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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Reducing Carbon Dioxide Emissions in Transport Infrastructure Projects

Krantz, Jan January 2017 (has links)
On- and off-site construction activities during transport infrastructure projectsare major contributors to greenhouse gas (GHG) emissions. The SwedishTransport Administration (STA) has stated the goal of gradually reducing itsemissions from transport infrastructure projects to zero by 2050. However,current life cycle assessment (LCA)-based approaches for estimating GHGemissions are static and location-independent, and thus do not account for thedynamics of construction. Some project-based methods have been proposed,but there is little guidance and insight available to facilitate theirimplementation in real projects during project planning.This thesis aims to explore how CO2 emissions can be reduced during differentstages of the planning process for transport infrastructure. The analysis focuseson emissions during project execution, i.e. on- and off-site constructionactivities including material production, and transportation. An exploratoryresearch approach is used to develop practical CO2 reduction methods thatcould be implemented during the feasibility studies, the design stage, and theprocurement stage of the planning process. These methods and models aredeveloped and demonstrated in case studies. This is a similar to the prototypingmethod in which early drafts of a new system are developed and tested toenable further development into a finalized system. The findings show thatconsiderable CO2 reductions can be achieved if project alternatives areevaluated systematically during the planning process. Although most majordecisions are made during the early stages of the planning process, later stagesshould not be ignored because these offer opportunities to include moredefinitive project data and thereby improve the certainty of the assessments.Future research in this area should look at the entire planning process up to thestart of construction.
12

Skapandet av en mall för kontrollplaner i NCCs projektportal / The creation of a template for self-control plans in NCCs project portal

Häggkvist, Mattias January 2016 (has links)
Egenkontroller bidrar i arbetet för att främja en god och gynnsam samhällsutveckling, genom att verifiera att en byggåtgärd uppfyller de krav som ställs från samhället på kvalitet och tekniska lösningar. NCC vill förenkla och effektivisera sitt arbete med kontrollplaner för egenkontroller genom att göra det möjligt att hantera dessa digitalt i deras interna datasystem som kallas projektportalen. Resultatet av arbetet är en mall för skapandet av nya kontrollplaner och som kommer att finnas tillgängligt för NCC i deras projektportal. Mallen avser uppförandet av ett koncepthus och kommer att uppfylla de krav som ställs från Plan- och bygglagen och går därför att använda som utgångspunkt vid uppförande av nya projekt. Genom detta hjälpmedel går det spara både tid och pengar samtidigt som NCC får en mer enhetlig kontrollplan som ser relativt lika ut från projekt till projekt. / By go through with a self-control during construction arrangements it will contribute to support a healthy community development by verify that the arrangements fulfills societys demand on quality and technical solutions. NCC now wants to simplify and make it more effective to establish a plan for the self-controls by make it possible to work with these in their computer system called projektportalen. The outcome of this master thesis is a template for the producing of a plan for self-control, and it will later be available to NCC in their computer system. The template intends building a ordinaly dwelling house and it will fulfill the legal requirement on planning and building that in sweden are called Plan- och bygglagen. Therefore it will be possible to use this template as a starting point when creating a new plan for self-control to a new constuction project. By using this template NCC will be able to save time aswell money and at the same time recive plans that looks the similary for every project that NCC will realize in the future.
13

Tillsatsmaterial i betong : hur påverkas den tidiga hållfasthetsutvecklingen

Lindelöf, Camilla, Ljungdahl, Anna January 2017 (has links)
No description available.
14

Slöseri med arbetstimmar inom svensk bostadsproduktion sett från en storskalig byggnadsentreprenör / Waste of working hours in Swedish housing production seen from a large-scale construction contractor

Söderberg Eriksson, Robert, Ströberg, Hampus January 2019 (has links)
Purpose: Time and resources are wasted away when efficiency within construction is stagnating. Despite being a generally developed industry, there is still light to shed upon the methods and implementation of norms and routines, resulting in unnecessary waste at the work sites. This report aimed to provide with further data in order to argue for a work place with reduced waste and a greater awareness around how a complex work site can be studied with the help of Muda theory. Method: A qualitative study with semi-structured interviews and a literature study as data collection methods. A total of nine interviews were accomplished with two foremen and seven carpenters. Foundation and understanding of the phenomenon were initially sought through literature. This to have an adapted form of interviews through the use of a custom template for the respondent and also to give the analysis theoretical foundation. Findings: The report shows three types of waste that come back more frequently, these are defects (rework), movement and waiting. To prevent waste, and primarily to discover it, the organization must make the clarity for Lean and Muda clearer for all employees. The project phase needs to prioritize where planning awareness about the schedule and building only after construction documents are essential. Furthermore, there is a great potential to improve the knowledge transfer between the projects where major entrepreneurs can benefit from their number of previous projects to systematically evaluate and improve their workplace. Here, a digital platform is proposed for this purpose. Implications: Compiling the analysis established that there are deficiencies within the work with Lean in production. Wastage that occur is caused by many different reasons and are often based upon inadequate planning within the organization. There are also external factors like delays and inefficiency to account for, although it is usually up to the contractor to optimize and adapt best way possible based on the current circumstances. A great emphasis has through this analysis been put on the work with planning with the help of The Last Planner System. It has also been concluded that a working system of knowledge transfer within an organization needs to be established in order to be a leading participant in Swedish building production. Limitations: This report has been angled so that the problem within production is illuminated. This since much of the wastage can be reflected to the design stage and future work can resume with such an angle. The validity of the report is lowered as a result of only screening one company although the report is limited to one Swedish, bigger contractor. In order to further confirm the reality of the problem, other forms of research could have been added, more than just literature studies and interviews, such as observational investigation. Keywords: Waste minimization, Lean Construction, Muda, Lean Production, The Last Planner System, Knowledge transfer
15

Just-in-time - En möjlighet för effektivisering i ett byggprojekt? / Just-in-time – A possibility for increased efficiency in a construction project?

Sundström, Ellen January 2019 (has links)
Vid dagens byggprojekt blir bristande utrymme på byggarbetsplatsen allt vanligare då det oftabyggs i tätbebyggda områden. Detta innebär att den traditionella lagerföringen påbyggarbetsplatsen blir svår och nya lösningar behöver hittas för att upprätthålla effektivitet ochgod arbetsmiljö.Just-in-time (JIT) har sitt ursprung i Lean och innebär att rätt material levereras tillbyggarbetsplatsen i rätt tid. Materialet lyfts sedan direkt in på sin slutliga plats i byggnadenistället för att lagras på byggarbetsplatsen.Syftet med denna studie är att undersöka hur företaget YIT Sverige arbetar i dagsläget och hurföretaget skulle kunna ha nytta av JIT vid byggnationen av en friidrottsarena i Gällivare.Friidrottsarenan byggs i tätbebyggt område och utrymmet är begränsat vilket innebär vissaproblem. Dessutom är Gällivare beläget i Norrbottens inland och avstånden till andra städer ärstora.Vid studien framkom att vissa problem som materialskador och bristande kommunikation frånleverantörer förekommer i olika projekt som YIT Sverige genomför. Dessa problem skullekunna undvikas genom användande av JIT. Det är dock svårt att beräkna de kostnader ellerkostnadsminskningar som JIT skulle kunna innebära då det aktuella projektet inte är genomförtännu och studien har en tidsbegränsning.Det finns även fler möjligheter för att förbättra effektiviteten och arbetsmiljö såsom metoden5S och att skapa långsiktiga relationer med leverantörer. Detta är en förutsättning för attanvända sig av JIT men även något som kan användas vid traditionell bygglogistik. Dessutomkan mellanlager vara ett alternativ om det inte finns möjligheter att fullt ut implementera JIT,det skulle innebära fördelar för effektiviteten och arbetsmiljön på byggarbetsplatsen även omalla fördelar med JIT inte nås. / During today’s construction projects lack of space on the construction site is becoming acommonly occurring problem since projects often are placed in urban areas. This means thattraditional storage on the construction site becomes difficult and new solutions need to be foundto maintain efficiency and good working environment.Just-in-time (JIT) originates from Lean production and means that the right material is deliveredto the construction site at the right time. The material is then directly placed in its final locationin the building instead of being stored at the construction site.The purpose of this study is to analyse how the company YIT Sweden is currently working andhow the company could benefit from JIT in the construction of an athletics stadium in Gällivare.The athletics arena is being built in an urban area and the space on the construction site islimited, which causes some problems. In addition, Gällivare is located in Norrbotten and thedistances to other cities are significant.The study showed that certain problems such as material damage and lack of communicationfrom suppliers occur in projects that YIT Sweden is managing. These problems could beavoided by using JIT. However, it is difficult to calculate the costs or cost reductions that JITcould bring as the current project is not yet finished, and the study has a short time frame.There are also other possible ways to improve efficiency and work environment such as themethod 5S and to create long-term relationships with suppliers. This is a prerequisite for usingJIT but also something that can be used in combination with traditional construction logistics.Another possibility is to use interim storage for material. It can be an alternative if there are nopossibilities for YIT Sweden to fully implement JIT. It would mean benefits for the efficiencyand working environment at the construction site even if the full potential of JIT is not fulfilled.
16

Säkerhet mot fortskridande ras för prefabricerade elementväggar : UNDERSÖKNING AV FLERBOSTADSHUS

Al Lafta, Hussein January 2019 (has links)
Progressive collapses may occur when a bearing wall is eliminated for various reasons. It can be a gas explosion or collision accident of a train or a vehicle, but also during renovation of a building component. After the wall has been eliminated, the building should be undamaged and not suffer a progressive collapse. Such an event can be avoided through a vertical link. The purpose of this study is to examine how secure today's vertical strap’sare against progressive collapse, and to find a solution for reduced risk of collapse Method: This study includes a literature review and a case study. The literature review was performed by a deepening of the existing literature that investigated the progressive collapse and the vertical drag strip. The studies found through the database Google school and Discovery. The case study was conducted in Kadesjös which is an engineering office where drawings and calculations were performed. Result: The result indicates that the vertical strap used today cannot withstand the design load if the entire wall (including the screw attachment) is eliminated. The threaded rod will then be pulled out of the floor and a progressive collapse occurs. By mounting a 70x70mm plate in the floor this can be prevented. Without the plate it takes only 58 kN to pull out the threaded rod from the floor, but with the plate the connection’s capacity is increased to 100 kN and then the anchorage pipe limits the capacity. Conclusion: The conclusion of this thesis is that a plate that increases the vertical strap’s capacity and thereby increases the safety against progressive collapse should be used.
17

Användning av vakuumisolering i klimatsmart hus : En fallstudie

Qeit, Harun January 2018 (has links)
No description available.
18

A learning 'learning' model for optimised construction workforce development

Ene, Gloria Unoma January 2017 (has links)
Integrating learning and work has become important for several reasons. The recognition that the key resources for wealth creation, knowledge and ideas are embedded in human capital. Furthermore, fast-paced advances in knowledge, technology, and access to information ensure that capabilities rapidly become obsolete. Continuous learning and workplace learning have therefore become essential. These developments have highlighted the pivotal role of learning in individual career development and organisational performance and the construction industry needs to address these issues. The construction industry, however, continues to report skill gaps suggesting that construction businesses need to consider creative ways to deliver skill-enhancing opportunities for their workforce. The challenge is global but has added significance for African emerging economies considering their developmental needs. Integrating workforce learning and development key practices into construction business was therefore the crux of this research which was aimed at developing a conceptual learning model that will enable construction firms to optimise performance in line with their business goals. Given the complexity of the construction domain and the need to allow integration of diverse processes, perceptions, experiences, practices and interactions, a pragmatic philosophical lens was employed allowing for a mixed methods research approach. A social constructionist ontology and a largely interpretivist stance was adopted. Surveys and case studies were conducted employing questionnaires, interviews and focus group discussions for data collection. Data analysis methods used were relative importance, correlational and constant comparative analyses. The research investigated the two main elements of learning systems the learner and the learning environment. The learner aspect found that emotional and social attributes were significantly associated with the performance of intermediate construction skills while key workforce practices emerged from the learning environment studies. These findings were integrated to develop the construction learning and development optimising model (CLEARDO). The research was limited to Nigeria because of its current focal position in the African economy.
19

Hållbar masshantering

Lindfors, Tobias January 2019 (has links)
Bakgrund: Bygg- och anläggningsbranschen står inför en stor utmaning med klimatreducerande åtgärder mot en klimatneutral byggprocess tills 2045. Denna studie är en uppföljning av ett exploateringsprojekt i Skellefteå Kommun med Skanska Sverige AB som entreprenör. Projektet har fått utmärkelse för årets hållbara infrastrukturprojekt samt mottagit Skanskas interna hållbarhetspris. Projektet har prisats för att ha reducerat den förväntade klimatpåverkan från masshanteringen med 93%. Nyckelord: Masshantering, Klimatkalkyl Syfte: Syftet med studien är att ta tillvara på lärdomar från det lyckade projektet Västra Eriksberg och finna nyckelfaktorer som har lett till det goda resultatet. Studien utreder också hur klimatkalkyl ska kunna användas som ett stöd i produktionen. Frågeställningar: -          Vilka nyckelfaktorer i projekt möjliggör/försvårar hållbar ”Masshantering”?   -          Kan produktionsstyrningen förbättras med hjälp av klimatkalkyl? Metod: Studien är utförd som en fallstudie. Intervjuer har utförts med nyckelpersoner kring Västra Eriksberg. Dokumentstudien har innefattat en undersökning av Skanskas produktionsverktyg. Slutsats: Det lyckade resultatet på Västra Eriksberg går att härleda till väl utförd projektledning tillsammans med en väl fungerande samverkan mellan beställare och entreprenör. Detta har tillsammans med gynnsamma geotekniska förhållanden, möjlighet till utrymme för upplag, närliggande verksamheter med behov av massor från projektet lett till ett väldigt gott resultat. För att klimatkalkylen skall kunna fungera som ett verktyg i produktionsstyrningen måste branschens fokus flyttas från den ekonomiska vinningen och låta klimatfrågan ta större plats. Vidare måste kalkylen få en närmare koppling till det verkliga utförandet och vara mer representativ för de arbete som utförs, detta kommer kräva en teknisk utveckling av produktionsverktyget för att göra arbetet med klimatkalkyl mer kvalitetssäkert och användarvänligt.
20

Timeefficiency of constructionwork in a developing country / Tidseffektivisering av byggarbete i Uland

Bruce, Linnéa January 2015 (has links)
Att arbeta tidseffektivt, strukturerat och inte spilla tid är viktiga faktorer vid ett byggarbete. Tid är pengar och desto längre tid ett arbete tar, desto mer pengar kostar det. Enligt teorin finns det ett flertal faktorer som påverkar effektiviteten på en byggarbetsplats. Några av dessa faktorer är struktur- och tidplaner, arbetsberedningar, planeringsmöten, metodförbättring och att identifiera mål. I Sverige arbetar man efter dessa faktorer på de flesta byggen, men i ett U-land är inte byggnationen lika utvecklad och man arbetar ofta dag för dag. Ett land som har problem med effektiviteten på arbetsplatsen är det fattiga landet Filippinerna i Asien. Under en volontärarbetsresa till Filippinerna observerades brister och tidsproblem vid byggnationen. Volontärarbetet ägde rum i en liten by vid namn Los Amigos utanför staden Davao. Arbetet gick ut på att bygga upp och renovera bostäder och området runtom byggnaderna åt rullstolsburna människor som inte har råd med ett eget hem. Vid sidan om volontärarbetsplatsen fanns även en byggarbetsplats som observerades under resan. Byggarbetsplatsen bestod av en basketplan. Denna studie syftar till att observera byggarbetet i Filippinerna för att identifiera problem med byggarbetet och effektiviteten på arbetsplatsen. Genom iakttagelser och intervju med en arbetsledare i byn Los Amigos har de olika tidsproblemen reflekterats och diskuterats. Utifrån de teoretiska referensramarna och med hänsyn till kulturen i landet har förbättringsförslag arbetats fram. Rapporten avslutas med två avsnitt som beskriver hur man kan arbeta mer tidseffektivt, strukturerat och undvika tidsförluster. Det ena avsnittet handlar om byggarbetet på volontärarbetsplatsen och den andra om arbetet på basketplanen som byggs i samma område. Arbetsplatserna är av helt olika karaktär och olika förbättringsförslag har därmed arbetats fram. / To work time efficient, structured and to not waste time are important factors at a construction work. Time is money and the more time a job takes the more money it costs. In theory, there are several factors that affect the efficiency at a construction site. Some of these factors are structural and schedules, work preparation, planning, method improvement and to identify targets. Most of these factors are used in construction work in Sweden, but the construction is not as developed in a developing country and they often work day by day. A country that has problems with efficiency in the workplace is the poor country Philippines in Asia. During a volunteer work trip to the Philippines was the deficiencies and timing problems during construction observed. Volunteer work took place in a small village called Los Amigos outside the town of Davao. The work was to build and renovate homes and the area around the buildings for wheelchair people who can’t afford their own homes. Besides the volunteer work was a construction site that was observed during the trip. The construction site is made up of a basketball court. This study aims to observe the construction work in the Philippines to identify problems with building work and efficiency in the workplace. Through observations and an interview with a supervisor in the village of Los Amigos have the different time problems been reflected and discussed. Based on the theoretical frameworks and taking into account the culture of the country have improvement proposals been worked out. The report ends with two sections that describe how to work more time-efficient, structured and avoid time losses. One section deals with the construction work on volunteer work and the other for a work on the basketball court built in the same area. The workplaces are of completely different character and various improvement proposals have thus been drawn up.

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