The acceptance and the use of cold-formed steel sections has significantly increased in recent years due to advantages such as consistency and accuracy of profile, ease of fabrication, high strength and stiffness to the lightness in the weight. For thin-walled columns, made by folding a plane plate into a section, it is possible that when they are subjected to compression loads they may buckle either locally, if the member is very short, or globally if the member is very long. In addition to local and global buckling, a thin-walled member of an open cross section may also show buckling involving a “distortion” of the cross section. Compared to local and global buckling, distortional buckling is not very familiar and has been discovered only in thin-walled members of open cross sections such as cold-formed steel section columns. The objective of this study is to investigate the behavior of polygonal semi-closed cross-section with pure compression. The study comprise to only elastic buckling and the methodology is consisted by using CUFSM analysis. In order to execute CUFSM of polygonal profiles, the scripts have created which match the Matlab script files (m-files) downloaded from CUFSM 4 open source. The distortional buckling mode is governing as a buckling failure, which occur and dominate in the cases where spring values are 100 kN or higher. However, the contrary result reveals by a decreasing of the spring values. The behavior of the cross-section is dependent on how the interaction of different buckling modes prevails at the corresponding critical half-wavelength. Considering the predomination of distortional buckling mode indicates that the most of polygonal cross-section do not behave as rigid, i.e. as whole cross-section. A reducing of distortional mode and increasing of local mode as well as global mode gives indication that the behavior of the cross-section has changed and turned significantly into more rigid and thus is expected to behave more as whole cross-section.  The more spring values decrease, the higher global mode arises and dominates for the lower slenderness range. The critical half-wavelength for each profile illustrates the needed density between bolts on the longitudinal part of the member. In the interest of eliminating distortional buckling failure, due the fact that distortional buckling is unpredictable, the bolt-density should be lower than the corresponding half-wavelength for the profile where the distortional mode is predominating.

Region Uppsala, who are responsible for the public transport in Uppsala county, are currently building a new city bus depot. Due to capacity shortage in the transmission grid to Uppsala, the operation of the new bus depot must be adapted to a limited power output. In addition to this, the city of Uppsala aims to introduce the first electrical buses by 2021. The purpose of this study was to investigate how electrical buses of different penetration level will affect the power demand at the new city bus depot. The results showed that the current power limitation was already exceeded by 200 kW if 12 electrical buses were to be introduced. Therefore, different technical solutions were evaluated in terms of increasing the penetration level of electrical buses. These solutions were evaluated by a life cycle cost analysis. The cheapest solution was to connect the city bus depot with the regional bus depot. This is possible because the grid connection to the regional bus depot is oversized, compared to its load. However, this solution does not solve the general problem of capacity-shortage in Uppsala and the legality of it must be analyzed further. Two other solutions that were investigated were a local battery storage and a gas engine coupled with a generator at the depot. None of the solutions could solve the power problem at the depot on its own. For a scenario with more than 40 electrical buses, the different technical solutions that were investigated must be combined.

Concrete structures are susceptible to deterioration over time and it is vital to continually assess concrete structures to maintain the structural integrity and prolong the service life. In recent years there has been an increased interest in non-destructive testing of concrete, i.e. assessing the state of the concrete without causing any damage to the structure in the process. There are many different techniques that falls under the term non-destructive testing and one of these that have gained prominence during the last few years is Georadar or ground penetrating radar, often shortened as GPR. GPR is a technique where microwaves are sent into the surface of the concrete by a device, the waves will reflect back to the device when encountering interfaces of areas with different electric properties. The waves are then received by the same device indicating the internal structure of the concrete. This makes the technique an excellent way to find reinforcement bars as the electric properties of concrete and metal strongly differ. In theory though, the technique should also be able to detect other internal differences in concrete, such as voids and corrosion areas but further research is still needed in these areas. This aim of this report is to evaluate ground penetrating radar as a non-destructive technique for assessment of concrete structures. In order to do this different tests has been conducted to evaluate the general performance and usability with a literature review introducing the science behind and what conclusions other researches has reached and using a testing methodology to reach the results. The tests can in a simple way be divided into two parts, first lab tests on a slab in a controlled setting where the internal structure was known, and then two shorter field trips in order to evaluate the performance properly insitu. The results were, to some extent, ambiguous. Although it was found that GPR is an excellent method for finding and locating near-surface reinforcement it was also concluded that the results could vary significantly depending on the location. In one of the field trips the performance of the GPR technique was compared to the performance of traditional cover meter and in this case the portability of the cover meter outperformed the somewhat clunky handling of the GPR. The concrete cover measurement using post-processing of the radar data gave a rough estimate, but once again evaluation still relied on the insitu conditions and the estimate were sometimes questionable. Finding reinforcement below the first layer yielded differing results and it was concluded that further tests were needed to fully evaluate the capabilities of the technique in this regard. The conclusions of the thesis was that although the tests show some potential for the method the results expected from GPR would strongly depend on suitability of the project and experience of the user. One important limiting factor was the availability of devices. For the current project only one specific device was used, it was theorized that another GPR device could get better results depending on the purpose. Furthermore, the lack of experience was also considered to be a limiting factor that might have had an effect on the results. For future research more tests on lower reinforcement and tests on detection of deterioration were suggested. Comparative studies with other similar non-destructive techniques were also considered to be an area of possible interest.

The purpose of this master thesis is to provide suggestions of how composite bridges with I-beams (steel beams and concrete slab connected via shear connectors) can be prepared during the construction phase to withstand a future widening. As a case study the project "Bridge over Kalix river in Kalix" has been used. Tender documents were provided to the stakeholders in September 2018 and the tender answers were at the Swedish Transport Administration (Trafikverket) in mid-January 2019. The construction work is planned for the summer of 2019 and the bridge is planned to be operational by the end of 2020. Widening of bridges is an expensive change of the structure, but is done occasionally. This is mainly due to two factors; higher safety regulations and a higher number on passing vehicles per time unit compared to the 1950 when many of the bridges in Sweden were constructed. Beyond the increased amount of traffic, the vehicle and lorries are heavier nowadays and the expected life time of the bridge construction is longer. The thesis has resulted in three suggestions of widening constructions; one for the case study and two for the general case. The suggestions are based on the change in loads (both shear force and bending moment) caused by dead loads and traffic loads due to the theoretical widening of 2,5 meters. The widened part is constructed to withstand service vehicle (e.g. snow removal vehicle), but the carrying capacity for the rest of the bridge deck is 74-tonnes vehicle. The obtained result shows that both the shear force and the mid-span bending moment increases. The shear force increases in total 45,8 % (dead load 65,8 % and traffic load 7,3 %) and the bending moment 56,7 % (dead load 61,3 % and traffic load 10,0 %). With these value as base the suggested widening construction for the case study is a tilted column with tie beam, both with center distance of six meters. To the general case, two suggestions are provided; The first one with a steel plate placed in the same way as the tilted column, but with a greater load carrying cross section area and thus a greater area to spread the load onto the concrete slab and the web of the beam. The second suggestion is simply an extra I-beam parallel to the existing ones. This is an established method in widenings where the additional load is great, but it is a method highly dependent on the design of the bridge and the surrounding nature. / Syftet med examensarbetet är att ge förslag till hur samverkansbroar med I-balkar kan förberedas vid konstruktion för en eventuell framtida körfältsökning (brobreddning). Som fallstudie har projektet "Bro över Kalix älv i Kalix" använts. Förfrågningsunderlag var intressenter tillhanda under tidig höst 2018 och anbud inkom till Trafikverket i mitten av januari 2019. Byggstart planeras till sommaren 2019 och färdig bro planeras vara i drift till årsskiftet 2020/21. Att bredda broar i efterhand är en kostsamt åtgärd som sker med jämna mellanrum. Detta ingrepp motiveras med att befintliga broar ofta är undermåliga vad gäller säkerhet och framkomlighet, krav på dessa två faktorer har förändrats sedan 50-talet då många av broarna i Sverige byggdes. Utöver ökad trafikmängd har även lasterna ökat (nu till BK4 som innebär 74-tons fordon) och kraven på beständighet av brokonstruktionen, dagens broar ska klara av betydligt högre laster och dessutom dimensioneras för att upprätthålla sin funktion i 120 år. Studien har mynnat ut i tre förslag till breddningkonstruktioner, ett till fallstudien och två till det generella fallet, samverkansbroar med I-balkar. Förslagen grundar sig i beräkning av lastförändring av såväl egentyngder som trafiklaster laster till följd av en teoretisk brobreddning av 2,5 m. Vid konstruktion dimensioneras hela brobanan för BK4 men efter breddning dimensioneras den breddade delen enbart för servicefordon (t.ex. snöröjningsfordon). Erhållet resultat visade att såväl tvärkrafter som böjmoment i fältmitt ökade i den yttre balken i ett mittenstöd (där spannlängden är som störst). Tvärkraftsökningen uppgick till 45,8 % och böjmomentet till 56,7 %. Den föreslagna breddningskonstruktionen till fallstudien var en snedsträva med centrumavstånd om sex meter och med tvärförband mellan I-balkarna på samma S-avstånd som snedsträvorna. Till det allmänna fallet föreslogs en stålplåt, såsom snedsträvan men en utbredd plåt som dels fungerar som livavstyvare till I-balken och dels fördelar lasten på en större yta på såväl betongfarbanans underkant som I-balkens liv. Även ett förslag om att lägga till en extra balk presenterades som förslag då detta är en vedertagen metod då lastökningen är stor och då gestaltningskravet och den omgivande naturen tillåter ett ingrepp och utbyggnad som detta.

The power balance of an electrical power system is crucial to the quality of the delivered electricity as well as the security of supply. In a scenario where Swedish nuclear power plants are being phased out and replaced by renewable energy sources new constraints are added to the power balance equation since the production of many renewable energy sources, such as wind and solar power, are intermittent by nature. This leads to a situation where the currently available regulating power might have difficulties to manage the increasing frequency fluctuations in the power grid. One possible solution to the problem is to build gas turbines for the purpose of peak power generation capacity. An alternative option would be to increase customer flexibility; that is Demand Response. This master thesis investigates how the market for Demand Respond can be designed and which potential Demand Response volumes different policy programs might release. This is done through a mixed approach. Firstly, a scientific review of previously documented Demand Response experiences compares and categorizes different Demand Response programs in a typology based on the parameters cost, volume and feasibility. Subsequently an interview series with different market agents, predominantly through interviews with the Swedish energy intensive industry, identifies the existing Demand Response potential in Sweden and offers the paradigm needed to transfer the results to a future hypothetical situation. The typology of Demand Response programs and estimation of the future industrial Demand Response potential in Sweden are the main new knowledge contributions of this master thesis. The scope however is limited to the Swedish market geographically and focuses on the time horizon 2020-2050. It is also assumed that only existing technologies are likely to be implemented on a large scale over the given time horizon. The results of this master thesis suggest that a Real Time Pricing model would realize the largest potential of Demand Response and to a relatively low cost. This solution however requires actions and further development of both the pricing model and in technology. Firstly, all market agents must have free access to real time price information, something that is lacking today. Secondly, a smart grid with hourly meters is required. If policymakers consider security of supply to be more important than a low system cost, Direct Control or a continuation of the Strategic Reserve is to be preferred according to the conclusions of this report. Previous studies have placed the existing potential for industrial Demand Response in Sweden between 600 and 900 MW. This report suggests that the available volume is in the upper region of the mentioned interval already today and has potential to rise significantly in the future as industries become more aware of the concept and the transmission grid is becoming more flexible. Another driving force for increased Demand Response volumes are the increased price fluctuations which are expected as a consequence of a greater share of renewable energy sources. For the future Demand Response potential, a cost perspective is introduced and a distinction between different response durations is made. More specifically the results indicate that the potential industrial Demand Response volume will be about 1,500 MW in 2030, given a response duration time of 4 h and a spot price on 2,000 SEK/MWh. If 1,500 MW of peak generation capacity could be avoided through active Demand Side Management, it would reduce the system cost with about 350 Million SEK annually. Consequently, there is a business case for Demand Response and the issue is likely to be subject to further investigation and discussion in the future. On the long term however industrial Demand Response must be compared with other flexibility options, e.g. as import/export or energy storages but also residential Demand Response, and is in such case likely to be outcompeted due to its relatively high variable cost of providing capacity.

Syfte: Den svenska byggbranschen tampas med EU:s högsta byggkostnader, låg effektivitet och växande utländsk konkurrens. Anläggningsbranschen är särskilt drabbad. Små- och medelstora företag (SME-företag) har av begränsade möjligheter att implementera metoder för att effektivisera produktionen och kan därför behöva stöd med detta. 5S är en metod för att organisera en arbetsplats eller en produktionslinje. Syftet med 5S är att med små medel minimera icke värdeskapande aktiviteter. Med en välorganiserad och funktionell arbetsplats ges stora möjligheter till ökad produktivitet. Rapportens mål har varit att undersöka hur ett traditionellt styrt byggprojekt förändras då 5S implementeras i produktionen. Metod: För att uppfylla målet har 5S implementerats i ett anläggningsprojekt. För att kartlägga resultaten och samla in empiri har en strukturerad utfrågning och flera intervjuer genomförts med den berörda personalen och fältobservationer har genomförts. Dessutom har en litteraturstudie genomförts för att kartlägga forskningsfronten och vilka problem som eventuellt kan uppstå. Resultat: Resultatet visade att 5S är en enkel och kraftfull metod för att åstadkomma ökad effektivitet och ordning på en byggarbetsplats. Genom att anpassa 5S efter anläggningsbranschens förutsättningar och genom att motivera personalen bidrog 5S till att arbetsplatsens produktivitet och arbetsmiljö förbättrades. Konsekvenser: Konsekvenserna av rapporten är att entreprenadföretaget kommer att tillämpa 5S i sin produktion. Rekommendationerna är att företaget bör utse en 5S-ansvarig i varje arbetslag, kontinuerligt hålla 5S-möten i produktionen samt implementera 5S i ett projekt åt gången då alla anläggningsprojekt har mer eller mindre unika förutsättningar. Begränsningar: Arbetet avgränsades till att behandla 5S i ett relativt småskaligt projekt i ett SME-företag verksamt inom anläggningsbranschen. Resultatet är troligtvis unikt för den typ av byggprojekt som behandlats då arbetet varit beroende av ett antal individers engagemang och förståelse. Nyckelord: 5S, Lean, SME-företag, implementeringsproblematik, anläggningsbranschen. / Purpose: The Swedish construction industry faces issues such as having the highest construction costs in the EU, experiencing low efficiency and facing growing foreign competition. The civil engineering industry is particularly affected. Small and medium sized enterprises (SMEs) have limited possibilities to implement methods to improve efficiency and may therefore need support. 5S is a method of organizing a workplace or a production line. The purpose of 5S is to minimise non value creating activities by using small means of resources. With a well organised and functional workplace, possibilities are provided for increased productivity. The objective of the thesis has been to analyse how a traditionally managed civil engineering project alters when 5S is implemented in the production. Method: To fulfil the objective of the thesis, 5S has been implemented in a civil engineering project. To survey the results, a questionnaire and several interviews have been conducted with the project staff involved and field observations have been made to collect empirical data. In addition, a literature study has been conducted to map the existing research on the subject and to find which problems may arise during implementation. Findings: The result showed that 5S is a simple and powerful method for achieving increased efficiency and order at a construction site. By adapting 5S to the conditions of the civil engineering industry and by motivating staff, 5S contributed to improving the workplace's productivity and working environment. Implications: The implications of the thesis is that the civil engineering company will practice 5S in its production. The recommendations are that the company should appoint a 5S manager in each work team, continuously hold 5S meetings in production and implement 5S in one project at a time as all civil engineering projects have more or less unique conditions. Limitations: The thesis was delimited to treating 5S in a relatively small-scale project in a SME company within in the civil engineering industry. The result is probably unique to the type of construction projects that was analysed as it was dependent on the involvement and understanding of certain individuals. Keywords: 5S, Lean, SME-companies, implementation issues, civil engineering industry.

The goal of this master thesis is to study the challenges the contractors are experiencing when building in the project E4 The Stockholm Bypass (E4 Förbifart Stockholm) by using digital models. This is the first step for The Swedish Transport Administration towards the process of implementing BIM in the construction industry, which has led to several challenges and therefore is important to evaluate. The work of building E4 The Stockholm bypass can be seen with a sociotechnical perspective, since both humans and complex technology systems are involved in the project. The study used a qualitative method by interviewing the contractors, the promoters of the model and The Swedish Transport Administration. Furthermore, workshops were held with construction managers, BIM- specialists and the contractors’ measurement surveyors. The results were analysed by the theories regarding Human-Technology-Organisation (HTO), Human-Technology Interaction (HCI) with focus on usability and information management. The study resulted in a couple of recommendation to The Swedish Transport Administration. The main aspects were to involve the contractors earlier in the development of the models; have easily available information in the models necessary for production; change the contractors sceptical attitude towards BIM by listening to their issues; have a clear communication through the existing informations paths and create a common standard of format regarding exchange of information. By following the recommendations, the challenges regarding the work of the contractor will decrease and the implementation of models and BIM could proceed more efficiently.

Företagen LKAB och SJ är statligt ägda aktiebolag som har målsättningen att bedriva en säker och lönsam verksamhet. Båda företagens verksamheter är starkt förknippade med tågtransporter av olika slag, där LKAB transporterar malm mellan gruvorna i malmfälten och deras malmhamnar på kusten, och SJ som bedriver persontrafik med cirka 1200 dagliga avgångar från deras 284 olika stationer. En av de viktigaste förutsättningarna för bolagens existens är förmågan att utöva järnvägstransporter med rälsgående fordon på ett lönsamt och effektivt sätt. För att uppnå detta krävs ett driftsäkert och tillförlitligt järnvägssystem, vilket är starkt förknippat med förmågan att underhålla rullande material. Syftet med studien var att undersöka möjligheterna att förbättra det förebyggande underhållet av rälsgående fordon och på så sätt bidra till minskade underhållskostnader och ökad livslängd på hjul, axlar och räls. Målet var att undersöka ifall mätning av laterala och vertikala krafter kunde användas för att identifiera skador och slitage hos hjul i ett tidigt skede, på så vis ges möjlighet att övergå till att optimera det tillståndsbaserat underhåll.   Metoden för arbetet gick ut på att identifiera individer i form av vagnar eller lok från de båda aktörerna som visade avvikande mätvärden vid passage genom mätsystemet StratoForce i Sävast. Uppmätta krafter från aktuella passager analyserades grafiskt för att ge en överskådlig bild av fordonens försämring över tid. Beroende på vilka krafter som var avvikande kunde ett antagande om hjulens slitage eller eventuell skadetyp göras. Det fortsatta arbetet gick ut på att göra en okulär avsyning av individen för att om möjligt hitta korrelationer mellan uppmätta krafter och fysiska skador eller slitage på hjulen. Vid enstaka tillfällen användes även optiska och mekaniska mätverktyg vid avsyning.   Behovet av mätsystem för tillståndsövervakning är stort, detta är något samtliga parter är överens om. Resultatet av utvärderingen visar att det finns korrelationer mellan analyserade krafter och skicket på avsynade hjul, exempelvis hade höga vertikala vibrationer en tydlig koppling till ytskador. Vår bedömning är att mätsystemet i kombination med kvalitativ analys redan i dag kan användas för tillståndsövervakning av rullande material på järnvägen. Begränsningarna ligger i att knyta krafternas storlek till skadornas omfattning, något som till största delen beror på brister i mätutrustningens placering.

Common practice in acoustic design does not consider air gaps. Thereare different opinions about air gaps and their affect on noise reduction.The report analyzes the credibility of the requirements used in a theoretical calculation model that addresses noise reduction in acoustic screens. Several measurement results from empirical attempts in a realistic environment for different screen models are compared.The result shows that a horizontal 50-millimeter gap has no noticeable impact on noise reduction. The result for horizontal air gaps against ground is of particular interest as it allows a simplified foundation to be used.Vertical air gaps have a greater negative influence on noise reduction but the results presented in the report can be used when lower demands are set on screens.An economic analysis shows that the result from the experiment when using a simplified foundation results in a cost reduction ofapproximately 300 SEK per meter acoustic screen.

Due to the environmental issues, the amount of installed solar power increases. In the same time, the electric vehicle fleet is expanding rapidly. Those two growing technologies, if not controlled, can cause various unwanted effects for the electricity grid. In order to decrease their negative effects on the grid and benefit from it at the same time, these technologies have to work in synergy with each other. This synergy can be enabled through smart charging of electric vehicles. Therefore, the aim of this study is to develop a smart charging algorithm which uses solar production forecasts to charge the vehicles at a workplace. Furthermore, the goal is to examine how such control of the charging affects the self-consumption of solar power, self-sufficiency and the amount of energy imported from the grid as opposed to uncontrolled charging. To fulfill the goal, the algorithm was developed based on solar production forecasts. The forecasts were created through autoregressive models, AR and ARMA which were estimated using the actual solar production data collected at one of Uppsala regions solar production plants. Also, a case where ideal forecasts were used was applied. Furthermore, the charging need for various number of cars was simulated for every working day throughout an entire year in order to simulate the application of the algorithm and examine its performance but also to simulate the uncontrolled charging. The results, compared to the uncontrolled charging, show that the algorithm is able to increase the self-consumption of solar power by an average of 9,33 – 25,30 percentage points for 10 – 50 charging cars. It is also able to increase the selfsufficiency by an average of 42,65 – 31,28 percentage points for 10-50 cars respectively thus reducing the need of electricity imports from the grid. Furthermore, it was discovered that the results, the self-consumption and selfsufficiency, from the simulations with ideal forecasts differed only by up to 2 percentage points from the simulations where the forecasts were created through an AR(9) model (AR model of order 9). This allows a conclusion that a simple AR(9) model is completely sufficient to create forecasts that are good enough to produce satisfactory results. In general, it is concluded that the algorithm developed in this study is successful when it comes to increasing the self-consumption of the solar power, the selfsufficiency and decreasing the amount of energy needed from the electricity grid. This limits the negative impacts that the increasing solar power production and the growing electric vehicle fleet have on the electricity grid.