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I denna rapport har de två vanligaste tunneldrivningsmetoderna konventionell sprängning och fullortsborrning, TBM undersökts. Konventionell sprängning innebär att små borrhål görs i berget där sprängmedel förs in för att sedan spränga bort materialet. Fullortsborrning innebär å andra sidan att en enda stor borr används vilket gör att tunnelhålet får samma dimension som själva borren. Målen med detta arbete var att ta reda på vilka faktorer som påverkar valet mellan dessa två metoder i Stockholm, att göra en jämförelse mellan metoderna ur ekologisk- och ekonomisk hållbarhetssynpunkt samt att undersöka hur hanteringen och användningen av det uttagna bergmaterialet för respektive metod ser ut. Med hjälp av kvalitativa intervjuer med tio personer inom tunnelbyggnadsbranschen har dessa mål besvarats. De resultat som framkommit visar att det finns ett flertal faktorer som påverkar valet, några mer än andra. De tyngst vägande är de ekonomiska och erfarenhetsmässiga faktorerna som talar till fördel för konventionell sprängning. Fullortsborrning har dock funnits vara den fördelaktiga metoden ur ett hållbarhetsperspektiv, främst eftersom den ger en mindre påverkan på den omgivande miljön. Hanteringen och användningen av det uttagna bergmaterialet har däremot visat att konventionell sprängning kan vara fördelaktigt eftersom det idag finns en etablerad industri kring just sprängt bergmaterial. Fullortsborrat material är idag inte efterfrågat på grund av dess dåliga kvalitet. / In this report, the two most common tunnelling methods are investigated. These are conventional drill and blast and full-face boring, TBM. The drill and blast method is when a small drill is used to make bore holes where the explosives are inserted to blast away the material. Full-face boring is when a single large bore drills a tunnel with the same dimension as the bore head. The objectives of this report were to find out what factors influence the choice between these two methods in Stockholm, to make a comparison between the methods from ecological and economic sustainability point of view and to explore the handling and use of the extracted rock material for each method. By conducting qualitative interviews with ten experts on different aspects of tunnel construction, these objectives have been answered. The results obtained show that there are several factors that influence the choice, some more than others. The predominant aspect is the economic and experiential factors that speak in favour of conventional blasting. Full-face boring, however, has been found to be the advantageous method from an ecological perspective of sustainability, mainly because it has a lower impact on the surrounding environment. Handling and use of the extracted rock material has however proven that conventional drill and blast is the favourable method since there is an established industry around blasted material in Stockholm today. Full-faced drilled material is not in demand today because of its poor quality.

Nowadays, new measurement technologies are being used in underground mining operationsto increase the safety factors and solve several mining challenges to save time and improve theeffectiveness of mining operations. One of the new tools is the uGPS Rapid Mapper, which hasrecently entered the market. LKAB is one of the companies looking to use modern technologyto help solve problems in its Kiirunavaara and Malmberget underground mines. The operatingmechanism of the uGPS Rapid Mapper was studied and some investigations were carried outwith the device.The first part of this thesis studied the repeatability and accuracy of the uGPS Rapid Mapper™System during actual use. A number of tests were completed and data analysis viaCloudCompare software was carried out. The result of these tests showed that the uGPS RapidMapper is an efficient device that can be counted on for future work with higher reliability interms of output results.The second part of this thesis determined the overbreak percentage caused by blasting and otherfactors. The uGPS Rapid Mapper was used to scan different parts of the mine (areas that havebeen developed more than three months ago and newly-developed areas). The percentageoverbreak that occurred in these selected areas in the mine and the cause of the overbreak wereanalysed. The study indicated that the data collected by uGPS and analyzed using theDeswik.CAD (Reconciliation Tool) is a very effective method for calculating the overbreak.Most of the study areas in this study however showed an overbreak percentage of more than16% with a varying form of percentage overbreak. The potential causes of this variation are asa result of geological structures or more pronounced mining activities, or operations such asdrilling and blasting, scaling, charging and explosives parameters. The results also clearlyindicated that underground deformation, rock support installation, especially the application ofshotcrete plays a major role in filling the void after rock falls and reducing geometric crosscutentry size.The final part of the work investigated the deformation that occurred in some parts of the minewhere it is believed to have deformations exceeding 20 cm. These parts of the mine werescanned regularly for four months, and the data were analysed using CloudCompare andDeswik.CAD software. The result of the deformation studies showed that the uGPS RapidiiMapper can effectively recognize the changes underground where the recorded deformationhas exceeded 40 cm.The results confirmed that the uGPS Rapid Mapper can be used to effectively monitorunderground changes in the mine through regular underground scanning and analysis of thescanned data.

Near surface seismic methods have the potential for mapping theoverburden and bedrock in the Nordic environment. They can provideeffective information about shallow glacial deposits and groundwaterresources in Sweden. We analysed seismic data from the Heby andMarsta sites with the aim of improving the imaging resolution andunderstanding the substructures better, developing systematicstrategies to deal with the detection of aquifers and the delineation ofsome significant boundaries. The general scheme for every case studyis composed of processing, inversion and forward modelling.Processing strategies for the Heby and Marsta have different keypoints, because of the different acquisition equipment and systems.The Heby data were acquired by dynamite and collected withconventional geophones, while the Marsta data were acquired by asledge hammer source and a 3C data landstreamer with MEMSsensors. Inversion can be used for enhancing image quality,particularly in velocity model building. Strongly undulatedsubstructures in the Heby profile cause ambiguities and conflictingdips in the stacked section. By employing the tomographic inversionresult as a starting point to implement prestack depth migration(PSDM) the final image shows better continuity at the top of bedrockand shallow layers are resolved clearer. At Marsta, vertical and radialcomponent data were used to obtain PP and PS information,respectively, to delineate the bedrock surface. Common conversionPoint (CCP) binning of the radial component identifies the surface inbetter resolution, even a 2m variation in the depth of the bedrock canbe seen. PSDM radial component data supports and complements theresult from the CCP binning. In both the Heby and Marsta cases,forward modelling was applied for testing processing workflows forthe field data using models that mimick the real substructures.Acoustic modelling was used for understanding the P-wave responsein the Heby single component data, while elastic wave modelling wasperformed to simulate the multicomponent data at Marsta. The resultsdemonstrate that a comprehensive application of seismic methods inthe near surface (shallower than 100m) can provide adequateresolution. Noteworthy is that an accurate velocity estimation plays asignificant role in the whole scheme for seismic imaging. Thestrategies for building the velocity are also meaningful in thisresearch.

The purpose with this study was to investigate the impact of three-dimensional effects in slope stability for three-dimensional excavations and slopes with cohesive soils and compare the results with the method provided by the Swedish commission of slope stability in 1995 regarding three-dimensional effects. Both the factor of safety and the shape of the slip surface was compared between the methods but also the results from their equivalent two-dimensional geometry. The investigation was performed with models created in the finite element software PLAXIS 3D and the limit equilibrium software GeoStudio SLOPE/W. Three-dimensional excavations with varying slope angles, external loads and slope lengths were tested for three different geometry groups in PLAXIS 3D. The equivalent two-dimensional geometries were modeled with SLOPE/W and recalculated with the three-dimensional effect method provided by the Swedish commission of slope stability. The results show that the methods match well for slopes with inclinations 1:2 and 1:1 when an external load is present on the slope edge, and the factor of safety is greater and not close to 1,0. For an excavation with vertical walls or when no external load is present, the methods match poorly. The results also show that for a long and unloaded slope, the factor of safety approaches the value obtained from a simplified two-dimensional analysis. The results imply that the recommendations from the Swedish commission of slope stabilityare reliable for simple calculations of standard cohesive slopes. Keywords: Slope stability; 3D-effects; FEM

In regions of temperate climate the destructive influence of frost action such as frost heave in winter and thaw weakening in spring are the main contributors to severe deterioration of the pavement structure. A number of studies on construction aggregates and field observations of road failures, especially caused by seasonal fluctuations of temperature, have revealed a negative influence of unbound mica-rich rock aggregates on the service life of road construction. The aim of this thesis was to investigate the behaviour of mica-rich aggregates under the temperate climate conditions. The study focuses on measurements of volume change (frost heave), capillarity rise and interaction between water and mica-rich aggregates. The materials studied in this research are commercially available unbound road construction aggregates with varying free mica grains, and originating from different regions of Sweden. The mineral composition of the samples has been determined by polarizing microscopy using a point-count method. In Paper I, the materials were exposed to freeze-thaw cycling in order to register the volume change (in terms of frost heave). The results show that mica-rich base-course aggregates have a large potential to produce frost heave. The results from the test for determining capillary rise (Paper II) indicate a direct correlation between mica content of the aggregates and capillary rise values confirming the capability of mica-rich unbound aggregates to transport and absorb higher amounts of water. The interaction of mica-rich aggregates with water in terms fraction sizes and free mica content was studied in Paper III, measuring water storage capacity and specific water saturation values. The results reveal a strong positive correlation between mica content, grain size, water sorption and water storage capacity of the aggregates. The overall results of this research bring the mineralogy of the fines into focus when evaluating frost susceptibility of unbound aggregates and can be considered when estimating threshold values of free mica grains in crushed road materials. / <p>Godkänd; 2008; 20080611 (ysko)</p>

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Sinkholes are a major geohazard with life-threatening consequences when not properly detected and mitigated. Geologic conditions comprised of soluble bedrock (e.g., limestone or other carbonate-based lithologies) overlain by fine-grained sandy and clayey soils, are known internationally as "karst topography" and is generally characterized by such sinkholes, caves, sinking streams, and highly variable groundwater flow conditions. Karst sinkholes, however, are complex geohazards and are difficult to precisely characterize through geotechnical considerations alone. Deterministic methods (e.g., analytical and numerical solutions) may provide for a more robust analysis of internal soil erosion (known as soil raveling) but have limitations for the practical use by engineers and CPT-operators, and often require additional testing to accurately model the subsurface conditions. Often times when investigating in karst for sinkhole activity, time is a limiting factor and decisions on mitigation efforts or lane closures must be made in a timely manner. Therefore, this study presents a comprehensive investigation into the use of the cone penetration tests (CPT) for the identification and assessment of the internally eroded soils associated with sinkhole formation through field and statistically based solutions. Several CPTs can quickly be performed at any suspected sinkhole site, and results can then be analyzed in real time to aid in decision making. Assessment techniques developed in this study include: 1) CPT-based raveling chart for the identification and evaluation of internally eroded soil in a karst landscape and, 2) a quantifiable vulnerability index, the sinkhole resistance ratio (SRR), used to compare the variation of subsurface conditions within a project site and correlate the potential for future sinkhole collapse. These deliverables were developed through an extensive data collection program of CPTs performed in karst landscapes for sinkhole investigation and repair purposes in central Florida over a 20-year period, and the methodology for the chart and index employed mathematical and statistical methods. The outputs of this research provide engineers with an empirically proven evaluation tool when investigating and designing in a known karst landscape, ultimately enabling a safer and more economical geotechnical design.