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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Performance of landfills of hazardous waste with special respect to the function of clay liners

Al-Taie, Laith January 2012 (has links)
This licentiate thesis is based on four papers related to the performance of near-surface low-level (LLW) repositories (landfills) focusing on construction and performance of clay liners in the cappings. The first paper discusses the source of hazardous wastes, their location and their impact on public health. The paper also discusses the scientific basis of the selection of the isolation of such wastes taking in account also cost issues. The paper also shows rules and principles of composing and constructing isolation of such waste according to American and German regulations. The second paper deals with the criteria for locating plants for processing and disposal of hazardous waste in Iraq with special respect to environmental, geological and socio-economic factors. Referring to these criteria a potential disposal site in the Al-Jezira desert is assessed in the paper. The third paper describes the properties of two candidate Iraqi smectitic clays of potential value for isolating hazardous wastes. These clays have been and are still being examined in order to determine their performance and usability for waste isolation. The fourth paper, finally, discusses in detail the hydration-dehydration processes in clay liners in cappings of waste landfills in desertic climates. It also deals with construction issues. / Denna licentiatavhandling är baserad på fyra artiklar med anknytning till utförande av ytnära deponier för lågaktivt avfall (LLW) med fokus på byggande och funktion hos lerlager i topptäckningen. Den första artikeln behandlar ursprunget till farligt avfall, dess förekomst och inverkan på folkhälsan. Artikeln rör också det vetenskapliga underlaget till val av isoleringen av sådant avfall med hänsyn också till kostnadsfrågor. Regler och principer för uppbyggnad av isolering enligt amerikanska och tyska normer redovisas. Den andra artikeln beskriver hur behandling av avfall sker i anläggningar för avfallsdeponering och innehåller förslag till kriterier för placering av sådan verksamhet i Irak med särskild hänsyn till miljömässiga, geologiska och socio-ekonomiska faktorer. Med dessa kriterier som grund visar artikeln att en anläggning i Al-Jeziraöknen kan vara lämplig för behandling och deponering av farligt avfall. Den tredje artikeln beskriver egenskaperna hos två irakiska smektitiska leror som ses som kandidatmaterial för isolering av farligt avfall i Irak. Dessa leror undersöks fortlöpande för att utvärdera deras användbarhet för ändamålet. Den fjärde artikeln, slutligen, behandlar processerna vid bevätning/uttorkning av lerlager i avfallstäckningar i ökenklimat och frågor som gäller byggande av sådana täckningar.
72

Tailings Dam Performance : Modeling and Safety Analysis of a Tailings dam

Knutsson, Roger January 2015 (has links)
Storage and management of mine waste are both needed in the mining industry. After mineral extraction of the ore, there are generally leftovers with insufficient economical value that need to be taken care of. The finest grained fractions are referred to as tailings. Since every mine site and every tailings impoundment is unique, there is unfortunately not an universal answer to proper management that can be applied everywhere. Even though local guidelines and regulations can be considered to give a best practice in terms of design, there is correspondingly a need for dam safety stewardship on an operational level. Without such stewardship, not even the best designed dams or facilities would be fully controlled in terms of safety. Conversely, even badly designed dams can be operated in safe manners with good stewardship and surveillance programs. The coupling between design and stewardship is therefore important in order to reach proper tailingsmanagement.In the design of tailings dams, a certain value of the factor of safety for slopes of the dams is normally striven for to secure stability. The value is generally based on national regulations and/or guidelines. In Sweden the factor of safety should not be lower than 1.5 under normal conditions. In the guidelines, recommendations are often given on dam surveillance and field measurements of e.g. pore water pressure, deformations and seepage. Field measurements are taken, but are generally assessed in terms of trends (change with time) and not by comparison to anticipated performance.In this study, numerical modeling has been used for stability analyses and dam performance, as predictions of deformations and pore water pressure levels. An upstream tailings dam located in northern Sweden has been used as a case. The granular materials being part of the model based were described based upon geotechnical investigations (field and lab). The tailings material was modeled, on a constitutive level, by the Hardening Soil model. Good agreement betweensimulated behavior and laboratory tests was achieved. Other dam materials were simulated by the Mohr-Coulomb model.The model was built as a staged construction model where historical events between 1992 and 2013 were simulated. The historical events included dam raises, increased beach elevations, remedial works etc. The simulations of historical events were used for facilitating comparison with field measurements. By means of inclinometer data, horizontal deformations were measured and evaluated for a period of six years. These deformations were accurately simulated, which was considered to verify the numerical model. By this verification, the model is considered accurate enough to be used for simulating future events. Both stability and corresponding dam performance were computed, by simulating a period of 10 years. The stability analyses were used for the set-up of rockfill support plans, i.e. where and when remedial works are needed in order to maintain a certain safety level. The corresponding values in deformations and pore water pressures were used for the set-up of alert levels for each measuring unit. These alert levels will help the engineer in field with data interpretation, where the simulated values are compared with field measurements taken. The proposed methodology is recommended for tailings dams in general, which reduces the gap between design and stewardship. Hence, one step closer to proper tailings management is taken.
73

Dust from mining area and proposal of dust emission factors

Jia, Qi January 2011 (has links)
Mining generates great deal of particulate matter, especially for surface mining. The principle of dust generation is based on the theory of soil wind erosion. This thesis theoretically and experimentally dealt with mining dust. In chapter 1 the development of study on soil erosion by wind and mining dust were introduced. Chapter 2 elaborated the process of soil wind erosion. Soil motion during wind erosion is classified into three categories which are creeping, saltation and suspension. Threshold wind velocity, which initiates particle motion, depends on particle size, soil moisture, roughness element etc. Roughness element refers to non erodible fraction in a soil. A test on erodible fraction was included in this research.Chapter 3 presented effects and sources of mining dust. Sources include haul road, stockpiles, open surfaces, overburden removal etc. Malmberget mine operated by LKAB is one of the most important iron mines in Sweden. The mining area includes an area with huge open pit and current industrial center area. Both areas are surrounded by residential areas where people are suffering from dust problem. In this research the collected dust from 26 measuring stations during the time period Aug. 2009 to Aug. 2010 were used to calculate the dust fallout and distribution using surfer 9.0 software. It was concluded that two sources for dust generation were spotted. One was located close to the open pit, and the other was located nearby the current mining industrial center. It should be mentioned that the concentration of dust was varying with time. The maximum value happened on May in 2010. The value suddenly became extremely high compared with the other months. This was attributed to a road construction at that time. Analysis results have shown dust production around Malmberget mine was attributed to three reasons: wind erosion of the exposed area closed to the open pit, trucks transportation on haul roads, and wind erosion of stockpiles. Since the mining activities were relatively going at a constant level, the variations of dust level were mostly attributed to the climatic factor. During the research erodible fractions for surface samples from the open surface nearby the open pit were measured. The result showed an erodibility index of 4.69kg/m2 per year. Because the index value indicated relatively low intrinsic soil erodibility, the dust problem might be more contributed by wind erosion of stockpiles and truck travelling on haul roads.Chapter 4 introduced how US EPA developed dust emission factors for various mining activities. Accordingly recommendations and the future plans for the establishment of the dust emission factors for Malmberget mine in Sweden were given and highlighted in chapter 5. Chapter 6 finalizes the thesis with a conclusive paragraph.
74

Rain water harvesting and supplemental irrigation at Sinjar district in northwest Iraq

Zakaria, Saleh January 2012 (has links)
Rainwater harvesting is one of the methods that can ensure availability of water for winter crop in Iraq. Using this technique the excess rainwater (runoff) is stored in reservoirs of dams of different sizes. The water from these reservoirs can be used later when required to satisfy the crops requirements.It is believed that rainwater harvesting will be one of the solutions to overcome water shortages problem in Iraq.This work deals with rainwater harvesting modeling on Sinjar District. The area of study is a plan area located on the northern and southern flank of Sinjar Mountain, within Nineveh province in northwest Iraq. The model was first applied on southern of Sinjar Mountain, where barley crop was chosen as one of the main crops grown in the area. Linear programming technique was adopted to optimize the irrigated area for irrigation scenario of supplemental irrigation (SI) 100% of full irrigation requirements. Two scenarios of operation were considered for each main basin. In the first, each reservoir was operated as a separate unit while in the second all reservoirs in a basin were operated as one system. Both scenarios gave encouraging results. Scenario two however, was relatively better.And then the model was applied again on the northern Sinjar Mountain area. Wheat crop was considered as the main crop grown in the area. A linear programming technique was adopted to optimize the irrigated area for three scenarios of irrigation. They were: 1/supplemental irrigation (SI) 100%, 2/deficit irrigation (DI) 50%, 3/deficit irrigation (DI) 25% of full irrigation requirements. The results of the three scenarios used indicated that, using deficit irrigation (DI) of 50% can be more beneficial than SI of 100% and DI of 25% of full irrigation requirements. These results reflect useful value of RWH and its influence to increase the irrigated area in the studied region.This study had been carried out at Lulea University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Lulea, Sweden.The present work structured in seven chapters, and can be pursued as follows: In chapter 1, Background of the rainwater harvesting, aims of study and research methodology are addressed. In chapter 2, Scope of description of Water Resources in Iraq, Numbers and facts about Iraq, Present water resources conditions in Iraq, Irrigation practices in Iraq, Main Rivers of Iraq, Dams on Tigris and Euphrates Rivers, The impact of Southeastern Anatolia Project (GAP) on water resources in Iraq, Environmental Consequences and Groundwater in Iraq are described.In chapter 3, Information review on rainwater harvesting and supplemental irrigation is presented. In chapter 4, Description of the study area of the Sinjar District, simulation models used in the study and a research methodology are presented.In chapter 5, The results are presented and discussed for southern and northern of Sinjar Mountain. In chapter 6, Summaries for future study: water harvesting and groundwater recharge, water harvesting and its role in increasing crop productivity and the impact of forecasting on water harvesting. In chapter 7, Summaries for the overall conclusions based on the results and then references of the study are listed.Extended of thesis 1-Water harvesting and reservoir optimization of selected areas south Sinjar Mountain, Iraq, Lulea University of Technology, Sweden.Nadhir Al-Ansari, Mohammad Ezz-Aldeen, Sven Knutsson, Saleh Zakaria Submitted to the Journal of Hydrological Engineering. 2- Rainwater harvesting and supplemental irrigation at northern Sinjar Mountain, Iraq, Lulea University of Technology, Sweden.Saleh Zakaria, Nadhir Al-Ansari, Sven Knutsson, Mohammad Ezz-Aldeen Journal of Purity, Utility Reaction and Environment, Vol. 1 No.3,May 2012, 121-141.
75

Foundations of educational buildings in Iraq : past, present and future

Al-Taie, Entidhar January 2013 (has links)
Foundation is considered as one of the main parts of any structure such as buildings, railways, bridges, etc. The type of foundation used is highly dependent on the type and properties of soil. The design of foundations requires many factors that should be defined such as the load that the foundation is going to hold, geological conditions of the soil under the foundation, type of soil and the local building code criteria.There are number of differences in the geological and soil conditions in Iraq. As a consequence, these differences are reflected on the type of foundation to be used. Despite these differences, same materials and style of buildings are used all over Iraq. To have good information about the materials and the required design of the foundation, a comprehensive historical review was executed to highlight the progress of the materials and types of foundation that was used since the dawn of civilization up to the present (ancient, Islamic, Ottoman and British occupation till after independent). Present day situation had been analysed through a case study which illustrated the link between soil and foundation types in three different parts of Iraq (Mosul, Baghdad and Basrah). One building was analysed using STAAD. Pro software in these regions. Furthermore, the same building was analysed using local materials, which were historically used and was compared with present day materials used.It is evident that Iraqi designers and engineers require local code to define all the loads, materials and design of the foundation to be used. The use of local materials might be very effective from both engineering and economic perspectives.
76

Mechanical Properties of Tailings : Basic Description of a Tailings Material from Sweden

Bhanbhro, Riaz January 2014 (has links)
Tailings dams are constructed to store waste material from mining industry and usually these dams are raised with time depending upon production rate. Tailings material is sometimes used in construction of tailings dams. Tailings are artificial material and the behavior of tailings material upon loading is different compared to natural soil materials. The mechanical properties of tailings have influence on the performance of a tailing dam. Since the tailings dams are constructed to withstand for long times, it is essential to understand tailings materials in depth in order to assure safe existence of the dams in short term as well as in long term perspective. This licentiate thesis describes the present work carried out on sulphide rich tailings from one mine in Sweden. The material presented is based upon material from three different papers. The first paper describes the basic characteristics of tailings which includes; specific gravity, phase relationships, particle size, particle shape and direct shear behavior. The second paper discusses direct shear tests carried out on tailings from one Swedish mine. Shear strength parameters are evaluated and results from 27 tests (15 drained and 12 undrained tests) are discussed. This paper also describes the vertical height reductions observed during direct shear tests. The third paper focuses on the laboratory results from triaxial tests conducted on tailings materials. This paper shows the drained behavior of tailings under application of different consolidation pressures.The results from particle analysis showed that smaller particles were very angular and bigger particles were sub angular. The material was classified as silt and silty sand. The average particle density (ρs) is 2.83t/m3. The dry density and void ratios were found to be 1.18–1.65 t/m3 and 0.72–1.41 respectively. During direct shear tests vertical height reductions were observed with slight increment in pore pressures. The strain hardening behavior was observed in both drained and undrained conditions in direct shear tests. The strength parameters determined in triaxial test were higher than of those calculated in direct shear tests. Friction angle ϕ' in triaxial tests were found to be 39 to 41degrees and it did not showed any effect with relation to depth. The cohesion and friction angle in direct shear test at 0.15radian, in drained tests were found as in range of 9.7-33.7kPa and 12.5-18.3 degrees respectively. The same parameters for undrained tests were found as 7.1-16.1 kPa and 16.0-20.4 degrees for cohesion and friction angle respectively.
77

Large-scale testing of granular material

Bergliv, Elin January 2022 (has links)
The main problem to investigate in this study is if larger grained materials, up to 200 mm nominal size, could be used as an embankment material for high-speed railways. High-speed railways have very strict settlement requirements, allowing only very small settlements to ensure safety. To be able to test large grained materials, large devices and unique equipment is needed, something that makes testing and laboratory investigations rarer with increasing grain size. The studies that have been done focus on materials up to about 200 mm nominal size. The literature review finds that there is unclear common conception of how grain size influences the shear strength and deformation properties of a soil material. The most common finding is that increasing grain size results in lower shear strength and increased deformations. Some studies found the opposite and some found no influence of grain size on shear strength. One observation is that the shear strength tends to be unaffected by grain size if the grain strength is equal for all grain sizes. Otherwise the general impression is that larger grains tend to have higher occurrence of fractures and cracks, lowering the grain strength. The study presented herein is performed with a newly developed large-scale simple direct shear device. This device allows testing of grains up to 200 mm grain size. The design includes a free-standing load frame, where the sample is placed in a steel-wire lined rubber membrane on a swing. There are two actuators, one applies vertical force on the sample, while the other applies the shearing motion of the swing. The design is new and allows large forces in both vertical and horizontal direction, without pre-stressing the device. A total of six series are performed on materials with varying grain size, gradation, and grain shape. The findings of the laboratory study includes higher shear strength of well-graded material with larger grains (0-200 mm) compared to a uniformly graded sand with grain size 0-2 mm. The main challenge with the laboratory testing was handling the large amounts of soil material needed for each sample, making it difficult to control the initial void ratio. This is a drawback when analysing the deformation behaviour of the tests. The general behaviour was that the samples underwent initially contraction, which ended with dilatancy and most test reached net increase of volume by the end ofthe shearing.
78

2D Modelling of Geosynthetically Reinforced Piled Embankments : Calibration Methods in PLAXIS 2D & Review of Analytical Guidelines

Sleiman, Maya January 2021 (has links)
This thesis focuses on the 2D modelling of Geosyntheticaly Reinforced Piled Embankments (GRPE) in PLAXIS 2D. In doing so, it explores two main aspects: 1) the calibration of Interface Stiffness Factors (ISFs) governing the soil-pile interaction of Embedded BeamRow (EBR) elements in PLAXIS 2D, and 2) the prospects and limitations of modelling geogrids (GR) in PLAXIS 2D when underlain by EBR elements; although several studies have validates the EBR element in modelling piles, none address the geogrid-EBR interaction and its implications on modelling GRPE systems. The thesis performs the calibration and validation processes using the full-scale GRPE structure ASIRI (Amélioration des Sols parInclusions Rigide) as documented in Briançon and Simon, 2012 and Nunez et al., 2013. Calibration of the EBR’s ISFs is done against 1) load-displacement curve of a test pile, 2)load-displacement of the structure’s monitored piles, and 3) differential soil-pile settlement. Model results for soil settlement, pile settlement, and pile load are then compared to reported values from the ASIRI site. Results show that the natural deviation between the structure and test pile’s load - displacement results in a wide range of possible calibration values for the ISFs, making calibration based on a test pile’s load-displacement curve an unpractical method. Even when such natural deviations were eliminated by calibrating the model against the structure’s reported values for pile load-displacement, model predictions for subsoil displacement were compromised. It is thus advisable to calibrate the EBR element with respect to soil settlement, pile settlement, and pile load rather than solely on a load-displacement curve as to avoid high divergences in soil-pile differential settlement. Modelling geogrids in GRPE systems, PLAXIS 2D underestimates GR strain due to its inability to simulate GR deflection: EBR elements are superimposed on top of a continuous soil mesh, thus allowing the embankment soil to settle through the EBR element. This unrealistically minimizes GR deflection, which underestimates GR strain when modelling GRPEs in PLAXIS 2D. In addition to validating the 2D modelling of GRPE systems, the thesis conducts a comparative literature review of GRPE design guidelines, focusing on the British BS8006 (2010), the German EBGEO (2011), and the Dutch CUR226 (2016). It then applies the latter two to the ASIRI full scale case study and compares results for predicted maximum GR strainand displacement to those from the PLAXIS 2D model and ASIRI measurements. The literature review shows that the geogrid load distribution is highly dependent on the state of subsoil support, where a uniform distribution is more appropriate for high subsoil support, and an inverse-triangular one more appropriate for low subsoil support. However, the analytical analysis of the ASIRI case shows that the triangular distribution, previously dismissed as unrealistic by the literature review, gives satisfactory results due to a combination of soil sliding and high subsoil support at the ASIRI site. / Examensarbetet utvärderar 2D modellering av bankpålning med geosyntetisk armering (Geosyntheticallt Reinforced Piled Embankments – GRPE) i PLAXIS 2D. Examensarbetet utforskar två huvudaspekter: 1) kalibrering av Interface Stiffness Factors (ISFs) som styrjord-påle samspelet av Embedded Beam Row (EBR) element i PLAXIS 2D, och 2) möjligheter och begränsningar vid modellering av geonät i PLAXIS 2D när de ligger över EBR element. Även om flera studier har validerat användningen av EBR element för modelleringenav pålning, har inga behandlat samspelet geonät-EBR samt dess implikationer på modelleringen av GRPE. I arbetet har kalibrerings- och valideringsprocesser genomförts genom att använda den fullskaliga GRPE strukturen ASIRI (Amélioration des Sols par Inclusions Rigide) som dokumenterats i Briançon och Simon(2012) samt Nunez et al. (2013). Kalibrering av EBR ISFshar utförts mot: 1) last/förskjutningssamband av testpålar, 2) last/förskjutningssambad av övervakade pålar i strukturen, och 3) jord-påle differenssättningen. Modellens resultat försättningar i jorden, deformation i pålarna och lasten i pålarna jämförs med mätningar från ASIRI. Resultaten visar att naturliga avvikelser mellan strukturens- och testpålens last/förskjutningssambad resulterar i ett brett spektrum av möjliga kalibreringsvärden för ISFs, som gör kalibrering mot testpålens last/förskjutningssambad opraktisk. Även vid justering för detta genom kalibrering mot strukturpålens last/förskjutningssambad minskade modellens noggrannhet för sättningar i jorden. Det är således lämpligt att kalibrera EBR element motsättningar i jorden, deformation i pålarna och lasten i pålarna i stället för bara last/förskjutningssambaden för att undvika hög divergens i differenssättningen jord-påle. Vid modellering av GRPE-geonät underskattar PLAXIS 2D töjningen i geonäten på grund av sin oförmåga att simulera geonätens utböjning. EBR element ligger över ett kontinuerligt beräkningsnät av jord (soil mesh) som tillåter bankfyllningen att sätta genom EBRelement. Detta förhindrar utböjningen i geonätet som resulterar i en underskattning av töjningen i nätet vid modellering av GRPE i PLAXIS 2D. Förutom validering av 2D modelleringen av GRPE strukturer utför examensarbetet en jämförande literaturstudie av GRPE dimensioneringsriktlinjer med fokus på Brittisk BS8006 (2010), Tysk EBGEO (2011), och Nederländsk CUR226 (2016). De två sista nämnda riktlinjerna tillämpas på ASIRI för att prognosticera maximum geonättöjning och utböjning. Beräkningsresultat jämförs med värden från PLAXIS 2D modellen och mätningar från ASIRI. Litteraturstudien visar att geonätens belastningsfördelning är beroende främst på stödet från den underliggande jorden. Likformig belastningsfördelningen är lämpligare för en hög stödnivå och en invers-triangulär belastningsfördelningen för en låg stödnivå. Dock visar den analytiska analysen av ASIRI strukturen att en triangulär belastningsfördelning, som ansågs vara orealistisk i litteraturstudien, ger tillfredsställande resultat. Det är på grund av kombinationen av ’jordensglidning’ och hög stödnivå från den underliggandejorden i ASIRI:s fall.
79

Grouting Design Considering Different Geological Conditions : Grout evaluation for the extension of the Blue Metro Line

Al Omari, Roaa, Alali, Yasmeen January 2021 (has links)
This thesis forms the basis for a new documented experience of grouting design and work in the extension of the blue metro line in Stockholm. It includes documentation of the grouting design based on theoretical basis, stop criteria and fan geometries for favorable and unfavorable geological conditions. The work is concerned in evaluating the design stop criteria in different geological conditions to assess the efficiency of grouting process, and its compatibility to the maximum permissible leakage according to applications submitted to the land and environmental court in Stockholm. The work was conducted in cooperation with TYPSA AB and SWECO; the joint venture who designed the grouting work. This work was initiated by studying the design documents and reports, requirements, geological and hydrogeological prognosis documents. Six access tunnels were analyzed, with different work percentage based on the actual work achieved at the site at the time of conducting the study. Each access tunnel stretch was determined in terms of geological condition (rock quality), hydrogeological domain, and grouting class (IK1, IK2 or IK3). Evaluations and assessments were done for different aspects including evaluating the grout volume uptake per each grouting class, calculating the percentage of boreholes that stopped by time, volume or zero flow per grouting class, and comparing the measured leakage with prognosed leakage to check the efficiency of the design and implementation phases. RTGC (Real Time Grouting Control) method was also applied on some fans to check its validity in grout optimization, knowing that it is a relatively new method and not yet fully validated. The results showed that geological mappings during the implementation phase were slightly different from the mappings done during the design phase, which is expected due to the high uncertainties in rock mass science. It was also shown that the design stop criteria in this project were promising, through which they have satisfied the requirements according to the application to the land and environmental court. Average grout uptake in typical injection classes were compatible with the results in City Line projects, where the average grout uptake in 2 L/m. However, results also showed that in weakness zones, the average grout uptake was different with high standard deviations. Knowing the fact that unfavorable geological conditions were classified based on different parameters, it is not possible to find one reference value for the grout uptake, but instead results can be used as references in similar geological conditions in main tunnels work and future projects. Some recommendations are made in this thesis on the design stop criteria in weakness zones, surface rock domains, and at fans injected at large water depth. These zones always form the basis for controversial discussions and thus, if documentation of grouting work is carried out and continued in this project, then more knowledge can be gained and transferred to other projects. As part of this thesis, RTGC was applied in favorable conditions where it showed very promising results, the matter that makes it possible to optimize the stop criteria and actual work by conducting trial grouting. However, in unfavorable geological conditions, the RTGC could not be applied because the dimensionality of the flow is 3D, while RTGC was developed for 1D and 1D flow. Therefore, and since it was proven to be as a promising tool, further studies are recommended to develop the method for 3D flow. / Denna avhandling utgör grunden för en ny dokumenterad upplevelse av injekteringsdesign och arbete i förlängningen av den blå tunnelbanelinjen i Stockholm. Den innehåller dokumentation av injekteringsdesignen baserad på teoretisk grund, stoppkriterier och fläktgeometrier för gynnsamma och ogynnsamma geologiska förhållanden. Arbetet handlar om att utvärdera designstoppskriterierna under olika geologiska förhållanden för att bedöma injekteringsprocessens effektivitet och dess kompatibilitet med maximalt tillåtna läckage enligt ansökningar som lämnats in till Mark- och miljödomstolen i Stockholm. Arbetet genomfördes i samarbete med TYPSA AB och SWECO; det gemensamma företaget som designade injekteringsarbetet. Detta arbete inleddes genom att studera designdokument och rapporter, krav, geologiska och hydrogeologiska prognosdokument. Sex arbetstunnlar analyserades, med olika arbetsprocent baserat på det faktiska arbete som uppnåddes på platsen när studien genomfördes. Varje arbetstunnelsträcka bestämdes i termer av geologiskt tillstånd (bergkvalitet), hydrogeologisk domän och injekteringsklass (IK1, IK2 eller IK3). Utvärderingar och bedömningar gjordes för olika aspekter inklusive utvärdering av injektionsmassans upptag per injekteringsklass, beräkning av andelen borrhål som stoppades av tid, volym eller nollflöde per injekteringsklass och jämförelse av det uppmätta läckaget med prognostiserat läckage för att kontrollera effektiviteten av design- och implementeringsfaserna. RTGC-metoden (Real Time Grouting Control) tillämpades också på vissa fans för att kontrollera dess giltighet vid injekteringsoptimering, med vetskap om att det är en relativt ny metod och ännu inte helt validerad. Resultaten visade att geologiska kartläggningar under implementeringsfasen skilde sig något från kartläggningarna som gjordes under designfasen, vilket förväntas på grund av den höga osäkerheten inom bergmassevetenskap. Det visades också att designstoppskriterierna i detta projekt var lovande, genom vilka de har uppfyllt kraven enligt ansökan till mark- och miljödomstolen. Genomsnittligt injektering av injekteringsbruk i typiska injektionsklasser var förenligt med resultaten i City Line-projekt, där det genomsnittliga injekteringen av injekteringsbruk i 2 liter / m. Resultaten visade emellertid också att i svaghetszoner var det genomsnittliga injekteringen av injekteringsbruk annorlunda med höga standardavvikelser. Att veta det faktum att ogynnsamma geologiska förhållanden klassificerades baserat på olika parametrar är det inte möjligt att hitta ett referensvärde för injekteringen av injekteringsbruk, utan resultaten kan användas som referenser i liknande geologiska förhållanden i huvudtunnelarbeten och framtida projekt. Några rekommendationer görs i denna avhandling om designstoppskriterier i svaghetszoner, ytbergsdomäner och vid fläktar injicerade på stort vattendjup. Dessa zoner utgör alltid grunden för kontroversiella diskussioner, och om dokumentation av injekteringsarbete utförs och fortsätter i detta projekt, kan mer kunskap fås och överföras till andra projekt. Som en del av denna avhandling tillämpades RTGC under gynnsamma förhållanden där det visade mycket lovande resultat, det som gör det möjligt att optimera stoppkriterierna och det faktiska arbetet genom att utföra försöksfogning. Men under ogynnsamma geologiska förhållanden kunde RTGC inte tillämpas eftersom flödets dimension är 3D, medan RTGC utvecklades för 1D- och 1D-flöde. Därför, och eftersom det visade sig vara ett lovande verktyg, rekommenderas ytterligare studier för attutveckla metoden för 3D-flöde.
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Soil Nailing: a Monte Carlo Simulation of Soil Parameters

Taule, Christoffer January 2019 (has links)
No description available.

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