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  • 1351.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Eigenbrod, Dieter
    Lakehead University, Thunder Bay, Ontario.
    Stone movements and permeability changes in till caused by freezing and thawing2000Inngår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 31, nr 2, s. 151-162Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Vertical uplifting of boulders and stones is well known to take place in cold regions. Movements of stones in roads might lead to traffic danger, vehicle failures, and cause breakdown of the road surface with the need of expensive repair as a consequence. In addition, freeze/thaw and associated stone movements may cause an increase in permeability, which can lead to contamination of soils and ground water if used as soil liners in landfill areas or even dam failures if used as hydraulic barriers in earth dams. Freeze/thaw tests were carried out in the laboratory on a silty sandy soil in order to study movements of embedded stones and to measure how the overall permeability was influenced by freeze/thaw cycles. The soil samples were compacted at three different water contents, i.e. 11.5% (optimum), 14.5%, and 17.5%. Each sample contained one stone, placed at a predetermined depth. The soil samples were subjected to one-dimensional open system freeze/thaw. Soil temperatures, volume changes, and stone movements were measured. The results showed that upward stone movements took place due to freeze/thaw in the frost susceptible soil compacted at and 3% above the optimum water content. In addition, the permeability increased in samples with initial water contents of 11.5% and 14.5%. This permeability increase was as much as 81 times after six freeze/thaw cycles. For the samples with initial water contents of 17.5%, very small changes in permeability were measured. Vertical uplifting of boulders and stones is well known to take place in cold regions. Movements of stones in roads might lead to traffic danger, vehicle failures, and cause breakdown of the road surface with the need of expensive repair as a consequence. In addition, freeze/thaw and associated stone movements may cause an increase in permeability, which can lead to contamination of soils and ground water if used as soil liners in landfill areas or even dam failures if used as hydraulic barriers in earth dams. Freeze/thaw tests were carried out in the laboratory on a silty sandy soil in order to study movements of embedded stones and to measure how the overall permeability was influenced by freeze/thaw cycles. The soil samples were compacted at three different water contents, i.e. 11.5% (optimum), 14.5%, and 17.5%. Each sample contained one stone, placed at a predetermined depth. The soil samples were subjected to one-dimensional open system freeze/thaw. Soil temperatures, volume changes, and stone movements were measured. The results showed that upward stone movements took place due to freeze/thaw in the frost susceptible soil compacted at and 3% above the optimum water content. In addition, the permeability increased in samples with initial water contents of 11.5% and 14.5%. This permeability increase was as much as 81 times after six freeze/thaw cycles. For the samples with initial water contents of 17.5%, very small changes in permeability were measured. Vertical uplifting of boulders and stones is well known to take place in cold regions. Movements of stones in roads might lead to traffic danger, vehicle failures, and cause breakdown of the road surface with the need of expensive repair as a consequence. In addition, freeze/thaw and associated stone movements may cause an increase in permeability, which can lead to contamination of soils and ground water if used as soil liners in landfill areas or even dam failures if used as hydraulic barriers in earth dams. Freeze/thaw tests were carried out in the laboratory on a silty sandy soil in order to study movements of embedded stones and to measure how the overall permeability was influenced by freeze/thaw cycles. The soil samples were compacted at three different water contents, i.e. 11.5% (optimum), 14.5%, and 17.5%. Each sample contained one stone, placed at a predetermined depth. The soil samples were subjected to one-dimensional open system freeze/thaw. Soil temperatures, volume changes, and stone movements were measured. The results showed that upward stone movements took place due to freeze/thaw in the frost susceptible soil compacted at and 3% above the optimum water content. In addition, the permeability increased in samples with initial water contents of 11.5% and 14.5%. This permeability increase was as much as 81 times after six freeze/thaw cycles. For the samples with initial water contents of 17.5%, very small changes in permeability were measured.

  • 1352.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Deformation and compaction of frozen soils1994Inngår i: Ground freezing 94: proceedings of the seventh International Symposium on Ground Freezing, Nancy, France, 24-28 October 1994 / [ed] Michel Fremond, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1994, s. 109-116Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Frozen soils compaction are understood to give fills with low densities. Thus, relatively large deformations often occur when such fills melts. The most important factors influencing the obtained dry density, and consequently the thaw deformations, are compaction effort, temperature, water/ice content and soil type. A laboratory investigation was conducted in order to quantify the different factors influencing the obtained degree of compaction, as well as related thaw deformation. The results indicated that the water content of the soil is the most important factor for the obtained dry densities and for the thaw compressions

  • 1353.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hur påverkas jord av frysning och tining2000Inngår i: Bygg & Teknik, ISSN 0281-658X, Vol. 92, nr 1, s. 59-61Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 1354.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laboratoriepackning av frusen jord1995Inngår i: 12th Nordiska Geoteknikermötet, June 26-28, 1996, Reykjavik, Iceland, 1995, s. 159-168Konferansepaper (Annet vitenskapelig)
  • 1355.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laboratory study of the compaction properties of frozen soils1993Inngår i: Frost in geotechnical engineering: proceedings of the 2nd international symposium on Frost geotechnical engineering, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1993, s. 69-77Konferansepaper (Fagfellevurdert)
  • 1356.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Permeability changes in a fine-grained till du to cycles of freezing and thawing1997Inngår i: Ground Freezing 97: frost action in soils : proceedings of the International Symposium on Ground Freezing and Frost Action in Soils / Luleå / Sweden / 15-17 April 1997 / [ed] Sven Knutsson, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1997, s. 193-202Konferansepaper (Fagfellevurdert)
  • 1357.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Uppfrysning av block och stenar i vägar1999Inngår i: Bygg & Teknik, ISSN 0281-658X, Vol. 92, nr 1, s. 39-41Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 1358.
    Viklander, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Magnusson, O.
    Luleå tekniska universitet.
    Laboratory compaction using an enlarged fall-weight apparatus1994Inngår i: Proceedings: Thirteenth International Conference on Soil Mechanics and Foundation Engineering, New Delhi/5-10 January, 1994 = Comptes rendus / Treizième Congrès international de mécanique des sols et des travaux de fondations, New Delhi/5-10 janvier, 1994, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1994, Vol. 1, s. 425-428Konferansepaper (Fagfellevurdert)
  • 1359.
    Vikström, Lars
    Luleå tekniska universitet.
    Uppmätta och beräknade tjällyftningar och tjäldjup i jord: en analys av ingångsparametrarnas betydelse för beräkningsresultatet1999Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [sv]

    Målet med arbetet som ligger till grund för licentiatuppsatsen har varit att bestämma behovet av och omfattningen på fält- och laboratorieundersökningar för att erhålla tillförlitliga resultat från beräkningar med programmet Pc-heave. Utgångspunkten har varit att studera om man enbart med en enklare fält- och laboratorieundersökningar kan erhålla ingångsparametrar som ger tillräcklig noggrannhet vid predikteringen av tjällyftning och tjälnedträngning i en jord med hjälp av programmet Pc-heave. Syftet har varit att beräkningen skall vara en prognos och utföras utan att i efterhand behöva anpassa parametrarna för att uppnå överensstämmelse mellan beräknade och uppmätta värden på tjälnedträngning och tjällyftning. Med anpassning av sådana parametrar som, mängd ofruset vatten och permeabilitet, utifrån en kortare tids, en månads, observationer i inledningen av tjälningsperioden erhåller man god överensstämmelse mellan beräknade och uppmätta värden på tjällyftning, islinsernas läge och mäktighet och tjälnedträngningen. Islinsernas läge och mäktighet i den frusna jorden har detekterats med hjälp av röntgenfotografering av upptagna borrkärnor. Ingångsparametrar valda utifrån enklare undersökningar av typen kornfördelning, densitet, vattenkvot eller ytterligare parametrar bland annat ofrusetvatteninnehåll och permeabilitet bestämda i laboratorium ger däremot sämre resultat.

  • 1360.
    Vikström, Lars
    et al.
    Luleå University of Technology.
    Bernspång, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Strength and deformation behaviour of snow and snow structures: field and laboratory measurements at Icehotel Jukkasjärvi, Winter 2000 - 20012002Rapport (Annet vitenskapelig)
    Abstract [en]

    Density measurements, unconfined compression tests, creep tests, beam tests, and measurements of deformations were performed on snow and snow structures that formed the Icehotel during the winter 2000/2001. Results from the unconfined compression tests and creep tests showed that: At -5ºC unconfined compression strength was 0,598 MPa with a snow density of 532 kg/m3. Axial viscosity was 3,23·106 MPa-s and compactive viscosity was 5,24·106 MPa-s with a snow density of 524 kg/m3. At -10ºC unconfined compression strength was 0,681 MPa with a snow density of 558 kg/m3. Axial viscosity was 1,92·106 MPa-s and compactive viscosity was 1,38·106 MPa-s with a snow density of 518 kg/m3. At -11ºC unconfined compression strength was 0,879 MPa with a snow density of 550 kg/m3. Axial viscosity was 2,16·106 MPa-s and compactive viscosity was 2,79·106 MPa-s with a snow density of 470 kg/m3. Beam tests were performed on snow from a pile of artificially made snow. This type of snow was used to construct the arcs of the Icehotel. Results from the beam tests showed that the snow had a mean density of 510 kg/m3 and that Young's modulus E had a mean value of 335 MPa. At failure mean value of maximum tensile- and compression stress was 0,375 MPa and mean value of maximum shear stress was 0,039 MPa. During the winter 2000/2001 deformations of the church building were measured. Results show that the apex of the arcs actually rose 4 to 8 cm, though the shape of the arcs changed very little. Comparing results from this investigation with results from earlier investigations made on snow with similar densities showed that: Unconfined compression strength was 20 to 40 percent lower. Axial viscosity was similar in all but one test at -10/-11 ºC. Axial viscosity was in all tests higher at -5 ºC. Compactive viscosity was higher in all tests. Results from the beam tests regarding Young's modulus values and tensile strength showed similar results.

  • 1361.
    Vikström, Lars
    et al.
    Luleå tekniska universitet.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    A comparison between measured and calculated frost heave, frost penetration and formation of ice lenses1997Inngår i: Ground Freezing 97: frost action in soils : proceedings of the International Symposium on Ground Freezing and Frost Action in Soils, Luleå, Sweden, 15-17 April 1997 / [ed] Sven Knutsson, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1997, s. 297-305Konferansepaper (Fagfellevurdert)
  • 1362.
    Vranckx, Alexander
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Effect of heterogeneous densification due to vibroflotation on liquefaction resistance2017Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
  • 1363.
    Weber, Toni M.
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Centrifuge modelling of sand compaction piles in soft clay under embankment load2006Inngår i: Physical Modelling in Geotechnics, 6th ICPMG'06: Proceedings of the 6th International Conference on Physical Modelling in Geotechnics, 2006, Vol. 1-2, s. 603-608Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Sand compaction piles are used in practice for ground improvement of soft subsoil in order to accelerate consolidation, reduce compressibility, and increase strength. The current design procedure of sand compaction piles is based on simple empirical calculations, which does not take full account of the sand pile behaviour. This research project investigates the behaviour of a base reinforced embankment constructed on a soft clay layer, which is improved with sand compaction piles. In order to gain a better understanding of interactions within the structure, physical investigations are being conducted by means of centrifuge modelling. Tests were performed under plane strain conditions in a strong box, using a newly developed sand compaction pile installation tool for in-flight pile construction. Initial analysis of test data shows the change in stress state due to sand compaction pile installation and the influence on clay behaviour. © 2006 Taylor & Francis Group, London.

  • 1364.
    Weber, Toni M.
    et al.
    Institute for Geotechnical Engineering, Swiss Federal Institute of Technology.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Swiss Federal Institute of Technology.
    Springman, Sarah M.
    IInstitute for Geotechnical Engineering, Swiss Federal Institute of Technology.
    Modelling the inflight construction of sand compaction piles in the centrifuge2005Inngår i: Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering: Geotechnology in Harmony with the Global Environment, 2005, Vol. 3, s. 1291-1294Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Sand compaction piles are used in practice for ground improvement of weak subsoil. These columnar inclusions improve the consolidation behaviour as well as reduce the compressibility of the soft ground. The current design procedure of these sand piles is based on simple empirical calculations, which does not fully take account of the sand pile behaviour. In order to gain a deeper understanding of the behaviour of sand compaction piles, physical and numerical investigations are being conducted. The basic system behaviour of soft soil and column is simulated physically by centrifuge modelling. Because the stress situation in the soil changes significantly due to installation, a sand compaction pile installation tool was developed and applied successfully in the first tests. This allowed the stress paths encountered by the soil during the construction process of a displacement sand pile to be modelled realistically. The results will be compared to real geometries and the behaviour is also studied numerically by means of finite element modelling. These findings provide the basis for further analysis of this geotechnical interaction problem extending the model by including geotextiles below embankments to be able to formulate some recommendations for the design procedure of sand compaction piles under embankments.

  • 1365.
    Weber, Toni M.
    et al.
    ETH Zurich, Institute for Geotechnical Engineeering, Studer Engineering, Institute for Geotechnical Engineering, Zurich.
    Plötze, Michael L.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Peschke, Gerd
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich, Institute for Geotechnical Engineering, ETH Zurich.
    Smear zone identification and soil properties around stone columns constructed in-flight in centrifuge model tests2010Inngår i: Geotechnique, ISSN 0016-8505, E-ISSN 1751-7656, Vol. 60, nr 3, s. 197-206Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stone columns are primarily used for the purpose of ground improvement in fine grained soils in order to reduce settlements and the risk of bearing failure. They are also designed to improve the drainage conditions in the ground and to accelerate the consolidation processes within the clay. However, smear and disturbing effects caused during the construction of stone columns result in degradation of consolidation performance in comparison with the theoretically ideal conditions. Model stone columns are constructed in-flight under 50 times gravity in centrifuge tests and the soil micro-structure in the vicinity of these columns is investigated by applying different methods, including environmental scanning electron microscopy and mercury intrusion porosimetry. The results these tests confirm that smear and disturbance occur owing to stone column installation and the region influenced can be divided into three sections: a penetration zone (1) where the sand particles are squeezed through the clay; a smear zone (2) where the soil particles have experienced a significant reorientation; and a densification zone (3) where the structure of the clay does not appear to change, but compaction of the clay is measurable. The extremes of the disturbed zone around model stone columns are determined to extend to about 2.5 times the column radius.

  • 1366.
    Wersäll, Carl
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Frequency Optimization of Vibratory Rollers and Plates for Compaction of Granular Soil2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Vibratory rollers are commonly used for compaction of embankments and landfills. This task is time consuming and constitutes a significant part of most large construction and infrastructure projects. By improving the compaction efficiency, the construction industry would reduce costs and environmental impact.

    This research project studies the influence of the vibration frequency of the drum, which is normally a fixed roller property, and whether resonance can be utilized to improve the compaction efficiency. The influence of frequency on roller compaction has not before been studied but the concept of resonance compaction has previously been applied successfully in deep compaction of fills and natural deposits.

    In order to examine the influence of vibration frequency on the compaction of granular soil, small-scale compaction tests of sand were conducted under varying conditions with a vertically oscillating plate. Subsequently, full-scale tests were conducted using a vibratory soil compaction roller and a test bed of crushed gravel. The results showed that resonance can be utilized in soil compaction by vibratory rollers and plates and that the optimum compaction frequency from an energy perspective is at, or slightly above, the coupled compactor-soil resonant frequency. Since rollers operate far above resonance, the compaction frequency can be significantly reduced, resulting in a considerable reduction in fuel consumption, environmental impact and machine wear.

    The thesis also presents an iterative equivalent-linear method to calculate the frequency response of a vibrating foundation, such as a compacting plate or the drum of a roller. The method seems promising for predicting the resonant frequency of the roller-soil system and can be used to determine the optimum compaction frequency without site- and roller-specific measurements.

  • 1367.
    Wersäll, Carl
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Influence of Frequency on Compaction of Sand in Small-Scale Tests2013Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Vibratory rollers are commonly used for compaction of embankments and landfills. In a majority of large construction projects, this activity constitutes a significant part of the project cost and causes considerable emissions. Thus, by improving the compaction efficiency, the construction industry would reduce costs and environmental impact. In recent years, rollers have been significantly improved in regard to engine efficiency, control systems, safety and driver comfort. However, very little progress has been made in compaction effectiveness. While the compaction procedure (e.g. layer thickness and number of passes) has been optimized over the years, the process in which the machine compacts the underlying soil is essentially identical to the situation in the 1970s.

    This research project investigates the influence of one crucial parameter, namely vibration frequency of the drum, which normally is a fixed roller parameter. Frequency is essential in all dynamic systems but its influence on the compaction efficiency has not been studied since the early days of soil compaction. Since laboratory and field equipment, measurement systems and analysis techniques at the time were not as developed as they are today, no explicit conclusion was drawn. Frequencyvariable oscillators, digital sensors and computer‐based analysis now provide possibilities to accurately study this concept in detail.

    In order to examine the influence of vibration frequency on the compaction of granular soil, small‐ scale tests were conducted under varying conditions. A vertically oscillating plate was placed on a sand bed contained in a test box. The experiments were carried out in laboratory conditions to maximize controllability. The first test setup utilized an electro‐dynamic oscillator where dynamic quantities, such as frequency and particle velocity amplitude, could be varied in real‐time. The second test setup included two counter‐rotating eccentric mass oscillators, where tests were conducted at discrete frequencies. This type of oscillator has a force amplitude that is governed by frequency.

    The main objectives of the tests were to determine the optimal compaction frequency and whether resonance can be utilized to improve compaction efficiency. Results showed that resonance had a major influence in the electro‐dynamic oscillator tests, where the applied force amplitude is low, and the optimal compaction frequency is the resonant frequency under these circumstances. In the rotating mass oscillator tests, where a high force was applied to the plate, resonant amplification was present but not as pronounced. Since force increase with frequency, the optimal frequency to obtain the highest degree of compaction is very large. In a practical regard, however, frequency should be kept as low as possible to minimize machine wear and emissions while still achieving a sufficient compaction of the soil. Considering the practical issues, it is proposed that surface compactors should operate slightly above the resonant frequency. However, the applicability to vibratory rollers must be confirmed in full‐scale tests.

    The thesis also presents an iterative method to calculate the frequency response of a vibrating plate, incorporating strain‐dependent soil properties. Calculated dynamic quantities are compared to measured values, confirming that the method accurately predicts the response.

  • 1368.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bodare, Anders
    Geo Risk & Vibration Scandinavia.
    Massarsch, Rainer
    Geo Risk & Vibration Scandinavia.
    Frequency content of vertical ground vibrations caused by surface impact2012Konferansepaper (Fagfellevurdert)
  • 1369.
    Wersäll, Carl
    et al.
    Geo Risk & Vibration Scandinavia.
    Bodare, Anders
    Geo Risk & Vibration Scandinavia.
    Massarsch, Rainer
    Geo Risk & Vibration Scandinavia.
    Vibration Source Localization along Railway Tracks2012Inngår i: Noise and Vibration Mitigation for Rail Transportation Systems / [ed] T. Maeda et al., Berlin: Springer, 2012, s. 267-274Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Ground-borne vibration from railway traffic is an increasing problem in urbanized areas and measures are often needed to minimize its effects on the environment. An important question when dealing with railway problems is to identify the source(s) of vibration emitted along the railway track. Once this information is available, it is often possible to mitigate the problem by improving stiffness of the railway track and/or to upgrade worn-out or damaged rail sections and turnouts. This paper describes a method which makes it possible to determine the locations of track sections which are likely to emit strong ground vibration. A purpose-built track-bound vehicle which can be vibrated continuously at different frequencies can identify track sections having unfavorable dynamic foundation conditions. A theoretical concept is proposed to calculate the potential of energy emission from the vehicle moving along the track. Further, an innovative method is presented which makes it possible to determine the location of vibration sources by measurement of ground vibrations from existing railway traffic. This information can be used to determine the location of track sections where remedial measures are needed. Results are presented, illustrating application of the concepts, which can also be applied to other types of vibration problems.

  • 1370.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Influence of force ratio and frequency on vibratory surface compaction2016Inngår i: Geotechnics for Sustainable Infrastructure Development / [ed] Phung Duc Long, 2016Konferansepaper (Fagfellevurdert)
  • 1371.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Small-Scale Testing of Frequency-Dependent Compaction of Sand Using a Vertically Vibrating Plate2013Inngår i: ASTM geotechnical testing journal, ISSN 0149-6115, E-ISSN 1945-7545, Vol. 36, nr 3, s. 394-403Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Vibratory rollers generally operate at a fixed vibration frequency. It is hypothesized that the compaction of soil could be made more efficient if the frequency could be adapted to specific project conditions. In order to study the applicability to surface compaction, the frequency dependence of compacting dry sand with a vertically vibrating plate was investigated experimentally in 85 small-scale tests. Tests were performed in a test box simulating the free-field condition and with concrete underlying the sand bed. The results show that there is a distinct frequency dependence, implying a significantly improved compaction effect close to the compactor soil resonant frequency. It is suggested that particle velocity is the governing amplitude parameter for vibratory soil compaction, rather than displacement or acceleration. As the soil is compacted, it is also displaced, resulting in surface heave. A larger vibration amplitude implies greater displacement relative to the compacted volume. It was also observed that the compaction and strain-dependent reduction of soil stiffness are closely related.

  • 1372.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bodare, Anders
    Dynamic response of vertically oscillating foundations at large strain2014Inngår i: Computer Methods and Recent Advances in Geomechanics - Proceedings of the 14th Int. Conference of International Association for Computer Methods and Recent Advances in Geomechanics, IACMAG 2014 / [ed] Oka, Murakami, Uzuoka & Kimoto, CRC Press, 2014, s. 643-647Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A method for calculating the dynamic response of a vertically oscillating foundation on soil with strain-dependent properties is developed. Strain-dependent stiffness and damping are incorporated by an iterative procedure, presenting the response in frequency domain. The calculated dynamic displacement amplitudes are compared to small-scale tests using a vertically oscillating plate. The calculated dynamic quantities agree well with measured amplitudes over a wide frequency range.

  • 1373.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    Lund Universitet.
    Nordfelt, Ingmar
    Dynapac.
    Frequency Variable Surface Compaction of Sand Using Rotating Mass Oscillators2015Inngår i: ASTM geotechnical testing journal, ISSN 0149-6115, E-ISSN 1945-7545, Vol. 38, nr 2, s. 198-207Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The influence of vibration frequency was studied in 110 small-scale compaction tests conducted using a vertically oscillating plate. The underlying soil was dry sand, or sand close to the optimum water content. The results showed that there is a resonant amplification, providing a slightly higher degree of compaction. Frequency has a major influence on soil compaction. An iterative method for calculating the dynamic response of the plate, incorporating strain-dependent properties of the soil, is also presented. The calculated frequency response agrees fairly well with measured quantities.

  • 1374.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Massarsch, Rainer
    Geo Risk and Vibration Scandinavia AB.
    Soil Heave Due to Pile Driving in Clay2013Inngår i: Sound Geotechnical Research To Practice: Honoring Robert D.Holtz  II / [ed] Armin W. Stuedlein, and Barry R. Christopher, American Society of Civil Engineers (ASCE), 2013, s. 481-499Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Soil heave due to pile driving in clay is discussed and, in particular, its influence on adjacent piles. Finite element studies and results of model tests are presented and compared with field measurements. It is demonstrated that in the vicinity of the driven pile, the soil is displaced mainly in the lateral direction, similar to soil subjected to passive earth pressure. General rules of estimating soil heave inside and outside a pile group are examined. A method is proposed for estimating soil heave when driving a group of piles. Practical application of predicting soil heave is illustrated by an example.

  • 1375.
    Wersäll, Carl
    et al.
    Geo Risk & Vibration Scandinavia.
    Massarsch, Rainer
    Geo Risk & Vibration Scandinavia.
    Bodare, Anders
    Geo Risk & Vibration Scandinavia.
    Planning and Execution of Rock Blasting Adjacent to Tunnels2009Inngår i: Environmental Vibrations: Prediction, Monitoring, Mitigation and Evaluation, VOLS I AND II / [ed] H. Xia & H. Takemiya, 2009, s. 749-756Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Prediction and monitoring of vibrations from rock blasting is of practical importance. Damage to rock tunnels caused by blasting is fundamentally different to that of conventional buildings. Different damage mechanisms are discussed as well as methods to monitor the development of cracks by analysis of frequency content. For the assessment of the damage potential it is essential to understand wave propagation in rock and the dynamic response of cavities to vibration excitation. Vibration frequency and wavelength in relation to the size of the cavity are important parameters. Vibration amplification of a circular tunnel to a plane wave is analyzed and guidelines given for practical design applications. Filtering the vibration signal, which is often required in national standards, car. give misleading results for tunnels in rock.

  • 1376.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Nordfelt, Ingemar
    Dynapac.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Vibrovältar och jorddynamik - mot effektivare packning2013Inngår i: Bygg & teknik, ISSN 0281-658X, nr 1, s. 32-35Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Packning är den vanligaste jordförstärkningsmetoden och används i stort sett i alla byggprojekt. Ökande byggkostnader och striktare utsläppskrav gör att det finns ett behov av att effektivisera packningsprocessen. I ett doktorandprojekt vid Kungliga Tekniska högskolan (KTH) studeras hur jordpackning med vibrovält kan bli mer effektivt genom att ta hänsyn till  amspelet mellan vält och jord samt vältens och jordens dynamiska egenskaper. Projektet  inansieras av Svenska Byggbranschens Utvecklingsfond (SBUF), Dynapac, Peab och KTH och utförs som ett samarbete mellan KTH, Dynapac och Peab.

  • 1377.
    Wersäll, Carl
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Nordfelt, Ingmar
    Dynapac Compaction Equipment AB.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Soil compaction by vibratory roller with variable frequency2016Inngår i: Geotechnique, ISSN 0016-8505, E-ISSN 1751-7656Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Full-scale tests were conducted to study the influence of the operating frequency of a vibratory roller on the compaction of crushed gravel in a controlled environment. Tests were performed at both fixed and variable frequencies. The average densification of the soil was represented by settlement of the ground surface, and depth-dependent density variation before and after compaction was determined by horizontal nuclear density gauge measurements. The resonant frequency was approximately 17 Hz and frequencies in the range 15–35 Hz were tested. The optimum compaction frequency was determined to be around 18 Hz; that is, slightly above resonance, as compared with the standard operating frequency of the roller, 31 Hz. Lower compaction frequency significantly reduces the required engine power and thus fuel consumption and environmental impact, while increasing the lifespan of the roller. Furthermore, the soil closest to the ground surface is loosened at high frequency. This can be avoided with a lower compaction frequency and the need for subsequent static passes can thereby possibly be eliminated.

  • 1378.
    Westberg, Mari
    et al.
    Lund University.
    Johansson, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Possible consequences of deterministic design of concrete dams: a comparison to probabilistic design2010Inngår i: Dam Safety: Sustainability in a Changing Environment, 2010Konferansepaper (Fagfellevurdert)
  • 1379. Westberg, Mari
    et al.
    Johansson, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    System for concrete dam reliability with respect to foundation stability2012Inngår i: Proceedings of the 3rd International Forum on Risk Analysis, Dam Safety Dam Security and Critical Infrastructure Management, 3IWRDD-FORUM, CRC Press, 2012, s. 87-92Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to perform a complete risk analysis of a dam facility, it is necessary to have information about the probability and consequences of failure. To analyze the probability of failure of a concrete dam, all components and all failure modes must be accounted for. This paper presents a methodology for the calculation of the failure probability of a concrete dam with respect to foundation stability where the dam is considered as a system. The system is divided into different levels, where the top event on the "structure level" is failure of the dam. The next level is "monolith level", where each monolith can be considered as an element in a series system of the concrete dam. Below the monolith level is the "failure location level" which describes where the failure occurs, in the concrete-rock contact, in the rock mass or in the concrete. Since it is the weakest of these failure locations that will govern where the failure occurs, each failure location can be seen as elements in a series system. Beneath this level is the "failure mode level" where failure modes such as sliding and rotation also constitute elements in a series system. The "Basic failure modes" are the foundation level in the system. In some situations, the reliability of all failure modes as well as the correlation between failure modes is of importance for the overall reliability. In other situations only the reliability of a dominant failure mode is of importance. A discussion regarding this is given.

  • 1380.
    Westberg Wilde, Marie
    et al.
    ÅF Industry.
    Johansson, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE).
    Analysis of concrete dams based on "Probabilistic model code for concrete dams"2015Konferansepaper (Fagfellevurdert)
  • 1381.
    Westerberg, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Behaviour and modelling of a natural soft clay: triaxial testing, constitutive relations and finite element modelling1999Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main objectives if the research project have been to create an experimental basis for a more general theoretical modelling of Swedish clays and to improve the knowledge of the mechanical behaviour of natural soft clays. Another objective has been to investigate the effects of end restraint on the mechanical behaviour obtained in triaxial tests, by means of numerical simulations. Extensive experimental studies were performed by triaxial tests on a natural soft clay from the city of Norrköping. The results are discussed in detail from a quantitative and qualitative point of view and the effects of the in situ structure of the clay on the mechanical behaviour focused. Undrained and drained shear conditions are investigated. Obtained deformation modes in triaxial tests ar classified and analysed. Soil parameters for constitutive models are evaluated and discussed and requirements formulated for a constitutive model supposed to describe the behaviour of the clay.

  • 1382.
    Westerberg, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Lerors mekaniska egenskaper: experimentell bestämning och kvalitativ modellering med tillämpning på lera från Norrköping1995Licentiatavhandling, monografi (Annet vitenskapelig)
  • 1383.
    Westerberg, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Utmaningar och möjligheter för en förbättrad geoteknik: laboratorieprovning och materialegenskaper idag och imorgon2008Inngår i: Bygg & Teknik, ISSN 0281-658X, nr 1, s. 12-18Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 1384.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Albing, Daniel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Larsson, Rolf
    Swedish Geotechnical Institute.
    Research on strength and deformation properties of Swedish fine-grained sulphide soils2005Inngår i: Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering: Comptes rendus du XVIème Congrès International de Mécanique des Sols et de la Géotechnique : [16 ICSMGE, Osaka, Japan, 12 - 16 September 2005], Rotterdam: Millpress , 2005, Vol. 2, s. 623-626Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A recently started research project concerning strength and deformation properties of Swedish fine-grained sulphide soils is presented. The scope of study is outlined. The overall purpose of the project is to find suitable testing methods in field and laboratory to determine reliably the mechanical properties of fine-grained sulphide soils. In this paper, some test results of undrained shear strength of sulphide soils, determined with different test methods at two test sites, is presented. The results confirm that there is a need for calibration of the different evaluation methods in order to obtain relevant values in fine-grained sulphide soils.

  • 1385.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Albing, Daniel
    Larsson, Rolf
    Swedish Geotechnical Institute.
    Strength and deformation properties of fine-grained sulphide soil2005Inngår i: Proceedings: XVI ICSMGE Osaka 2005, Rotterdam: Millpress , 2005, s. 623-636Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Sulphide soil is the dominating fine-grained soil type along the east coast of the northern part of Sweden. A sulphide soil typically consists of clay and silt fractions with various and smaller content of sand. Sulphide soil may contain high amounts of iron mono sulphides (FeS) and organic content up to about 10%. A fine-grained sulphide soil normally shows low strength and high compressibility. Previous research concerning strength and deformation properties of Swedish fine-grained soils has very little included sulphide soil. It has been found that field and laboratory methods used to determine properties of other fine-grained soils, are often not suitable for sulphide soil.In this paper results from field and laboratory testing of fine-grained sulphide soil are presented and discussed. In the field, field vane tests, CPT-tests, dilatometer tests, seismic CPT-tests and undisturbed sampling are conducted. In the laboratory, triaxial tests, direct shear tests, oedometer tests, CRS-oedometer tests, routine tests of basic geotechnical properties and tests to determine chemical properties are done. In the laboratory, testing is carried out in room temperature as well as for in situ soil temperature for samples handled either at normal air conditions or at air free conditions.The main purpose of the research project is to find suitable testing methods in field and laboratory to determine mechanical properties of fine-grained sulphide soils. This includes how the results should be interpreted and evaluated and how samples should be sampled, transported, stored, handled and tested. In the paper the first part of the project is reported, including comparisons between properties and parameters determined in field and in laboratory. Effects on mechanical properties of testin g in room temperature versus in situ soil temperature and effects of handling the sample at air free conditions or not, are presented.

  • 1386.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Andersson, Mattias
    SGI/LTU.
    Undrained shear strength and compression properties of Swedish fine-grained sulphide soils2009Inngår i: Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: the academia & practice of geotechnical engineering : 5-9 October 2009, Alexandria, Egypt = Comptes rendus du 17ème Congrès International de Méchanique des Sols et d'ingénierie Géotechnique : Le monde universitaire et la pratique en géotechnique : 5-9 Octobre 2009, Alexandrie, Egypte / [ed] M. Hamza; M. Shahien; Y. El-Mossallamy, Amsterdam: IOS Press, 2009, Vol. 1, s. 72-75Konferansepaper (Fagfellevurdert)
  • 1387.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Edeskär, Tommy
    Gummiklipp: ett alternativt konstruktionsmaterial2001Inngår i: V-byggaren : väg- och vattenbyggaren, ISSN 0283-5363, nr 4, s. 38-39Artikkel i tidsskrift (Annet vitenskapelig)
  • 1388.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mácsik, Josef
    LTU.
    Laboratorieprovning av gummiklipps miljögeotekniska egenskaper2001Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med denna undersökning var att bestämma tekniska och miljötekniska egenskaper hos gummiklipp. Med detta som underlag har en miljögeoteknisk bedömning utförts avseende användning av materialet som lättfyllnad i vägbankar och dränering i askdeponier. Vidare identifieras typiska och dimensionerande värden på tekniska och miljötekniska parametrar. Genom laboratorieförsök har de tekniska egenskaperna kompression, densitet, permeabilitet och skjuvhållfasthet undersökts för gummiklipp med storleken 50x50 mm2. En nyutvecklad "multiapparat" med diametern 64 cm och initiella provhöjden 40-60 cm har använts för försöken. Vad avser hållfasthetsegenskaper har även gummigranulat med storleken 1-3 mm och 0-12 mm provats i en konventionell direkt skjuvapparat. Miljötekniska egenskaper har undersökts för gummiklipp med avseende på innehåll och lakbarhet av metaller, svavel och polyaromatiska kolväten (PAH). Sammantaget gäller att materialet, med avseende på undersökta egenskaper, bedöms ha goda förutsättningar att dels kunna nyttjas som ett lättfyllnadsmaterial exempelvis vid kompensationsgrundläggning eller som ett kombinerat lättfyllnads- och tjälisoleringsmaterial och dels kunna nyttjas som ett dräneringsmaterial i botten på en askdeponi.

  • 1389.
    Westerberg, Bo
    et al.
    Swedish Geotechnical Institute, Linköping, Sweden.
    Müller, Rasmus
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik. Tyréns AB, Sweden.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Evaluation of undrained shear strength of Swedish fine-grainedsulphide soils2015Inngår i: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917, Vol. 188, s. 77-87Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In Swedish practice, there is a long tradition of evaluating undrained shear strength from fall-cone tests and field vane tests. During the last 20 years cone penetration tests have also become widely used. However, the results from all these test methods have to be evaluated using empirical factors. The factors generally used for Swedish clays are related to liquid limit and overconsolidation, but they are not applicable to all types of fine-grained soils and can often be improved by local calibration for the particular type of soil in the area of current interest. For this calibration, the results of direct simple shear tests and/or triaxial tests in the laboratory are normally used. This paper presents an evaluation for Swedish fine-grained sulphide soils, for which a general correction factor of 0.65 for field vane tests and fall-cone tests, a cone factor Nkt of 20.2 for cone penetration tests and a relation cu,DSS/(σ′cOCR−0.2) of 0.28 have been found. No correlations were found between these empirical factors and the clay content, liquid limit or organic content, but a relationship was found between the overconsolidation ratio and both the cone penetration test and the field vane test. The sulphide soils in question are found in northern Sweden along the coast of the Gulf of Bothnia. They aremostly classified as organic silt or organic clay,which is normally silty.

  • 1390. Westerberg, Bo
    et al.
    Pousette, Kerstin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rogbeck, Yvonne
    SGI.
    Andersson, Mattias
    SGI.
    Norrman, Tomas
    Ramböll Sverige.
    Laboratory tests of stabilised sulphide soil from Northern Sweden2005Inngår i: Deep mixing '05: International Conference on Deep Mixing : best practice and recent advances, Swedish Deep Stabilization Research Centre , 2005Konferansepaper (Annet vitenskapelig)
  • 1391.
    Westerberg, Bo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Viklander, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ballastrening och bankettrensning på Malmbanan: en fält- och laboratoriestudie2001Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med studien var dels att bestämma tekniska egenskaper(kornfördelning, densitet, vattenkvot, infiltrationskapacitet, permeabilitet, kapillaritet) hos ballast och bankettens överskottsmassor genom fältförsök och genom laboratorieförsök och dels att baserat på bestämningen av de tekniska egenskaperna hos ballast och bankettens överskottsmassor undersöka behovet av och nyttan med ballastrening och bankettrensning. I studien har förhållandena i fyra sektioner längs Malmbanan, två på vardera sträckan Ljuså-Gransjö och Nattavaara-Kilvo, undersökts genom fältförsök och laboratorieförsök. Av de slutsatser som dragits i studien kan följande nämnas: Det nuvarande kriteriet (dvs när andelen partiklar, d<31.5 mm, överstiger 40 viktsprocent) för när ballastrening skall utföras bör ifrågasättas. Även andra faktorer (kriterier) än andelen partiklar mindre än 31.5 mm bör tas i beaktande för att avgöra när behov av rening finns. Sådana faktorer skulle kunna vara infiltrationskapacitet, porfyllnadsgrad (volymandelen finkornigt material i porutrymmet mellan makadamstenarna), tjällyftningsbenägenhet, dynamiska egenskaper, underballastens beskaffenhet, etc. Flera eller andra siktgränser (än 31.5 mm) och krav på maximal tillåten andel skulle kunna införas. Dessa gränser skall då baseras på olika egenskaper hos ballasten som kan förändras på ett negativt sätt vid en för hög halt av finkornigt material. Baserat på de faktorer som undersökts i denna studie kan konstateras att ballastrening var nödvändig att utföra för att skapa tillräcklig tjocklek på makadamballast och för att rena den nedre delen av ballasten men troligen inte nödvändig med tanke på dräneringsförmåga och tjälfarlighet. Baserat på de faktorer som undersökts i denna studie kan konstateras att bankettrensning var nödvändig att utföra för att ta bort stora mängder onyttiga överskottsmassor, vilket bl a medför att stabiliteten för banvallen ökar, men troligen inte nödvändigt med tanke på dräneringsförmåga och tjälfarlighet.

  • 1392.
    Wetterheim, Hanna
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Byggnadsteknik.
    Josefsson, Hiba
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Byggnadsteknik.
    Sulfidjord – En analys av förbelastning och vertikaldränering med förbelastning2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Syftet med detta examensarbete är att undersöka två olika grundförstärkningsmetoder på sulfidjord, vertikaldränering med förbelastning samt förbelastning, och komma fram till vilken metod som är lämpligast med avseende på sättningar, portryck och hållfasthet. Anledningen till detta arbete är att sulfidjord har dålig bärighet och är sättningsbenägen, vilket gör det till en nödvändighet att förstärka jorden innan byggnation. Sulfidjord har dålig miljöpåverkan vid kontakt med syre och ska inte grävas upp. Därför är de två förbelastningsmetoderna bra att använda på denna typ av jord. I Sverige finns jorden främst längs Norrlandskusten, vilket är det område som rapportens undersökningar kommer från.Datainsamlingsmetoderna som legat till grund för arbetet har huvudsakligen samlats in genom kvalitativa insamlingsmetoder i form av litteraturstudier av tidigare forskningsarbeten samt intervju med sakkunnig geotekniker. Genom dokumentanalys har kvantitativ insamlingsmetod använts, då insamling av mätvärden från undersökningar genomförts för att ta fram ett resultat.Resultatet sammanställdes och visade att vertikaldränering med förbelastning är en mer optimal förstärkningsmetod att utgå från, utifrån de faktorer som har undersökts. Vid vertikaldränering med förbelastning går tidsförloppet fortare för sättningar och protrycksutjämning. De olika försöken har sammanställts i tabell och ett resultat kunde fås.De skrivna frågeställningarna som behandlades och besvarades i rapporten visade på att vertikaldränering har en snabbare inverkan. Tid kan sparas om metoden väljs och byggnation kan därefter göras på den styvare jorden. Denna rapport har begränsats då den bara behandlar två specifika förstärkningsmetoder. Ekonomiska aspekter och miljöpåverkan tas inte med i rapporten för att inte riskera att ämnet blir stort. Nyckelord: förbelastning, förstärkningsmetoder, sulfidjord, vertikaldränering och överlast.

  • 1393.
    Wibling, Anna
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för naturvetenskap, lantmäteri- och maskinteknik.
    Olsson, Marie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för naturvetenskap, lantmäteri- och maskinteknik.
    Mindre avvikelse i detaljplan enligt fastighetsbildningslagen: En jämförande studie mellan det statliga och det kommunala lantmäteriet2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete behandlar begreppet ”mindre avvikelse” inom detaljplan. I 3 kap. 2 § fastighetsbildningslagen, FBL återfinns definitionen av när en sådan avvikelse får göras och syftar till fastighetsbildningsåtgärderna fastighetsreglering, sammanläggning, klyvning samt avstyckning. Åtgärder som dessa medförande mindre avvikelse inom detaljplan eller områdesbestämmelser kan ske endast om det inte är i strid mot plan och är förenliga med dess syfte.

    En mindre avvikelse tillkommer genom en slutförd lantmäteriförrättning där lantmäteriet är sista instans och har ansvar för att besluta om den mindre avvikelsen bör godtas eller ej. Syftet med examensarbetet är att belysa eventuella olikheter mellan statligt och kommunalt lantmäteri i förhållande till slutförda förrättningar där mindre avvikelse inom detaljplanelagt område gjorts. Vidare har vi undersökt vad dessa skillnader kan bero på och vad som kan göras för att minska antalet avvikelser inom detaljplanelagt område. Underlag för denna studie har varit förrättningsakter från Göteborgs kommunala lantmäteri, inkomna och slutförda under en tvåårsperiod samt från Kungsbackas och Eskilstunas statliga lantmäterier, inkomna och slutförda under en fyraårsperiod. Sammanlagt har vi gått igenom 2099 förrättningsakter med fastighetsbildningsåtgärder där 551 stycken berörde 3 kap. 2 § FBL samt var belägna inom detaljplanelagt område. Av dessa var det i sin tur sammanlagt 49 stycken som innehöll en mindre avvikelse. Denna studie visar att det oftare förekommer mindre avvikelser i förrättningar handlagda inom det statliga lantmäteriet. Detta beror huvudsakligen på att det statliga lantmäteriet inte har samma möjligheter att medverka i planprocessen i samma utsträckning som den kommunala lantmäterimyndigheten. För att minska antalet mindre avvikelser från detaljplan är ett tätare samarbete mellan dem som upprättar planerna och lantmäteriet som genomför dem, en bra utgångspunkt. Det är också viktigt att lantmäteriet inte godtar förrättningar som resulterar i mindre avvikelse, vilket gör att antalet mindre avvikelser minskar. Om mer arbete läggs på genomförandefrågorna när detaljplanen upprättas kommer det leda till ett snabbare genomförande. Ett snabbt genomförande innebär kortare handläggningstid för  förrättningslantmätaren, vilket är en fördel för fastighetsägaren som är den som får betala för fastighetsbildningsförrättningen 

  • 1394.
    Widenfalk, Lennart
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Håkansson, S.
    Luleå tekniska universitet.
    Mercury, an indicator of sources of ore-bearing boulders ( Sweden).1983Inngår i: Geologiska föreningens i Stockholm förhandlingar, ISSN 0016-786X, Vol. 105, nr 2, s. 155-159Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mercury content of sulfides shows a regular trend on both local and regional scale in the Skellefte district. For this reason sulfide concentrates from thirteen ore boulders were analyzed for Hg, Zn and Cu. The ratio Hg/Zn in sphalerite and Hg/Cu in chalcopyrite as well as the amount of mercury in pyrite appear to serve well as fingerprints of the boulders

  • 1395.
    Wikberg, Per-Olov
    et al.
    Swedish Environmental Protection Agency.
    Palmgren, Petter
    Swedish Environmental Protection Agency.
    Hallberg, Nils
    Swedish Environmental Protection Agency.
    Mårtensson, Stefan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordlund, Daniel
    New Republic Communication Consultants.
    Changes in Attitudes To Risk and Knowledge About Avalanches Among Swedish Skiers After The Introduction of a National Avalanche Safety Program2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In 2013, a web survey was conducted together with Freeride.se, aimed towards Swedish off-piste skiers in order to identify the target group's knowledge, experience and attitudes towards off-piste skiing and avalanches. 1047 skiers participated. The results of the survey gave new important knowledge about different target groups prior to the start of the Swedish avalanche forecast program and also more knowledge regarding the level of avalanche awareness among skiers in general. In 2016 Sweden launched the first national avalanche forecasting program and the same year, a revised avalanche education program was developed and presented. Both constitute important tools for prevention of future avalanche accidents among Swedish skiers. In April 2017, a repetition of the first survey was initiated, with nearly the same questionnaire, to see if there had been any change in behavior, attitudes to risk and knowledge about avalanche awareness among Swedish skiers since 2013. With 1028 participants, the results of the new survey showed some interesting changes that probably could be seen as early effects of the introduction of a new public avalanche forecasting service together with the revised avalanche education program.

  • 1396. Wiklund, J.
    et al.
    Rahman, Mashuqur
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Håkansson, U.
    In-line rheometry of micro cement based grouts - a promising new industrial application of the ultrasound based uvp plus pd method2012Inngår i: Applied Rheology, ISSN 1430-6395, E-ISSN 1617-8106, Vol. 22, nr 4, s. 42783-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Measurements of the viscosity of non-Newtonian fluids and suspensions having a solid volume fraction of about 30% or more is of major interest from an industrial point of view. Cement paste and cement grouts for injection grouting applications, with water to cement ratios typically in the range of 0.4 and 0.6 - 0.8 by weight, are two examples of industrial fluid systems. Few in-line techniques are available on the market that can be used for these fluid systems and under realistic field conditions. The so-called UVP+PD in-line rheometry method combining the Ultrasound Velocity Profiling (UVP) technique with Pressure Difference (PD) measurements is a promising new tool for industrial applications. This paper presents an initial pre-study that aims to demonstrate the feasibility of the UVP+PD method using cement grouts for process monitoring and control of grouting applications under realistic field conditions. The UVP+PD method was tested and found successful for continuous inline measurements of concentrated micro cement-based grouts with water/cement ratios of 0.6 and 0.8. The test set-up consisted of a combination of an experimental " flow loop" and a conventional field grouting rig - UNIGROUT, from Atlas Copco. The rheological properties were determined, directly in-line and the parameters obtained were subsequently compared with off-line measurements using a conventional rotational rheometer.

  • 1397. Wiklund, Johan
    et al.
    Rahman, Mashuqur
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Håkansson, Ulf
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    In-line rheometry of dense cement suspensions using an Ultrasonic Velocity Profiling with combined Pressure Difference Method (UVP-PD)2011Inngår i: Applied Rheology, ISSN 1430-6395, E-ISSN 1617-8106Artikkel i tidsskrift (Annet vitenskapelig)
  • 1398. Wilde, Marie Westberg
    et al.
    Johansson, Fredrik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    System Reliability of Concrete Dams with Respect to Foundation Stability: Application to a Spillway2013Inngår i: Journal of Geotechnical and Geoenvironmental Engineering, ISSN 1090-0241, E-ISSN 1943-5606, Vol. 139, nr 2, s. 308-319Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Structural reliability analysis is not widely used for the design and assessment of concrete dams. In this paper, the system reliability of a spillway structure consisting of two monoliths is calculated. Limit state functions are defined from the failure modes sliding in the concrete rock contact, sliding in the rock mass, and adjusted overturning. Random variables in the limit state functions are defined by stochastic distributions. These are defined based on site investigations and laboratory tests from samples taken at the dam. Simulations and information from the literature are used for the remaining variables. The safety index is calculated by the first-order reliability method for each failure mode and monolith, and the system reliability is approximated by direct integration of the bivariate normal distribution. The output is the safety index including associated sensitivity values at the single failure mode, monolith, and system levels. The results show that the system safety is governed by a persistent rock joint beneath one monolith. A system reliability analysis is found to be a useful tool in the dam risk management process as it can be used to calculate the probability of failure and to identify important failure modes and variables.

  • 1399.
    With, Christoffer
    et al.
    KTH, Tidigare Institutioner, Byggvetenskap. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bahrekazemi, Mehdi
    KTH, Tidigare Institutioner, Byggvetenskap. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bodare, Anders
    KTH, Tidigare Institutioner, Byggvetenskap. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Mätningar av tåginducerade markvibrationer i Kåhög före och efter motåtgärd2004Konferansepaper (Annet vitenskapelig)
  • 1400.
    With, Christoffer
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bahrekazemi, Mehdi
    Golder Associates AB, S-10460 Stockholm, Sweden .
    Bodare, Anders
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Wave barrier of lime-cement columns against train-induced ground-borne vibrations2009Inngår i: Soil Dynamics and Earthquake Engineering, ISSN 0267-7261, E-ISSN 1879-341X, Vol. 29, nr 6, s. 1027-1033Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a comparison between measured train-induced ground vibrations in the free-field before and after countermeasures had been taken at Kahog near Gothenburg in Sweden. A wave barrier of lime-cement columns was constructed parallel to the railway in order to reduce the ground-borne vibrations inside nearby buildings. On top of the barrier an embankment was built to reduce air-borne vibrations. Due to the wave barrier design, part of the energy content of the waves was expected to be reflected by the screen and transmitted energy was expected to be partly scattered. Contribution from the noise-embankment was not thought likely but could not be ruled out due to its fairly large mass and its close proximity to the railway. The effect of the mitigating measures resulted in a 67% reduction of the maximum particle velocity at 30 m and 41% at 60 m from the railway. A simple two-dimensional finite element model has been used to Study the relative importance of the wave barrier and the noise-embankment as contributors to the mitigation recorded of the ground vibrations in the field. It is concluded with respect to ground vibrations that both the barrier and the embankment had a mitigating effect but that the contribution from the barrier dominated. Furthermore, it is seen from the field results as well as the Simulation that the effect of the mitigating action is reduced with increasing distance from the railway.

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