Cement bonded wood-wool as external walls have been used around the world since the 1980s. They can have different appearances, wood-wool slabs connected to each other into larger wall elements that are raised between concrete columns and beams. Another type is hollow wood-wool blocks that are stacked on each other and filled with concrete to make an external wall. In 2004 a new building system was launched in Sweden, large prefabricated wall elements of wood-wool. They are connected to each other with concrete columns and beams integrated in the elements to make an external wall. This report is looking into if the concrete beams and columns for the building system are needed. In the report three different tests were made to get the mechanical properties of the prefabricated wood-wool elements. Results showed that there was a large different in the density between the wall elements and it also showed that the modulus of rupture varied between 0.248-0.449 MPa on three identical wall elements. The characteristic modulus of rupture was three times higher than documented in previous reports of a similar wall. The conclusion of this report is that the concrete beams and columns should still be in the wall system.

This report explores the definitions of general- and work lighting in an indoor construction site and how the lighting affects a construction worker. This in order to clarify the controversial topic of: which purpose the ceiling lighting has, thus making the lighting plan optimal. This study was made in cooperation with Skanska Sweden AB. The main ceiling lighting-device in Skanska Sweden is a custom made LED-lamp which is the main tool that this research is based on. The main research methods are project site visits, interviews and surveys in combination with literature studies, and also practical measurements and simulations of the LED-lamps. The results of the interviews and surveys show that comprehension of the functions of the ceiling lighting varies among Skanska Sweden employees. While construction workers generally refer to work lighting when addressing ceiling lighting, the managers tend to refer to general lighting or as a tool to orientate the building. Although, how general lighting is defined, varies among the employees. With that said, the simulations reveal that a reasonable amount of a ceiling lighting will not fulfil the requirements for work lighting for all construction operations. Furthermore, our results from the interviews and surveys confirm those from previous studies; that lighting is essential for the well-being of people. A poorly illuminated workspace dulls one’s work performance and effects one’s health in both the short- and long terms. A well-lit workspace can, on the other hand, reduce the potential health and safety risks on a construction site and also ease multiple work tasks. There are currently no clear assembling routines of ceiling lighting. Therefore, to create consensus on the purpose of lighting and the health and safety prospects that come with it, this report recommends possible solutions and clarifications of the issues and misinterpretations in the matter. / När tidiga byggarbeten utförs inomhus är det vanligt att provisorisk belysning används, dels för att kunna se omgivningen och dels för att kunna arbeta. Skanska Sverige AB uppmanar byggprojekt till att använda taklampor i form av belysningsbojar. Funktionen av den här typen av belysning har på flera projekt varit en kontroversiell fråga där somliga anser att den ska fungera att arbeta i och andra ser det som en orienterande belysning. Det finns inte heller några tydliga riktvärden på vilken ljusstyrka som behövs på en byggarbetsplats.Undersökningen syftar till att dels förtydliga begreppen allmän- och arbetsbelysning inomhus vid byggarbetsplatser och dels utreda belysningens påverkan på yrkesarbetaren. Med hänsyn till detta och lagkrav ska takbelysningens tänkta funktion i byggarbetsplatsens inomhusmiljö utredas. Målsättningen är att skapa en enhetlig syn på belysning inom byggföretaget och underlätta planeringen av den. Utredningen genomförs med en grundläggande litteraturstudie, intervju- och enkätstudier där tjänstemän och yrkesarbetare tillfrågas, platsbesök samt mätningar och simuleringar. Resultaten visar att det finns en varierande uppfattning kring definitionen av allmän- respektive arbetsbelysning. Generellt har yrkesarbetare och tjänstemän olika syn på takbelysningens funktion. Majoriteten av yrkesarbetarna förväntar sig kunna arbeta i takbelysning medan de flesta tjänstemän anser att huvudsyftet är framkomlighet. Vid simuleringar visar sig däremot att den takbelysning som idag används vid Skanskas byggarbetsplatser inte är tillräcklig för att tillgodose kraven på ljusstyrka för alla typer av arbetsmoment som sker på en byggarbetsplats. Resultat från intervjuer och enkäter bekräftar resultat från tidigare utförda studier; att ljusnivån har betydande inverkan på människan både psykiskt och fysiskt. En dåligt belyst arbetsplats påverkar arbetarens förmåga att i stunden utföra arbetsuppgifter men har även långvariga effekter på hälsan. Vidare kan en bra takbelysning kombinerat med riktad arbetsbelysning minska arbetsmiljörisker och underlätta arbetet. Idag finns inga specifika rutiner för planering och utformning av takbelysning även om många tjänstemän utgår från liknande underlag. För att skapa en samsyn kring funktionen och upplysa om arbetsmiljörisker kring belysning ges slutligen rekommendationer som kan tydliggöra funktionen och underlätta utformningen av provisorisk takbelysning.

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The great properties and clear form makes the circular hollow section (CHS) appreciated by architects. When connecting these sections today it is common to use gusset plates. The knifeplate connection where the gusset plate is inserted into a slot made at the end of a circular section, is the most used connection today. This type of connections is not seen as aesthetically pleasingby architects because of its abrupt cut of the CHS. An alternative for the knife-plate connection is the Crocodile nose connection (CN-connection). The benefits of the CN-connection is the absence of the abrupt cut and the protruding gusset plate, which makes it appreciated by architects. In this connection the CHS’s ends are tapered, which creates two semi-elliptical cuts at both sides of the member. On these cuts, appropriate plates arefillet welded. These plates are shaped and bended so that when they are welded in place, the orientation of the extending part is parallel to the member axis. A gap is made between the extending parts so that a gusset plate can be inserted and bolted together with the member. Four different specimens of the CN-connection are tested in order to find the best shape. Two specimens have a stiffener between the plates, at a small distance from the end of the CHS. The difference between the presence of a stiffener and the lack of it, is investigated. The results showed that the specimens with the connecting piece obtained a much higher ultimate load, up to 413 %higher. Two different angles of the CHS’s cut is also investigated in order to see the most appropriate bevelling angle. In this case the results showed that the specimens with the smaller bevelling angle obtained a higher ultimate load, up to 40 % higher. A check of the weld connecting the plates and the CHS is also performed. This check was made with an assumed calculation model. The results showed that the calculation model only was valid for the specimens without the connecting piece. The calculation model must therefore be enhanced, in order to work for all dimensioning cases. / De goda egenskaperna och den ideala formen gör det cirkulära tvärsnittet uppskattat av arkitekter. Vid anslutningar av dessa tvärsnitt är det idag vanligt att använda knutplåtar. Kniv-plåtanslutningar där knutplåten förs in i en öppning i änden av det cirkulära tvärsnittet är det mest använda förbandet idag. På grund av rörets abrupta slut i detta förband är det inte estetiskt tilltalande enligt arkitekter. Ett alternativ för kniv-plåt-förbandet är Crocodile Nose-förbandet (CN-förbandet). Fördelarna med CN-förbandet är frånvaron av det abrupta slutet och den utstickande knutplåten, vilket görden uppskattad av arkitekter. I detta förband är det cirkulära tvärsnittets kanter nerfasade, vilket skapar två semielliptiska skärytor på båda sidor av röret. På dessa skärytor svetsas lämpliga plåtar med kälsvetsar. Plåtarna är formade på ett sådant sätt att när de är svetsas på plats är orienteringen av den utstickande delen parallel med rörets axel. Ett mellanrum mellan de utstickande delarna skapas så att knutplåten kan föras in och bultas fast tillsammans med röret. Fyra olika provkroppar av CN-förbandet testas för att hitta den bästa utformningen. Tvåprovkroppar har en avstyvning mellan plåtarna. Skillnaden mellan närvaron av avstyvningen och frånvaron av den är undersökt. Resultaten visade att provkropparna med avstyvningen fick enmarkant högre brottlast, upp till 413 % högre. För att även hitta den optimala vinkeln på skärytan har två olika vinklar undersökts. I detta fall visade resultaten att provkropparna med den mindrevinkeln gav en högre brottlast, upp till 40 % högre. Även en kontroll på svetsen som binder ihopplåtarna med röret är gjord. Denna kontroll gjordes med hjälp av en antagen beräkningsmodell.Resultatet visade att beräkningsmodellen endast är giltig för provkropparna utan avstyvningen.Beräkningsmodellen måste därför utvecklas, så den kan användas för samtliga dimensioneringsfall.

The position taken in this thesis is that a small and medium sized supplier makes a strategic choice to integrate their supply chain with industrialized house-building companies in order to deliver customer value and sustain competitive advantage. Customer values for industrialized house-building means delivery reliability, product quality, supply chain and market flexibility. Supply chain integration is the means for understanding customer requirements and to use supply chain resources efficiently through collaboration. The purpose of this thesis is to explore a small sawmill transition from single-minded focus on raw material optimization and increased production efficiency towards supply chain integration and customer focus in the industrialized house-building context. The thesis basis is a systematic literature review and five appended papers, based on a longitudinal case study at a small Swedish sawmill. Data has been collected through interviews, participant observations, and archival data during the period of 2010-2012. The theoretical gap is formed by the lack of consensus on supply chain integration. Viewing the criticism it is not clear how the constructs that constitute supply chain integration affect the possibility of succeeding with integration, how the integration should be measured, or how it affects the performance. Hence this thesis makes a holistic approach and collect empirical data trough method development on a strategic (business models, supply chain management), tactical (supply chain planning, sales and operations planning) and operational (value stream mapping, lean value delivery, simulation) supply chain integration process within industrialized house-building context. However, the findings do not conclusively prove or disprove the position. Findings indicate that small sawmills with limited resources and capabilities can employ methods of sales and operations planning, business model decomposition and value stream mapping enhanced decision making. The main contribution is the empirical data on supply chain integration divided and analyzed from strategic, tactical and operational process levels synthesized that with understanding of the importance of integrating these three levels dual perspective. Thus contribute with theoretical enhancement and reduction of the still-identifiable fragmentation of supply chain integration theory. / Godkänd; 2014; 20140423 (jarkko); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Jarkko Erikshammar Ämne: Träbyggnad/Timber Structures Avhandling: Supply Chain Integration for Small Sawmills in Industrialized House-Building Opponent: Professor Christine Pasquire, College of Art & Design and Built Environment, School of Architecture Design and the Built Environment, Nottingham Trent University, Nottingham, England Ordförande: Professor Lars Stehn, Avd för byggkonstruktion och -produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Tisdag den 17 juni 2014, kl 09.30 Plats: F1031, Luleå tekniska universitet / Lean Wood Engineering, TräIN

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Nowadays most people tend to spend a major part of their lives indoors; therefore, the importance of withholding a good internal environment in our buildings is essential. What follows, the thermal indoor climate is strongly influencing the quality and comfort of life in residential areas. This essay will focus on thermal indoor climate situation in a student residence. Based on calculations, measurements and simulations from two different student apartments as well as data collected through a survey, this work will discuss whether the indoor climate complies with the requirements and standards for student housing and what improvement options are available. The survey showed dissatisfaction with the indoor temperature during summer and wintertime. Furthermore, the climate simulation demonstrated the increase in temperature during the summertime, which resulted in a greater dissatisfaction (PPD). Additionally, the calculations made to compare with the climate simulation have also shown that the apartments are getting too hot during summer. IDA ICE logged the relative humidity over a longer period of 1 year, resulting in a range between 5.8% -77.8%. Own measurements such as temperatures, relative humidity, carbon dioxide and exhaust airflows have been set against standards and requirements from authorities and deficiencies of the thermal indoor climate have been mapped. The apartments meet the standard of thermal indoor climate for student housing with one exception -the carbon dioxide content exceeds 1000 ppm in the apartment with the presence of two people. The exhaust airflow in both apartments was lower in our own measurements in comparison to what they were at the OVK protocol from 2014. The exhaust airflow in one apartment had a flow rate of 10 l / s higher than the dimensional flow rate, which indicates imbalance in the system. According to IDA ICE, too high and too low humidity was observed. This may indicate that the apartments do not have a satisfactory sun shading, which plays a significant role in the indoor climate. Using sun shading on all windows could reduce the temperature increase from solar radiation by 50% and the maximum operating temperature could be lowered by 4 degrees in IDA ICE. Using awnings as the sun shading solutions would also lower PPD's high peaks to 10%.

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Buildings subjected to impact and explosion are usually studied using large scale and highly nonlinear finite element model which are time-consuming. The first part of the thesis deals with the development of simple and accurate models for evaluating the nonlinear inelastic behaviour of steel frame structures subjected to impact. The research work in this part has produced four simplified models. The first model concerns with a 4DOF model that reproduces the behaviour of the impacted column. The restraining effect from the rest of the structure is modelled by an elastic spring, a head mass and a static load applied at the top of the column. In the second model, the impacted column is then further simplified using a SDOF model. The behaviour of the SDOF model is governed by an analytical force-displacement expressions of the column loaded by a located force. The maximum displacement of the impacted column can also be determined explicitly by adopting an energy-equivalent approach. Afterwards, in an effort to model the whole structure, two finite element models are developed. For these models, a co-rotational super-element that consists of a beam element and two generalized elasto-plastic hinges is obtained by performing a static condensation. An elastic flexible beam element is used in the first finite element model, whereas a rigid beam element is considered in the second one. In these models, inelasticity is concentrated at generalized elasto-plastic hinges which are modelled by combined axial-rotational springs. The behaviour of the hinges is uncoupled in the elastic range while an axial-bending interaction is considered in the plastic range making it possible to reproduce a wide range of cross-sections and joints. In addition, unilateral contact between rigid point masses is considered and the energy loss during impact is accounted by means of a restitution coefficient following Newton’s impact law. Energy-momentum scheme is used to solve the equations of motion produced by these models. The second part of the thesis concerns with the performance of the connectors in composite steel-concrete slabs under explosion. The purpose is to determine residual capacities of the shear connectors after being damaged by explosion using large-scale pull-out and push-out experimental tests and finite element simulations. / <p>QC 20171106</p>