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Suburban retrofitting : a useful strategy for swedish urban planners? / Suburban retrofitting : en användbar strategi för svenska stadsplanerare?Jusélius, Christoffer January 2013 (has links)
There is an on-going generational shift related to car culture, occurring in the developed world. After decades of increased driving, a decline can now be seen in twenty of the developed countries. Moreover, one out of five regional shopping malls in America is either dead or likely to fail within the next five years. This has given rise to a new urban planning strategy called “suburban retrofitting”. The strategy mainly concerns redevelopment of suburban areas; involving densification of the area’s built environment, a diversification of functions and improved public transportation to the area. The most common mode of public transportation used within suburban retrofitting is light rail. Most suburban retrofitting projects to date have been carried out on sites of dead shopping malls, and the literature focused on suburban retrofitting is, so far, mainly focused on American conditions. Thus the purpose of the thesis is to relate the theories about suburban retrofitting to the Swedish urban planning context, to see if these theories are useful and relevant for Swedish urban planners and policymakers. This question is highly dependent on whether these strategies can be considered to contribute to sustainable development. A case study is carried out about the redevelopment of a commercial area called Kungens Kurva, in Huddinge, south of Stockholm. The area will be denser, take on a city like character and be supplied with public transport. However, some important aspects of this project differ from the theories about suburban retrofitting: no housing is planned, substantial space for parking remains and shopping will still be the dominant activity in the area. The preconditions for suburban retrofitting differs greatly between Sweden and the U.S. Thus, the subjects for suburban retrofitting in Sweden might currently rather be the “million program” suburbs than commercial areas at the urban fringe. One of the reasons for this is that, in Sweden, commercial areas at the urban fringe are often still doing economically well. Which means that the preconditions for fundamentally changing the character of these areas – by introducing housing and diversifying the functions in the area – simply is not good enough. Other factors that make a radical transformation of commercial areas difficult are the strong regulations concerning noise and pollution. It is particularly the regulations concerning housing that make suburban retrofitting projects adjacent to highways problematic in Sweden. As for introducing a light rail system to the area, it is only a rational choice for the Swedish cities that already has such a system. The subway system has proven to be far more effective in diverting car trips to locations at the urban fringe. Therefore it might be a better choice for suburban retrofitting projects in Stockholm. / Det pågår för närvarande ett generationsskifte vad gäller bilkulturen, både i Sverige och i hela den industrialiserade världen. Efter decennier av ökande bilkörning kan man nu se en nedgång i tjugo av de utvecklade länderna. Dessutom har ett av fem externhandelsområden i USA redan lagts ned, eller är sannolikt att bli nedlagt inom de närmaste fem åren. Detta har gett upphov till en ny strategi inom stadsplanering som kallas för ”Suburban retrofitting”, eller ”förtortsomvandling”. Strategin syftar till att omvandla förortsmiljöer och innebär förtätning av den byggda miljön, en diversifiering av områdets funktioner och förbättrad kollektivtrafik till området. I förortsomvandlingsprojekt är den vanligaste typen av kollektivtrafik spårvägssystem. De flesta genomförda förortsomvandlingsprojekt har avsett nedlagda köpcentrum och den litteratur som berör ämnet är i huvudsak fokuserad på Amerikanska förhållanden. Syftet med examensarbetet är att relatera teorier om förortsomvandling till svensk stadsplanering för att se om dessa teorier är användbara och relevanta för svenska stadsplanerare och beslutsfattare. Vilket är en fråga som i sin tur är starkt beroende av huruvida dessa strategier kan anses bidra till en hållbar utveckling. I detta examensarbete genomförs en fallstudie som berör omvandlingen av externhandelsområdet Kungens Kurva, beläget söder om Stockholm. Området planeras att bli tätare, få en kvartersstruktur och förses med kollektivtrafik. Dock skiljer sig projektet från de teorier som finns i litteraturen om förortsomvandling i flera viktiga avseenden. Inga bostäder är planerade, bilen står fortfarande i centrum och shopping kommer fortfarande att vara den dominerande aktiviteten i området. Några av de viktigaste slutsatserna i examensarbetet är att förutsättningarna för förortsomvandling skiljer sig kraftigt mellan Sverige och USA. Framförallt är de ekonomiska förhållandena för externhandelsområden i Sverige fortfarande relativt bra. Dessutom har Sverige starka regleringar vad gäller partikelhalter och buller, vilket kan göra omvandlingsprojekt nära motorvägar svåra att genomföra. Särskilt om de avser bostäder, vilka är en nödvändig del av ett förortsomvandlingsprojekt om det ska anses bidra till en hållbar stadsutveckling. Vad gäller frågan om att införa spårvägsförbindelser till förortsmiljöer under omvandling är detta endast ett rationellt val om man redan har ett spårvägssystem, eller saknar spårbunden kollektivtrafik överhuvudtaget. I det fall man har ett tunnelbanesystem, som i Stockholm, är det sannolikt mer miljömässigt hållbart att utnyttja detta än att bygga spårväg. Det beror på att tunnelbanesystem är betydligt mer konkurrenskraftigt gentemot bilen avseende resor till perifera mål, eftersom tunnelbanetrafiken är separerad från andra trafikslag och därmed får en högre medelhastighet.
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Low-temperature Heating in Existing Swedish Residential Buildings : Toward Sustainable RetrofittingWang, Qian January 2016 (has links)
As an energy-efficient alternative in cold climate countries such as Sweden, low-temperature heating (LTH) technology has shown promising advantages and shortcuts to contribute to the efficiency of heat supply, as well as to the overall sustainability of building performance. The goal of this thesis is to contribute to the development of methodologies and modeling tools to support sustainable retrofitting in the Swedish housing stock. A combination of three integrated modeling techniques was developed. The main focus of this work was implementing LTH in retrofitting practice. The principle of the developed methods can be regarded as a top-down approach, underpinning the general definition of LTH and sustainability criteria. It was found that a preliminary compilation and investigation of the building typology could simplify the retrofitting decision-making. Also, 36–54% of final energy savings could be achieved in studied housing archetypes by effective energy retrofitting. Combining LTH radiators with ventilation heat recovery showed the largest contributions. Below 30 W/m2 (12 W/ m3) heating demand, both radiators (ventilation radiators and baseboard radiator) could work as LTH. These reduced supply temperatures further improved the COP of air-source heat pumps by approximately 12% - 18%. For retrofitting of conventional radiators, there was no concrete evidence to support Type 22 having higher thermal efficiency than Type 21, for the Swedish climate and heating seasons. The achievements and full potential of implementing LTH in retrofitting were found to require not only efficient radiators, but also a well-designed package – insulation, piping, pumping and energy supply system - that suited the current heating demand of the building, given the local climate condition. However, it should also be highlighted that retrofitting incorporating all evaluated measures would not always yield higher long-term economic profits among different archetypes. It is important to find the trade-off between cost-effectiveness and energy savings in similar archetypes - instead of using a “one size fits all” types of solution. For conventional retrofit measures, such as insulations of building envelopes, it was necessary to evaluate the embodied energy during the whole retrofitting process. / Den ökande relativa energianvändningen i bostadsbyggnader i stadsmiljö har lett till högre krav på energieffektivit och hållbar omvandling av redan existerande bostadsbyggnader. En viktig förutsättning för att genomföra en sådan omvandling är att först utveckla metoder för hur effektiva beslut om renovering ska ske, samt att utveckla teknik för hållbar renovering. Lågtemperatursuppvärmning (LTH) har visat sig ha fördelar som ett hållbart och energieffektivt alternativ i länder med kallt klimat som Sverige. Metoden bidra till ökad effektivitet för uppvärmning och minskade energibehov för byggnadskomplexet. Det saknas fortfarande flera steg för hur man ska utforma modelleringsverktyg och utveckla kostnadseffektiva metoder för beslutsfattning och implementering av LTH i redan existerande byggnader. Dessutom försvårar avsaknaden av dessa verktyg och metoder genomförandet av kritiska utvärderingar av renoveringsalternativ utifrån hållbarhets- och effektivitetssynpunkt med huvudfokus på energibesparingspotential, miljöpåverkan och nöjdhet hos de boende. Dessa frågor undersöks i denna avhandling i samband med renovering av existerande bostadsbyggnader i Sverige. Målet är att bidra till utvecklingen av metoder och modelleringsverktyg för hållbar renovering. Under arbetet utvecklades tre modelleringskoncept som integrerats med varandra och som svarar för olika steg i renoveringsmodelleringen. Huvudfokus i arbetet var att göra LTH till en del av vår renoveringspraxis. De renoveringsalternativ som studerats i arbetet inkluderar renovering av klimatskalet för att minska energibehovet samt implementering av LTH-radiatorer och där påvisa deras fördelar för valt primärenergisystem. Analysen omfattar även den sammantagna effekten av och de ömsesidiga beroenden som föreligger mellan olika renoveringsåtgärder. Här utvecklade metoder kan sägas följa en ”uppifrån och ner” strategi och stärker LTH som ett uppvärmningsalternativ som uppfyller hållbarhetskriterier. Avhandlingen visar att effektiv renovering av energisystem kan minska det slutliga energibehovet med 36-54 % i de studerade byggnadstyperna. Kombinationen av LTH-radiatorer med värmeåtervinning från ventilation gav de allra största positiva bidragen. LTH-radiatorerna (ventilationsradiatorer och värmelister) fungerade som lågtemperatursuppvärmning vid uppvärmningsbehov under 30 W/m2 (12 W/ m3) och som ultra-lågtemperaturuppvärmning vid uppvärmningsbehov under 10 W/m2 (4 W/ m3). De låga framledningstemperaturer som leds till LTH-radiatorer bidrar dessutom till att öka COP (värmefaktorn) för luftvärmepumpar med 12 – 18 %, jämfört med traditionella radiatorer med lika stor värmeavgivande area. Något konkret stöd fanns inte för att Typ 22-radiatorer (dubbel konvektionsplåt) skulle ha högre värmeeffektivitet än Typ 21-radiatorer (enkel konvektionsplåt) för svenska klimatetförhållanden. Ökat antal konvektorplåtar visade sig alltså inte nödvändigtvis leda till ökad värmeeffektivitet. Tröskelvärdet för när Typ 11-radiatorer (enkel panel) presterar sämre än den mest effektiva radiatortypen, Typ 21-radiatorer (dubbel panel) som även har bättre exergiprestanda, visade sig vara ett värmebehov av 480 W/rum. För att uppnå full potential för LTH-radiatorer som renoveringsalternativ visade det sig utöver mer effektiva radiatorer även behövas ett välutformat system av rör, pumpar och energitillförsel, anpassade till byggnadens värmebehov före renovering vid rådande klimat. Renovering som inkluderar alla möjliga alternativ leder inte alltid till högre långsiktig ekonomisk avkastning. Det är viktigt att finna en balans mellan kostnadseffektivitet och energibesparing för likande byggnadstyper, i stället för att utveckla en enda lösning som ska passa överallt. För traditionella renoveringsalternativ, så som isolering, var det nödvändigt att utvärdera den inbäddade energin under hela renoveringsprocessen. Stor risk för överskattad hållbarhet föreligger om man inte beaktar detta. / <p>QC 20160929</p> / D6559
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Building integrated technical food systemsJenkins, Andrew January 2018 (has links)
By 2050, it is estimated that food production will need to increase by 70 percent in developed countries and 100 percent in developing countries to meet the demands of future populations. In countries such as the United Kingdom - where the opportunities for increasing food production are limited due to the lack of available land - urban agriculture is seen as a possible solution to meeting increased food demand. However, many cities in the United Kingdom exhibit high building densities and the availability of space at ground level for agricultural activities is in short supply. As a result, the practice of urban agriculture in high-density cities is typically portrayed as a succession of purpose-built edifices that are filled with lettuces or livestock; illustrating a method of food production that is dependent on substantial investment and the demolition of existing buildings to succeed. Within this thesis, these large utopian agricultural skyscrapers are pushed to one side, and existing buildings become the focus of the research; so as to work with cities as they exist today rather than against them. The aim of this thesis is to determine the productivity of building integrated technical food systems and to understand the challenges that face their integration within existing buildings in the future, to calculate the cumulative impact of building integrated technical food systems on UK food security and to understand the potential benefits of building integrated technical food systems such as employment opportunities and the increase in green infrastructure. The delivery of this thesis is not dependent on a pre-existing hypothesis that building integrated technical food systems will drastically improve food security. Instead, this thesis relies on the design of real-world experiments, the development of simulated studies and the construction of logical arguments to quantify and qualify the potential impacts of building integrated technical food systems.
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Multistage Seismic Assessment Methods For Existing Reinforced Concrete Buildings And Their Applicability For Retrofitting Cost EstimationDogan, Onur 01 February 2013 (has links) (PDF)
When the huge building stock in Turkey is considered, it is practically impossible to carry out detailed structural analyses for all of the buildings. In order to cope with the seismic safety evaluation of a large number of existing buildings, it is necessary to use simplified techniques, which can predict the seismic vulnerability of the existing buildings in a relatively short time. The comprehensive structural data compiled for the 48 different reinforced concrete buildings contain full information on their structural characteristics before and after retrofitting and are used in this study.
The first basic goal of the study is to develop a procedure through which the building stock under consideration can be classified as &ldquo / safe&rdquo / or &ldquo / unsafe&rdquo / according to the current Turkish Seismic Code. The classification procedure is based on discriminant analysis. The cross-sectional area of the load-bearing members of a building and its preliminary assessment score are selected as the discriminator variables. The second and ultimate basic goal of the study is to propose a method through which the minimum retrofitting cost for satisfying the provisions of the Turkish Seismic Code can be estimated.
A quick and uncostly assessment of retrofitting cost estimates based on the procedure described in this thesis will provide a useful input for decisions concerning whether a seismically &ldquo / unsafe&rdquo / building should be rebuilt or retrofitted. Such a situation will save time, labor and money, when it is used for the evaluation of building stocks involving large number of buildings and also in urban transformation operations.
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Energy Optimisation of a Building: a Case Study of Ekebyvallen, Uppsala : Profitable investments in a world with rising energy pricesEnarsson, Pär, Hedenmo, Otto, Sillevis Smitt, Dirk-Jan January 2013 (has links)
Energy prices are on the rise, and with it the interest in saving energy. In the housing sector this means that methods for energy optimising buildings, retrofitting, are increasingly important. There are many studies concerning the retrofitting of buildings built before 2000, but less concerning buildings of more recent date. In cooperation with the housing company Uppsalahem, this report explores minor retrofitting solutions for the apartment buildings in Ekebyvallen/Uppsala which were built 2007. The aim was foremost to find solutions for Ekebyvallen but also to assess the possibilities of applying them to a wider range of buildings. A simulation of the energy balance in one of the buildings in Ekebyvallen was performed with the software VIP energy. The simulation together with a field study show weak spots of the energy usage in the buildings and based on these four retrofitting solutions were proposed. The methods; 1) reducing the airflow in the ventilation units, 2) adjusting the heating in common areas, 3) reducing air leakage out of buildings and 4) adjusting the settings of lighting sensors and timers. All are effectively free from investments and also applicable on buildings with similar issues. Thus, these are effective methods of saving energy and consequently, saving money in recently built buildings. The methods are tailored for Ekebyvallen but are with benefit considered for apartment buildings of both recent date and those built before 2000.
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Assessment of critical parameters that affect the seismic performance of bridge steel pedestalsSrivastava, Siddharth 15 May 2009 (has links)
The Georgia Department of Transportation has been installing steel pedestals on bridges, ranging in height up to 33½” (0.85m) to increase the vertical clearance of many multi-span simply-supported and multi-span continuous bridges in Georgia. But there is a concern about the performance of these steel pedestals as they are designed without seismic consideration and may perform poorly compared to high-type steel “rocker” bearings, which were found to be unstable supports in previous earthquakes. This research models a candidate bridge using experimental data that captures the force-displacement hysteretic behavior of the steel pedestals. The results show how these steel pedestals behave when subjected to a range of ground motions. Nonlinear time history analysis is conducted using SAP 2000 software on a three-dimensional model of the candidate bridge. In addition, parametric studies of various critical parameters that can affect the seismic performance of the bridge are investigated, such as 1) varying the mass of the structure, 2) varying the stiffness of the deck joint, 3) varying column heights, and 4) seismic retrofitting using cable restrainers.
The results show that these pedestals should not be used in regions of high seismicity, and in regions of low seismicity, it is likely that they need to be retrofitted. They can, although, be used safely in regions of low seismicity. In addition, it was shown that the mass of a superstructure and height of the columns significantly affect the behavior of these steel pedestals, and should be given a careful consideration before usage. It was also shown that the stiffness of the expansion joints does not significantly affect the displacement of the steel pedestals and the forces transmitted to them. However, if the expansion joints are too stiff compared to the adjacent bridge components, then the forces transferred during pounding of superstructure is increased significantly.
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Strengthening Of Reinforced Concrete Frames By Using Steel BracingsAgar, Mehmet 01 July 2008 (has links) (PDF)
Structures in high seismic risk areas may be susceptible to severe damage in a major earthquake. Structures designed to meet older code requirements may be at even greater risk. When these structures are evaluated with respect to current code criteria, it is observed that they lack of lateral strength and/or ductility. Since safety and economic considerations are major problems, these structures become viable candidates for retrofit and seismic strengthening.
For the variety of structures and possible deficiencies that arise, several retrofitting techniques can be considered. Diagonal bracing system is one of the retrofitting techniques and it provides an excellent approach for strengthening and stiffening existing building for lateral forces. Also, another potential advantage of this system is the comparatively small increase in mass associated with the retrofitting scheme since this is a great problem for several retrofitting techniques.
In this study, the use of steel bracing for the strengthening of low, intermediate, and relatively high rise reinforced concrete frames are investigated analytically. The ultimate lateral load capacities of the strengthened frames are determined by a load controlled push-over analysis. The post-tensioning effect of preloading is also investigated.
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Retrofit of Seismically Deficient RC Columns with Textile- Reinforced Mortar (TRM) JacketsBournas, Dionysios A., Triantafillou, Thanasis C., Papanicolaou, Catherine G. 03 June 2009 (has links) (PDF)
The effectiveness of a new structural material, namely textilereinforced mortar (TRM), was investigated experimentally in this study as a means of confining old-type reinforced concrete columns with limited capacity due to bar buckling or due to bond failure at lap splice regions. Comparisons with equal stiffness and strength fiber-reinforced polymer (FRP) jackets allow for the evaluation of the effectiveness of TRM versus FRP. Tests were carried out on full scale non-seismically detailed RC columns subjected to cyclic uniaxial flexure under constant axial load. Thirteen cantilever-type specimens with either continuous longitudinal reinforcement (smooth or deformed) or lap splicing of longitudinal bars at the floor level were constructed and tested. Experimental results indicated that TRM jacketing is quite effective as a means of increasing the cyclic deformation capacity of old-type RC columns with poor detailing, by delaying bar buckling and by preventing splitting bond failures in columns with lap spliced bars. Compared with their FRP counterparts, TRM jackets used in this study were found to be equally effective in terms of increasing both the strength and deformation capacity of the retrofitted columns. From the response of specimens tested in this study, it can be concluded that TRM jacketing is an extremely promising solution for the confinement of reinforced concrete columns, including poorly detailed ones with or without lap splices in seismic regions.
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Åtgärdsförslag och känslighetsanalys vid energieffektivisering ur ett fuktsäkert perspektiv : En fallstudie på timmerhuset Sofiedals herrgårdOldhammer, Michael, Holmberg, Dan January 2015 (has links)
This thesis investigated the possibilities to resume cultivation of an old manor house built of timber and what this would mean from an energy and moisture perspective. The building in this case study is named Sofiedals mansion and was built in 1858 in Valbo 11 kilometers west of Gävle. The structure of the house was documented and used as a starting-point for carrying out calculations focused on energy and moisture aspects. With the help of a number of computer programs and a conducted air tightness test, the buildings energy consumption were calculated and compared with the current building regulations. In addition, the building was analyzed considering energy retrofitting and what it meant for moisture problems. The energy retrofitting consisted of additional insulation, decreasing the buildings permeability through air sealing; window and door replacements. When a building is equipped with natural ventilation it is difficult to know its precise performance and how an energy retrofitting affects it. Therefore a sensitivity-analysis was performed on four different types of ventilation performance and how they affected the buildings energy as well as its building components moisture performance. The proposed suggestion for an energy retrofitting was made with a potential buyer in mind. Therefore general problems have been documented to demonstrate other measures to be taken into consideration when cultivating the building. The investigation showed that the buildings energy consumption needs to be reduced by approximately 45% to achieve the goal of Swedens current building regulations. Depending on the presumed ventilation performance, the energy consumption and moisture content in the building components varied. The conducted sensitivity analysis showed that a vapour barrier is required to make the building safe from moisture problems. In order to achieve the building regulations energy demands a specific energy consumption of 110kWh/m 2 each year was required. Currently the building does not meet these requirements and needs to undergo an extensive retrofitting. / Detta examensarbete undersökte möjligheterna kring att återuppta brukandet av en äldre herrgårdsbyggnad uppbyggd av timmer och vad detta skulle innebära ur ett energi- samt fuktperspektiv. Byggnaden som undersöktes heter Sofiedals herrgård och är uppförd år 1858 i Valbo 11 kilometer väst om Gävle. Husets uppbyggnad dokumenterades och användes som utgångspunkt för att kunna genomföra beräkningar inriktade på energi och fuktaspekter. Med hjälp av ett antal datorprogram och en tillhörande lufttäthetsprovning kunde husets nuvarande energianvändning beräknas och jämföras med dagens gällande byggregler. Därutöver undersöktes hur byggnaden påverkades ur energi- och fuktsynpunkt genom en energieffektivisering i form av tilläggsisolering, lufttätning, fönster- och dörrbyten. Eftersom det är svårt att kontrollera självdragsventilationens exakta prestanda har en luftflödesanalys gjorts beträffande fyra olika luftomsättningars påverkan av fukt och energiförhållanden för byggnaden. Åtgärdsförslag gällande en energieffektivisering projekterades med en potentiell köpare som bakgrund. Därför har även allmänna problem dokumenterats för att påvisa andra åtgärder som behöver vidtas. Undersökningen visade att byggnadens energianvändning behövde sänkas med ungefär 45 % för att uppnå Boverkets krav. Beroende på vilken ventilationsomsättning som antogs varierade både energianvändningen samt den relativa ånghalten i konstruktionen. En utförd luftflödesanalys visade att vid monterad ångspärr kommer konstruktionen vara fuktsäker. För att uppnå Boverkets energikrav krävs en specifik energianvändning på 110kWh/m 2·år. I dagsläget uppnår byggnaden inte kraven. Eftersom byggnaden beräknades till nästan 200 kWh/ m2∙år måste den genomgå omfattande renoveringsåtgärder.
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The cost-effectiveness of retrofitting sanitary fixtures in restrooms of a university buildingHwang, Byoung Hoon 30 September 2004 (has links)
This study measured the actual water consumption of sanitary fixtures installed in restrooms of a university building while most studies have been based on the manufacturer's reported flow rate. Furthermore, this study analyzed the appropriateness of retrofitting with low-consumption water closets and urinals based on the actual water consumption.
The purpose of this study is to analyze the cost-effectiveness of water savings from retrofitting water closets and urinals in restrooms of the Langford Architecture building A at Texas A&M University. The researcher directly measured the actual water-volume per flush of as-is, tune-up, low-consumption manual, and low-consumption automatic water closets and urinals. The data collected by these observations was analyzed, and the researcher evaluated the water savings of retrofitting water closets and urinals.
Finally, this study provides the actual water-consumption data of sanitary fixtures and proves that retrofitting with low-consumption fixtures can save on water costs. The results will present practical standards to facility managers and other building professionals and will also contribute to determining the feasibility of retrofitting water closets and urinals.
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