Purpose: This essay aims to examine the organizational and technical fire protection for the new emergency hospital in Västerås and analyze what measures are needed to ensure a safe hospital. By involving the staff and ensuring that they have the necessary knowledge and participation, one can ensure a safe care environment for the patients and create the conditions for dealing with potential dangers in an effective manner. Method: To achieve the objectives of the study the method involved carefully selected interviews with various professional roles possessing expertise in fire risks. Through these interviews, the aim was to attain a more comprehensive depiction of the results. In addition to the interviews, a versatile approach was adopted, encompassing surveys, site visits, literature reviews, and meticulous calculations of airlocks. Furthermore, data collection was augmented by utilizing documents from the Västmanland Region. Result: The outcome of the study showed a lack of knowledge, experience and ability to act when it comes to evacuation situations. The building was designed with fire safety in mind. Despite this, the opportunity to implement measures to further improve safety was identified. With regard to the building's fire protection, the possibility of implementing airlocks was identified to supplement and strengthen fire protection in departments where there were fewer fire cells. Conclusion: l the implementation of airlocks is important to improve the evacuation situation and safety. Regular evacuation drills should be prioritized to increase staff preparation and confidence. Measures such as clear fire separations, reliable fire alarm systems, automatic extinguishing systems and well-designed emergency escape routes need to be implemented to increase robustness and improve fire protection. This requires cooperation with fire safety experts. Airlocks can streamline the evacuation process for bedridden patients and staff, which is crucial for quick and safe evacuation in emergency situations. 

The purpose of the study was to explore how property management companies view of Building Information Modeling (BIM) as a working method in property management process, and to explore the companies efforts at BIM in terms of the level of detail on BIM object implementation in property management. The study includes both companies that have and do not have contributions in BIM. The exploration was aimed at two companies and their varying ways of working to inform the needs of BIM in property management. The purpose of the study was also to give a clear picture of how BIM tools should be defined in the management process. The work was used of qualitative methods to answer the questions first consisted of a literature review, interviews and case study. The case study was about BIM implementation in New Karolinska Solna. The result showed that the definition of BIM in property management companies is not clear yet. The companies have intended to use BIM, but they are not there yet, there should be a type of requirements list that works with planning and production and benefit from using BIM in the property management. According to respondents, most of the common reasons why BIM was not used were because the approach of the tool. There is no proper structure or common working method of how the tool would be applied. Many literature sources including respondents claimed that BIM seemed good and have a good potential to be the future work process. BIM leads to improved work environment, improved sustainability development, good marketing, increased quality in work, time savings, and improved project management. As a suggestion as to how BIM could be implemented, it can be described in a few steps, which is status analysis, identify the benefits of BIM, start implementing on a smaller scale, follow up continuously, improve and expand the work and last but not least Integrate information. The conclusions that can be drawn from the results and literature study were that BIM can improve the quality management of the properties, but it is important to find a reasonable level of BIM implementation as well as a suitable detail level of BIM-model.

Most construction companies want to deliver the best possible results for their customers while spending the least possible resources. Nevertheless, the construction industry has traditionally been full of unnecessary inefficiency regarding workflows. One of the most successful methods to prevent inefficiency workflow is lean construction. Lean construction consists of various methods that aim to streamline workflow as optimally as possible. Purpose: The purpose of the degree project is to use specific lean methods and tools to identify different waste and be able to use them to reduce downtime of a studied construction project. Method: A case study has been carried out where the project Heby - care homes has been studied. To gather more information a survey study has been done. To gather even further information about the project an interview was conducted with a person who has a leading role. Results: The result shows a analysis of the survey and the interviewe answers. It also includs working methods, transparency and waste minimization. Furthermore it includs solutions like identify problems, create order and structure, standardize and work on improvements. Conclusions: The conclusion that can be drawn is that standardizations in the form of checklists and guides need to be in each project. More openness and to review your chosen forms of agreement. To have a more dynamic working group that strives to achieve common goals and continuous improvements. These are the most important aspects of making a project effective.

Purpose: The purpose of this study is to analyse the positive impact of digitization on the production environment and challenges that may come along with digitalization. This study goes further on to looking into how to increase the use of digital tools. Method: The method used in this study is mainly based on an interview study, where interviews are carried out with expertise of the field of digitization. Literature study was used to compliment the interview study with previous scientific studies on the field. The literature used is based on scientific articles, reports, government reports and relevant previous studies related to the subject. Results: The results from the interview study showed that the use of digital tools had positive impact on the construction stage. The most important benefit of digitization is the information management. There are also economical and work environmental benefits as well as higher work productivity. However, there are no exact figures showing these profits. The result also shows what challenges can be encountered and how these challenges can be best avoided. In addition, this study highlights how the industry should go about increasing the use of digital tools. Conclusion: The conclusions that can be drawn are that digitization has positive impact in construction, but challenges can arise. These challenges can be avoided through cooperation between companies and participantes to achieve a more digitized construction stage.

This diploma work was performed because the company Sveriges BostadsrättsCentrum, with the abbreviation SBC, had a need to gain insight into how changes in the Work Environment Act and related regulations which took effect January 1, 2009 affecting their work with the work environment. The changes mean that the client may hand over his work environment responsibilities to a contractor and that he has to select so-called building work environment co-ordinators. At SBC they are working as representatives for tenant-owner's association when a construction is about to be carried out. The purpose was to ascertain how changes may affect the work at SBC. The diploma work intends to educate the staff at SBC how work with the work environment would look like if they met the regulatory requirements. The main issue that the diploma work deals with is whether SBC has the responsibility to select a building work environment co-ordinator for the planning and projecting before the contractor takes over responsibility for the work environment. Questions were answered by information from the Work Environment Act, AFS 1999:3 and other material from the Work Environment Authority. Two interviews with staff at the Work Environment Authority were also held. One of the conclusions drawn from the diploma work is that it’s the client who will select a building work environment co-ordinator for the planning and projecting. That should be done as soon as the planning and projecting has begun. The planning and projecting usually begins before the main contractor takes over responsibility for the work environment as the employee. It is not clear that SBC will take on the client’s responsibility to select a building work environment co-ordinator for the planning and projecting in the early planning, before the contractor takes on responsibility and there are several ways to do this.

Att bestämma vidhäftningen mellan prefabricerade element och senare pågjutning på arbetsplats är viktigt. Självkompakterande betong är en betongtyp som flera prefabricerade företag börjat använda på grund av dess goda egenskaper. Dock finns några oklarheter som behöver utredas vidare, exempelvis vidhäftningskapaciteten vid pågjutning. I och med införandet av Eurokod blev det större krav på skrovligheten jämfört med tidigare krav i BBK 04. För självkompakterande betong kan det vara svårt att få till en skrovlighet enligt både BBK och speciellt Eurokod. För undersökning av vidhäftningskapacitet kopplat till draghållfastheten finns beprövade metoder som följer svensk standard. Dock finns ingen svensk standard för vidhäftningsprov för skjuvhållfastheten, bland annat på grund av att för få undersökningar har utförts och att provnings-utförandet är mer komplext.

Syftet med denna undersökning är att jämföra olika mätmetoder för att mäta skjuvspänningar för vidhäftningen mellan prefabelement och pågjutningsbetong samt att också undersöka olika metoder för att mäta ytjämnheten. Målet är att identifiera skjuvkapaciteten i vidhäftningen samt få reda på vilken påverkan ytjämnhet och ytbehandling har för vidhäftningen. Detta för att utvärdera om Eurokod 2:s hårdare krav på skrovlig yta är nödvändig jämfört med BBK 04 med avseende på skjuvning. Ytor som ska jämföras är avdragen yta och yta som uppfyller BBK 04:s samt Eurokod 2:s  krav på skrovlig yta. Mätmetoder för skrovlighet ska undersökas för att senare utvärderas och användas i undersökningen.  Förutom dessa ytor som normalt förvattnas ska även en yta som följer BBK 04:s krav på skrovlig yta utan förvattning undersökas om förvattning har någon positiv inverkan på vidhäftningen.

Den mätmetod som valdes för att identifiera skjuvhållfastheten var L-formad Push-Off-metod, vilket dimensionerades med hjälp av en referensundersökning. Provkroppen tillverkades i Strängbetongs fabrik i Kungsör och innan pågjutningen utfördes mättes ytjämnheten på vidhäftningsytan med hjälp av Sand-Patch-metoden. För att bekräfta validiteten hos Sand-Patch-metoden användes också en annan mätmetod, så kallad Profilmall. Efter att ytorna var uppmätta och pågjutningen hårdnat skickades provkropparna till CBI Betonginstitut för skjuvhållfasthetsprovning samt tryckprovning.

Resultaten från undersökningen visade att inga större skillnader i skjuvhållfasthet mättes mellan Eurokods och BBKs krav på ytjämnhet, men det visade sig att den obehandlade ytan klarade av högst skjuvhållfasthet. Alla värden var betydligt högre än vad både Eurokod och BBK 04 anger för hållfasthetsklassen C45/55. Under provningstillfället upptäcktes sprickbildning vid 85 kN både i den befintliga betongen samt vid pågjutningen på de tunnaste delarna, för samtliga provförsök.

Utöver skjuvhållfastheten mättes även deformationer såväl vertikalt som horisontellt och det framgick tydligt i resultatet att vertikala deformationerna var mer än tio gånger större än de horisontella. Ingen skillnad mellan BBK och Eurokod kunde tydas vid vertikala deformationer, dock vid horisontella deformationer mättes Eurokod till tre gånger större horisontella deformationer jämfört med BBK. Detta tyder på att BBKs krav på skrovlighet är bättre än Eurokod ur deformationssynvinkel

Med denna undersökning som grund kan tillverkarna välja att avstå från Eurokod 2:s hårdare krav på skrovlig yta och fortsätta att behandla ytan enligt BBK 04. I och med detta menar författarna att Eurokod 2:s hårdare krav på skrovlig yta inte är nödvändig jämfört med BBK 04 med avseende på skjuvning (vidhäftning), vilket var det primära målet för undersökningen.

Purpose: This study aims to study the management of demolition waste in construction production in a major renovation project while proposing different improvement possibilities. Method: In this study the chosen method was literature study and a case study that was compared to a reference object. Furthermore, in the case study an interview was arranged with the site manager and a survey was conducted with a portion of the workers that were involved in this project. Results: The results show how NCC is intended to work efficiently and calculatedly when preparing a project. Furthermore, the results show the factors that have affected the project both directly and indirectly. In addition, some suggestions for improvement to achieve a smaller amount of waste are proposed. Conclusions: The conclusion is that NCC follows their guidelines for how to achieve sustainable demolition. In this project, they came in late, which meant that they did not fully succeed in planning well for the project. However, regarding the spontaneous measures that needed to be carried out, they received an acceptable amount of waste.

SAMMANFATTNING [SV]

Projektledarens ansvar i ett projekt är att leda sin projektgrupp till uppsatta mål med fastställda kravspecifikationer. Dessa mål skall vara uppnådda inom en tidsanpassad och ekonomisk ram. För att nå dessa ramar bör en projektledare tidigt planera genomförandet och upprätta en ekonomisk plan för projektet. De konsekvenser som uppstår vid komplexa projekt då projektledaren inte förfogar över tillräcklig med kompetens leder till ekonomiska förluster samt ett misslyckat projekt. Vilka kompetenser bör en projektledare behärska? På vilka sätt behärskas dessa kompetenser? Med vilka verktyg eller metoder kan kompetenserna utnyttjas vid planeringen av projekten för att undvika problem? Det är dessa frågeställningar som för ihop denna studie om projektledarens kompetensutveckling i mål av att ta fram en kompetensutvecklings modell.

Studien ger en blick över projektledningens alla stadier och vad projektledarens roll är i samtliga faser. Sedan beskrivs begreppet kompetens och hur individen utvecklar sin förmåga att leda projekt. Studien har genomförts i samarbete med byggföretaget JM AB där metoden för studien består av tre moment. En omfattande litteraturstudie har genomförts där det teoretiska perspektivet runt projektledning har analyserats. Intervjuer med projektledare och platsbesök genomfördes för en djupare förståelse över hur JM AB arbetar med tidsplaner och befintliga kompetensutvecklingsplaner.

Studien påvisar att projektledarna på JM AB är främst delaktiga i tidiga skeden samt det avslutande skedet. I förstudien och planeringen är de främsta arbetsuppgifterna för projektledaren att fungera som en ackvisitör, upprätta olika ekonomiska budgetar samt att ta fram en huvudtidplan för det aktuella projektet. I genomförandet är det av stor vikt att projektledaren skapar en god sammanhållning mellan de inblandade parterna. På så sätt alstras en god klarhet mellan projektmedarbetarna och produktionen effektiviseras. Vid ett projektslut är det kunden som står i fokus. Där en god kommunikation emellan kunder, projektledare samt mäklare ger upphov till de förutsättningar som kunden behöver för inflyttning är till hands.

Examensarbetet konstaterar att projekt oftast blir uppdelade mellan projektmedarbetare. Detta framför krav på att projektledaren ska inneha en bred kompetens, där helhetsbilden över projektet ansågs vara en viktig del av projektledarens kompetens. Följaktligen blir att fungera som kärnan i projektet kombinerad med den sociala kompetensen en central del. Vidare fastställde examensarbetet att projektledarens kompetensutveckling först och främst sker i det dagliga arbetet. Där erfarenhet från tidigare arbeten utgjorde den största kompetensutvecklingen. Förutom erfarenhetsläran bidrar även aktiviteter som formella kurser till en kompetensutveckling hos projektledaren.

Studien belyser dessutom projektledarens varierande planeringsverktyg, där även en jämförelse dras mellan planeringsverktygen Powerproject och Microsoft Project. Genom jämförelsen mellan programmen dras slutsatser angående för och nackdelarna med programmen samt hur dessa bidrar till mindre ekonomiska förluster.

SAMMANFATTNING

Det som projektledaren behöver tänka på vid planeringen av ett projekt är att uppnå beställarens krav på byggnaden och att skapa en bra samordning mellan de olika aktörerna som är inblandade i projektet. Dessutom måste projektledaren se till att projektet följer tidplanen och att budgeten inte överstiger de bestämda ramarna.

Därför ligger ett stort fokus på att projektledaren har bra grundkunskaper och tillräcklig kompetens samt kunskap. För att uppnå det optimala resultat som behövs för att kunna planera och strukturera projektet så smidigt som möjligt.

Detta arbete undersöker vilken kompetensutveckling och kunskap som behövs för att projektingenjören ska utveckla sina färdigheter i projektledning. En av de kärnfrågor som tas upp i intervjuerna är ”Vad kännetecknar en projektledare med låg respektive hög kompetens?” och ”Hur bedrivs kompetensutveckling för de anställda inom WSP?”

De mål som ska uppnås i detta arbete är att belysa vikten av kompetensutveckling och erfarenhetsåterföring. Resultaten av undersökningen har sammanställts i en handbok som beskriver vad en projektingenjör behöver fokusera på för att bli allt mer kompetent och utvecklas effektivare till en projektledare.

För att kunna uppnå dessa mål genomfördes en litteraturstudie för att få en bättre uppfattning av projektledarens roll. En mer detaljerad studie av projektingenjörens respektive projektledarens arbetsuppgifter gjordes. För att komplettera litteraturstudien genomfördes en datasökning via internet. Därefter utfördes en intervju med 5 projektledare och 5 projektingenjörer för att jämföra teori med praktik. Utifrån de intervjuades svar och litteraturstudiens resultat skapades en handbok som beskriver vad projektingenjören behöver utveckla för att bli en effektivare projektledare.

Examensarbetes slutsats visar att kompetensutveckling i grund och botten är bunden till den enskilda individens motivation till att utvecklas. Varje enskild individ har sina egna mål och de är stimulerade av varierande motivationsfaktorer. Några individer har som mål att bli VD för ett företag, medan andra är nöjda med deras nuvarande position och det innebär att alla projektingenjörer/ projektledare inte strävar efter en ständig utveckling. Uppsatsens huvudfråga var: ”Vilken kompetensutveckling behövs för att projektingenjör ska utveckla sina färdigheter i projektledning?”.

Resultaten visar att utan att lära sig av de fel och problem som tidigare gjorts samt göra egna nya misstag kan inte en projektingenjör utvecklas eller bli effektivare. Andra typer av vinster är tid som kommer att minska för att lösa vissa ständigt uppkommande problem med hjälp av kunskaper från tidigare liknande projekt. Genom att dra nytta av denna kunskap och inneha en bra erfarenhetsåterföring kan det bli enklare att hitta en effektiv lösning och på så sätt minska onödiga tidsförluster.

Syfte: Examensarbetet syftar till att undersöka var företagsverksamheter inom trafiksäkerhet och tillfällig trafikledning kan tillämpa visuell artificiell intelligens (AI) för att uppnå en säkrare, miljövänligare och mer kostnadseffektiv verksamhet. 

Frågeställningar: “Hur kan tillämpning av visuell artificiell intelligens användas för identifiering av temporära skyddsanordningar vid vägarbeten?”; “Hur kan tillämpning av visuell artificiell intelligens användas för identifiering av personlig skyddsutrustning vid vägarbeten?”; och “Vilka förändringar kan ske gällande företagsverksamhetens säkerhet, kostnader och koldioxidutsläpp vid tillämpningen av visuell artificiell intelligens vid vägarbeten?”.

Metod: Denna studie utfördes med en abduktiv ansats och en mixad forskningsdesign. Där en teoretisk referensram utifrån vetenskapliga artiklar och en empiriinsamling bestående av en fallstudie, intervjuer med anställda, och beräkningar baserat på data från fallföretaget analyserades för att besvara studiens frågeställningar.

Slutsats: Genom att adressera utmaningarna och utnyttja möjligheterna som teknologin erbjuder kan AI-kameror vara ett värdefullt verktyg för att främja en säkrare och mer hållbar arbetsmiljö vid vägarbeten samt en mer gynnsam verksamhet. Genom att tillämpa visuell artificiell intelligens, för att identifiera korrekt användning av personlig skyddsutrustning vid vägarbeten och kombinera det med manuella inspektioner, kan säkerheten för arbetare förbättras och korrekt användning av personlig skyddsutrustning (PPE) säkerställas. Slutligen indikerar studien att tillämpning av visuell artificiell intelligens vid vägarbeten har potential att förbättra säkerheten för arbetare, trafikanter och civilpersoner runtom, minska kostnaderna för företagen och minska miljöpåverkan genom minskade koldioxidutsläpp.

There are many indoor pollutants in the residentia lbuildings. Of those radon is a major and harmful indoor pollutant in most countries. Radon sometimes entries to the house through building materials. High insulation and tightness in order to increase energy efficiency and to lower energy costs is led to the indoor air quality problems. Ventilation is a good method to dilute radon contaminant and maintain indoor air quality. The more fresh air is brought into the indoor environment, the better the indoor air quality can be achieved, if the fresh air comes from non polluted ambient source. However ventilation can consume a lot of energy (currently 29-59% of energy building use), especially in cold climate same as Sweden, energy consumption could be much more. Though for coping with high energy consumption the building tightness is acted very well, but for ventilation plays against. This contradiction makes a poor indoor air quality. The aim of this paper is to simulate and visualize radon treatment and mechanical ventilation rates for achieving to indoor air quality. The Fluent (CFD) program software is employed for simulation.

Ninety percent of all single-family houses and smaller residential buildings in Sweden are built with timber frames. Though, this figure is different for higher buildings, about twenty percent in timber frames and eighty percent in concrete and steel. However, the knowledge and experience about tall timber houses is limited today and it needs to be developed over the time, both technically and architecturally. Purpose: The wood has a lower E-module than concrete and steel, which cause an additional problem in high-rise buildings of more than eight floors, stability. The measures for this problem can be costly and reduce the living space of the building due to large dimensions of the wooden structure. This project work is based on the challenges that exist around the construction of tall wooden buildings and tries to present a beneficial hybrid solution for the construction of tall houses in wood and concrete. Method: The study object is a multi-story building on ten floors where wood is used in combination with concrete for the frame system. The vertical loads such as self-weight, payload and snow load are carried by the wooden frame. On the other hand, concrete has the task of taking care of the horizontal forces caused by wind loads. The frame system is dimensioned according to the Eurocodes and standard dimensions to ensure the load-bearing capacity of the building. Results: The result reports that two concrete cores in the hybrid building absorb all horizontal forces and loads down to the foundation. These cores can also be used as stair/elevator shafts and will not affect the building's living area. A timber-concrete composite with a thickness of 300 mm, replaced the wooden composite which normally reaches a thickness of 400 to 500 mm. This means a height gain of one to two meters. The columns will get smaller dimensions because of the cores and give more living space. The concrete utilization in that hybrid building decreases by 57 percent, which is a large saving from an environmental perspective. In addition, life cycle analysis, LCA shows that carbon dioxide equivalents, CO2e are 43 percent less in the hybrid framework. Conclusion: The hybrid multi-stories houses of concrete and wood can be a useful alternative for increasing construction of wooden houses. A concrete core in the middle of building helps the construction to become more stable and the swaying due to wind loads be minimized. Furthermore, the columns can have smaller dimensions, which increases the living space in the building. The timber-concrete composite gives the building more weight and solves the step sound problem that arises due to low E-module on the wooden flooring. Additionally, the height of the building decreases, which in turn leads to buildings being able to have more stories and more living space. Moreover, through hybrid solutions in buildings, the environmental benefits of wood can be utilized to build environmentally friendly buildings. The ten-stories hybrid framework in this study, saves 43 percent CO2e compared to the corresponding framework in concrete. 

Markförstärkning i ett vägbygge kan göras på olika sätt. I detta examensarbete jämför vi två av dessa metoder, nämligen massutskiftningsmetoden och användning av kalkcementpelare ur energi- och miljösynpunkt. För att jämföra dessa två metoder togs fram ett excelbaserat räkneverktyg där resultatet av energiförbrukningen fås i kWh och koldioxidemissioner i ton CO₂. Denna jämförelse gjordes för ett specifikt vägprojekt som använde massutskiftningsmetoden för vägunderbyggnaden. Det som ingick i beräkningen var schaktning, fyllning, krossning, sprängning, transporter och kalkcementpelare. För denna uträkning användes data från både entreprenörer som var med i projektet och företag som hade dokumenterade data.

Metoden som förbrukade minst energi och som släppte ut minst koldioxidemissioner var massutskiftningsmetoden. Det som gjorde att kalkcementpelare till en sämre metod var den höga energiförbrukningen som krävdes för tillverkningen av kalk och cement. Det som krävde mest energi i tillverkningsprocessen var ugnar där höga temperaturer krävdes.

Skillnaden mellan utskiftningsmetoden och kalkcementpelare i objektet var att i massutskiftningsmetoden krävdes urgrävningar för att schakta bort jordmaterial med dålig hållfasthet och ersätta det med bergmaterial med hög hållfasthet. I denna metod går energi åt till schaktning, fyllning och transport. Medan förstärkningsmetoden med kalkcementpelare förbrukar energi för tillverkning, transport och installation. Eftersom metoden går ut på att vägbyggnaden ska vila på pelarna genom att borra ner dessa i marken istället för att schakta bort stora volymer och transportera dem till fyllningen så är det lätt att tro att kalkcementpelare sparar energi genom att minska massförflyttning och långa transporter. Resultatet av detta examensarbete har visat motsatsen.

As a structural engineer there is some knowledge concerning concrete that is essential to know. When designing buildings, it’s always of most importance to know how to dimension the necessary reinforcement for certain types of wall beams. It’s quite normal for a building to have wall beams. To calculate each wall beam in every project by hand is unnecessary process. The main purpose with this report is to help structural engineers increase their knowledge about wall beams. Theoretically explained and shown how the calculations work. This report also contains a calculation template and shows how to use the calculation template that has been designed to abridge the calculations of a structural engineer. The focus of this report lies in showing how the specific hand calculations are made and how those calculations have implemented in the excel file which dimensions the amount of required reinforcement for wall beams. Throughout the report it’s explained what conditions are necessary to know by the user of the template. Initially the theory behind wall beams analogy has been explained. It’s in the essence of this report to develop the understanding of each calculation being made. The theory has been completed with explanation of each calculated part and what necessary check-ups are obligatory. As a result, one actual example has been calculated. Firstly, by hand for it to then be compared to the calculations made by the template. This is to verify that the calculations being made by the template are indeed accurate.

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.

Purpose: The horizontal stabilization of a building is of great importance in the design of its structural system. Insufficient counteraction of horizontal loads can lead to problems where columns and beams deflect more than the allowable margins. One common horizontal load arises from wind hitting an exterior wall. In this study, four bracing types were analyzed using software to evaluate and compare them, taking various factors into account. The building upon which the study is based is an industrial four-story structure located in Västerås. The building is designed with hinged column bases, which require a stabilization system to maintain its stability. This study aimed to determine the optimal solution for the stabilization system by comparing multiple proposals (X, V, inverted V, and diagonal) considering all factors that significantly influence stabilization. The different proposals were compared in terms of material usage, horizontal displacement, and the number of spans required for steel bracing. Method: Hand calculations were used in this report to design various structural components such as columns, beams, and bracing, which were compared with FEM (Finite Element Method) designs. Additionally, different perspectives were considered within the relevant subject framework, including steel properties, general loads, characteristics, and descriptions of the examined models. Results: After conducting the calculations, it was found that the optimal number of spans required for bracing the industrial steel structure was 32 diagonal braces, placed in the outermost bays on all sides of the building at each floor. This proposal resulted in reduced material usage with a secure horizontal displacement, ensuring stability and durability of the building. Conclusions: In conclusion, this report provides a deep understanding of the importance of stability in buildings, especially when it comes to the safety of occupants and the structural integrity of the building. Proposal 1 has likely met the requirements based on all the calculations and analyzed models that have been conducted, and therefore, diagonal bracing has been chosen as the optimized solution.

Abstract

This degree project comprises 30 credits, i.e. 20 weeks of work. The work mainly deals with the energy balance for a multi-family house in Västerås and the requirements for energy conservation in the Swedish building code, BBR. Calculations of the energy balance are supplemented by a number of interviews.

Energy conservation in general has become more important in recent years and the subject is in line with increased public awareness. This importance and attention is explained by environmental problems in general and global warming in particular, but also by rising energy prices. The Swedish authority Boverket has gradually changed the regulatory framework in order to improve the energy efficiency for new buildings. Boverket issues the Swedish building code BBR which includes energy requirements for buildings. The new BBR 16 was published after only about 6 month after the previous version BBR 15.

This degree project includes a commission from the company Abetong AB to compare the previous BBR 15 against the new BBR 16 and find any changes, and compile these changes as clear as possible. The work also includes answers to some specific questions from the same company. One question is whether existing multi-family houses from the company would meet the new energy requirements of BBR 16. The energy balance of these houses is studied specifically when an exhaust air heat pump or a ventilation heat exchanger is used in order to save energy. To make this work particularly interesting, the window area was changed to see how this would affect the energy use in the buildings.

To answer these questions, the energy simulation program VIP+ was used for calculations. These computer calculations have also been supplemented by hand calculations as a control measure. All results from the different calculations are put together and analyzed in this report.

The overall conclusion from the calculation results is that the existing multi-family houses perform well with the present technology, and that they meet the new energy requirements in BBR 16. This means that no further measures in order to save energy in the houses are necessary in order to meet the newest requirements.

Västerås 2010-05-24

Seif Alamerison

This bachelor thesis aims to find a more sustainable and cost-effective solution for a rotation system used for turning walls. The work was carried out by the client Husmuttern AB, which requires a rotation system for rotating wall fixtures in the company's future construction projects in Scandinavia, as well as in Poland and Ukraine.

The current fixture is powered by an electric motor, which the company considers to be a costly and less sustainable solution. Therefore, this work will present a more cost-effective and sustainable solution and address the development process for the proposed design.

The research question for this thesis is: How can an existing electrically driven rotation system be replaced with a manually operated mechanical rotation system while ensuring that the design meets the internal requirements of Husmuttern AB and the external regulations from the Swedish Work Environment Authority regarding load ergonomics?

The work has been done with consideration for cost-effectiveness, ergonomics, and safety. Relevant regulations from the Swedish Work Environment Authority have been reviewed in the course of this work. The work has also focused on developing a concrete proposal where the use of standard components has been prioritized to save resources and result in a cost-effective solution based on available material dimensions from different suppliers.

Computer Aided Design (CAD) has been used to draw and assemble components that the rotation system's design consists in a virtual environment. CAD has been used with the help of Solidworks software to give a closer picture of what the construction might look like, as well as how the components sit and their position and direction.

The work has been completed within the specified time limit and delivers what was specified in the limitations. The result is a new rotation system - a manually operated mechanical rotation system that enables ergonomic and safe work tasks. The report describes the work process, calculations, drawing documents, and a user description of the rotation system's work tasks, thus constituting the delivery of the work.

With the world changing to a more sustainable society, the construction industry also wants to do its part and thereby build more carbon neutral. An alternative to the production of sustainable buildings is to relinquish from steel and concrete to focus on wooden building structure. This leads to major challenges for constructors both in terms of fire and the fact that wood has a low density compared to the previously mentioned materials. Purpose: The report will examine the problem of building tall buildings with a stabilizing body of cross-laminated timber (CLT) with focus on the coupling beam. Method: The work is based on a literature study done with credible electronic sources and industry facts, a number of manual calculations and results from the program FEM design. Result: The result was, as expected that the coupling beam failed to resist the loads from 22 storeys, but unexpectedly it could resist the loads from 13 storeys. Conclusions: The conclusion is that there are ways to have a satisfying section on 22 storeys by steel reinforcement or change the strength of the timber lamina. The section on the coupling beam from the report manage to hold for 13 storeys with the chosen parameters.

Purpose: This study aims to assess the three cultural historical buildings located in the municipality of Strängnäs, that doesn’t meet the accessibility requirements currently.  Therefore, the aim is to suggest solutions for each three buildings that could be useful to different authorities in the future. The focus is on wheelchair users using the buildings with the help of technical installations such as ramp, elevators, and accessible doors. The study will be based on the social-, historical-, and aesthetic aspect as well as the safety risk. Method: The method for this study is based on a literature study, and a case study, alongside with reference objects which will be the inspiration for our results. The literature study is based on fact-gathering from books and the internet which provides the study with information on cultural historical buildings, laws and regulations concerning the private buildings, cultural values, and with various safety risks. While the reference objects inspired our proposals for the measures, the case study was used to gather information in form of an interview, site visits, and communal document analysis. Results: The result of thisstudy provides measures for each of the three studied objects. Changes made to the first building, Hospitalsgatan 15, focuses on the side entrance with a ground slope pointing down towards it. Thereby the following indoor changes presents threshold ramp, and a stairlift. For the secondary building, Långgatan 9 E-F, there was suggestions made such as using an outer ramp with an idle plan. There should also be an indoor loose ramp, and a stairlift. The third building, Kyrkogatan 13, had suggestions by installing an outdoor platform lift with an adjusted idle plan in front of the outer stairs and threshold ramp. In comparison to the first mentioned building, the focus for the last two buildings were on the main entrance. All these measures were considered to reach an accessibility in cultural historical building while also keeping in mind the cultural value of the building and its safety risks. Conclusions: The study concludes that the social-, historical-, and aesthetic aspect as well as the safety risk works a crucial role in shaping the proposed solutions for the three buildings and contributes to the accessibility improvements. By adopting appropriate technical installations and considering the cultural significance of these structures, accessibility in cultural historical buildings can be achieved effectively. 

Today, there is a growing interest in developing energy efficient buildings since it is estimated that buildings account for about 40% of the total primary energy consumption in the world. In relation to existing buildings, energy efficiency retrofits have become an important opportunity to upgrade the energy performance of commercial, public and residential buildings that may reduce the energy consumption, demand and cost. In this paper we cover the energy efficiency deep retrofit process that has been carried out for Nottingham Playhouse theatre building for the aim of enhancing its environmental performance and analysing the energy efficiency gained after implementing certain proposed modifications. It is a nationally protected historic building, listed as Grade II∗ on The National Heritage List for England (NHLE). The building has had insulation enhancement, doors modifications, solar energy installations, energy-saving lights, in addition to improved heating and air conditioning system. The paper presents a novel methodology; and its results indicate significant improvements in the building's energy performance which is demonstrated using infrared thermographic images and data logger sensors where significant energy savings to the building's thermal performance are obtained. The energy saving measures have been completed while maintaining the heritage building's general appearance and architectural features, which have received a Commendation Certificate from The Nottingham Civic Society for this achievement.

SAMMANFATTNING

Datum: 2 juni 2024

Nivå: Examensarbete i produkt- och processutveckling, avancerad nivå, 30 hp

Institution: Akademin för Innovation, Design och Teknik, IDT, Mälardalens universitet 

Författare: Raiman Darman, 25 april 2000, Jasmin Alhaj, 12 mars 1998

Titel: Förbättra materialflödet genom Just-in-time

Handledare: Ola Wassenius & Oliver Söderlund, ABB Robotics, Mats Ahlskog, Mälardalens Universitet

Nyckelord:  Materialflöde, Just-in-time, Lean production, lagerhanteringssystem

Syfte: Undersöka hur Just-in-time-principer kan tillämpas för att förbättra det interna materialflödet och att identifiera nödvändiga funktioner i lagringshanteringssystemet för att stödja Just-in-time. 

Frågeställningar:

F1: Hur kan materialflödet i produktionssystemen förbättras genom att implementera Just-in-time?

F2: Vilken typ av funktionalitet behövs i lagerhanteringssystemet för att stödja Just-in-time?

Metod: Denna studie använder kvalitativ forskning och en abduktiv metod för att uppnå sina mål. Datainsamlingen kategoriseras i sekundär forskning, med en genomgång av befintlig litteratur, och primär forskning, som inkluderar en fallstudie genomförd genom intervjuer och observationer. Både semistrukturerade och ostrukturerade intervjuer används med caseföretaget och benchmarkingorganisationen. Användningen av benchmarking gör det möjligt att jämföra organisatoriska metoder, utmaningar och resultat, vilket hjälper till att identifiera områden för förbättringar och få insikter i effektiva strategier.

Slutsats: Genom att ta itu med den första forskningsfrågan kan materialflödet förbättras genom att gå över till ett pull-baserat system och implementera koncept som stormarknader och point-of-use. Dessutom är det avgörande att integrera automatiserade system för att spåra vagnens tillgänglighet och upprätta tydliga protokoll för standardiserade arbetsprocedurer. Kommunikation i realtid och koordinering mellan avdelningar, underlättat av avancerade lösningar som skärmar i realtid, är också sätt att förbättra materialflödet. För att ta itu med den andra forskningsfrågan är det viktigt att integrera det interna WMS med SAP ERP-programvaran, åtgärda kommunikationsluckor, tillhandahålla omfattande användarutbildning och support, effektivisera uppgiftssekvenseringen och genomföra regelbundna systemuppdateringar och underhåll.

 The premise of this project was to investigate as well as compare the obstacles and challenges that occur during the application of the systemic fire safety work on two building phases for schools i.e., the construction phase and the management phase. Furthermore, the study emphasizes the organization structure that implements the application of the fire safety work as well as finding solutions for the identified obstacles. The main methods used to achieve the objective of this study was literature studies in the form of jurisdiction, articles and rapports related to the application of fire safety work, interviews done with the work managements at the construction site and staff members from the school as well site visitation where observation of the locations were done and lastly document analyses. Result: The results from the study have shown that challenges were identified in the application of the systematic fire safety work in both buildings phases. From the construction site the obstacles found was due to unclear instruction and duties towards the workers as well as lack of knowledge and attitude from the workers. Furthermore, lack of resources and ability to plan ahead was identified which were one of the main problems that hindered the application of the fire safety work probably. The main results from the investigation of the school have shown students lack knowledge of intended fire consequences as well as no routines for control of new staff member’s ability to use fire extinguishing equipment.  In conclusion the obstacles that occurred during the construction phase were much more than the ones that occurred during the management phase. Some of the rulings and routines from the management phase can be applied for the construction phase to minimize some the obstacles that occurred within that phase. The construction phase must be better at applying the resources needed, planning ahead of time as well as giving more detailed instruction and duties to the workers and educating them. The management phase must better the student’s knowledge of the consequences of arson as well as putting forward routines for visitors and control of new staff member’s ability to use fire safety.     

Abstract 

Purpose: The purpose of the degree project is to examine how the development within the planning process has been over the past thirty years and also to highlight challenges and the shortcomings that arose in the last 30 years. Through streamlining, minimizing costs and specifying the design leads to further development and simplicity in the planning process. Method: The method in the degree project began with a literature study where a theoretical frame of reference regarding the planning process is presented to expand the knowledge of the subject. Subsequently, a qualitative study was conducted in the form of interviews with experienced individuals in the construction industry. With the literature studies and interviews as a basis, practical application was also carried out in the form of a model study where the functionality of different software was considered. Results: The results of the study present a summation of the interviews conducted. Digital development has facilitated with calculation programs or drawings that are simpler than before, and easier to edit with the help of digitization, but it has also resulted in poor communication, poorer connection and less collaboration because of this digital development. Furthermore, these problems have led to several errors in the projects. Another important problem that is noticed in the work is to cut off the projects in smaller moments that always create confusion and shortcomings. The stage shifts in the projects damage two major factors which are time and cost. After a summer of the interviews conducted, the data collected from the literature study were analyzed and linked. The analysis led to a proposal for improvement which is presented in the results of the work. Conclusions: Regarding the results of the study conducted in this degree project, plenty of conclusions are drawn on how the planning process have developed over the past 30 years, such as where in the planning process there are shortcomings, what development opportunities there are and what their potential consequences are.

Abstract 

Purpose: The purpose of this study was to examine the energy savings by replacing windows from existing 2-glazed windows to a new 3-glazed windows for a specific apartment in a specific apartment building in Botkyrka. In the major renovation project, no consideration was given to windows which are an important part of the building in terms of energy. Method: The method was to study the home and the associated floor plan was carried out to get an idea of the different orientation of the windows, but also to perform measurements. It formed the basis for the energy calculations that were made to analyse the energy use for the need of heating. And with that calculate the energy use for heating for each month for an entire year with the existing 2-glazed window and then compared with the energy use for the 3-glazed window. Results: The result shows an energy saving of 17%. That result is judged to be quite typical for apartment buildings from the million program. Conslusions: The conclusion that can be drawn from the work of this project is that the investment is profitable as it is compared with the annual savings for energy use for heating. It is the replacement of old windows that actually have a remaining life. In practice, it is difficult to do so with good profitability because a very large investment must "pay" a rather limited annual saving. 

Keywords: windows, energy efficiency, energy use and heating.

Emissions from oil wells and refineries are sources of air pollutants depending on their composition and amounts. The current study focuses on investigation and detecting of thermal anomalies and active hotspots in oil pipelines and refineries locations in Iraq, along with the spatial distribution of the ultraviolet aerosol (UV Aerosol) index. The goal is to assign the most polluted cities that can assist in evaluating the consequences of the air pollution on human and the environmental risk as well. We carried out the analysis of the products obtained from Terra/ MODIS data derived from channels 21 (4 µm) and 31 (11 µm), and the Sentinel-5P products/ Level 2 for the UV Aerosol index in the atmosphere, and found a number of active thermal signals in different geographic areas in Iraq, especially in southeastern and northeastern parts of the country, where the most of Iraq's petroleum resources are located there. The study shows a good correlation between the observed thermal anomalies and the UV emissions, and the results proved that the aerosol emission changes is significantly affected by emissions from oil wells and refineries. We also used fires reports obtained from the department of safety and fires in Basra to validate the outcomes and to investigate the final interpretation of the obtained results that were consist with the documented reports. As well as the results also shows a significant spatio-temporal variations in values of UV index among different parts of Iraq, and the larger amount of UV index has been seen in southern Iraq in Basra.

A construction project can be compared to a triathlon where the building process takes place in three stages and participants try to finish three sub processes as fast as possible to reach the goal. After the first stage is finished, the next begins to eventually jointly meet the milestones that are set on the road. There are many different players in a building process where everyone can have completely different tasks and work in completely different locations around the world. This require that the information between the different parties must be correct and shared to avoid delays and unnecessary costs.

Identifying, defining and structuring of information in the 3D-model reflects an organized approach where all information is available in the same location. The development in the construction industry has given the opportunity to let the information supply to be almost unlimited. BIM stands for Building Information Modeling, in design/construction models there is room for the construction industry to improve the efficiency and quality at much higher altitudes. Two systems that have grown during the BIM development is the BIP (Building Information Properties) and BSAB 2.0 (Bygg Samordning AB 2.0) which is designation and classification system in Sweden that aims to become the solution for a joint system for all construction companies. This would lead to that, information delivery becomes waterproof.

 This report is a study of how a common system can be applied to the accounting of the various construction companies to be similar and flawless. The lineup of solutions in the examination are solutions for the modeling software Tekla Structures. There is also an investigation of how the mapping of a complete system that allows the different parties in the construction process to use the same terms throughout the different sub processes.

Purpose: This study aims to investigate the profitability of various energy efficient measures and at the same time examine the energy savings for an old house from the 1970s.  Method: The methodology of this work is based on field measurements, observations, and document analysis. The calculations that were performed were monthly calculations performed in Excell. The data were then collected and analysed and provided the house's energy balance. The profitability of different measurements was then determined according to its payback period. Results: The house's estimated energy use for heating is about 22.1 MWh / year. With rock source heat pump, approximately 70% energy saving was achieved. With FTX-system, an energy saving of about 23% was achieved, while the replacement of windows & doors and additional insulation of exterior walls and attic achieved the same energy saving of approximately 14%. Economic analysis showed that installation of a ground source heat pump can be the most profitable alternative, according to the payback period and long-term analysis, which is an analysis over 40 years ahead. The results also showed that energy prices have a significant effect on the profitability, where doubled energy prices almost halved the payback period and at the same time tripled the economic profit after 40 years calculated with the prerequisites in the current study. Conclusions: For the current house, the replacement of windows & doors is recommended instead of the additional insulation because in associating with the replacement of windows & doors, the air leakage due to leaks can almost be halved, which would benefit a possible installation of FTX systems in the future. After doubling energy prices, some measures have given a return of more than 70%. Therefore, based on the data presented in this work, it is recommended to, in addition to the payback period, also make a long-term analysis to have a more stable basis when deciding what measures should be taken to reduce the purchased energy. This is because when comparing different energy saving investments, it is almost impossible to justify when considering only the payback period. It is also recommended that in an older one family houses with similar prerequisites, the bedrock heat pump should be installed first if there is no need for renovation. This is to maximize the energy savings and thus the financial gain.

In the development of society towards renewable energy sources, the target in Sweden is 100% energy supply from renewable energy sources by the year 2040. This requires increased energy production from renewable, but also energy optimization of existing buildings. The housing and service sector which includes households and the public services account for about 40 % of Sweden’s total energy use. It is estimated that preschools and schools have an area of 35 million m² which have an energy savings potentials of 0,7-1 TWh in the electricity consumption and 0,9 TWh in energy use for heating. With regard to energy optimization, it is not only interesting to investigate a buildings total energy use on an annual or monthly basis, but also on shorter time intervals such hourly energy use, because of the uneven energy production of some renewable energy sources such as solar and wind. The purpose of this work is to study the energy usage for some of Västerås preschools and schools, and on the basis of it propose some energy optimization actions. To achieve this a literature study has been carried out to get knowledge about how energy usage is at preschools and schools, as well as to gain insight into what actions are appropriate to perform and how they savings look like. Other than that four objects has been studied, two preschools and two schools, one of each kind were chosen amongst those with the highest energy usage among Västerås city’s preschools and schools and one of each kind amongst those with the lowest usage. The annual energy usage have been calculated and been compared to the actual usage, and the monthly and hourly energy usage for district heating have been studied as well as the electricity usage along the day for different periods. The studied periods and energy usage shows that the energy usage, both for the monthly and hourly,  for the district heating moves with regards to the outdoor temperature with some exceptions. As for the electricity usage it shows that the energy usage is even with some exceptions and there is a difference between different outdoor temperature intervals. Some conclusions could be drawn among others that the objects with higher energy usage where older buildings and the objects with lower energy usage where newer ones. There are some energy optimizations actions for the objects which would lower the energy consumption, both for district heating and electricity usage.

Purpose: The purpose of the work is to study the opportunities and/or challenges within recycling that exist from the aspects of economy, environment and technology. Likewise, to investigate potential opportunities to increase reuse and recycling regarding selected building materials. Also to investigate what opportunities exist to reuse and recycle waste materials in practice based on the aspects of economy and environment. Method: The method includes literature study, interviews, and case study of two demolition objects. The literature study identified Sweden's regulations regarding reuse, the reuse possibilities of building materials and the demolition process. Interviews with four different construction companies were conducted. Two items were analyzed to assess the potential economic and environmental benefits of increased reuse and recycling. Results: The results of the literature review and interviews identified financial challenges and opportunities for reuse, including lack of incentives, storage difficulties and time constraints. The possibilities consist of government initiatives, faster handling of recycled materials, early inventory before demolition and circular economy. Technical considerations include quality and warranty assurance, and CE-brand of recycled materials. Environmentally, recycling reduces emissions from the manufacture of new building materials, demolition waste and contributes to climate savings. Concrete, wood, gypsum, and mineral wool have great reuse potential, and if reuse is not possible, there are recycling options. The first object showed a financial saving of 140 238 SEK and a carbon dioxide saving of 2822,5 kg CO2-eq. The second object showed a financial saving of 921 120 SEK and a carbon dioxide saving of 681,9 tons CO2-eq. Conclusions: The conclusions indicate that the construction industry should increase its focus on recycling to achieve both economic and environmental benefits. To address technical challenges in assessing materials for reuse, a detailed technical inspection should be carried out for each specific case. There are also significant opportunities to increase both the reuse and recycling of building materials such as concrete, plaster, wood, and mineral wool, but a greater practical focus on this is needed within the construction industry. Based on the two case studies examined, it is concluded that by implementing strategies prioritizing reuse, both substantial economic and environmental gains can be achieved.

I dagsläget utvecklas ständigt nya metoder inom byggbranschen där hållbarheten i en konstruktion är av ytterst stor vikt. Betong är ett material som är mycket hållbart då det har en väldigt lång livslängd utan att det ger större skadeverkan. Detta resulterar i att materialet brukas allt mer i tillverkning av byggnationer.

Byggnadsteknik är i kontinuerlig utveckling vilket medför nya sätt att uppföra byggnader. Byggverksamhet går mer och mer åt att använda prefabricerade betongelement, en byggmetod som har blivit allt mer framgångsrik. Med denna metod kan byggtiden kortas ner väsentligt, byggprocessen blir även hälsosammare för omgivningen och är bättre ur olika arbetsmiljöaspekter.

Detta examensarbete skrevs i samarbete med AB Strängbetong som är ett av de största företagen i Sverige som använder sig av prefabricerade element. Företaget har ett koncept vid namn TempoDeck och har byggt ett parkeringshus med en förväntad livslängd på 50 år, det vill säga livslängdsklassen L50. Uppdraget som gavs var att kontrollera om denna byggnation klarade av kraven enligt normerna. Syftet var även att kunna utveckla en annan typ av fasadutformning genom att minska höjden på bjälklaget och balkar. Avgränsningen inom studien är att den endast gjorts på ett företag, AB Strängbetong, och fokuseras bara på parkeringshus med hänsyn till betongens täckskiktskrav.

Examensarbetet fullföljdes genom inläsning av litteratur, fallstudie såsom arkivanalys och beräkningar, med det norska programmet E-bjelke, samt handledning från AB Strängbetong.

Resultaten visade att den befintliga konstruktionen klarade av livslängdsklassen L50 med hänsyn till kraven. Det fanns även möjligheter till att estetiskt sätt ändra på parkeringshusets utseende, för att få den mer tilltalande. Det skulle dock vara mer ekonomiskt lönsamt att behålla utformningen som konceptet har till de framtida byggnationerna. 

Purpose: The purpose of this study is to identify problems and shortcomings in the process of building permits from the perspective of small house owners in Stockholm. The purpose of this study is also to present future improvements. Methods: The method for this study contains both literature study and a case study. The case study consisted of a digital survey and interviews with small house owners and with the municipality´s building permit department. The digital survey consisted of questions about previous experiences of the building permit process to then investigate where there are shortcomings and weaknesses. Results: The results gave a wider perspective of how the small house owners experience the building permit process and how the municipality works through challenges and improves the process. The digital survey showed that several were dissatisfied with the processing time and experienced it as a long period. The respondents also experienced it as a difficulty when it comes to submitting correct documents requested by the municipality and that there are high building permit fees. A concrete improvement measure is that Stockholm municipality clarifies the building permit process steps regarding processing times and other weaknesses that arise on the website. Conclusions: The conclusion of this work is that Stockholm municipality updates the website, so that applicants with less knowledge and experience regarding building permits can get a better idea and possibly follow the schedule and budget they planned for the project. To avoid damage caused by damp during the project, it is possible to undergo a so-called moisture safety design. Stockholm municipality can introduce more employees within the building permit department to be prepared for periods where there is high pressure in building permit matters.

Syfte: Syftet med denna studie är att jämföra lagkraven för Euro VI och CARB angående OBD certifieringen och därmed identifiera de utmaningar som kan uppstå i och med övergången från Euro VI klassificerade motorer till motorer som uppfyller kraven från CARB. Vidare syftar studien även till att undersöka hur dessa utmaningar påverkar organisationen.

Forskningsfråga: Vilka utmaningar uppstår för ett tillverkande företag vid utveckling av en OBD certifieringsprocess enligt lagkrav från CARB i jämförelse med Euro VI och hur påverkar dessa utmaningar organisationen?

Metod: Denna studie är av en kvalitativ karaktär som är baserad på en deduktiv forskningsmetod. Den teoretiska referensramen är uppdelat i två sektioner, vari den första är baserad på vetenskapliga artiklar och böcker och den andra från lagkrav. Empiriska data har samlats från intervjuer på fallstudieföretaget och metoden som har använts för att analysera materialet är tematisk analys.

Slutsats: Denna studie konkluderar att övergången från Euro VI till CARB lagkrav resulterar i omfattande förändringar för företagets OBD process och bringar organisationsförändringar inom företaget. Det kommer att finnas ett behov av att etablera nya processer och nya arbetssätt inom organisationen som kan leda till omfattande samordningsproblem som bör has i åtanke. Sammanfattningsvis är det av yttersta vikt att ta hänsyn till de organisationsförändringarna som förväntas uppstå i och med denna förändring och inte enbart fokusera på att implementera en ny process.

The examination has been performed at Bjerking AB, which is an architectural and engineering company. Bjerking AB has the ambition to be a member of Green Building.

The Green Building program developed in year 2005 by The European Commission, the program is an environmental system with the aim to improving energy efficiency within the sectors of non-residential buildings. The minimum requirements to participate the program are following: in new-built buildings the calculated energy consumption must be 25 % lower than the requirements in the BBR (Building regulations) and in refurbishment the reduction must be 25 % lower than before the optimization.

The aim of this study has been to examine and review the company Bjerking AB's energy efficiency work in the project of building the school/kindergarten S:ta Maria Alsike, where the goal is to get this building Green Building classed. A description of requirements to become a member of the Green Building has also accomplished in the thesis.

The methods performed in this study are literature review, searches on the Internet, studies on the project database for facts/values, calculation of energy consumption and interviews of members of the Green Building. 

The following issues have been dealt with in the report;

-          Did the building in the project manage the requirement to achieve an   energy consumption that is 25% lower than the requirements in BBR?

-          What technical measures/system was selected in the building?

-          What kind of cooperation was the project based on?

-          What is required for consultancy companies and real estate owners to become members of the Green Building?

The study of the project and calculation of estimated energy consumption in the building, give the result 47 kWh/m², year. This is 60 % lower than the requirements of BBR. The Green Building requirement is that the building's energy consumption should be at least 25% less than the requirements in BBR. The building fulfills this requirement by a significant margin. It can therefore be concluded that the technical solutions carried out in the building are energy efficient. The project consisted of the cooperation shape “partnering ", which can be assumed to be a good form of cooperation in order to achieve an energy efficient building. The consultancy company Bjerking AB and the landlord Knivsta Pastorat has the potential to become members of Green Building, as Green Building Endorser respective Green Building Partner.

Keywords: energy efficiency, requirements of BBR, technical systems, cooperation, consultancy companies, real estate owners, estimated energy consumption, partnering, Green Building Partner, Green Building Endorser.

Purpose: this degree project investigates the homeowner’s knowledge about their energy use and the impact of using visualisation tools such as thermal imaging to enhance public engagement in energy conservation in building. Additionally, the study try to increase the understanding of how people's behavior affects the energy use in buildings. The method: the presented study is based on 12 participants who own a single-family house in central Sweden. Participation in this study involved responding to two questionnaires and conducting a thermography inspection. A methodology developed to replace a standard thermography inspection with a DIY themography survey. The study identified and filled the gap in the literature, by allowing house owners to carry out the thermographing inspection of their own buildings, free of charge and by themselves. The participants took part of a developed educational material that helps in increasing energy awareness and includes explanations about how to interpret the thermal images and provides suggestions for possible conservation measures. Finally, a data analyse carried out based on questionnairs, thermal images and communications with the house owners. The results: cold bridges are the most common cause of heat loss in the inspected single-family houses. Householders with older buildings who have long term plan to live in their building are willing to implement measures, while participants with newer buildings do not consider it as necessary. The infrared camera has been an effective tool for visualization of heat loss and attract attention. Many participants are surprised over the results. Conclusion: the study confirms that the infrared camera is an effective tool for heat loss visualization and can be used for enhancing public engagement in energy conservation in building. Thanks to this visualization, Swedish homeowners have gained an increased interest in energy-efficient measures such as additional insulation, window replacement and sun protection. The study has increased the general awareness and knowledge regarding energy efficiency in buildings.

The report present a Master of Science in engineering work carried out at Mälardalen’s University, made this work within the research project METRO. The work is a part of the research project METRO. The focus of the METRO project is on the protection of underground rail mass transport systems e.g. tunnels and subways stations. The aim with this work was to determine if a concrete column placed close to the tracks at a subway station can withstand the effect and temperature of a fire in a burning train comparable to the effects and temperatures that showed at the full scale test carried out within the METRO project. A literature review was made previous to the following case study. The results from this show that the column is negligible affected by the fire.

Purpose: The purpose of this study is to examine the problems that occur due to moist in the workplace, as well as the measures that can be taken and which measures are most effective. The study will examine the material storage and how it is being handled in the workplace, exploring what directives the insurance companies have, so the insurance is valid. Lastly the study will compare the different measures based on an economic perspective, time perspective as well as material savings. Method: This study is based on a literature study and a case study. The case study is based on both an interview and a site visit. Information has been gathered from various sources such as books, previously made thesis and various governments websites. The case study for this thesis is conducted at Emausskolan in Västerås. Results: To ensure that the moisture management in the production is good a certified moisture expert is hired. Moisture on materials can be prevented by using just-in-time deliveries and the most optimal solution a weather protection. Directives from the insurance companies regarding moisture management at the workplace and what the entrepreneur is obligated to do after moisture damage has occurred. To minimize moisture and mold growth the workplace should be clean and dry. Self-monitoring and samples were carried out throughout the project to ensure that the work has been performed correctly. Conclusions: The conclusion for this thesis is that challenges for moisture depends on the weather, carelessness, and time pressed schedules. Solutions would be to have a tight climate shell, usage of weather protection and surface treatment on materials. Handling of materials is to a certain degree taken care of in terms of palletized and packaged but not always. 

The city park of Eskilstuna is under development. In 2013 the municipal of Eskilstuna kept a dialog with its citizens about the city park. They were given the opportunity to leave wishes and proposals about the development of the park and the larger part of the proposals recieved were wishes of a serving building. The question was where to place it and what the configuration of this building is going to look like? The purpose of this undertaking is to work out a place of gathering with high comfort and service for the park visitors along with making it fit for the parks character. The natural light and beautiful views are to take into consideration and usage when designing a building. Large glass sections facing open views are growing more common. When choosing the type of glass to be used for this one should take into consideration the noise of surrounding traffic. The question here is what type of glass to use specifically for the serving building in Eskilstuna city park, based on the technical aspects of sound and light? When searching the Swedish literature for scientific papers on architecture considering the designing of a restaurant building, we discovered an existing gap. This paper only covers the requirements on noise, material, fire and availability, function and the placement of the building, together with the architechtural properties. In this paper three areas regarding placement taken from the city parks developmental plan have been audited. The aspects audited is the choice for placement of light, surrounding vegetation, view, quarter, noise, traffic, availability and the logistics regarding pedestrians and vehicles. Areas are named A, B and C. Area C was chosen as the most suitable as the traffic surrounding is most distant there. Area C also possesses a beautiful view, it’s located at the centre of the park and surrounding vegetation provides a light shade. The configuration of the building is made with support from Swedish literature regarding the architechtural aspects of alignment, movement, envelopment, light and areal organization. This is presented in the form of drawings and explanations. The glass chosen for the restaurant building is based on a comparison of several audited types of glass. The chosen glass, named Modell 1, have good and suiting properties regarding noise reduction, transmission, reflection and U-value and is therefore considered to hold a higher performance in comparison to the other types of audited glass. 

En samverkanspelare drar nytta av interaktionen mellan det omslutande stålröret och profilens betongkärna för att därav erhålla en ökad lastkapacitet. För att förstå beteendet och effekterna av interaktionen mellan stål och betong är det viktigt att förstå de enskilda materialens beteende. Betongens huvudsakliga uppgift i en samverkanspelare är att ta upp tryckkrafter medan stålets främsta uppgift är att motverka momentpåkänning och uppta dragkrafter. I normal rumstemperatur samverkar stål och betong för att bära den aktuella lasten.

Samverkanspelaren har stor potential med avseende på lastkapacitet. Nedan tas några av de förväntade positiva effekterna av interaktionen mellan stål och betong upp:

• Förekomsten av buckling för stålet försenas samtidigt som den försämrade bärförmågan efter lokal buckling uppstått dämpas, beroende på betongkärnans återhållande effekt.
• Förhindrar spjälkning och hållfasthetsnedsättningen för betongen blir inte lika drastisk.
• Ökad tryckhållfasthet och deformations kapacitet, speciellt för grövre tvärsnitt.

Vid ett brandscenario utsätts pelaren för en temperaturhöjning. Värmeöverföringen från brandgaserna till pelaren sker främst genom strålnings- och konvektionsvärme. Lastkapaciteten för pelarens ingående material kommer att reduceras till följd av denna värmeökning. Storleken för reduceringen beror på hur hög temperatur materialen utsätts för, där en högre temperatur medför en kraftigare reducering. För den betongfyllda stålprofilen kommer således det omkringliggande stålet att fort bli mycket varmt medan betongkärnan erhåller en trögare temperaturökning. I brandfallets initialskede expanderar stålet hastigare än betongen, vilket medför att stålet då i princip bär hela den aktuella lasten. Efter en tid förmår inte stålet längre att vara lastbärare och betongkärnan bär då istället lasten. Pelarens slutliga kollaps sker först då betongkärnan slutligen inte förmår belastningen.

En jämförande teoretisk undersökning av samverkans-, betong- och stålpelare under termisk påverkan genomfördes i detta arbete. Beräkningsgången följer de dimensioneringsregler som finns för respektive material i Eurocodes. Kapacitetsberäkningar är gjorda för både normal rumstemperatur likväl som för brandutsatthet.

För analys och bestämning av pelartvärsnittens temperaturprofil vid de olika tidsstegen 30, 60 och 90 minuter användes ett nominellt brandförlopp. Tvärsnittens temperaturhistoria användes sedan för att reducera de mekaniska egenskaperna som funktion av temperaturen.Undersökningen konstaterade att samverkans- och betongpelarens kapacitet vid 60 minuters brandpåverkan var tillräcklig. Hand- och datorberäkningar påvisade nästintill likvärdig lastkapacitet vid termisk påverkan och normaltemperatur.

The main concern of this licentiate thesis is to discuss how built space is used for communication in the manufacturing industry, from a visual communication perspective. The thesis presents and develops the notion of 'communication space' and presents a model to describe the relation between different factors in the communication space.

In a multiple case study, six different cases from the manufacturing industry are described and analyzed to highlight how built space is used for communication in a lean production context. Research results on how built spaces such as improvement places, meeting places and a development workshop affect improvement processes and communication are presented. What the studied improvement areas, meeting places and workshop can be said to communicate about the improvement processes is analyzed.

The research results show that the built spaces in manufacturing industry are used for communication on two levels, both as places for interaction between employees and as a part of a communication process. The study also shows a relation between architecture from a specific time and the relation to the improvement work in the industrial context. How the results can be used to facilitate communication in the built spaces used for improvement processes in manufacturing industry is suggested in the thesis.

Purpose: This study aimed to conduct a case study, with focus on work environment, economy and technical implementation, to determinate the difference if a prefabricated bridge had been constructed instead of a cast-in-situ bridge. Method: The study is based on a literature study and a case study. The case study is mainly based on interviews, data collection and attendance at the construction site. Results: The result of this study was that it is possible to combine both on-site and prefabricated elements, not as requested but as a beam frame bridge. The best option would be to cast the foundation on site and use prefabricate beams and retaining walls.  Prefabricated elements are constructed in a more controlled environment and therefore it is easier to fulfil a better work environment. If the actual bridge were to be made with prefabricated elements instead of layed on-site, the price would not differ too much. Conclusions: The big difference between prefabricated elements and on-site concrete is the labour and the material cost for the formwork. The biggest risk, regarding work environment from both perspectives, was identified as working at heights and vehicle in movement.

In recent years, market competitiveness exerts more pressure on process industries to increase their number of products, reduce order sizes and shorten delivery lead time. This causes an expansion of order enquiries from customers, which leads to an insufficient use of scheduling and planning systems to meet these changes. This force process industries to adopt other tools, such as Discrete Event Simulation for supporting their strategic decisions to align with these operational changes.

The objective of this thesis is to understand how Discrete Event Simulation supports strategic decisions prior to the implementation of operational changes in process industries. Therefore, a case study in the pharmaceutical industry was conducted at AstraZeneca, Södertälje. Discrete Event Simulation was used as a tool to support the strategic decision of implementing the Product Wheel technique as an operational change. Simultaneously, a theoretical review was carried out to investigate types of strategic decisions which can be supported by Discrete Event Simulation use in process industries. Then, contributions and challenges of Discrete Event Simulation use for supporting strategic decisions for operational changes were clarified. 

The empirical results indicate the importance of Discrete Event Simulation in supporting deliverability as a competitive priority to AstraZeneca, followed by flexibility and cost as second and third competitive priorities. The analysis also identified the contribution of Discrete Event Simulation in supporting long-term decisions in the company by providing analytical solutions in different scenarios, dynamic visualization and increased knowledge about the simulated operational change. Additionally, two main challenges in the use of Discrete Event Simulation for supporting strategic decision are identified. First, Discrete Event Simulation was not suitable for supporting all kinds of competitive priorities such as quality, environment and innovation. Second, the direction of the communication between the Discrete Event Simulation use and the strategic decisions differs.   

A framework is developed to facilitate the use of Discrete Event Simulation for supporting strategic decisions prior to implementing the Product Wheel technique as an operational change. This framework provides a guideline to identify the range of contributions from Discrete Event Simulation use for supporting different types of competitive priorities prior to the implementation of the Product Wheel method. Generally, Discrete Event Simulation could be a useful tool for supporting deliverability, cost and flexibility by implementing the Product Wheel technique, while it has a limited capability when dealing with other strategic decisions such as quality, innovation and environment.

This paper investigates problem areas related to energy efficiency implementation in Swedish multifamily buildings. The paper first presents a generic list of (theoretical) problem areas identified through a literature survey. Using a qualitative approach, the paper also investigates if the problem areas identified in the literature also have an impact on the Swedish building sector. Results from the interview study reveal a strong coherence between problem areas in the literature and those expressed by the interviewees. However, this paper identifies seven novel challenges that cannot be derived from the list of barriers in the literature. Moreover, results reveal that as many as 12 problem areas have their origin in national factors such as agreement structures, incentive schemes, and cost calculation methods.

This master thesis is performed on behalf of Volvo Group Trucks Operations Logistics Services in Eskilstuna, which is also the final part of the Master in Engineering program – Innovation, production and logistics at Mälardalen University.

Logistics Services central warehouse in Eskilstuna ensures that parts are available all over the world, material is transported to the production facilities, packaging is available and vehicles are distributed to the dealers. The current need is to reduce costs and improve the production process at the Inbound department. The aim of this project has been to analyze the current flow of materials and tied-up capital in the inbound flow and give improvement suggestions on reducing lead times and the tied-up capital, as well as give suggestions on common performance metrics for all the sub departments at Inbound.

The report is based on theoretical and empirical study, where the theory concerns the topics; logistics, lean philosophy and supply chain management. The empirical study was carried out by data collection through time measurements in the plant and by BEAT-report, observations and discussions with the operators, and interviews with production managers and process developers. The collected data was analyzed and the products in the flow were divided into groups, where the inbound material flow was mapped by the VSM tool. Product groups were analyzed by amount of received material reports, quantity, value and lead time, and the product groups that tied the highest value were defined as well as where in the flow the value was located. For each sub department calculations on production capacity and utilization were performed to analyze the current state and be able to compare the departments with each other. The interviews contributed with knowledge to create a reliable and valid SWOT analysis for each sub department at Inbound, where common factors could be defined concerning deviations, performance metrics and other hidden problems, but also opportunities.

Finally, in this report the current state in the Inbound department has been analyzed. Products have been categorized into groups and the materials flow mapped. It has been defined where in the flow and how much value that is tied up, and by which product groups. Hidden problems and deviations have been brought up to surface. Improvement suggestions have been given concerning decreasing of lead times and the tied up value, and also suggestions on common performance metrics for all the sub departments have been given.

Detta examensarbete avser ett pilotprojekt utfört mellan månaderna januari och maj, 2015 på det karakteristiska legoföretaget Södergrens Br. Metallindustri AB i Eskilstuna. Pilotprojektets syfte är att redogöra hur Södergrens men framförallt andra karakteristiska legoföretag kan implementera och tillämpa förbättringsmetoden DMAIC, med målsättning att förbättra den allmänna kvalitén och således också nedbringa kvalitetsbristkostnader. För att göra detta genomförbart har man infört ett förbättringsprojekt på ett anpassat studieobjekt. Studieobjektet som utretts avser hanteringen av fixturer, mätdon och mätrum på Södergrens Br. Metallindustri. Datainsamlingen under pilotprojektet har utförts med hjälp av intervjuer, observationer, benchmarking och ett antal kvalitetsverktyg kopplade till DMAIC-metoden.

Slutresultatet visar att Södergrens Br. Metallindustri och därav även andra legoföretag kan dra nytta av att implementera och tillämpa DMAIC för blivande förbättringsprojekt på företagen. Det som framförts under pilotprojektets gång stämmer överens med teori om implementering av DMAIC och anpassningsbara kvalitetsverktyg. Det som markant påverkar effektiviteten av förbättringsprojektet och således även anses vara mycket viktigt, är att utvald förbättringsgrupp har eller tilldelas rätt kunskap av DMAIC-metoden och allt därom. För att även försäkra att man väljer rätt förbättringsprojekt och få en sammankoppling mellan förbättringsgruppen är det viktigt att tillsammans formulera fram ett projektkontrakt med tillhörande mål och krav.

Introduction: An investigation about how ties are designed for accidental loads according to Eurocode 1: SS-EN 1991-1-7 and Eurocode 2: SS-EN 1992-1-1, with attention on ESK 11, the Application of the European construction standards by the National Board of Housing. Eurocodes are the European standard for how buildings should be constructed. They are treated to some extent in the EKS, who makes adaption to the rules with consideration to the Swedish environment. And by the National Board of Housing, EKS becomes a norm in Sweden and is applied to construction. Accidental loads can be diminished by a minimum to the largest of Eurocode 1 and 2 with changes of EKS. Purpose: To investigate and clarify how ties for accidental loads are designed and arranged. Method: For the relevancy of this thesis a major focus is to study Eurocode 1 and 2, side by side with EKS 11. These will be compared to real construction drawings provided by Kadesjös Ingenjörsbyrå AB and additionally be confirmed with manual calculations for a fictitious building made by the authors. Results: The results present proposals for how different ties under tension should be defined, designed, and placed. Together with an overall solution for designs, and calculations of a fictitious building that meets the same requirements as for the buildings in the study objects. Whether there are any conflicts between regulating documents will also be brought up. Conclusion: In the event of accidental loads ties shall act as a measure to prevent the progressive race caused by an accident, by strengthening the connections between different structural parts. The ties that are studied in this thesis are categorized by either of two definitions, direct ties, and indirect ties. Where direct ties are only used for the purpose to function as a tie for accidental loads, and where indirect ties could be used by already existing reinforcement. The investigation shows that most of the ties that are required for accidental loads can be designed with indirect ties, that not all of them are necessary and that the required dimensions are low.

The handling of construction logistics around building materials has long been a major problem that has been noticed since 1960. The handling of construction logistics is important as they have a major impact on costs and customer service. There is a lot of work on a small area of ​​building a skyscraper that includes many risky elements and factors that affect production speed and schedule.

In Gothenburg, a skyscraper will emerge from the city, with its 245m and 73 floors, which will be a building like no other in the country. A complex comprehensive construction project which leads to a complex logistics solution with good planning of the logistics flow.

The purpose of this degree project is to map the management of the construction logistics and to review how the planning of the factors that will guide the logistics of the construction project will look.

In order to respond to the purpose of the study, a case study has been made based on interviews of three key people within the Karlatornet project. Site visits have been made to get a real picture of the Karlatornet project. During the visit, documents and pictures were received regarding the logistics of the project.

The result shows that careful and early planning of the construction logistics reduces waste and increases the flow efficiency for a construction project like Karlatornet. Gathering enough knowledge from similar projects around the world has led Serneke to produce a logistics appendix that serves as a functional description for how logistics should be handled at Karlatornet. This logistics appendix acts as a contract document where all parties involved in the project must work according to the logistics appendix, which is a standardized working method for logistics management.

Through various tools such as Myloc, BIM and LEAN's production management philosophy, the project has been able to achieve an efficient logistic solution that fits Karlatornet.

The objective of most rural electrification programs in the developing world is to bring about socioeconomicdevelopment to households. Governments have put in place a number of measures to achievethis goal. Previous studies on rural electrification programs in developing countries show that solar homesystems and mini-grid systems are the dominant technologies. Assessments of a pilot hybrid mini-gridproject at Lucingweni village have concluded that mini-grid projects are not feasible due to high electricityproduction costs. As a result efforts toward rural electrification have been focused on the solar homesystem. Nevertheless, previous studies of the South African solar home system program have shown thatthe development objectives of the program are yet to be met more than a decade after commissioning.Therefore, this study investigates the viability of a hybrid mini-grid as a solution for rural developmentin South Africa. Investigations were based on Lucingweni and Thlatlaganya, two rural Villages where themini-grid and solar home system have been introduced. The mini-grid systems were designed taking intoconsideration available natural resources and existing load profiles. The results show that a village of 300households needs about 2.4 kW h/household/day of electricity to initiate and sustain income generatingactivities and that the solar home system is not capable of supporting this level of demand. We also showthat in locations with hydro resources, a hybrid mini-grid system has the most potential for meeting theenergy needs of the households in a cost effective manner. The assessment shows that with adequateplanning and optimization of available resources, the cost of electricity production can be reduced.

Abstract

Work to develop the Eurocodes started in 1975 by the European Commission adopted a program to eliminate trade barriers within the construction area. The goal was to create common European design standards that would replace the member countries' own rules. Eurocodes will replace The National Board of Housing Building and Planning, National Rail, The National Road Administration and other agencies' calculation rules for the buildings structures. The transition to the use of Eurocodes looks like this:

• Eurocodes set to Swedish standards  between 2002 – 2007
• They can be used parallel with national standards 2006 - 2009
• The total transition is at the end of 2010/2011.

Right now is going on a lot of work for replacement of the existing standards to Eurocodes.  The transition to the new calculations` standards, many construction companies and consulting firms facing a big changes and competitions. Because of the preparations for the transition, I was commissioned by my examiners to carry out my thesis in the design of foundations by using Eurocodes. The report addresses, the design off foundations according to Eurocode SS - EN1997.

The purpose of this thesis is to point out the main changes occurring in the design of foundations of the implementation of Eurocode SS - EN1997 and the practical and financial implications that will have on the design and performing. The objective of this thesis is that it should be a basis for design and calculation of foundation.

The method of work has been to study existing and future conditions for the design of foundations, literature review and Internet searches have been made to gather information about Eurocodes, and collection of materials from my external supervisor has been made.

Below are a number of questions that will be answered in report:

• What is the Eurocode SS - EN1997?
• What are the advantages and disadvantages of Eurocodes?
• What changes will occur in the design process?
• What are the practical and economic consequences of Eurocodes for large and small companies?

Result of this work is that it can be used as a basis for design of foundation. In the capital 5 to 8 have been described the fundamental aspects of the design of foundations. Capital 9 relate to the design of various types of ground structures such as the Spread Foundation, Pile foundation and Retaining structures.