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1566 Uppsatser om Dam safety uplift concrete dams buttress dams horizontal joints - Sida 1 av 105
Islastens inverkan på brottsannolikheten för glidning och stjälpning av betongdammar
There are many old dams in Sweden and, since few dams are constructed today, the main task in risk assessment on the existing dams is often to reduce the risk of failure. RIDAS (Swedish Guidelines on Dam Safety) is used when designing new dams and assess the existing ones. The guidelines include stability requirements for different failure modes, e.g. overturning and sliding, which imply that the load effect from e.g. uplift and ice load need to be less than the resisting loads or moments.
Upptryck : En jämförelse mellan RIDAS och internationella riktlinjer
Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).
Dammsäkerhetsutvärdering samt utformning av dammregister och felrapporteringssystem för svenska gruvdammar
A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by tailings dams. The objective of tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition.The objective of this thesis has been to compile information about and evaluate events at Swedish tailings dams and also to develop a collective database for all Swedish mining companies for all tailings dams and all events that occur at tailings dams.Information about 60 events at Swedish tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS.
Säkerhetsklassificering av dammar : En kartläggning av system i Sverige, Norge, Finland, Schweiz, Kanada och USA
In a comparing survey this thesis investigatesclassification systems for dams in Sweden, Norway,Finland, Switzerland, Canada and USA. Theinvestigation is aiming at an understanding of howpotential consequences of a dam failure are takeninto account when classifying dams. Furthermore,the significance of the classification, regarding therequirements on the dam owner and surveillanceauthorities concerning dam safety is considered andreviewed. The thesis is pointing out similarities anddifferences in the line of dam safety.The survey of dam safety is firstly based upon legalrequirements in the different countries andsecondly on guidelines regarding dam safety. Damowners generally are ultimately responsible for thesafety of their dam, and often have their ownroutines regarding how this safety is to be achieved.In this thesis, however, the legal requirements aremainly focused upon.The investigation has resulted in an outlining ofeight areas, where the classification systems in thevarious countries have been compared.
Dammsäkerhetsanalys via stabilitetsberäkningar för Långströmmens kraftverk : En jämförelse mellan olika dimensioneringsmetoder
A detailed dam safety evaluation (in Sweden called FDU) was performed in 2009 by WSP where stability control was performed for Långströmmen power plant with associated spillways. This evaluation concluded that stability could not be ensured, and risk of sliding occurred. The evaluation is based entirely on the recommendations outlined in RIDAS, the power companies guidelines for dam safety, and it is clear that extensive renovations are necessary to stabilize the dam.In this work, the stability will also be checked with guidance through new proposals on guidelines for concrete dams sliding stability, ELFORSK?s report 08:59. This report considered the guidelines in RIDAS as oversimplified, both from an international perspective, but also with regard to the current state of knowledge regarding dam safety.
Inverkan av tvång i gjutfogar och i betongkonstruktioner på
elastiskt underlag: Influence of Restraint in Casting Joints
and in Concrete Structures on Resilient Foundation
In this report, the risk of cracking in joints and/in adjacent concrete is estimated by checking shear forces in joints and the ratio between the actual maximum principal stress ant the actual strength of the concrete. The shear force has been estimated both by simple methods as well as by two-dimensional calculations. The risk of cracking in the concrete and/or in the joints is estimated with the computer program ConStre. The restraint from a resilient foundation or rock on a young concrete construction is estimated by a simple method that is exemplified. It is shown that the restraint can be neglected in some cases.
Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar
This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.
The behaviour of foals before and after weaning in group
Weaning is a standard procedure at most studs, and the methods of weaning varies greatly. The method used at the stud in this particular study is supposed to decrease stress. The purpose of the study was to compare the behaviour of foals in group before and after stepwise removal of their mares.
Standardbred foals with their mothers were kept in three different groups at pasture (12, 11 and 11 foals, respectively, mixed sexes). They had free access to silage and the foals were fed concentrate in a creep-feeding area. By the time the foals were 5 months old, the mares were stepwise removed from the pasture.
Partialkoefficienter för stabilitetsanalys av betongdammar
I Sverige finns det idag ett stort antal dammar och nära hälften av Sveriges elproduktion kommer ifrån vattenkraft. Höga säkerhetskrav ställs på dammarna då konsekvenserna av ett dammbrott kan orsaka stor ekonomisk skada både i form av minskad produktion och som uppbyggnadskostnader. Dammbrott kan även utgöra risk för skador på människor och omkringliggande miljö samt byggnader.Det finns flera dimensioneringsmetoder för att uppfylla gällande säkerhetskrav på konstruktioner. De tillämpningsvägledningar som används vid stabilitetsanalys av betongdammar baseras på gamla deterministiska metoder med säkerhetsfaktorer. Det arbetas med att ta fram nya tillämpningsvägledningar baserat på sannolikhetsbaserade metoder.
Neutral bolagsskatt? : Analys om SOU 2014:40 skapar neutralitet mellan lånat och eget kapital
This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.
ABL:s utvidgade värdeöverföringsregler då ett aktiebolag är komplementär i ett kommanditbolag : Utgångspunkt ur NJA 2014 s. 604
This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.
The laboratory rat : improved welfare for mothers andpups through breeding in an enriched environment?
Maternal behaviour is crucial for the development of the rat pups? behaviour and stressresponses later in life. There are numerous studies evaluating the effects of the dams?behaviours on the pups, but not many addressing what can be made for wellbeing of the ratdams when breeding. Few studies have addressed the question of how the commonly usedrearing environment effects the dams? behaviour and in the long run how it effect the ratsreared to become our research models.
Den urbaniserade Umeälven : Vattenkraftverken som utsträckt urbanisering
This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.
Att påverka en samhällsdebatt : En retorisk studie av organisationen Ruter Dams strategiska kommunikation
Det har aldrig varit så lätt att uttrycka sin åsikt och samtidigt så svårt att faktiskt göra sin röst hörd som det är idag. För att nå ut med sin åsikt måste man uttrycka sig på rätt sätt och i rätt forum. Den här uppsatsen granskar hur man kan påverka en samhällsdebatt genom strategisk kommunikation och uppnå en förändring som kommer från publiken man riktar sig till. Uppsatsen sammanför retorik med strategisk kommunikation och undersöker specifikt hur organisationen Ruter Dam arbetar för att påverka jämställdhet inom svenskt näringsliv. Analysen åskådliggör hur Ruter Dam arbetar mot ett jämställt näringsliv med utgångspunkt i den retoriska situationen, publiker, core message och stakeholders.
Stabilitetsberäkningar och åtgärdsförslag vid islast på Skålandammen
Hydropower is an important source of energy in Sweden and accounts for about 46 % of the total energy production. Sweden has about 1 200 hydropower plants and with the intention of raising the pressure head of the water and to store water, dams are built by the power plants. The storage reservoirs make it possible to adjust the energy production by demand and season. Dams in connection to the reservoirs are subjected to additional loading during periods of high floods or when an icecap in the winter is formed on the reservoirs. In order to maintain the dam safety, the power companies in Sweden are working with guidelines for dam safety from RIDAS.