kind of working method during construction. Finally, it was concluded in the project that, to be able to utilize the "new" and improved production methods in a broader approach, it is of importance to apply Lean Construction philosophies at the planning and construction. Preferably a Lean Design Team should be established.

  • 18.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Björnfot, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Erikshammar, Jarkko
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    'Learning to see' the effects of improved workflow in civil engineering projects2012Inngår i: Lean Construction Journal, ISSN 1555-1369, E-ISSN 1555-1369, s. 35-48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Research Question/Hypothesis: Value Stream Mapping (VSM) can, independent of work repetition, improve the performance of civil engineering projects by allowing the site management to visualize the flows of materials, resources and information.Purpose: The purpose is to show how VSM can be used by on-site practitioners to see the day-to-day flow of work, to understand the effect of straight-forward improvements to workflow, and to see the effect of applying industrialized working methods.Research Method: Applicability of VSM to civil engineering is examined through the fixing of reinforcement in two bridge construction projects. A traditional bridge was used to map (current state) and improve (future state) workflow. The potential of modern production methods are then analyzed in a second bridge project (ideal state).Findings: Allowing the site management to visualize and to see workflow improves the work performance of the two studied bridges. Addition of easy to understand and calculable metrics for lead time, inventory level and manufacturing costs, emphasize the potential savings of reactive and proactive workflow measures (≈ 80-90 %).Limitations: The paper considers fixing of reinforcement in two bridge construction projects. Additionally, the so-called future state bridge was not actually constructed, i.e. the savings stated for the future state, even if reasonable, are an approximation.Implications: The framework to visualize current, future and ideal workflow provides a framework to extend the VSM methodology to civil engineering projects.Value for practitioners: To overcome the sub-optimized mindset in civil engineering that repeatedly leads to the same practice, the paper proposes a straightforward and easy to use framework to visualize and analyze effects of workflow improvements.

  • 19.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Carlswärd, Jonas
    Evaluation of a GPS support system for fleet management control2005Inngår i: Proceedings: 13th Conference of the International Group for Lean Construction / [ed] Russell Kenely, Sydney: International group for lean construction , 2005, s. 179-186Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Delivery precision and fleet optimisation are highly prioritised within the ready mix concrete industry. Introducing a Global Positioning System (GPS) for logistic steering and planning provides a tool to make improvements on these areas. Such a system is presently under evaluation at a ready mix concrete supplier in Stockholm, Sweden. The system consists of GPS receivers in the trucks that send relevant information via the General Packet Radio Service (GPRS) net to a server. A direct effect of implementing a GPS system is that the plants and the order central will be able to better control the whereabouts of the concrete trucks. As a result it will be possible to decrease the waste time at the plants. Another result is that the ratio of usage of concrete trucks will increase, leading to cut-downs in the truck fleet. It is further believed that the lead-time at work sites can be reduced as the delivery precision is improved. By eventually letting the contractor be a part of the system the possibilities for a good production planning at the work site will increase and the non-value adding activities will decrease due to reduced waiting time. The article presents findings from a pilot study in Stockholm, Sweden. An important ambition is to find out if the system gives the expected benefits. The customer value is evaluated through interviews and time measurements.

  • 20.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Increasing productivity through utilization of new construction techniques and lean construction philosophies in civil engineering projects2009Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 39, nr 1, s. 53-74Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The implementation of Self Compacting Concrete (SCC) together with two types of reinforcement and form techniques makes it possible to increase the degree of industrialization at construction sites markedly. To be able to realize this, Lean Construction principles prove to be important utensils during the planning and design phase. Also, the working environment is improved vastly when using SCC and different prefabricated reinforcement solutions. At the construction of the first full scale project "The Industrialized Concrete Bridge", which was built during 2006 in Sweden, the new techniques were applied. It was concluded that the working environment was improved by three fold, production time at site could be reduced with up to 20 % and that the number of workers could be reduced by virtually 25 %.

  • 21.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Increasing the use and performance of SCC in bridges2011Inngår i: Nordic Concrete Research: Proceedings of the XXI Nordic Concrete Research Symposium, Hämeenlinna, Finland 2011, Oslo: The Nordic Concrete Federation , 2011, s. 99-103Konferansepaper (Fagfellevurdert)
  • 22.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Industrialization in Swedish bridge engineering: a case study of lean construction2007Inngår i: Proceedings: International group for lean construction conference. IGLC 15, East Lansing: Michigan State University Press, 2007, s. 244-253Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of the project has been to evaluate and possibly improve the degree of industrialization and productivity when constructing bridges in full scale. Earlier theoretical studies have indicated that, if prefabricated reinforcement, self compacting concrete (SCC) and permanent formwork are used the degree of industrialization can be increased markedly. To be able to realize this, Lean Construction principles prove to be important utensils during the planning and design phase as well as during the construction of a full scale project.Throughout the design and planning of this first full scale bridge project, intensive contacts between designer, contractor, client and material suppliers were established. The design team concluded that the production time at site could be reduced with up to 20 % and the number of workers could be reduced by virtually 50 % during almost half theproject. This was realized by planning with Last Planner ideas, and designing the project properly using modern construction tools and materials. The design team also concluded that if the concrete class increased some of the very dense shear force reinforcement could be left out.The evaluated outcome of the demonstration project, i.e. potential productivity improvements, structural quality improvements, immediate feasible waste and cost reductions and the positive impact on the working environment, shows that the predicted benefits made were fulfilled.

  • 23. Simonsson, Peter
    et al.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Industrialized construction: benefits using SCC in cast in-situ construction2009Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 39, nr 1, s. 33-52Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As known the product SCC comprises many advantages compared with traditional concrete, but yet it has not changed the market of cast in place concrete as expected. This relates to some robustness problems of the concrete and to a general opinion that the product is considered to be expensive. However, manufacturers have improved their quality vastly and SCC has become more robust over the last few years. To increase the use of SCC, the actors of the building trade need to be informed and convinced how to benefit from all the advantages of SCC: i.e. the working environment the health and safety of the workers, the productivity etc. This paper deals with full-scale examples on the use and the realization of SCC obtaining several benefits during a projects whole construction time. Specially, the economics and the working environment are treated.

  • 24.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Industrialized construction with SCC obtaining many important benefits2008Konferansepaper (Annet vitenskapelig)
  • 25.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Industriallized construction with SCC obtaining important benefits2008Inngår i: Proceedings, Nordic Concrete Research, Bållsta, Sweden: [ ... XXth Symposium on Nordic Concrete Research & Development ... The current proceedings contain 90 summaries of oral poster presentations] / [ed] Johan Silfwerbrand, Oslo: Norsk Betongforening , 2008, s. 178-179Konferansepaper (Fagfellevurdert)
  • 26.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Robust self compacting concrete for bridge construction2011Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 2011, nr 44Artikkel i tidsskrift (Fagfellevurdert)
  • 27.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Kjellström, Robert
    Nordmark, Lars
    Lönsamt att industrialisera och effektivisera brobygge2008Inngår i: Husbyggaren : bygg, el, VVS, anläggning, ISSN 0018-7968, nr 2, s. 22-28Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Om bygget av en bro projekteras i ett tidigt skede och sedan sker med nya arbetsmetoder kan brobygget bli en fjärdedel billigare. Samtidigt minskar tunga lyft för byggarna. Det är lönsamt att använda Lean-filosofins sätt att tänka långsiktigt.

  • 28.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Rwamamara, Romuald
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Consequence of industrialized construction methods on the working environment2007Inngår i: Lean Construction: A New Paradigm for Managing Capital Projects - 15th IGLC Conference, East Lansing: Michigan State University Press, 2007, s. 302-311Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Traditionally, the working environment has been poor especially when it comes to steel reinforcement and concrete casting on construction sites. Industrialised construction methods such as self compacting concrete (SCC) casting and prefabricated steel reinforcement are creating a basis for an improved working environment. By using these methods, it is assumed that the cost for sick leaves due to ergonomic injuries and accidents are reduced as health and safety risks inherent to the traditional working methods are decreased. Observations along with video filming and informal interviews were performed. With a sequence-based activity method ErgoSAM, an ergonomic risk analysis was conducted. The analysis showed that industrialised methods reduced ergonomic workload on concrete workers.  The industrialisation of the production process through the introduction of innovative construction methods has benefited the construction workplace environment as well as the customer value in terms of improved material handling, elimination of additional adverse affect on health of handling vibrating tools, reduced on site congestion and reduced over all material costs.

  • 29.
    Simonsson, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Rwamamara, Romuald
    Ergonomic exposures from the usage of conventional and self compacting concrete2009Inngår i: Proceedings IGLC 17: 17th Annual Conference of the International Group for Lean Construction / [ed] E. Hirota; Y. Cuperus, 2009, s. 313-322Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The use of ergonomic production methods in concrete casting does have a significant human, social and financial impact in terms of the reduction of occupational injuries and related injury compensations. This paper presents a case study of comparative analyses of the ergonomic situations for concrete workers casting with two different types of concrete, namely the conventional concrete and the self-compacting concrete (SCC). Analyses were conducted with two methods for the identification of ergonomic hazards; and in comparison to conventional concrete, the analysis results have shown that SCC consistently gave significant improvements in work postures and led to less workload and noise exposure among concrete workers. The combination of lean thinking and ergonomics result in a system where  the worker is as efficient, safe, and comfortable as possible during the concrete casting work process. Material handling plays a significant role in lean construction by keeping the worker at the center and ameliorating many of the ergonomic problems that would otherwise remove the person from the production process. Transportation and unnecessary motion are two of the seven types of wastes that can be significantly reduced with the implementation of an ergonomic production system such as SCC that eliminates awkward work postures and vibrating tools. With the correct ergonomic material/product used in production of concrete structures, waste can be removed from the production system, thus creating an increase in production, decreased costs, an increase in quality of the product and less absence of workers in the future due to less stressful work.

1 - 29 of 29
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