The flexural behavior of a light-weight wood-based composite system was studied through destructive experiments. The composite panel system consisted of profiled dimensional lumber, which makes up the surface layers, and 1"-thick boards running across the surface layers. Considering the changes in cross-sections along the panel due to the presence of the embedded boards, classical theories such as the Euler-Bernoulli beam and Kirchhoff-Love plate could not be implemented. Instead, the deflections and maximum failure loads of the composite system under full- and short-span bending tests were measured during their destructive bending testing, and were compared against the mechanical properties of the conventional three-ply CLT panel with the same thickness as the panel with embedded cross-laminations. According to maximum failure loads and deflections, it was concluded that full-span panels with embedded cross-laminations exhibited higher strength and stiffness, whereas short-span panels exhibited higher strength and lower stiffness properties compared to conventional CLT panels.

Thermal stresses can arise in glass used in architectonic realisations in buildings as a result of solar irradiation:  that is, sunlight.  The magnitude of these thermal stresses depends on the temperature conditions in the glass in terms of the temperature differences between warm and cold areas.  The work described here has verified the existence and distribution of thermal stresses in glass, both theoretically and experimentally, in a load-bearing element made of glass and wood, when exposed to incident solar radiation and various degrees of shading.  The finite element method was used in order to simulate the temperature distribution in the glass, together with the resulting associated thermal stresses.  Parts of these model results were then compared with results and data from experimental investigations in a solar simulator.  The experimental trials were carried out on a plain glass sheet and on a wood-framed glass sheet.  This frame assembly saw the glass fitted in a wooden frame such that its edge was flush with the edges of the frame and therefore freely exposed to the surroundings.  Two different grades of glass were analysed in the theoretical modelling and used in the experimental solar exposure:  a clear glass, with a low absorption coefficient, and a tinted glass having a relatively high absorption coefficient.  The experimental part of the work included two different finishes to the glass edge:  as-cut, with no further attention, and cut and smoothed.  The results from the finite element method calculations agree relatively well with the experimental results.  When simulating the temperature values and distributions, the value of the coefficient of heat transfer is an important factor in determining the results.  The coefficient can be given either a constant value, taken from a standard, or a calculated value that varies depending on the surface temperature and ambient temperature at every instant.  For the clear glass with a low coefficient of absorption, the calculated temperatures did not differ significantly depending on which method had been used to provide a value for the coefficient of heat transfer.  However, for the glass with a high coefficient of absorption, and when exposed to high solar intensity, a calculated value of coefficient of heat transfer should be used in order to arrive at relevant values of surface temperatures and stresses.  Thermal tensile stresses have more effect on the total stress level than have stresses arising from typical in-service vertical loads.

I Sverige finns det ett stort antal ekonomibyggnader som är byggda med traditionell timmermansteknik. Merparten är upprättade mellan 1870 – 1940, ofta byggda i egen regi utan att laster beaktats eller dimensioneringsberäkningar utförts. I dagsläget finns det standarder som beskriver hur en lämplig dimensionering av moderna konstruktioner och förband bör utföras, men inga riktlinjer för hur äldre träförband kan kontrolleras.   Målet med examensarbetet är att med utgångpunkt från Eurokoder göra en approximativ hållfasthetsberäkning av de förband som återfinns i takstolen i ett studerat objekt, med syfte att avgöra huruvida Eurokoder är lämpliga som beräkningsmedel för äldre träförband.   Resultatet visar att vissa förband i hög grad är beroende av att krafter kan tas upp via friktion, vilket är något som inte beaktas i Eurokoder. Dessutom innebär de säkerhetsfaktorer som Eurokoder medför att en del förband anses underdimensionerade. / There is a large amount of outbuildings built with traditional cogging technique in Sweden. Most of them were built in 1870-1940, often without proper dimensioning. Today there are standards describing how to properly dimension modern structures and joints, but there are no standards describing how to verify the strength of older wooden joints.   The objective of the thesis is to approximate the strength of the joints found in the truss of an actual outbuilding by using Eurocodes, with the purpose to determine whether the Eurocodes are suitable as a calculation tool for older wooden joints.   The result shows that curtain joints are highly dependent on forces of friction to counteract the strain of the joints, which is something that is not taken in to account in any of the Eurocodes. Additionally some joints are considered underdimensioned do to the safety factors the Eurocodes entails.

La escuela de la cosmovisión Ashaninka surge por una necesidad de la comunidad el Milagro para recuperar el conocimiento ancestral que se está perdiendo, como la textilería, la recolección y la curandería; donde la educación tradicional no recopila la importancia de estos saberes. Asimismo, el proyecto está diseñado para que la misma comunidad pueda construirlo y adaptarlo a sus necesidades. El proyecto surge de la cosmovisión ashaninka, donde todas las partes pertenecen a un todo y actúan juntas de una manera armoniosa creando sistemas espaciales, en donde las actividades ancestales convergen con las educativas; sistemas ambientales, en donde se aprovechan las lluvias, rayos solares, los vientos y compost; y sistemas constructivos, en la cual se desarrolla una estructura modular flexible y adaptable para los diversos usos de la escuela. De esta manera, mejorar las técnicas constructivas tradicionales y los materiales como la madera y fibras vegetales. Con ello propiciar una construir rápida y sencilla tomando en cuenta expresiones materiales y espaciales para estimular una cohesión educativa ancestral. / The school of the Ashaninka Cosmovision arises from a need of the community “El Milagro” to recover the ancestral knowledge that is being lost, such as textiles, gathering and healing; where traditional education does not gather the importance of this knowledge. Also, the project is designed so that the community can build it and adapt it to their needs. The project arises from the Ashaninka Cosmovision, where all the parts belong to a whole unit and act together in a harmonious way creating spatial systems, where the ancestral activities converge with the educational ones; environmental systems, where rain, solar rays, winds and compost are used; and construction systems, in which a flexible and adaptable modular structure is developed for the different uses of the school. In this way, improve traditional construction techniques and materials such as wood and natural fibers. Therefore, design promote a quick and simple construction taking into account material and spatial expressions to stimulate ancestral educational cohesion. / Tesis

During the past years, the usage of wood as construction material in multistory applications has increased. In Germany and Sweden, various activities have been, and are about to be performed, to accentuate and improve the position of wooden multistory houses. In line with that, this thesis tries to contribute to the understanding of how consumers perceive durable products; in the contextual frame of how German and Swedish consumers perceive wooden multistory houses. It was hypothesized that consumers’ perceptions on durable products differ, depending on their age, income, national and within-country habitation. Based on the Means-End Chain Theory, the Association Pattern Technique has been further developed to collect and analyze data for two samples. In Germany and Sweden, 31 respectively 34 laddering interviews have been carried out which formed the base for a survey-study in each country. Here, 229 surveys were received from German, and 503 from Swedish respondents. The results show that age, income, national and within-country habitation have significant impact on consumers’ perceptions of wooden multistory houses. Moreover, the extension of the Association Pattern Technique was validated. It allowed for additional data to be gathered, which can be regarded as rather important, since it appeared in the most dominant Means-End Chains of the respondents in both Germany and Sweden. This helps to understand consumers’ underlying reasons why one product is favoured over another.

Purpose: The purpose of this study was to investigate whether timber-concrete composite (TCC) floors made of a CLT-deck and casted concrete could be used as a method for increasing the use of wood as a building material. Method: The methods used in this degree project were a literature study, in which a number of laws of construction and different connector systems were studied, as well as an experiment consisting of bending tests on CLT-decks with casted concrete where SFS VB-screws were used as shear connectors. Results: The TCC-beams in the experiment behaved as expected and went to bending failure. The beams displayed an almost invisible slip between the materials despite the low composite action of 40,2 %. In addition, the beams had a higher bending stiffness on average than CLT-beams of the same height would have. Conclusions: Compared to floors made entirely of wood, TCC-floors with CLT add extra mass, stiffness, and better acoustic properties to the construction while maintaining a low floor height. The three main types of connectors used in TCC floors are mechanical, notched and glued-in connectors, where the latter two generates higher composite action and stiffness. Adhesive connection is another method with great potential, but there is still more research needed for this type of connection to be used.

Purpose: The report aims to contribute to sustainable social development. The survey aims to find out what municipalities 'work for sustainable construction looks like today and propose measures that can increase municipalities' construction of wood as a building material in the short term. The carbon dioxide neutrality of the wood justifies the investigation, which is directed to the situations where the municipality grants land for development and the cases where the municipality acts as a client. Method: The report is a qualitative work where selected survey methods are case studies, literature studies, document analysis and interviews. The literature collected consists of scientific articles. Interviewees were selected, partly from three municipalities where it was known that work was underway for increased wood construction, these are Växjö, Jönköping and Varberg municipality. Two more people were interviewed about the properties of the wood, they serve at RISE and Martinson's respectively. The documents analyzed are partly linked to the respective municipality, partly to municipal wood construction in general. Some of the people interviewed have been involved in creating some of the documents that have been analyzed. Findings: The report shows that municipalities' work towards ecological sustainability in society benefits from the design of a wooden building strategy. Establishing a deeper knowledge of wood as a building material internally in the municipal organization will make it easier for wood construction to be put into practice. Good contact with the business community regarding wood construction is an important factor in creating good cooperation and gaining greater knowledge in the field. The organization agrees is crucial in order for a commitment to increased wood construction to be fully realized. Municipalities can achieve increased wood construction by designing several incentives and means of power to use as a client and in the planning process when land is to be built by other actors. Implications: Designing a wooden building strategy lays a good foundation for a municipality's continued work on increasing wood construction within the municipality. Furthermore, the fact that the municipal organization further educates officials within the subject and clearly paves the way towards set goals gives good conditions for succeeding in the process. Connecting the business community through networks and collaborations creates important foundations for further work. Municipalities need to see the benefits with the legislative tools they possess and thus use them to steer towards sustainable construction.Limitations: All municipalities with a wooden building strategy are not included in the survey. More interviews with experienced municipal officials had contributed to an even more complete basis. Some of the documents were not finalized by the authors when they were analyzed for the report, which may mean that some information was not analyzed. The survey was conducted only at municipalities with a population of between 60,000 and 140,000 inhabitants. / Syfte: Rapporten syftar till att ge ett bidrag till hållbar samhällsutveckling. Undersökningen ämnar ta reda på hur kommuners arbete för hållbart byggande ser ut i dag och ge förslag på åtgärder som kan öka kommuners byggande med trä som byggmaterial på kort sikt. Träets koldioxidneutralitet motiverar undersökningen som riktar sig till de situationer då kommunen upplåter mark för bebyggelse och de fall då kommunen agerar beställare. Metod: Rapporten är ett kvalitativt arbete där valda undersökningsmetoder är fallstudie, litteraturstudier, dokumentanalys och intervjuer. Den litteratur som samlats in består av vetenskapliga artiklar. Intervjupersoner valdes, dels ifrån tre kommuner där det var känt att det pågick ett arbete för ett ökat träbyggande, dessa är Växjö, Jönköping och Varbergs kommun. Ytterligare två personer intervjuades kring träets egenskaper, de tjänstgör på RISE respektive Martinsons. Dokumenten som analyserats är dels kopplade till respektive kommun, dels till kommunal träbyggnation i allmänhet. Några av de personer som intervjuats har varit involverade i att skapa några av de dokument som analyserats. Resultat: Rapporten visar att kommuners arbete mot en ekologisk hållbarhet i samhället gynnas av att en träbyggnadsstrategi utformas. Att etablera en djupare kunskap om trä som byggmaterial internt i kommunorganisationen leder till att träbyggande bli lättare att omsätta till praktik. En god kontakt med näringslivet i fråga om träbyggande är en viktig faktor för att skapa ett gott samarbete och erhålla större kunskap på området. Att organisationen är enig är avgörande för att en satsning om ökat träbyggande ska kunna förverkligas full ut. Kommuner kan uppnå ett ökat träbyggande genom att utforma flertalet incitament och maktmedel att nyttja i egenskap av beställare och i planprocessen då mark ska bebyggas av andra aktörer.Konsekvenser: Att utforma en träbyggnadsstrategi lägger en god grund för en kommuns fortsatta arbete med att öka träbyggandet inom kommunen. Att kommunorganisationen därtill vidareutbildar tjänstemän inom ämnet och tydligt stakar ut vägen mot uppsatta mål ger goda förutsättningar att lyckas med processen. Att knyta näringslivet till sig genom nätverk och samarbeten skapar viktiga fundament för vidare arbete. Kommuner behöver se nyttan med de lagstiftade verktyg de besitter och därmed nyttja dem till att styra mot ett hållbart byggande. Begränsningar: Alla kommuner med träbyggnadsstrategi är inte med i undersökningen. Fler intervjuer med erfarna kommuntjänstemän hade bidragit till ett än mer fullödigt underlag. Några av dokumenten var inte färdigbearbetade av upphovsmännen då de analyserades för rapporten vilket kan betyda att viss information inte analyserats. Undersökningen utfördes enbart hos kommuner med ett invånarantal mellan 60 000 och 140 000.

Detta arbete är en uppgift som är mottagen från SNA Europe och genomförd under vårterminen 2018. SNA Europe är en europeisk tillverkare av framförallt handverktyg med huvudsaklig produktion i Europa med en internationell marknad. Syftet med arbetet är att förse SNA Europe med underlag i form av fakta, analyser och slutligen ett förslag på ett produktkoncept. Förslaget på produktkonceptet gäller en sk snabbvinkel, ett markerings- och mätverktyg baserat på Swansons Tools original Speed Square. Snabbvinkeln är mycket populär i USA men används inte i Europa, därför av intresse för SNA Europe. Arbetet planerades upp i fyra faser över en tio veckors period där faserna strukturerades upp i ingående underfaser. Det initiala arbetet har gått ut på att leta fakta om och analysera uppgiften för att kunna bygga en grund för en konceptframtagning. Då tillräcklig information erhållits påbörjades design- och utvecklingsarbetet av ett produktkoncept med en fastställd konceptdefinition. Slutligen efter CAD-modellering och prototypframtagning resulterade arbetet i en så gott som fullt färdigt produktkoncept som SNA Europe kan tillverka i egen fabrik. Framarbetat produktkoncept förverkligades i form av en slutgiltig prototyp tillverkad av SNA Europe. / This work is a task received from SNA Europe and completed during the spring term of 2018. SNA Europe is a European manufacturer of mainly hand tools with main production in Europe with an international market. The purpose of the work is to provide SNA Europe with a basis in the form of facts, analyses and finally a proposal for a product concept. The proposal for the product concept concerns a so-called rafter square, a marking and measurement tool based on Swansons Tools original Speed Square. The rafter square is very popular in the United States but is not used in Europe, therefore of interest to SNA Europe to make a own design. The work was planned in four phases over a ten week period, where the phases were structured into in-depth phases. The initial work has been to search for facts and analyse the task in order to build a foundation for a conceptualization. When sufficient information was obtained, the design and development work began with a product concept with a defined concept definition. Finally, after CAD modelling and prototype production, the work resulted in an almost complete product concept that SNA Europe can manufacture in its own factory. Developed product concepts were implemented in the form of a final prototype manufactured by SNA Europe.

I Sverige står bostadssektorn för mer än en tredjedel av landets energianvändning. Byggnader måste minska sin energianvändning för att således kunna uppfylla framtida lagkrav om maximal tillåten energianvändning, men också för att minska påverkan till global uppvärmning. Ytterligare en problematik som råder, däribland i Sverige, är bostadsbrist. Kommunala bostadsbolag står inför utmaningen att kunna bygga bostäder snabbt, billigt och miljövänligt för att minska bostadsbristen i landet. Ett sätt att studera två av tre hållbarhetsaspekter vid val av framtida bostadsbyggande är att utföra en livscykelanalys (LCA) och livscykelkostnadsanalys (LCC) kring de tilltänkta husen. LCA:er indikerar vilken miljöpåverkan en produkt förorsakar under dess livslängd. LCC:er avser att studera vilka kostnader produkter ger upphov till under en given analysperiod. Det svenska kommunala bostadsbolaget Stångåstaden AB står inför utmaningen kring bostadsbrist och vill bygga hållbara bostäder. Bostadsbolaget har önskat en jämförande LCA och LCC av två verkliga flerbostadshus som de genom ramavtal kan upphandla, detta är utgångspunkten för denna studie. Den ena byggnaden har stomme av betong, den andra har stomme av trä. Husen är tänkta att placeras i utkanten av Linköping, Sverige. Studien har valt att analysera miljöpåverkan från husens olika livscykelfaser samt kostnader över analysperioden 50 år. Utöver detta studeras även vilka energieffektiviseringsåtgärder (EEÅ) till byggnaderna som är optimala att genomföra för att öka den termiska prestandan hos huskonstruktionerna. Från litteraturen finns det relativt få studier som kombinerar både LCA och LCC för vanligt förekommande hustyper i städer. I dess standardfall påvisade resultatet från LCA:n att huset med betongkonstruktion hade något lägre påverkan i sex av sju studerade miljöpåverkanskategorier, jämfört med flerbostadshuset i trä. Resultatet skilde sig lite åt då annan typ av indata användes. Vad gäller kostnader under husens livslängd var huset i trä ungefär 20 % dyrare jämfört med huset med betongkonstruktion. Trots annan typ av indata var träkonstruktionen dyrare än betongkonstruktionen. Med en kalkylränta på 7,5 % var det inte lönsamt att genomföra EEÅ för husen, med halverad kalkylränta blev det dock lönsamt att tilläggsisolera krypgrunden i huset med trästomme. Fler studier behöver utföras för att generalla slutsatser ska kunna dras kring vilket konstruktionsmaterial som är mest hållbart. Denna studie baseras på två specifika fall. Samma resultat kan eventuellt inte förväntas för andra byggnader med stomme i betong och trä. / The residential sector accounts for more than a third of the energy use in Sweden. To reduce the energy use of buildings is a necessity in order to meet future regulationof maximum allowable energy, but also important to reduce the impact on global warming. Another complexity arising in Sweden is the shortage of accommodation. Municipal housing corporations face the challenge of constructing residences fast, cheap and with concern of environmental effects in order to reduce the shortage of accommodation. One way of assessing two of the three aspects of sustainability when looking at future construction of residential buildings is to carry out a Life Cycle Assessment (LCA) and a Life Cycle Cost Assessment (LCCA). An LCA can indicate what kind of environmental impact a product causes over its lifetime and the LCC allows for assessing what types of costs are associated with the product. For the municipal housing corporation Stångåstaden AB the shortage of accommodation is a reality and their mindset is sustainable construction of residences. This study was conducted upon request from Stångåstaden who wanted a comparative LCA and LCCA between two prefabricated multi-residential buildings that are available to them through a framework agreement. The first building has a concrete foundation and the second one is made of wood. The houses are planned to be placed at the outskirts of Linköping, Sweden. The focus of this study has been to comparatively assess the environmental impact from the different life cycle phases and the economic costs of the two buildings during a time period of 50 years. Moreover, the thesis also analyze the optimal retrofit strategy for the buildings in order to find the optimal (lowest) life cycle cost. Furthermore, the current literature has conveyed relatively few studies that combine both LCA and LCC methodology for house types that are common in most towns. The result from the LCA indicated that the house with concrete construction had a little less impact in six of the seven studied environmental impact categories compared to the house made of wood. The result differed slightly when the input data were changed. Regarding the LCCA the house made of wood was roughly 20 % more expensive than its concrete counterpart. Changing the input data revealed no difference in the result. With an interest rate of 7,5 % no retrofits were profitable for either building, however reducing the interest rate to half its original value made it cost optimal to increase the floor insulation for the house made of wood. More studies should be conducted to be able to draw general conclusions regarding which construction material that is the most sustainable. This thesis is based on two specific and real cases. The same result could possibly not be expected from other studies comparing buildings with concrete and wood construction.

The doctoral research revolves around a comparative study of timber modern methods of construction for low-rise, residential buildings in Scotland. The building techniques studied involve both timber-frame panel construction (open-panel and closed-panel systems and structural insulated panels) and massive-timber construction (cross-laminated and nail-laminated timber panels). A non-timber technique is also included in the study: more traditional, load-bearing masonry (blockwork). These different building techniques have been analysed from two complementary aspects: environmental impacts and thermal performance. The environmental study is based on the life-cycle assessment methodology and embraces various aspects: environmental impacts (e.g., climate change, acidification, eutrophication, ozone depletion, etc.), consumption of energy (renewable and non-renewable resources) and production of waste (from non-hazardous to radioactive). The assessment takes a cradle-to-gate approach and, in its structure and method, is informed by the current recommendations of the international standards in the field (i.e., ISO 14040 series). Various environmental trade-offs between construction methods have been identified. In terms of global-warming potential (excluding biogenic carbon sequestration), results suggest that timber-frame buildings show a better performance than masonry buildings; this is particularly true for the open-panel system, which emits about 10% less carbon than the masonry counterpart. Massive-timber buildings tend to cause more carbon emissions than masonry ones. In terms of consumption of non-renewable primary energy, timber buildings do not generally show significant advantages with respect to blockwork-based masonry. In particular, structural-insulated panel systems tend to show very high energy requirements. Timber-based buildings show a tendency to cause increased acidification, eutrophication and creation of low ozone than their masonry counterpart. The level of offsite fabrication that is employed for the erection of the buildings plays an important role in the magnitude of most environmental impacts, which show an average decrease between 5% and 10% when some of the operations are shifted from the construction site to the factory. v The thermal study investigates the performance of the building envelope, and, in particular, of external walls, by means of tests whereby the thermal behaviour of a sample of walls (of full-size section) has been observed and measured over time. On the outside, the walls were exposed to real, natural weather variations throughout the summer. The study especially focuses on the time-dependent response of three different walling systems (which results from their individual cross-sectional arrangements of building components and the associated combination of heat-storage capacity and thermal resistance): a timber-framed wall, a cross-laminated-timber wall and a masonry wall. Thus, the main goal of the study was to characterise the thermal-inertia parameters of these walls. This type of thermal behaviour is related to the repercussions of global climate change at UK level, especially in terms of increase in solar irradiance and temperature, which requires an adaptation of the building-envelope such that it can perform well both during wintertime and summertime, by providing maximum indoor comfort with minimum economic and environmental costs from the construction and operation of buildings. The timber-framed wall possesses the greatest capacity to slow down the propagation of temperature waves from the outer surface to the inner surface (time lag), whereas the masonry wall performs best with respect to reducing the amplitude of temperature oscillation on the inner surface (decrement factor). The cross-laminated-timber wall exhibits intermediate values of both time lag and decrement factor, relative to the other two walls. Both the thermal and life-cycle assessment of the construction alternatives aim at assisting the design and decision-making process in the residential field and at suggesting areas that need to be addressed and improved, towards a coherent evolution of the building techniques included in this study and a step forward in the realisation of sustainable, low-rise dwellings.