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  • 301.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Stress-strain relationships for silty soils1979Inngår i: Mechanisms of deformation and fracture: proceedings of the interdisciplinary conference held at the University of Luleå, Luleå, Sweden, September 20-22, 1978 / [ed] Kenneth E. Easterling, Oxford: Pergamon Press, 1979, 343-350 s.Konferansepaper (Fagfellevurdert)
  • 302.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Stress-strain relationships for silty soils1978Rapport (Annet vitenskapelig)
  • 303.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Water flow and swelling pressure in non-saturated bentonite-based clay barriers1985Inngår i: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917, Vol. 21, nr 3-4, 229-237 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The water uptake of 10 and 20% bentonite-sand mixtures and of 100% pure bentonite was studied experimentally. The results were compared with calculated water content distributions to study the usefulness of the diffusion equation. The relation between the swelling pressure and the degree of saturation of a bentonite was also studied.

  • 304.
    Börgesson, Lennart
    et al.
    Luleå tekniska universitet.
    Axelsson, Kennet
    Luleå tekniska universitet.
    Stress-strain-strength behaviour and its modelling for silty soils1980Rapport (Annet vitenskapelig)
  • 305.
    Caprez, M.
    et al.
    ETH, Zürich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    ETH, Zürich.
    Steiger, F.
    ETH, Zürich.
    Testing of TBM excavation material in sandstone and marl for reuse in embankments or as fill2001Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Several tunnels in geological formations of molasse, marl or sandstone are planned or are presently under construction in Switzerland. The excavation of these tunnels is very often carried out by tunnel boring machines (TBM). This kind of excavation tends to produce lamellar excavation materials (chips). For the reuse of these materials in road embankments etc., there are certain disadvantages concerning the compression properties. Limiting deformation will be the main restriction on design in the reuse of this material and this is manifested also in terms of the possible changes of volume as a function of time. On the one hand, volume may increase due to instability in relation to water and possibly frost, whereby swelling occurs. On the other hand, volume may decrease due to repeated dynamic loading. Inevitably these volume changes will not occur to the same degree and within the same timeframe. The material can be stabilised by using a variety of cementing agents to improve the key properties. A range of laboratory experiments were performed to find the optimal mixture to be used as a base to the reinforced concrete slabs, which formed the railbed to the major railway line passing through this tunnel. An experimental field test was carried out using this specific mixture to confirm the suitability in relation to the construction method proposed and the properties measured at full scale.

  • 306.
    Carling, Kenneth
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Håkansson, Johan
    Högskolan Dalarna, Akademin Industri och samhälle, Kulturgeografi.
    Jia, Tao
    School of Remote Sensing and Information Engineering, Wuhan University.
    Out-of-town shopping and its induced CO2-emissions2013Rapport (Annet vitenskapelig)
    Abstract [en]

    Planning policies in several European countries have aimed at hindering the expansion of out-of-town shopping centers. One argument for this is concern for the increase in transport and a resulting increase in environmental externalities such as CO2-emissions. This concern is weakly founded in science as few studies have attempted to measure CO2-emissions of shopping trips as a function of the location of the shopping centers. In this paper we conduct a counter-factual analysis comparing downtown, edge-of-town and out-of-town shopping. In this comparison we use GPS to track 250 consumers over a time-span of two months in a Swedish region. The GPS-data enters the Oguchi’s formula to obtain shopping trip-specific CO2-emissions. We find that consumers’ out-of-town shopping would generate an excess of 60 per cent CO2-emissions whereas downtown and edge-of-town shopping centers are comparable.

  • 307.
    Carling, Kenneth
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Håkansson, Johan
    Högskolan Dalarna, Akademin Industri och samhälle, Kulturgeografi.
    Jia, Tao
    School of Remote Sensing and Information Engineering, Wuhan University.
    Out-of-town shopping and its induced CO2-emissions2013Inngår i: Journal of Retailing and Consumer Services, ISSN 0969-6989, E-ISSN 1873-1384, Vol. 20, nr 4, 16 s.382-388 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Planning policies in several European countries have aimed at hindering the expansion of out-of-town shopping centers. One argument for this is concern for the increase in transport and a resulting increase in environmental externalities such as CO2-emissions. This concern is weakly founded in science as few studies have attempted to measure CO2-emissions of shopping trips as a function of the location of the shopping centers. In this paper we conduct a counter-factual analysis comparing downtown, edge-of-town and out-of-town shopping. In this comparison we use GPS to track 250 consumers over a time-span of two months in a Swedish region. The GPS-data enters the Oguchi’s formula to obtain shopping trip-specific CO2-emissions. We find that consumers’ out-of-town shopping would generate an excess of 60 per cent CO2-emissions whereas downtown and edge-of-town shopping centers are comparable.

  • 308.
    Carlsson, Mats
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Management of geotechnical risks in infrastructure projects: an introductory study2005Licentiatavhandling, monografi (Annet vitenskapelig)
  • 309.
    Carlsson, Torbjörn
    Luleå tekniska universitet.
    Interactions in MX-80 bentonite/water/electrolyte systems1986Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main objective of this work was to study the influence of temperature, water ratio and electrolyte content on the molecular water mobility in water saturated MX-80 bentonite. T a minor extent the influence of pressure, time, and specific surface area on the molecular water mobility was studied. The investigation was carried out by pulsed nuclear magnetic resonance technique, NMR. The proton T2 relaxation time was chosen as a measure of the molecular water mobility. The investigated samples consisted of MX-80 bentonite to which water solutions of either NaCl, KCl, CaCl2, or SrCl2 were added. The electrolyte concentration varied between 0 and 0.35 mol.dm-3. The water ratio varied between 23 and 2000 per cent. The electrolyte content and water ratio were kept within limits corresponding to non-flocculated MX-80 bentonite. The sample temperature varied between +15 and +80°C. The structure of montmorillonite, the main component in MX-80 bentonite, and the structure of liquid water as well as the main physico-chemical interactions taking place in the investigated MX-80 bentonite samples are discussed.

  • 310.
    Carlsson, Torbjörn
    Luleå tekniska universitet.
    NMR-studies of pore water in bentonite/water/electrolyte1986Inngår i: Scientific basis for nuclear waste management IX: symposium held September 9-11, 1985, Stockholm, Sweden / [ed] Lars O. Werme, Pittsburgh, Pa: Materials Research Society, 1986, 609-615 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The properties of water saturated bentonite systems are highly dependent on the pore water chemistry, water content and temperature. In this study relative changes in the physical state of pore water are studied by means of the nuclear magnetic resonance technique (NMR). It is found that the relative water mobility increases with increasing water content and/or increasing temperature, while an increase in the electrolyte content lowers the water mobility

  • 311.
    Carlsson, Torbjörn
    et al.
    Luleå tekniska universitet.
    Jacobsson, Arvid
    Luleå tekniska universitet.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ofruset vatten i frusen jord: exempel på praktikansluten grundforskning vid avdelningen för geoteknik vid högskolan i Luleå.1982Inngår i: Väg- och Vattenbyggaren, ISSN 0042-2177, nr 1, 33-35 s.Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 312.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Kamaleddin, Suhair
    Iraqi Ministry of Housing & Construction, National Center for Construction Laboratories and Research Babylon, Baghdad.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Soil Characteristics in Selected Landfill Sites in theBabylon Governorate, Iraq2017Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 11, nr 4, 348-363 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Babylon Governorate is situated in the middle of Iraq. It covers an area of 5,315 km

    2 and has 2,092,998 inhabitants distributed throughout its five major cities (Qadhaa). Presently, there is no landfill site in the governorate that meets the environmental criteria for the disposal of municipal and industrial waste. Consequently, GIS (geographic information system) and methods of multi-criteria decision making were used here to select the best sites in each city in the Babylon Governorate that would fulfil the environmental requirements. Two sites were chosen in each city. As the groundwater is very shallow in this area, the design should ensure against groundwater pollution by leachate from these sites. To avoid this problem, soil investigation was conducted at these sites so that the most suitable landfill design could be accomplished. The results of soil investigation in these sites include the soil profile, groundwater depth, chemical properties, allowable bearing capacity, Atterberg limits test results and material characteristics of the soil strata. From the research, it is believed that the best design is one that puts the landfill above ground.

  • 313.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of ScienceUniversity of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    GIS-based assessment of combined AHP and SAW methods for selecting suitable sites for landfill in Al-Musayiab Qadhaa, Babylon, Iraq2017Inngår i: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 76, nr 5, 209Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Selecting a landfill site is a difficult task because the process depends on many factors and restrictions. Landfill is an optimal solution for the disposal of solid waste in Al-Musayiab Qadhaa, which is located in the northern part of Babylon Governorate. At the moment, there is no landfill site in that area that follows the scientific selection site criteria. For this reason, in this research, fifteen variables were considered (groundwater depth, rivers, soil types; agriculture lands use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centers, villages and archeological sites) using geographic information system (GIS) to find out the best suitable landfill site. In addition, two methods of multi-criteria decision-making were used to derive weights for criterion’s maps on GIS to obtain potential landfill sites. The first method is analytical hierarchy process (AHP) which was used to identify the weight for each criterion from the matrix of pairwise comparisons. The second method was the simple additive weighting (SAW) which is a simple method to solve the problem of the selection landfill sites. After comparison of the results obtained based on combining two final maps resulted from methods of AHP and SAW using GIS environment to determine the pixels percentage of matching and non-matching for two maps, two suitable candidate landfill sites were identified that satisfy the requirements with an area of 7.965–5.952 km2. Area of these sites can accommodate the solid waste generated from the Qadhaa up to 2030.

  • 314.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, College of Science, Kufa University.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Sites Selection Using AnalyticalHierarchy Process and Ratio ScaleWeighting: Case Study of Al-Mahawil,Babylon, Iraq2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 2, 123-141 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Selecting a landfill site is an optimal solution for the disposal of solid waste inAl-Mahawil Qadhaa, both to fulfill the environmental and scientific requirements,and to comply with regulations and restrictions in this Qadhaa. Presently,there is no landfill site in the area that meets the scientific site selection criteria.Therefore, in this study, two methods of multi-criteria decision-makingand Geographic Information System (GIS) were used to produce a map ofcandidate sites for landfill. Fifteen criteria were entered within GIS: groundwaterdepth, rivers, soil types; agriculture lands use, land use, elevation, slope,gas pipelines, oil pipelines, power lines, roads, railways, urban centers, villagesand archaeological sites. The Analytical Hierarchy Process (AHP) is the firstmethod that was applied to derive criteria weightings using the matrix of pairwisecomparisons. The second method was the Ratio Scale Weighting (RSW),which is based on experts’ opinion, in order to identify the criteria weightingsby giving a ratio score value for each criterion relative to the other criteria.Accuracy assessment (Kappa and Overall Assessment) methods were used tocompare the two raster maps which resulted from the two models, and to determinethe percentage value of matching pixels for the two maps. Two suitablecandidate sites for landfill were identified that satisfy the requirementswith an area of 2.218 km2 - 2.950 km2 in order to accommodate the solidwaste generated from the Qadhaa in the period 2020 to 2030.

  • 315.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Present Status of Solid Waste Management at Babylon Governorate, Iraq2015Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 7, 408-423 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Babylon Governorate covers an area of 5315 km2 with a population that reaches about 1,974,490 inhabitants in the central part of Iraq. Iraq produced 31,000 tons/day solid waste in 2013. The Governorate of Babylon produces annual 483,221 tons of solid waste. Management of collection and disposal of waste in Babylon Governorate is done through open dumping of waste and poor collection process. These sites do not conform to the scientific and environmental criteria applied in the selection of landfill sites. To find out how much solid waste is expected in the future, two methods were used to calculate the population growth in Babylon Governorate to the year 2030. The results showed that the total waste in 2030 will be 761,104 tons and 943055 tons while the cumulated quantity of solid waste expected till 2030 was 12,494,521 tons and 14,095,437 tons according to the first and second methods respectively.

  • 316.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Sitting by Two Methods in Al-Qasim, Babylon, Iraq and Comparing Them Using Change Detection Method2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 8, 723-737 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The selecting of a site for landfill is considered as a difficult process because many criteria should be involved. The main aim of establishing a landfill is to protect the human and environment. Al-Qasim district is considered as the study area in this work. It is one of the main districts in Babylon Governorate, Iraq. There is no systematic site as landfill that fulfil the environmental and scientific criteria in this area. Therefore, the most important fifteen criteria that suited the environmental requirements were selected in the current study. These criteria are: groundwater depth, urban centers, rivers, villages, soil types, elevation, roads agricultural land use, slope, land use, archaeological sites, power lines, gas pipelines, oil pipelines and railways. Two methods of multi criteria decision making AHP (analytical hierarchy process) and SRS (straight rank sum) were applied to obtain the weights of criteria in dissimilar styles. The raster maps of the selected criteria were prepared and analyzed within the GIS software. Then, the change detection method was implemented to compare the two output raster maps resulted from AHP and SRS methods. Two appropriate candidate sites for landfill were selected to accommodate the cumulative solid waste until the year 2030 in Qasim district. The areas of these sites were 2.766 km2 and 2.055 km2 respectively.

  • 317.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill site selection using geographic information system and analytical hierarchy process: A case study Al-Hillah Qadhaa, Babylon, Iraq2016Inngår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 34, nr 5, 427-437 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Al-Hillah Qadhaa is located in the central part of Iraq. It covers an area of 908 km2 with a total population of 856,804 inhabitants. This Qadhaa is the capital of Babylon Governorate. Presently, no landfill site exists in that area based on scientific site selection criteria. For this reason, an attempt has been carried out to find the best locations for landfills. A total of 15 variables were considered in this process (groundwater depth, rivers, soil types, agricultural land use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centres, villages and archaeological sites) using a geographic information system. In addition, an analytical hierarchy process was used to identify the weight for each variable. Two suitable candidate landfill sites were determined that fulfil the requirements with an area of 9.153 km2 and 8.204 km2. These sites can accommodate solid waste till 2030

  • 318.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Siting Using GIS and AHP (Analytical Hierarchy Process): A Case Study Al-Qasim Qadhaa, Babylon, Iraq2016Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 5, 530-543 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The selection of a landfill site is considered as a complicated task because this process is based on many factors and restrictions. For Al-Qasim Qadhaa, which is situated in the southern part of the Babylon Governorate, Iraq, there is no landfill site in that area that conforms to the scientific criteria for selecting sites for landfill. For this reason, 15 criteria were adopted in this study (groundwater depth, rivers, soil types, agriculture lands use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centers, villages and archaeological sites) using GIS (geographic information system), which has a large ability to manage input data. In addition, the AHP (analytical hierarchy process) method was used to derive the relative weightings for each criterion using pair-wise comparison. To obtain the suitability index for candidate landfill sites, a weighted linear combination method was used. After combining these methods, two suitable candidate landfill sites, with areas of 2.766 km2 and 2.055 km2, respectively, were found to satisfy the scientific and environmental requirements. The area of these sites can accommodate solid waste from 2020 until 2030 based on the required area, which was 0.702 km2.

  • 319.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Combining GIS Applications and Method of Multi-Criteria Decision-Making (AHP) for Landfill Siting in Al-Hashimiyah Qadhaa, Babylon, Iraq2017Inngår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, nr 11, 1932Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Landfill siting is a complex process. It is one of the major problems in waste management, where many factors should be taken into consideration when selecting a suitable site for landfill in any given area. At the present time, there are many random waste disposal sites distributed throughout Al-Hashimiyah Qadhaa in Iraq. In this study, the Geographic Information System (GIS) and the Analytical Hierarchy Process (AHP) were used to select the best sites for landfill. The process of selecting sites for landfill in Al-Hashimiyah Qadhaa comprised two steps. First, fifteen different criteria were mapped and incorporated into overlay analyses within GIS software to produce the final suitability index map for the site. The second step comprises the exclusion of unsuitable areas from the final map to simplify identification of the candidate sites for landfill in the study area. The weightings of criteria were identified using AHP, and the weightings of the sub-criteria of each criterion were determined based on multiple factors. In order to accommodate solid waste from 2020 until 2030, two suitable candidate landfill sites were determined which fulfill the required area of 1.013 km2 with areas of 1.374 km2 and 1.288 km2 respectively.

  • 320.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussein, Hussein M.
    Luleå tekniska universitet.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfills Site Selection in Babylon, Iraq2017Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 7, nr 4, 1-15 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Babylon Governorate is located in the middle of Iraq and includes five major districts called Qadhaa. It occupies an area of 5315 km2 with population of 2,092,998 in 2015. The process of selecting landfill site is considered complicated task related to many factors and regulations. Currently, there is no landfill site in Babylon Governorate that fulfils the scientific and environmental criteria. Therefore, in this study fifteen of suitable criteria were selected. These criteria are: groundwater depth, urban canters, rivers, villages, soil types, elevation, agriculture, roads lands use slope, land use, archaeological sites, power lines, gas pipelines, oil pipelines and railways. Then these criteria were used in the GIS (geographic information system), which has a high ability to manage and analyse various data. In addition, the AHP (analytical hierarchy process) method was used to derive the weightings of criteria through using a matrix of pair-wise comparison. After that the weighted linear combination (WLC) method was used to obtain the suitability index map for candidate landfill sites. Ten suitable candidate sites for landfill were selected (two for each District), where all these sites satisfied the scientific and environmental criteria which were adopted in this study. The areas of the selected sites were adequate to accommodate solid waste from 2020 until 2030.

  • 321.
    Chabuk, Ali Jalil
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Analysis of Landfill Site Selection-Case Studies Al-Hillah and Al-Qasim Qadhaas, Babylon, Iraq2016Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The selection of a landfill site is considered as a complicated task because the whole process is based on many factors and restrictions. This study shows the present status of solid waste management, solid waste sources, staffing for solid waste collection, machinery and equipment used in the waste collection process, finance and financial management at Babylon Governorate and its Qadhaa. The management of collection and disposal of waste in Babylon Governorate and its Qadhaa is done through open dumping of waste and the quality of the collection process is poor. This is the case in Al-Hillah Qadhaa, which is located in the central part of the governorate, Iraq and Al-Qasim Qadhaas, which is situated in the southern part of the Babylon Governorate, Iraq. These sites do not conform to the scientific and environmental criteria applied in the selection of landfill sites. 

    In the first part of the current study, to find out how much solid waste will be produced in the future; two methods were used to calculate the population growth in Al-Hillah and Al-Qasim Qadhaas to the year 2030. The results showed that the total waste in 2030 according to the first and second methods respectively will be 394,081 tonnes and 472,474 tonnes in Al-Hillah Qadhaa, and (54,481 tonnes and 76,374 tonnes) in Al-Qasim Qadhaa. The cumulated quantity of solid waste expected to be produced between 2020 and 2030 according to the first and second methods respectively was 3,757,387 tonnes and 4,300,864 tonnes in Al-Hillah Qadhaa, whilst in Al-Qasim Qadhaa it was 519,456 tonnes and 695,219 tonnes. The generation rate in 2020 will be (0.88 and 0.62) kg/ (capita. day) in Al-Hillah and Al-Qasim Qadhaas respectively; in year 2030, the generation rate will be (0.97 and 0.69) kg/ (capita. day) based on method 2 and an expected incremental increase in generation rate of 1 kg/ (capita. day) per year. 

    The second part of this study aims to find the best sites for landfills in Al-Hillah and Al-Qasim Qadhaas. For this reason, 15 criteria were adopted in this study (groundwater depth, rivers, soil types, agricultural land use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centres, villages and archaeological sites) using GIS (geographic information system), which has a large capacity for managing input data. In addition, the AHP (analytical hierarchy process) method was used to derive the relative weightings for each criterion using pairwise comparison. The suitability index map for candidate landfill sites was obtained. Two suitable candidate landfill sites were found to fulfill the scientific and environmental requirements in each Qadhaa, with areas of 9.153 km2 and 8.204 km2 respectively in Al-Hillah Qadhaa, and with areas of 2.766 km2 and 2.055 km2 respectively in Al-Qasim Qadhaa. The area of these sites can accommodate solid waste from 2020 until 2030 based on the required areas, which were 4.175 km2 and 4.778 km2 (Ali-Hillah Qadhaa) and 0.577 km2 and 0.772 km2 in (Al-Qasim Qadhaa) according to the first and second methods respectively.

  • 322.
    Charbit, Benjamin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Numerical analysis of laterally loaded lime/cement columns2010Inngår i: Proc. 20th European Young Geotechnical Engineers Conference, 2010Konferansepaper (Annet vitenskapelig)
  • 323. Chen, Y.
    et al.
    Hu, R.
    Zhou, C.
    Jing, Lanru
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    A permeability evolution model for crystalline rocks subjected to coupled thermo-hydro-mechanical loading2013Inngår i: Chinese Journal of Rock Mechanics and Engineering, ISSN 1000-6915, Vol. 32, nr 11, 2185-2195 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An anisotropic damage model was established for fluid-saturated crystalline rocks of low permeability in coupled thermo-hydro-mechanical (THM) loading conditions by using the micromechanical approach in the framework of thermodynamics. The proposed damage model accounts for the impacts of some important micromechanisms, such as the interstitial water pressure, normal stiffness recovery induced by compressed microcracks and sliding and shear dilatancy of closed microcracks, on the macromechanical properties of rocks under non-isothermal condition. On this basis, using various homogenization approaches, estimates were presented for the variations in effective permeability of cracked rocks induced by anisotropic damage propagation. The predictive limitations associated with the lower bound estimates for the effective permeability of damaged rocks were discussed; and a rigorous upper bound estimate was then presented to account for the influence of some important microstructural features, such as the connectivity and persistence of microcrack system, on the permeability variation. Existing laboratory tests on granite samples for damage-induced variation in permeability in triaxial condition and for uniaxial mechanical response after high-temperature thermal treatment, together with the in-situ measurements of excavation-induced damage zone and permeability variation in the surrounding rock of the TSX tunnel, were used to validate the proposed models.

  • 324. Chen, Y.
    et al.
    Zhou, C.
    Tong, Fuguo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Jing, Lanru
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Numerical model for fully coupled THM processes with multiphase flow and code validation2009Inngår i: Chinese Journal of Rock Mechanics and Engineering, ISSN 1000-6915, Vol. 28, nr 4, 649-665 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A numerical model for fully coupled THM processes with multiphase flow in porous media was developed based on the momentum, mass and energy conservation laws of the continuum mechanics and the averaging approach of the mixture theory over a solid-liquid-gas three-phase system. To characterize multiphase THM coupling and to make the governing equations closed, complete and compatible, six processes and their coupling effects were considered, including stress-strain, water flow, gas flow, vapor flow, heat transport and porosity evolution processes. The physical phenomena such as phase transition, gas solubility in liquid, thermo-osmosis, moisture transfer and moisture swelling were modeled. As a result, the relative humidity of pore gas was defined on a sounder physical basis, avoiding the traditional definition as a negative exponential function of suction and absolute temperature. By selecting displacements, pore water pressure, pore gas pressure, pore vapor pressure, temperature and porosity as basic unknown variables, a finite element formulation was then established, and a three-dimensional computer code, THYME3D, was developed, with each node of 8 degrees of freedom. The bentonite THM Mock-up experiments performed by CEA were employed to validate the mathematical model and the software. The main coupling mechanisms involved in the experiments were satisfactorily simulated in the validation, and the effects of the governing equations, the constitutive relations and the parameters on the coupled THM processes were understood. The work developed enabled further in-depth research on fully coupled THM or THMC processes in porous media.

  • 325. Chen, Yifeng
    et al.
    Hu, Shaohua
    Zhou, Chuangbing
    Jing, Lanru
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Micromechanical Modeling of Anisotropic Damage-Induced Permeability Variation in Crystalline Rocks2014Inngår i: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 47, nr 5, 1775-1791 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a study on the initiation and progress of anisotropic damage and its impact on the permeability variation of crystalline rocks of low porosity. This work was based on an existing micromechanical model considering the frictional sliding and dilatancy behaviors of microcracks and the recovery of degraded stiffness when the microcracks are closed. By virtue of an analytical ellipsoidal inclusion solution, lower bound estimates were formulated through a rigorous homogenization procedure for the damage-induced effective permeability of the microcracks-matrix system, and their predictive limitations were discussed with superconducting penny-shaped microcracks, in which the greatest lower bounds were obtained for each homogenization scheme. On this basis, an empirical upper bound estimation model was suggested to account for the influences of anisotropic damage growth, connectivity, frictional sliding, dilatancy, and normal stiffness recovery of closed microcracks, as well as tensile stress-induced microcrack opening on the permeability variation, with a small number of material parameters. The developed model was calibrated and validated by a series of existing laboratory triaxial compression tests with permeability measurements on crystalline rocks, and applied for characterizing the excavation-induced damage zone and permeability variation in the surrounding granitic rock of the TSX tunnel at the Atomic Energy of Canada Limited's (AECL) Underground Research Laboratory (URL) in Canada, with an acceptable agreement between the predicted and measured data.

  • 326.
    Chikatamarla, R.
    et al.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Modelling of rockfall on protection galleries2006Inngår i: Physical Modelling in Geotechnics, 6th ICPMG'06: Proceedings of the 6th International Conference on Physical Modelling in Geotechnics, 2006, Vol. 1-2, 331-336 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rockfall impact energies can reach magnitudes of the order of millions of Joules, requiring understanding of the energy absorption mechanisms at high energy levels for improved design of the protection gallery. These high-energy ranges can be achieved at the laboratory scale with the help of a geotechnical centrifuge. In centrifuge, rockfall protection galleries are studied with an aim to optimise the design procedure by using a cushion material. Different cushion materials have been modelled against vertical and inclined impacts of steel block with input energy levels up to 20 MJ.A simple FE model (LS-DYNA) is used in addition to model the boulder impact on different cushion materials. The results from the centrifuge tests in terms of acceleration values of the boulder and deflection of the slab are discussed and a new design procedure for the protection galleries based on the centrifuge and numerical investigations has been proposed. © 2006 Taylor & Francis Group, London.

  • 327.
    Chikatamarla, R.
    et al.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Stress distribution of rockfall events on galleries2005Inngår i: Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering: Geotechnology in Harmony with the Global Environment, 2005, Vol. 4, 2789-2792 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rockfall galleries are built to protect local infrastructure and lifelines against rockfall events. They are covered usually with a soil layer, sometimes for aesthetical reasons but also for protection against impact from rockfalls and snow avalanches. The effect of the impact has been quantified in a research project by investigating the properties of the cover (cushion) material. The stress distribution caused by a rockfall event is measured in centrifuge model tests by means of a tactile multipoint pressure transducer on the gallery below the cushion material as well as point load measurements at supports and strain gauges to determine bending of the gallery slab. The technique of measuring stress distribution under a soil layer is adapted from bio-medicine and the car industry to soil mechanics. Features of these pressure sensors will be discussed in relation to the response to a rockfall event and for different types and thicknesses of cushion material. Numerical modelling has also been carried out using LS DYNA. Knowledge gained can be used for formulation of guidelines for the gallery design.

  • 328.
    Chikatamata, R.
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich, Institute for Geotechnical Engineering, ETH Zurich.
    Centrifuge scaling laws for guided free fall events including rockfalls2006Inngår i: International Journal of Physical Modelling in Geotechnics, ISSN 1346-213X, Vol. 6, nr 2, 15-26 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Concrete protection galleries are generally used in mountainous regions to protect the local infrastructure and lifelines against potential impacts from rock boulders. These can be protected further by carefully designed cushion systems, most of which rely on granular geomaterials. Rockfall impact energies can reach magnitudes of the order of millions of Joules, requiring understanding of the combined energy absorption mechanisms at high energy levels for improved design of the gallery and cushion. These prototype high-energy ranges can be achieved at the laboratory scale with the help of a geotechnical centrifuge. The model is rotated under high g levels, thereby increasing the unit weight of the material. Prototype energy levels can be represented in a small scale model with consideration of appropriate scaling laws, and although free fall events in a centrifuge experience components of the Coriolis acceleration, projectiles (boulders) will move out of the centripetal gravity field when losing contact with the rotational field. A guiding tube is used in this case to keep the boulder in the acceleration field (ng) in order to achieve sufficient input energy levels to represent existing design criteria. The change in the g-level during the fall of the boulder in the centrifuge, due to the change in the radius, has to be taken into account for determination of the impact energy. In this case, direct application of traditional scaling laws for centrifuge modelling is invalid. This paper focuses on the determination of the change in the g field with time during the fall of the boulder to estimate the g level at the time of impact and this value is used in the calculation of the prototype energy levels. A summary of the performance of various cushion materials is given

  • 329.
    Clark, Anna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Clarin, Viktoria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    The Incidence and Associated Geotechnical Issues of Swelling Clay in Stockholm2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The Incidence and Associated Geotechnical Issues of Swelling Clay in Stockholm 

    Viktoria Clarin & Anna Clark 

    Previous tunnel failures have shown that inadequate reinforcement in tunnels can lead to cave-ins, whereby swelling clay is one of several factors that can result in these damages. Swelling clay minerals possess the ability to absorb water molecules and cations leading to an increase in volume. Instability in tunnels is a consequence of the mobilised swelling pressure caused by lack of room to accommodate for the change in volume. Several tunnels are projected throughout central Stockholm in the near future, whereby numerous drill cores have been logged. This bachelor thesis will therefore focus on the swelling potential and swelling pressure of clay samples selected from a drill core traversing the Söderström fault system. The samples selected for further analysis were collected from a drill core from Slussen, Stockholm, with the aim of determining the reinforcement requirements for future tunnelling projects. 

    Several samples from the drill core were selected for analysis, whereby free swelling test was conducted to determine the swelling potential for each sample. One sample displayed more than 100% volume increase and was further tested to determine swelling pressure. Tests were performed using an oedometer, resulting in a measured swelling pressure of approximately 155kPa. To identify the clay type several X-ray diffraction tests were performed on the sample. 

    Similar swelling pressures have been measured in tunnels affected by cave-ins in Norway. Due to these previous events, the swelling pressure is of imminent importance when constructing new tunnels. Based on the obtained results, an adequate reinforcement can be estimated and used as a foundation for future tunnel constructions within the area. The tests show that the Söderström fault contains swelling clay and precautions will have to be taken when tunnels are constructed.

  • 330.
    Cleveson, Aron
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska högskolan.
    Sheet piling for permanent application in solid water hazards for construction of fishways.2014Independent thesis Basic level (university diploma), 20 poäng / 30 hpOppgave
    Abstract [en]

    När ett vattendrag regleras genom byggnation av dammar och vattenkraftverk skapas hinder, även så kallade vandringshinder för fiskar och andra vattenlevande organismer. Genom att bygga en fiskväg möjliggörs åter denna vandring. På senare år har det blivit vanligt att anlägga fiskvägar på ett naturligt sätt. Den senast framtagna metoden för att anlägga naturliga fiskvägar är att bygga ett så kallat inlöp. Inlöpet uppförs genom att en del av en damm skiljs av med hjälp av en skiljevägg som ansluts mot befintlig dammkonstruktion. Skiljeväggen kan utföras på flera sätt, ett av dess är genom att driva ner en kontinuerlig stålspont. Syftet med examensarbetet är att undersöka möjligheten att uppföra ett inlöp med hjälp av en tät kontinuerlig konsolspont av stål, i anslutning till befintlig dammkonstruktion. Målet med examensarbetet är att öka kunskapen vid användning av kontinuerlig stålspont för byggnation av fiskvägar i anslutning till befintliga dammkonstruktioner.

  • 331. Costa, Pedro Alves
    et al.
    Calçada, Rui
    Cardoso, António Silva
    Bodare, Anders
    Geo Risk and Vibration Scandinavia AB.
    Influence of soil non-linearity on the dynamic response of high-speed railway tracks2010Inngår i: Soil Dynamics and Earthquake Engineering, ISSN 0267-7261, E-ISSN 1879-341X, Vol. 30, nr 4, 221-235 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The main objectives of this paper are the evaluation of the relevance of the non-linear behaviour of the soil on the track response and the validation of a methodology, which includes these effects through an equivalent linear analysis. The proposed numerical model is based on 2.5D finite/infinite elements method, coupled with an iterative procedure in order to obtain an agreement between the strain levels and the dynamicproperties of the materials. In order to validate the model, the case study of Ledsgard was simulated, and the experimental and numerical results of displacements of the trackwere compared, considering several circulation speeds for the X2000 train. From the results, it is possible to recognize that the stiffness degradation, function of the strain level, plays a relevant role for the case of high-speed railway lines on soft ground. Moreover, the simulations developed with the proposed methodology provided similar results to those observed, independently of the train speed, contrary to what was obtained when the elastic linear model was used.

  • 332.
    Cvetkovic, Vladimir
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Soltani, Safeyeh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Vigouroux, Guillaume
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Global sensitivity analysis of groundwater transport2015Inngår i: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 531Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work we address the model and parametric sensitivity of groundwater transport using the Lagrangian-Stochastic Advection-Reaction (LaSAR) methodology. The 'attenuation index' is used as a relevant and convenient measure of the coupled transport mechanisms. The coefficients of variation (CV) for seven uncertain parameters are assumed to be between 0.25 and 3.5, the highest value being for the lower bound of the mass transfer coefficient k0. In almost all cases, the uncertainties in the macro-dispersion (CV = 0.35) and in the mass transfer rate k0 (CV = 3.5) are most significant. The global sensitivity analysis using Sobol and derivative-based indices yield consistent rankings on the significance of different models and/or parameter ranges. The results presented here are generic however the proposed methodology can be easily adapted to specific conditions where uncertainty ranges in models and/or parameters can be estimated from field and/or laboratory measurements.

  • 333.
    Dagli, Deniz
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laboratory Investigations of Frost Action Mechanisms in Soils2017Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Phase change of the water in the soil skeleton under cold climate conditions (also known as frost action in soils) affects soil properties and can be responsible for serious alterations in a soil body; causing damages (due to the volumetric expansion known as frost heave) to structures on or below the ground surface such as foundations, roads, railways, retaining walls and pipelines, etc. In order to improve the current design methods for roads against frost action, the Swedish Transport Administration (Trafikverket) has initiated a research program. The main goals of the program are to revise the existing frost heave estimation methods and improve the frost susceptibility classification system for subgrade soils.

    Literature was reviewed to gather the details of different freezing test equipment around the world and to identify common trends and practices for laboratory freezing tests. Based on the literature review and the collaboration with the University of Oulu, Finland an experimental apparatus was assembled for studying frost action in the laboratory. A detailed description of the experimental apparatus is given. Top to down freezing of specimens (of 10cm height and diameter) can be monitored while keeping track of water intake, vertical displacements (heave) and the temperature profile within the sample. Loads can be applied at the top of the sample to study the effects of overburden. Moreover, the test setup was modified with a camera system to have the option of recording the experiments.

    Disturbed samples of two different soil types were tested. Experiments with fixed and varying temperature boundary conditions were conducted to assess the validity of the assumptions for the frost heave estimation methods currently in use in Sweden. To this end, a qualitative relationship between frost heave and heat extraction rates based on theoretical equations was established. It was shown that there is a significant difference between the preliminary findings of the experimental work and the current system being used in Sweden to quantify heave.

    Image analysis techniques were used on two experiments that were recorded by the camera system. Image recording and correlation analyses provided detailed information about frost front penetration and ice lens formation(s) under varying temperature boundary conditions. Thawing has also been regarded in further studies. Results of the image analyses were compared to readings from conventional displacement measurements during the same test. Significant agreement between the results of image analyses and displacement measurements has been found. Image analysis was shown to be a viable method in further understanding of frost heave mechanisms.

    Shortcomings and disadvantages of utilizing the theoretical equations as well as the image analysis techniques were discussed. Potential remedies for overcoming the drawbacks associated with each approach are suggested. The work is concluded by discussing the potential improvements, planned upgrades (addition of pore pressure transducers) and the future experiments to be conducted.

  • 334.
    Dagli, Deniz
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zeinali, Amin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Gren, Per
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Image analyses of frost heave mechanisms based on freezing tests with free access to water2018Inngår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 146, 187-198 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A freezing test apparatus was supplemented with a camera to allow for recording and monitoring one-dimensional freezing tests to analyze the development of ice lenses via particle image velocimetry (PIV) in the laboratory. Two tests on disturbed, partially saturated samples of silt loam were conducted. Image recording and correlation analyses provided detailed information about frost front penetration and ice lens formation(s) under varying temperature boundary conditions. Thawing has also been regarded in further studies.

    Results of the image analyses were compared to readings from conventional displacement measurements during the same test. Significant agreement between the results of image analyses and displacement measurements has been found. Test results were also used to establish a qualitative relationship between heat extraction and heave rates. Advantages and disadvantages of utilizing image analysis methods were discussed. Potential remedies for overcoming the drawbacks of using image analysis are suggested.

    Image analysis is shown to be a viable method in further understanding of frost heave mechanisms.

  • 335.
    Dagli, Deniz
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zeinali, Amin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Edeskär, Tommy
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Theoretical Analysis of the Relationship between Heave and Net Heat Extraction Rates Based on Freezing Experiments2016Inngår i: Proceedings of Nordic Conference on Soil Mechanics and Geotechnical NGM: Reykjavik, Iceland 25th – 28th of May 2016, 2016, 411-421 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to improve the current design of roads against frost action, the Swedish Transport Administration (Trafikverket) has initiated a research programme. The main goals of the research are to revise the existing frost design models and the frost susceptibility classification system for subgrade soils.A qualitative theoretical analysis to establish a relationship between frost heave and net heat extraction rates based on experimental data has been done. Experiments were carried on disturbed (hand compacted), saturated samples of same type of soil without any overburden. Several different cold end temperatures were applied to create different boundary conditions to make a more detailed analysis.Results were analysed and compared to those of other researchers while pointing out the similarities and differences. Potential reasons for these differences have been identified. Based on the findings of the experimental work, suggestions for improvements are given for future testing. Some preliminary results providing hints for the relationship between segregational heave and net heat extraction rates were obtained. At the end it was shown that there exists a significant difference between the findings of the experimental work and the current system being used in Sweden in order to quantify heave.

  • 336.
    Dahlberg, Stina
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Bärförmågetillväxt i pålad friktionsjord2012Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Piled friction soil show a set-up which is increasing with the time after installation. The cost could be reduced if the set-up had been taken into account when designing but in Sweden it is very unusual to do that. Previous studies showed that set-up can vary between 25 % and 75 % during the first 90 days after pile installation. This showed that the effect of the phenomenon is difficult to predict. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in friction soils located in Sweden. The expectations from this study were whishes that the large dispersion should be reduced. This was not the case. One example of the wide dispersion is two piles which are 29 meters long and installed in Södertälje. One of the piles had a set-up of 249 % for 21 days while the other one had a loss of 7 % in bearing capacity during the same time interval. Since these large dispersions encountered it was found that soil characteristics and composition has a major impact on the coming set-up. Friction soil exhibit variations in properties such as how dense it is, the variety and size of layers in the soil profile and grain size. These are all not possible to determine if it not is a research project or some kind of project where detailed surveys are can be done considering time and money. Another parameter that indicated to have impact on the outcome of the phenomenon was the order of installations of the piles. Stress rearrangement in the soil is one of the mechanisms behind the set-up. An empirical relationship to predict the bearing capacity has been used as the piles have been compared with each other. An interesting finding of the study showed that the pile length influences how large the pile set-up gets.

    One design method for piles that takes into account the pile set-up is the ICP-method but is barely used in Sweden. To see how well and if this method match the results from dynamic pile tests calculations has been done. Average showed that the ICP-method gave a 13 % lower bearing capacity than the real value. There are several reasons that this method differs from the values from test data. For example the CPT tests were not as deep as the piles so the stress from the pile toe is just extrapolated. The friction angle in the soil is based on empirical data which means that the friction angle between concrete and soil is empirical as well which affect the result significantly.

  • 337.
    Dahlberg, Stina
    Ramböll.
    Pile set-up in cohesionless soil2013Inngår i: Proceedings of the 5th International Young Geotechnical Engineers Conference: 5th iYGEC 2013, Amsterdam: IOS Press, 2013, 403-406 s.Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Piled cohesionless soil shows an increase of bearing capacity with time after installation, this phenomenon is called set-up or freeze. The cost could be reduced if the set-up had been taken into account when designing pile foundation, but in Sweden it is very unusual to do that. Previous studies showed difficulty to predict the phenomenon and that set-up can vary between 25% and 75% during the first 90 days after the pile installation. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in cohesionless soils located in Sweden. An empirical relationship to predict the bearing capacity has been used in the study. An interesting result of the study showed that the pile length influences how large the pile set-up gets. A parameter that indicated to have impact on the outcome of the phenomenon was the order of installations of the piles. Stress rearrangement in the soil is one of the mechanisms behind the set-up.

  • 338.
    Daniels, Markus
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Katarina, Lovén
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Differences in ground vibrations generated from installation of bored and vibrated retaining walls - A field study2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 339.
    Daniels, Markus
    et al.
    Bjerking AB.
    Lovén, Katarina
    Skanska Sverige AB.
    Larsson, Stefan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Berg, Joakim
    Skanska Sverige AB.
    Studie visar fördelarna med borrad spont med avseende på markvibrationer2015Inngår i: Bygg & teknik, ISSN 0281-658X, nr 1, 36-39 s.Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Då det byggs allt tätare och i känsliga områden blir det allt vanligare att man måste ta hänsyn till markvibrationer. Anläggningsarbeten såsom packning, borrning och pål- och spontinstallationer genererar markvibrationer som kan skada intilliggande bebyggelse, påverka marken negativt samt skapa en otrivsam vistelsemiljö. I känsliga områden är det viktigt att kunna välja rätt metod som skapar acceptabla vibrationsnivåer.

      Det är allmänt vedertaget att vibrationerna som skapas vid installation av borrade stålrör är mindre än vibrationer genererade vid installation av vibrerad spont och slagna pålar. Det har dock inte gått att finna några tillgängliga studier där markvibrationer genererad från borrning respektive vibrerad spont har uppmätts parallellt. Fördelen av att använda borrade stålrör har därför inte kunnat påvisas. Att förutspå vibrationerna analytiskt är mycket komplicerat då det finns ett stort antal parametrar som inverkar på resultatet, både vad det gäller installationsmetoden samt markens beskaffenhet. I Daniels & Lovéns (2014) examensarbete utfört för KTH och Skanska Grundläggning har för första gången en borrad RD-vägg och en vibrerad spont installerats inom samma område med lika markförhållanden samtidigt som vibrationerna uppmätts både i marken och på respektive sponttyp (Figur 1 och 2). Resultaten från undersökningen visar tydligt på skillnaderna i vibrationer och är tänkta att kunna användas vid projektering av spontarbeten där vibrationer blir en faktor att ta hänsyn till.

  • 340.
    Danielsson, Markus
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Borehole Dimension Impact on LHD Operation in Malmberget Mine2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Sublevel caving is a highly mechanizable mass mining method normally utilized in large, steeply dipping orebodies. The fragmented ore flows freely, aided by gravity, down to the drawpoint while the surrounding waste rock caves in due to induced stresses and gravity. Fragmentation of the blasted ore is a vital component in any mining operation and directly affects productivity and efficiency of the following production steps (Nielsen et. al, 1996).

    In an attempt to reduce mining induced seismicity in Malmberget, LKAB is initiating various trials. One of these trials involves a reduction in blasthole dimension and an increase in the number of blastholes utilized in each ring. A reduction in blasthole dimension is undertaken to achieve a less impactful mining operation in terms of disturbances to surface populated areas, particularly addressed to ground vibrations. Therefore, it is of utmost importance to analyse if fragmentation and production is affected as a consequence of this change.

    This thesis sets out to evaluate how fragmentation and the LHD operation is affected by variations in blasthole dimension. The evaluation is carried out through analysis of logged production data, on-site filming of the loading sequence and interviews with the LHD operators. The discoveries will be presented chronologically to illustrate the complexities related to compiling a viable dataset to rely on for a credible analysis. The initial theory did not hold up properly and therefore the project was reshaped along the course of progression to provide further information and clarify uncertainties. Unfortunate, major production delays inhibited a quantitative comparison of two parallel drifts with different blasthole dimensions. Hence, no final answer can be provided in this thesis whether a change in blasthole dimension causes any differences in loadability and/or fragmentation or not. However, an analysis of how cycle times vary depending on causes such as operator induced differences, machine induced differences and road conditions will be provided. The field test also provides information on various loading scenarios and the difficulties connected to these.

    The result obtained in this project mainly addresses the significant operator difference in terms of cycle times which can extend to, on average, 60% depending on experience, road conditions and, most likely, preferences amongst operators. Time differences amongst seemingly experienced operators can reach more than, on average, 30% in hauling time alone. Roughly 96% of the operators state that road conditions in the production area is the controlling factor for hauling speed. Many of the operators further states that the risk of injuries is directly related to road conditions and this is a likely cause to why cycle times vary in this magnitude. Fragmentation was found to affect loadability but not to the same extent as shape and looseness of the muck pile. Compaction of the muck pile and flow disturbances where normally found to be connected to one another. Hence, good loadability would indicate a low occurrence of flow disturbances and a continuous flow of material into the drawpoint.

    This thesis is written as a part of the final stage of the civil engineering program at Luleå University of Technology (LTU) and represents 30 credits in the field of Soil and Rock Construction. The thesis is a part of a larger project, Face to surface, which sets out to analyse the impact of fragmentation on different stages in the production chain.

  • 341.
    Darwesh, Ali K.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Maack Rasmussen, Thorkild
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kicks controlling techniques efficiency in term of time2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 5, 482-492 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Kicks are the result of under balance drilling operation. Time consumed to control the kicks will be different in depending on the controlling technique. Drilling fluid considered as a first barrier to control formation pressure and well kicks. Any advance in drilling fluids leads to more controlled operation in term of time. This paper will follow the general increasing profile of pressure before entering the reservoir. Both methods of well controlling technique; circulating techniques and non-circulating have been implemented in many oil blocks. The process of designing and casing selection, setting depth and many other issues is predominately dependent on the utilization of accurate values of formation pressure. Formation pressures used to design safe mud weights to overcome fracturing the formation and prevent well kicks. Hence the emphasis has been placed on the practical utilization of kicks pressure near the reservoir. The presented relationships will help the engineer to better understand lithological columns and reduce potential hole problems during the kick appearance. Selecting the best well controlling practical method can lead to not harming the reservoir and more production later. Changes in some drilling fluid properties have been proposed with increasing the depth without damaging the reservoir. Suggestions in relation to the casing setting point of the intermediate section are also proposed. Standard equations with proper modification for gases and safety margin have been proposed for the future drilling operation in oil fields above the reservoir.

  • 342.
    Darwesh, Ali K.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Time Optimizing near the Pay Zone2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 10, 848-858 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Well control techniques are used in oil and gas drilling operations to control bottom hole pressure and avoid any fluid influx from formation to the well. These techniques are highly important near the pay zone in term of time. Controlling formation fluid pressure and thereby the formations behavior in a predictable fashion will help toward more optimized environmental friendly drilling operation. Time consumed to control the formation fluid pressure will range between few hours to many days. This paper discusses hydrostatic pressure distribution and changes near the pay zone for one oil blocks in Kur- distan, in the northern part of Iraq. Obtaining homogeneous increase in some drilling fluid properties will help the engineer to better interpret sampling of the lithological columns and reduce potential hole problems and operationtime.

  • 343.
    Darwesh, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of Limestone Interval in the Drilled Surface Section of Bn-1 Oil Well2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 8, 515-524 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The first exploration oil well in any oil block consumes in general more time and cost than the other wells in the same block. Evaluating the drilled wells serves to improve the future operations. This paper evaluates the drilled surface section through real field data for the first exploration oil well drilled in one of the oil blocks, in Kurdistan north of Iraq. The surface section of the well was drilled with the conventional method to penetrate many different geological formations with tight intervals. Drilling efficiency and the difficulties encountered are discussed and explained using various data sources. All daily drilling reports concerning a specific interval were studied. This includes weight on bit, string rotation, mud pump flow and penetration rate. Evaluation was carried out by analyzing the used controllable drilling parameters with the formations features. Penetration of the Pila Spi formation (Middle Eocene) was the most difficult formation in the drilled section. Microsoft Office 365 Pro Plus used in making graphs and Excel tables. Evaluations showed that the conventional technology used left many negative effects, like increase in None Productive Time NPT, cost and ground water pollution. Simultaneous Casing Drilling method proposed as an alternative method for the future campaign.

  • 344.
    de Frias Lopez, Ricardo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Granular Materials for Transport Infrastructures: Mechanical performance of coarse–fine mixtures for unbound layers through DEM analysis2016Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Granular materials are widely used as unbound layers within the infrastructure system playing a significant role on performance and maintenance. However, fields like pavement and railway engineering still heavily rely on empirically-based models owing to the complex behaviour of these materials, which partly stems from their discrete nature. In this sense, the discrete element method (DEM) presents a numerical alternative to study the behaviour of discrete systems with explicit consideration of the processes at particulate level governing the macroscopic response.

     This thesis aims at providing micromechanical insight into the effect of different particle sizes on the load-bearing structure of granular materials and its influence on the resilient modulus and permanent deformation response, both of which are greatly influenced by the stress level. In order to accomplish this, binary mixtures of elastic spheres under axisymmetric stress are studied using DEM as the simplest expression for gap-graded materials, which in turn also can be seen as a simplification of more complex mixtures.

    First, the effect of the fines content on the force transmission at contact level was studied. Results were used to define a soil fabric classification system where the roles of the coarse and fine fractions were defined and quantified in terms of force transmission.

    A behavioural correspondence between numerical mixtures and granular materials was established, where the mixtures were able to reproduce some of the most significant features regarding the resilient modulus and permanent strain dependency on stress level for granular materials.

    A good correlation between soil fabric and performance was also found. Generally, higher resilient modulus and lower deformation values were observed for interactive fabrics, whereas the opposite held for instable fabrics.

    Mixtures of elastic spheres are far from granular materials, where numerous additional factors should be considered. Nevertheless, it is the author’s belief that this work provides insight into the soil fabric structure and its effect on the macroscopic response of granular materials.

  • 345.
    de Frias Lopez, Ricardo
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Ekblad, Jonas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Vägtekniks laboratorium.
    Silfwerbrand, Johan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    A Numerical Study on the Permanent Deformation of Gap-Graded Granular Mixtures2016Inngår i: Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance / [ed] J. Pombo, Stirlingshire, UK: Civil-Comp Press , 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Permanent deformation accumulation of unbound granular layers under traffic plays a critical role in the performance and need for maintenance of pavements and railway structures. In this paper, the discrete element method is used to study the permanent strain behaviour of binary mixtures of elastic spheres, as an idealization of gap-graded mixtures, under triaxial monotonic loading. The effects of stress level and soil fabric structure, based on a recently proposed classification system founded on micromechanical considerations, are assessed by subjecting mixtures with varying fines contents to different stress levels. Additionally, mixtures are loaded to static failure to study the dependency of the permanent strains on the closeness of the applied stress to failure stress, in accordance with existing empirical models. Numerical results are also compared with the experimentally determined behaviour of granular materials. The findings indicate that numerical mixtures are able to reproduce some of the most significant features observed in laboratory tests on granular materials, further encouraging the use of numerical simulations to enhance the understanding of granular media behaviour. Additionally, a good correlation between fabric structure and performance is obtained, giving additional support to the use of the studied fabric classification system for performance characterization.

  • 346.
    de Frias Lopez, Ricardo
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Ekblad, Jonas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Vägtekniks laboratorium.
    Silfwerbrand, Johan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    Resilient properties of binary granular mixtures: A numerical investigatio2016Inngår i: Computers and geotechnics, ISSN 0266-352X, E-ISSN 1873-7633, Vol. 76, 222-233 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of stress level on the resilient modulus for binary mixtures of elastic spheres under triaxial loading is investigated using the discrete element method. The secant modulus during the first cycle of unloading is used as an estimate of the modulus after several load cycles due to computational time restrains. Later in the paper, its adequacy as an accurate and efficient estimator is shown. Numerical results are statistically compared with existing relations characterizing the stress dependency of the resilient modulus for real granular materials. It is concluded that the modulus prediction is significantly improved considering the effect of the deviator stress in addition to the confinement stress, obtaining a good correlation between the modulus and the confinement to deviator stress ratio for the numerical mixtures. The stress dependency of a recently proposed soil fabric classification system, based on force transmission considerations at particulate level, is also studied and its correlation with performance investigated. It is found that the relative load-bearing role of coarse and fine components is governed by the deviator to confinement stress ratio. However, the implemented fabric classification is fairly insensitive to changes in this ratio. Regarding resilient performance, interactive fabrics show the stiffest response whereas underfilled fabrics should be avoided due to a potential for instability.

  • 347.
    de Frias Lopez, Ricardo
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Silfwerbrand, Johan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    Jelagin, Denis
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggnadsmaterial.
    Birgisson, Björn
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Vägtekniks laboratorium. School of Engineering and Applied Science, Aston University, Birmingham, UK.
    Force transmission and soil fabric of binary granular mixtures2016Inngår i: Geotechnique, ISSN 0016-8505, E-ISSN 1751-7656, Vol. 66, nr 7, 578-583 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of fines content on force transmission and fabric development of gap-graded mixtures under triaxial compression has been studied using the discrete-element method. Results were used to define load-bearing soil fabrics where the relative contributions of coarse and fine components are explicitly quantified in terms of force transmission. Comparison with previous findings suggests that lower particle size ratios result in higher interaction between components. A potential for instability was detected for underfilled fabrics in agreement with recent findings. It was also found that the threshold fines content provides an accurate macroscopic estimation of the transition between underfilled and overfilled fabrics.

  • 348. Deckner, F.
    et al.
    Gabrielsson, J.
    Andersson, M.
    Lindgren, Mattias
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Norström, L.
    Unverzagt, A.
    Larsson, N.
    Müller, R.
    Bergman, Niclas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Jordförstärkning2010Rapport (Annet vitenskapelig)
  • 349.
    Deckner, Fanny
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Ground vibrations due to pile and sheet pile driving: influencing factors, predictions and measurements2013Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Ground vibrations due to pile driving are part of a complex process. Vibration is generated from the pile driver to the pile. As the pile interacts with the surrounding soil, vibrations are transferred at the pile-soil interface. The vibration propagates through the ground and interacts with structures, both above ground and underground. The vibration continues into the structure where it may disturb occupants and/or damage the structure.

    In this thesis the study of the vibration transfer process due to pile driving is limited to the vibration source and the wave propagation in the soil. Vibration transmission to adjacent buildings and structures is not studied. However, impact of vibrations on buildings is briefly discussed in the literature study.

    It is important to accurately predict the magnitude of ground vibrations that result from pile driving in urban areas, both over- and underestimated vibration levels lead to increased costs. A lot of research has been performed within this field of knowledge, but a reliable and acknowledged prediction model for vibrations induced by pile or sheet pile driving is still needed.

    The objective of the research project is to increase the knowledge and understanding in the field of ground vibrations due to impact and vibratory driving of piles and sheet piles. This research project also aims to develop a reliable prediction model that can be used by practising engineers to estimate vibration due to pile driving. This licentiate thesis presents the first part of the research project and aims to increase the knowledge and understanding of the subject and to form a basis for continued research work.

    The most important findings and conclusions from this study are:

    • The main factors influencing vibrations due to pile and sheet pile driving are; (1) the vibrations transferred from the pile to the soil, (2) the geotechnical conditions at the site and (3) the distance from the source.
    • The vibrations transmitted from the pile to the soil depend on the vibrations transferred to the pile from the hammer, the pile-soil interaction and the wave propagation and attenuation in the plastic/elasto-plastic zone closest to the pile.
    • There is today no prediction model that fulfils the criteria of the “perfect” prediction model; reliable but yet easy to apply.

    Future research should study the transfer of vibrations at the pile-soil interface, including the generation of a plastic/elasto-plastic zone in the area closest to the pile and how that affects the transfer of vibrations from the pile to the soil.

  • 350.
    Deckner, Fanny
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Vibration transfer process during vibratory sheet pile driving: from source to soil2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Vibratory driven sheet piles are a cost-effective retaining wall structure, and in coming decades the continued use of this method will be crucial for minimising costs within the construction sector. However, vibratory driven sheet piles are a source of ground vibrations, which may harm structures or induce disturbance. Most urban construction projects face strict limits on permissible vibration level. Being able to reliably predict the expected vibration level prior to construction is therefore highly important. Reliable prediction demands a profound knowledge of the vibration transfer process, from source to point of interest. This thesis focuses on clarifying the vibration transfer process and will serve as a platform for the future development of a reliable prediction model. The vibration transfer process is divided into two main parts: vibration source and vibrations in soil. The different parts in the vibration transfer process are studied and investigated with the help of a literature review, field tests and numerical modelling. Within the scope of this thesis, three field tests have been conducted and a new instrumentation system has been developed. The new instrumentation system enables recording of both sheet pile vibrations and ground vibrations at depth during the entire driving. The field tests aimed to study the vibration transfer from sheet pile to soil and the vibration transfer within a sheet pile wall, as well as the wave pattern in soil. To study sheet pile behaviour during driving a numerical model was developed, which is also meant to serve as a basis for further studies. The main scientific contribution of this thesis is the identification of the sheet pile behaviour during driving. For practical application, the main contribution is the development of an increased knowledge of the vibration transfer process from source to soil, together with the new instrumentation system and the development of the numerical model.

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