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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.
571

Metodval i projekteringsfasen : Bostadshus Ljusbojen 1

Eklund, Johan, Larsson, Emil January 2007 (has links)
This major project in Building Engineering has its focus on inquiring into what methods has been used in the planning process of the residential building Ljusbojen 1. This project has been conducted in cooperation with Kadesjös Ingenjörsbyrå AB, an engineering contractor firm which also acts as the property developer. Initially several different general methods for planning residential buildings have been presented. After the methods from the process of building Ljusbojen 1 has been analyzed compared to the general methods presented in part 1. This shows what the determining factors are during the planning process; factors such as cost, quality, time management, know-how and environmental issues. Ljusbojen 1 has been a good building to study as it has a quite rare architecture and is meant to be perceived as a luxurious resident. The building has been divided into several different parts as this is how they are in the presented in offers, also the different parts are more easily analyzed; the parts are: foundation preparation, framework, exterior, rooming complements and installations. The basis of information has been extracted from relevant literature, planning project reports and in-person interviews. As the scope of this project covers a large field work has been concentrated on the most interesting methods. As a general result it can be determined that the building industry has been pressured to develop and try new methods mainly because of new and daring architectures. However, many existing and well known methods are still in use as the companies know that they work and can offer lower price from these.
572

Faunapassager : How animals cross roads

Lundberg, Adina, Gunnarsson, Fredrik January 2008 (has links)
A fauna passage is a way for animals to cross roads separated from the traffic. In Sweden, there are an unknown number of passages with different functions and appearances. These passages would, with the question “Which fauna passages can be found in Sweden, and how well do they work?” as a base, be compiled in a comparable way. This would be done with a number of questions asked to the different regions of Vägverket. The essay was delimited to only include ecoducts, animal bridges, landscape bridges, animal gates, tunnels for small animals, shore passages and fence openings. Most of Vägverkets regions had poor documentation of their passages and lacked the time to improve it. Most questions could only be answered for the region in general, and not for every passage, which forced us to change our way of account. In the end, most of the questions were answered by every region, even though it had not seemed possible earlier. Almost all regions also accounted for all their pas-sages in tables and with selected pictures to illustrate the passages. The compiled result showed that there were no ecoducts in the country and the passages directed to otter was clearly dominating. There were only a few passages constructed for larger animals, such as deer and elk, but those existing were better documented and followed up, than the smaller passages. It is likely that a lot of animals use regular road bridges and tunnels, but there is no documentation of this. The smaller passages are often planned in a simplified way, sometimes only through discussion in field. This often gave a fully sufficient and functional result, but there are examples of passages which did not function alright due to simplify-ing and inadequate planning. The passages varied in shape in the different regions, which all seemed to prefer certain kinds. It was not clear from the basic data if this depended on climate dif-ferences between the regions, or if it simply was a question of taste.
573

Den inbjudande cykelvägen / The inviting bicycle path

Lager, Viktor, Oskarsson, Matina January 2008 (has links)
No description available.
574

The contractors choice of material for sewer / Entreprenörens materialval för självfallsledningar

Olsson, Axel, Sjölander, Rickard January 2008 (has links)
Abstract This report is performed in collaboration with NCC Construction Sverige AB and treats sewers from the contractors’ point of view. The report investigates in an overall way how the work with sewers works in a contract company and which factors that speak for the different pipe materials, plastics and concrete from an overall economic perspective. Today both tubes and wells made of plastic as well as concrete are used and marketed. The report describes which factors that influence the choice of pipe system, plastics or concrete. The plastic materials that the report treats are polyethylene (PE), polyvinyl chloride (PVC) and polypropylene (PP). The studies for the work have been performed in four parts. The first part comprises literature studies of materials from researchers, sector organizations and companies. The other part comprises interviews and the third part site visits. Those persons who have been interviewed are active within the civil engineering construction division at NCC Construction Sverige AB in Jönköping and have occupations as calculator, purchaser, place manager, overseer and construction worker. The site visits are carried out at three workplaces nearby Jönköping, the house exploitation area Samset, the industry establishment of food industry and the street and water/sewer pipe project at the industrial area of Torsvik. The fourth part is a calculation that shows the overall economic for disposition of different dimensions of plastic - and concrete tubes. The result of the studies shows that work with sewers is a complex reality. The work is influenced by a large number of factors, for example; weather, the properties of the soil materials, the purchasing economic frames and the properties of tubes- and well material. A workplace that one day has normal productivity is the next day in risk of considerably lower productivity because of unfavorable weathers in co-operation with the geotechnical properties of the soil. When it comes to material choice for tubes and wells the study shows that there is a number of situations where either plastics or concrete can be recommended. The conclusions of which material that is best suitable are based on the purchase cost, the work cost and the production technical advantages, i.e. an overall economic perspective. / Sammanfattning Detta examensarbete är genomfört i samarbete med NCC Construction Sverige AB och behandlar självfallsledningar ur entreprenörens synvinkel. Rapporten utreder övergripande hur arbetet med självfallsledningar går till i ett entreprenadföretag och vilka faktorer som talar för de olika ledningsmaterialen plast och betong ur ett totalekonomiskt perspektiv. Idag marknadsförs och används rör och brunnar av både plast och betong. Rapporten beskriver vilka faktorer som påverkar valet av ledningssystem. De plastmaterialen som rapporten behandlar är polyeten (PE), polyvinylklorid (PVC) och polypropen (PP). Studierna för arbetet har genomförts i fyra delar. Första delen består av litteraturstudier av material från forskare, branschorganisationer och företag. Andra delen består av intervjuer de personer som intervjuats är verksamma inom anläggningsavdelningen på NCC Construction Sverige AB i Jönköping och har arbetsuppgifter som kalkylerare, inköpare, platschef, arbetsledare och anläggningsarbetare. Tredje delen utgörs av studiebesök de är genomförda på tre stycken arbetsplatser i närheten av Jönköping, villaexploateringsområdet Samset, industrietablering för livsmedelsindustri och gatu- och VA-projekt på Torsviks industriområde. Fjärde delen är en kalkyl som visar totalekonomin för läggning av olika dimensioner av plast- och betongrör. Resultatet av studierna visar på att arbete med självfallsledningar är en komplex uppgift. Arbetet påverkas av en mängd faktorer, till exempel väder, markmaterialets egenskaper, upphandlingens ekonomiska ramar och rör- och brunnsmaterialets egenskaper. Den arbetsplats som ena dagen har normal produktivitet kan nästa dag ha betydligt lägre produktivitet på grund av ogynnsamt väder i samverkan med markens geotekniska egenskaper. När det gäller materialval för rör och brunnar visar studierna på att det finns ett antal situationer där man kan rekommendera plast eller betong. Slutsatserna för vilket material som är bäst lämpat grundar sig på inköpskostnad, arbetskostnad, och produktionstekniska fördelar, det vill säga ett totalekonomiskt perspektiv.
575

Predicting shear type crack initiation and growth in concrete with non-linear finite element method

Malm, Richard January 2009 (has links)
In this thesis, the possibility to numerically describing the behaviour that signifies shear type cracking in concrete is studied. Different means for describing cracking are evaluated where both methods proposed in design codes based on experiments and advanced finite element analyses with a non-linear material description are evaluated. It is shown that there is a large difference in the estimation of the crack width based on the calculation methods in design codes. The large difference occurs due to several of these methods do not account for shear friction in the crack face. The finite element method is an important tool for analysing the non-linear behaviour caused by cracking. It is especially of importance when combined with experimental investigations for evaluating load bearing capacity or establishing the structural health. It is shown that non-linear continuum material models can successfully be used to accurately describe the shear type cracking in concrete. A method based on plasticity and damage theory was shown to provide accurate estimations of the behaviour. The methods based on fracture mechanics with or without inclusion of damage theory, overestimated the stiffness after crack initiation considerably. The rotated crack approach of these methods gave less accurate descriptions of the crack pattern and underestimated the crack widths. After verification of the material model, realistic finite element models based on plasticity and damage theory are developed to analyse the cause for cracking in two large concrete structures. The Storfinnforsen hydropower buttress dam is evaluated where the seasonal temperature variation in combination with the water pressure have resulted in cracking. With the numerical model the cause for cracking can be explained and the crack pattern found in-situ is accurately simulated. The model is verified against measurements of variation in crest displacement and crack width with close agreement. The construction process of a balanced cantilever bridge, Gröndal Bridge, is numerically simulated and a rational explanation of the cause for cracking is presented. It is shown that large stresses and micro-cracks develop in the webs during construction, especially after tensioning the continuing tendons in the bottom flange. Further loads from temperature variation cause cracking in the webs that is in close agreement with the cracking found in-situ. The effect of strengthening performed on this bridge is also evaluated where the vertical Dywidag tendons so far seem to have been successful in stopping further crack propagation. / QC 20100730
576

Real options in real estate

Gunnelin, Åke January 2000 (has links)
This is a doctoral dissertation presented to the FacultyBoard of the Royal Institute of Technology. The dissertationconsists of three self-contained essays on real option pricing.Essay I, written in Swedish, was presented at seminar andaccepted as fulfilling the requirement for a Licentiate Degreein Engineering thesis in 1995. Essay I: This essay studies the option to develop vacantland when the landowner simultaneously determines the optimaldensity and timing of a development. Williams (1991) andCapozza and Li (1994) have recently studied the landdevelopment decision from a realoptions perspective. Bothpapers assume that the production technology is of the commonlyused Cobb-Douglas type, but they use different assumptionsabout uncertainty over future rents and construction costs. Ananalysis of these models and their limitations is carried outand as a result valuation models based on other productiontechnologies than the Cobb-Douglas technology are derived. Essay II: McDonald and Siegel (1996) show that when thebenefit from an investment and the investment cost are assumedto follow correlated geometric Brownian motions, the optimalinvestment policy is given by a simple rule: Invest the firsttime the benefit-cost ratio reaches a certain level. In thisessay, which models the decision to change the use ofaproperty, the investment rule is found to be more complicated.Optimal redevelopment will take place for differentbenefit-cost ratios depending on the relative sizes of thevalue of the property in the different uses and the cost ofchanging the use. Also, for a given current benefit-cost ratiothe value of the option to change use will vary significantlydepending on the relative sizes of the state variables. Essay III: The relationship between the option to choose thecapacity of a real estate development and deliberateoverbuilding is studied in a simple model of investment underuncertainty. The model provides an intuitive measure ofdeliberate overbuilding: the difference between the number ofrental units the owner of an undeveloped site optimally choosesto produce and the number of units expected to be leased at thetime of the building's completion. Numerical simulations withreasonable parameter values show that in some economicenvironments, the optimal production strategy can be to producemore units than are expected to be leased at completion of thedevelopment. / <p>QC 20100611</p>
577

Länken / The Link

Larsson, David January 2014 (has links)
Platsen Tunnelbanestationen Stadshagen med uppgång mot Mariedalsvägen befinner sig som ett möte mellan många platser. Vi möts av parker, en framför och en bakom sett från tunnelbanans utgång. Ett stenkast härifrån har vi Stadshagens idrottsplats i öst, Nybyggda området kring Hornsbergs Strand i väst, kolonilotter i norr, Karlbergs slott för den som går ännu en bit norrut, men framförallt mötet och länken mellan parkerna, området och tunnelbanan. Utan tunnelbanan skulle platsen förlora stor del av den aktivitet som här råder. Min uppgift: Att förtydliga länken mellan tunnelbanan och platsen. Länkarna Jag låter mötet mellan tunnelbanan och byggnaden bli ett gym som relaterar till konsten i tunnelbanan och idrottsplatsen en bit längs med Sankt Göransgatan. Gymmet fortsätter ut i parken och således skapas en länk mellan park och byggnad. Detta tillsammans med den trappa som fortsättningsvis knyter samman park och tunnelbana. I mötet mellan parken och tunnelbanan hamnar ingången till bostadsdelen som större delen av byggnaden består av. Konstruktionen fortsätter att relatera till tunnelbanan. Byggnaden bärs av balkar och pelare i betong och får en putsad fasad som låter sig avslöja sin underliggande konstruktion. Att dra in byggnaden från gatan förtydligar tunnelbanan ytterligare och vi låser upp för utomhusaktivitet ovanför. / The location Metro Station Stadshagen with the exit to Mariedalsvägen is located like a meeting between many places. We are greeted by parks, one in front and one behind us as seen from the subway exit. A stone's throw from here, we have Stadshagens sports ground in the east, the area around the newly built Hornsbergs Strand in the west, allotments to the north, Karlbergs Slott for those who goes further a bit north, but most of all the meetings and the links between the parks, the area and the subway. Without the metro the site would lose much of the activity that we find here. My task: to clarify the link between the metro and the location. The links I let the meeting between the underground and the building become a gym that relates to the underground system and the sports ground a bit further on along St. Göransgatan. The gym continues out of the park, thus creating a link between the park and building, this together with the staircase that continues linking park and subway. In between the park and metro we place the entrance the residential parts of the building. The design continues to relate to the subway. The building supported by beams and columns in concrete are given a polished facade that allows itself to reveal its underlying structure.
578

Klimatdeklarationer och byggnaders miljöpåverkan : Utvärdering av byggnaders miljöpåverkan utifrån krav på klimatdeklaration: En fallstudie

Marceau, Norea, Fogelmark, Vangelis January 2021 (has links)
In January 2022, a new requirement will be introduced for declaration of building’s carbon footprint, which is a comprehensive requirement compared with previous regulations. This will hopefully lead the industry in the direction to achieve a net zero carbon footprint by 2050. This study explores the challenges and opportunities of this new requirement to serve as an approach to make more environmentally friendly choices. Many companies currently lack relevant knowledges to perform and evaluate building’s carbon footprint and thus may find this requirement challenging. The purpose of the study is to motivate construction companies and explore the benefits of this requirement in reducing CO2 emissions. This research work is focused on a building case which was built recently by a small construction company. The company runs by some craftsmen and it can therefore be a challenging task to understand and fulfil this requirement. In this study, a life cycle analysis is performed using the documents and materials obtained from the construction company. The declaration requirement concerns mainly the materials used in the building envelope as well as interior walls and load-bearing structures. The requirement is set on the CO2 emitted from production of building materials and components off-site along with on-site production of buildings (i.e. modules A1-A5 in a building's life cycle). The same scope is also applied in the study to analyze CO2 emissions. The analysis was performed in accordance with the recommendations of the Swedish National Board of Housing, Building and Planning, in the OneClickLCA (LCA tool) and by using specific data (ie environmental product declarations) and also more generic data that best represented the case. The results showed that modules A1-A5 were contributed to approximately 94.8 kgCO2e/m2 floor area. The materials with order of high to low CO2 emissions were respectively metal, insulation, wood and gypsum boards. Replacement of the insulation and gypsum boards to more environmentally friendly alternatives provided significant carbon footprint reductions. In addition, the CO2 emissions caused by the transport of wood materials could be reduced through replacement to more local alternatives. As a result, the new scenario which adopted all these alternative solutions could result in approximately 77.68 kgCO2e/m2 floor area which was almost 18% lower than the CO2 emitted from as-built design of the building case.   The conclusion of the study could be summed up that (1) there is an environmental benefit by using locally produced materials, (2) significant reductions in carbon footprint could be obtained by replacing materials to more environmentally friendly ones, which were also produced locally. All these indicated that the requirement on climate declaration can form the basis for making more conscious choices and reduce the carbon footprint of buildings from a life cycle perspective.
579

Effektivisering av byggprocessen med hjälp av lean : En fallstudie på ett företag med prefabricerat byggande

Alhajjaj, Eman, Sanchez, Marvin January 2022 (has links)
The increasing housing shortage occurring in society has for a long time created a great need to build housing quickly and cost-effectively. This has led to more and more industrialization of its building process, where housing is manufactured in modular form in the factory. With industrial processes, companies can give freedom to workers to take responsibility for the process in which they participate, and thus contribute with improvements and standardization in the process. One concept that is very suitable for this is The Toyota Production system (TPS), also called Lean production. Today, there are studies where Lean has been combined with the building process. The purpose of this study is to investigate and study whether the building process for prefabricated houses can be streamlined using the Lean method and, if so, how. As an efficiency improvement is sought in this study, questions about the basic principles of Lean will be involved. A qualitative data collection is done, which is based on an interview study. The questions for these interviews have been formulated with the help of literature contained within the subject. The interview questions are structured by being open where the respondent is given the opportunity to speak freely and in detail about the topic. Two companies were selected for this study. One company is a Stockholm stationed company that deals with prefabricated construction. These do not use the Lean working method as standard in their work. The other company is a company that also deals with prefabricated construction on a larger scale and that they use the Lean working method throughout their organization. The theory behind the study is the actual implementation of Lean in an existing building process that does not use the working method. By introducing Lean's basic principles into a company that does not use it today, this study will describe what elements can be applied from Lean's perspective. Finally, improvement measures, based on Lean's principles, are being introduced to improve and streamline the construction process of prefabricated construction at the particular company where the study was conducted. The aim of the study is to describe and analyze the construction process for industrial companies, the obstacles that arise in the process and how can Lean streamline the construction process from the 14 principles. Key-word: Efficiency, Lean, Prefabricated, Modular house, Construction, Construction process, Elimination, The Toyota Way, Lean principle / Den ökande bostadsbristen som sker i samhället har under en lång tid skapat ett stort behov av att bygga bostäder snabbt och kostnadseffektivt. Detta har lett till att mer och mer har industrialiserat sin byggprocess där bostäder tillverkas i modulform i fabrik (Wasana, Gunatilake, &amp; Fasna (2019). Med industriella processer kan företagen ge frihet till arbetare att få ansvar för den process de medverkar i, och därmed bidra med förbättringar och standardiseringar i processen. Ett koncept som lämpar sig väldigt väl för detta är The Toyota Production system (TPS), också kallat Lean production. Lean är utvecklad och anpassad för bilindustrin. Idag finns det studier där Lean har kombinerats ihop med byggprocessen. Syftet med denna studie är att utreda och studera om byggprocessen för prefabricerade hus kan effektiviseras med hjälp av arbetsmetoden Lean och isåfall hur. Eftersom att en effektivisering söks i denna studie kommer frågor kring grundprinciperna för Lean involveras. En kvalitativ datainsamling görs som är baserad i form av en intervjustudie. Frågorna till dessa intervjuer har formulerats med hjälp av litteratur som är kopplat till ämnet. Intervjufrågorna är strukturerade genom att vara öppna frågor där respondenten får chans att tala fritt och detaljerat om ämnet. För denna studien valdes två företag. Ena företaget är ett Stockolms stationerat företag som sysslar med prefabricerat byggande. Dessa använder sig inte av arbetsmetoden Lean som standard i sitt arbete. Andra företaget är ett företag som också sysslar med prefabricerat byggande i större skala samt att de använder sig av arbetsmetoden Lean i hela sin organisation. Teorin bakom studien är själva implementeringen av Lean i en befintlig byggprocess som ej använder sig av arbetsmetoden. Genom att införa Leans grundprinciper i ett företag som idag inte använder sig av detta ska denna studie beskriva vilka moment som finns att tillämpa sett ur Leans perspektiv.  Avslutningsvis framförs förbättringsåtgärder, baserat på Leans principer, för att förbättra och effektivisera byggprocessen av prefabricerat byggande på just företaget där studien är gjord. Studiens mål är att beskriva och analysera hur byggprocessen för industriella företag ser ut, vilka hinder som uppstår i processen samt hur Lean kan effektivisera byggprocessen ur de 14 grundprinciper.  Nyckelord:  Effektivisering, Lean, Prefabricerade, Modulhus, Konstruktion, Byggprocess, Eliminering, The Toyota Way, Lean principer.
580

Byggnadsteknik hos villor byggda på 1960-talet / : Building technology of small houses built in the 1960’s

Östman, Robin January 2017 (has links)
In Sweden during the 1960’s there was a housing shortage. To reduce the housing shortage, and to increase the living standard, a lot of new houses were built in Sweden in the 1960’s. To be able to build these houses some quick, new and unproven materials were used and some- times also unsuitable construction solutions and ground conditions. That lead to a lot of these houses suffered from mold in a relatively big extent. The most damaged components are the ground constructions, the attic or the outer wall. This is often due to inaccurate building mate- rials or insulation, and flaws in the ventilation. Many of the small houses built in the 1960’s suffers from problems and damages due to mois- ture and it isn’t always easy to find the cause of these problems. The purpose of this work is to illustrate the most common problems connected to the building technology in the 1960’s and what remedies there are to fix these problems. There are many different products and solutions available on the market today and for some- one who isn’t educated in the subject it can be confusing to know what is best for their house. This thesis presents the most common solutions available today and illuminate their pros and cons. Advice is also given about how to maintain and examine the house to increase the life- span of the house. The majority of this thesis focuses on the theoretical background of some of the most com- mon problems and different types of solution to those problems. The parts that are included in this work are the building envelope, harmful materials, ventilation, heating and the surround- ing ground conditions. Interior problems, in for example kitchen and bathrooms, are not in- cluded in this work. This thesis ends with an explanatory case study of a typical small house built in the 1960’s to see how the theoretical part matches the problems found in reality. The house is examined for the most common problems treated in the theoretical part, and explanations and advices is given to the found problems. This thesis is primarily aimed to provide solutions for small house from the 1960’s. The writ- er wants to give the reader an understanding about the problems that can be expected in those house and what can be done to identify and avoid these problems. / På 1960-talet rådde det stor bostadsbrist i Sverige. För att minska bostadsbristen och öka lev- nadsstandarden byggdes det väldigt mycket hus och lägenheter i Sverige då. Det skulle alltså byggas många nya småhus och för att kunna bygga dessa hus snabbt användes många nya och oprövade material. Även olämpliga konstruktionslösningar användes och markförhållanden var många gånger dåliga. Det, tillsammans med bristande fuktkunskaper, har lett till att många av de husen som byggdes på 1960-talet lider av mögelpåväxt eller mögellukt i minst en byggnadsdel. De mest utsatta byggnadsdelarna är grundläggningen, ytterväggen och vin- den. Många villor byggda på 1960-talet lider alltså idag av fuktproblem och fuktskador och det är inte alltid lätt att hitta orsaken till de problemen. Syftet med det här examensarbetet är att be- lysa de vanligaste problemen som är kopplade till villor byggda på 1960-talet och vilka åtgär- der som finns för att lösa de problemen. Det finns idag ofta många olika produkter och lösningar på marknaden och för någon som inte är insatt kan det vara en djungel att veta vad som är bäst för sitt hus. Det har arbetet redovisar de vanligaste lösningarna som finns på marknaden idag och belyser deras för- och nackdelar. Det ges även råd hur villan bör underhållas och undersökas för att öka livslängden på huset. Större delen av det här examensarbetet inriktar sig på den teoretiska bakgrunden till varför vissa problem uppstår och vilka konsekvenser olika typer av lösningar ger. Det som behandlas är klimatskalet, skadliga material som användes, ventilation, uppvärmning och den omgi- vande marken. Arbetet avslutas med en fallstudie av en typisk 1960-talsvilla för att se hur väl de teoretiska delarna stämmer överens i verkligheten. Villan undersöks efter de vanligaste problemen som finns i den teoretisk delen och sedan ges en förklaring till varför de har uppstått och råd över lösningar till de funna problemen. Det här examensarbetet riktar sig främst till att tillhandahålla lösningar för småhus byggda på 1960-talet. Författaren vill ge läsaren en förståelse om de problem som kan förväntas i huset och vad som kan göras för att identifiera och undvika de problemen.

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