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  • 51.
    Buchheister, J.
    et al.
    ETH Zurich.
    Bayraktarli, Y.
    Laue, Jan
    ETH Zurich.
    Faber, M.
    Uncertainities in a detrministic and probabilistic approach on liquefaction susceptibility2006Konferansepaper (Fagfellevurdert)
  • 52.
    Buchheister, J.
    et al.
    ETH Zurich.
    Laue, Jan
    ETH Zurich.
    Frist results of cyclic experiments using a hollow cylinder apparaturs2006Konferansepaper (Fagfellevurdert)
  • 53.
    Buchheister, Justine
    et al.
    Institute for Geotechnical Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich.
    The influence of different stress states on soil liquefaction under a building2007Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Liquefaction of soil depends on the state and type of soil, loading function and the initial stress state ofa soil element prior to a dynamic event. Most studies focus on an initial stress state from the free fieldwhile assuming σ2 = σ3. Therefore, this stress state can be studied in a triaxial apparatus. With ahollow cylinder apparatus, it is possible to apply any possible combination of σ1, σ2 and σ3 in the soilprior to testing and thus enables the reproduction of boundary conditions e.g. as given for different soilelements under a building.Underneath a building different initial stress states need to be taken into account to judge the safetyand the behavior of the building during and after an earthquake. The focus in this contribution is tostudy the influence of these stress states. For a typical building the initial stress states were chosen atthree locations in a depth of 5 m. Experiments with fine sand are carried out under these initial stressstates with combined cyclic shear and axial loading. The results are presented and discussed in termsof the influence of stress state on liquefaction susceptibility and potential failures modes of a buildingtype to be considered in soil structure interaction.

  • 54.
    Buchli, Thomas
    et al.
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich.
    Laue, Jan
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich.
    Springman, Sarah M
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich.
    Amendments to Interpretations of SAAF Inclinometer Data from the Furggwanghorn Rock Glacier, Turtmann Valley, Switzerland: Results from 2010 to 20122016Inngår i: Vadose Zone Journal, ISSN 1539-1663, E-ISSN 1539-1663, Vol. 15, nr 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Raw data processing from a ShapeAccelArray field (SAAF) inclinometerwere made using proprietary software from Measurand, the manufacturerof the SAAF inclinometer. When the inclinometer data obtained from thesame borehole were reprocessed with an updated software version, theresults were found to differ significantly from the values derived using theprevious version of software. Neither the absolute displacements nor thecurve representing displacements with depth agreed with the previous values,despite our best attempts to compare data with alternative sparse fieldmeasurements of surface displacements. There was a change in inclinationof the segments above the shear zone, and the strain rates in the shear zonewere reduced significantly during the winter months. In contrast, there wasno change in the depth of the shear zone. Therefore, the ground modelpresented in the original study is still considered to be the optimal groundmodel of the Furggwanghorn rock glacier. Finally, a simple trigonometricalapproach was conducted to investigate the validity of both software versions.The simplified recalculations could confirm mostly the results of theupdated software version.

  • 55.
    Burjánek, J.
    et al.
    Swiss Seismological Service, ETH Zürich.
    Fäh, D.
    Swiss Seismological Service, ETH Zürich.
    Michel, C.
    Swiss Seismological Service, ETH Zürich.
    Dalgauer, L.
    Swiss Seismological Service, ETH Zürich.
    Baumann, C.
    Swiss Seismological Service, ETH Zürich.
    Gassner-Stamm, G.
    Swiss Seismological Service, ETH Zürich.
    Poggi, V.
    Swiss Seismological Service, ETH Zürich.
    Roten, D.
    Swiss Seismological Service, ETH Zürich.
    Laue, Jan
    Institute of Geotechnical Engineering, ETH Zürich.
    Marin, A.
    Institute of Geotechnical Engineering, ETH Zürich.
    Lestuzzi, P.
    Applied computing and Mechanics Laboratory, EPF Lausanne.
    Karbassi, A.
    Applied computing and Mechanics Laboratory, EPF Lausanne.
    Earthquake Damage Scenario in Visp (Switzerland): From Active Fault to Building Damage2012Inngår i: Proceedings of the 15th World Conference on Earthquake Engineering 2012 (15WCEE), ETH Zürich , 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We present a damage scenario based on multidisciplinary study which covers the key elements of the earthquakerisk chain in Visp. Full dynamic rupture simulations are performed using heterogeneous initial distributions,statistically compatible to the database of kinematic inversion results of past earthquakes. The fault is embeddedin the 3D velocity model of the area, which is based on an extensive ambient noise measurement campaign. Inorder to assess the risk in the city of Visp, the buildings were classified based on the screening survey of thebuilding stock. The seismic behavior of each class is described by the mean of fragility curves, partly developedby analytical, numerical and experimental investigations and partly based on existing methods

  • 56.
    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.

  • 57.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Alkaradaghi, Karwan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Kurdistan Institution for strategic studies and scientific Research, Sulaimaniyah, Iraq.
    Al-Rawabdeh, Abdulla Mustafa Muhamed
    Abdullah Mustafa Muhamed Al-Rawabdeh, Department of Earth and Environmental Science, Yarmouk University, Irbid, Jordan.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa, Iraq; Department of Geology, Faculty of Science, University of Kufa, Kufa, Iraq.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Final Cover Systems Design for Arid Areas Using the HELP Model: A Case Study in the Babylon Governorate, Iraq2018Inngår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 12, artikkel-id 4568Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The main purpose of selecting proper designs for landfills is to accommodate quantities of waste without having a negative effect on the surrounding environment and human health. The Babylon Governorate (province) in Iraq was taken as an example of an arid area with very shallow groundwater and where irregular waste disposal sites had developed that had not been subject to international standards when they were selected for landfill use. In the current study, the suggested design for landfills is a base liner and final cover system. In this suggested design, the final cover system allows for three scenarios. The first scenario considers an evapotranspiration soil cover (ET) (capillary barriers type), the second scenario is a modified cover design of “RCRA Subtitle D”, and the third scenario is a combination of the first and second scenarios. The HELP 3.95 D model was applied to the selected landfill sites in the governorate to check if there was any penetration of the leachate that might in future percolate from the landfill’s bottom barrier layer in arid areas. The results from the suggested landfill design showed that there was no leachate percolation from the bottom barrier layer using the second and third scenarios. For the first scenario, however, there was a small amount of leachate through the bottom barrier layer in the years 2013 and 2014.

  • 58.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon 51001, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ezz-Aldeen, Mohammad
    Department of Dams and Water Resources Engineering, University of Mosul, Mosul 41001, Iraq.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa 51001, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Two Scenarios for Landfills Design in Special Conditions Using the HELP Model: A Case Study in Babylon Governorate, Iraq2018Inngår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 1, artikkel-id 125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The sound design of landfills is essential in order to protect human health and the environment (air, water, and soil). The study area, Babylon Governorate, is situated in the middle of Iraq, and is distinguished by a hot climate and shallow groundwater. The governorate did not have landfill sites that meet international criteria; in addition, the groundwater depth in Babylon Governorate is commonly shallow. Previously, the most important criteria for the study area and GIS software were used to select the best sites for locating landfills in the major cities of the governorate. In this study, the Hydrologic Evaluation of Landfill Performance (HELP 3.95D) model was applied in order to ensure that there was no leakage of the leachate that results from the waste in the selected landfill sites. It is the most commonly utilized model for landfill design, and it is used to estimate water inflow through the soil layers. For the present study, to avoid groundwater pollution by leachate from a landfill site due to the shallow groundwater depth, compacted waste was placed on the surface using two height scenarios (2 m and 4 m). This design was developed using the soil properties of the selected sites coupled with the weather parameters in Babylon Governorate (precipitation, temperature, solar, and evapotranspiration) for a 12-year period covering 2005 to 2016. The results from both of the suggested landfill designs showed an absence of leachate from the bottom liner.

  • 59.
    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, s. 348-363Artikkel 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.

  • 60.
    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, s. 723-737Artikkel 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.

  • 61.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, college of Engineering, U niversity of Babylon, Babylon, Iraq. .
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Remote Sensing Center, University of Kufa, Kufa, Iraq.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hazim, Anwer
    Koya university, Koya, Iraq.
    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 MCDM and Comparing Method of Change Detection for Babylon Governorate, Iraq2019Inngår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Landfill site`s selection represents a complicated process due to the large number of variables to be adopted. In this study, an arid area (Babylon Governorate as a case study) was selected. It is located in the middle region of Iraq. In this area, the  landfills do not satisfy the required  international criteria.  Fifteen  of the  most significant criterion were selected for this purpose. For suitable weight for each criterion, the multi criteria decision making (MCDM) methods were applied. These methods are AHP and RSW. In the GIS software 10.5, the raster maps of the chosen criterion were arranged and analysed. The method of change detection was implemented to determine the matching pixels and non-matching pixels. The final results showed that there are two candidate locations for landfills for each district in the governorate (ten sites). The areas of the selected sites were sufficient to contain the cumulative quantity of solid waste from 2020 until 2030.

  • 62.
    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, artikkel-id 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.

  • 63.
    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, s. 1-15Artikkel 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.

  • 64.
    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.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Alkaradaghi, Karwan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Kurdistan Institution for Strategic Studies and Scientific Research, Sulaimaniyah, Iraq.
    Hussain, Hussain M.
    Remote Sensing Center, University of Kufa, Department of Geology, Faculty of Science, University of Kufa, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of the HELP Model for Landfill Design in AridAreas: Case Study Babylon Governorate, Iraq2018Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 12, nr 12, s. 848-879Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The landfill design is necessary to be implemented in various regions to protect public human health and the factors ofenvironment. The suggested design of landfill was performed in the arid areas, where that Babylon Governorate, Iraq was selected as a case study. Babylon overnorate is located in the middle of Iraq. The suggested design for the selected sites for landfill in the arid areas was consisted of the base liner and final cover systems. The HELP 3.95D model was applied on both systems to check if there is any leakage by leachate from the suggested soil layers of landfill base on the water balance in Babylon Governorate for the years 2005-2016. The suggested design of final cover system was implemented based on weather parameters in the arid areas through storing water that coming from the surface within upper layers that have fine particles and over the top barrier without leakage into the waste body, thereby preventing leachate generation. This is  allowing to the stored water to evaporate from the surface of soil or transpire through vegetation due to the high temperature during the most months in the study area. The results showed there was no percolation of leachate through the base liner system. The design of final cover system was acted to reduce the runoff on the surface and increase theactual evaporation.

  • 65.
    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, s. 331-336Konferansepaper (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.

  • 66.
    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.
    Numerical modelling of rockfalls on protection galleries2005Inngår i: Prediction, analysis and design in geomechanical applications: the 11th international conference of IACMAG ; [Eleventh International Conference on Computer Methods and Advances in Geomechanics ; Torino, Italy, 19-24 June 2005] / [ed] Giovanni Barla, 2005, s. 489--497Konferansepaper (Fagfellevurdert)
  • 67.
    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.
    Rockfall impact on protection galleries2004Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rockfalls are one of the most prevailing natural hazards in the mountainous regions in Switzer- land. Concrete protection galleries are used to protect the local infrastructure and lifelines against these poten- tial rock impacts. Cushion materials are laid on these galleries to absorb the rockfall impact energy, which is one of the main input parameters in the design of the protection gallery. An attempt has been made to reduce the impact energies by placing a better damping material on the gallery. The high rock impact energy ranges are difficult to model at the laboratory scale. Field tests are generally avoided due to the high costs involved and also due to the singularity of the potential tests. The prototype energy levels can be achieved at the labo- ratory scale with the help of a geotechnical centrifuge. An instrumented model of the protection gallery is ro- tated under high g levels, thereby increasing the unit weight of the material. With the help of appropriate scal- ing laws, the prototype energy levels can be achieved. This paper focuses on the determination of the impact force of a rockfall of a specific energy and the forces induced in the gallery. The maximum acceleration val- ues of the rock and deflection of the galleries are compared for different energy ranges and cushion materials. The test results are later compared with numerical modelling using the finite element program LS-DYNA. Rockfall impact on protection galleries | Request PDF. Available from: https://www.researchgate.net/publication/242415233_Rockfall_impact_on_protection_galleries [accessed Aug 20 2018].

  • 68.
    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, s. 2789-2792Konferansepaper (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.

  • 69.
    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, s. 15-26Artikkel 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

  • 70.
    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, s. 187-198Artikkel 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.

  • 71.
    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, s. 411-421Konferansepaper (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.

  • 72. Dury, Robin
    et al.
    Bernander, Stig
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Kullingsjö, Anders
    Skanska Teknik AB.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Progressive Landslide Analysis with Bernander Finite Difference Method2017Inngår i: / [ed] Vikas Thakur, Jean-Sébastien L’Heureux, Ariane Locat, 2017, s. 1-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The poster presents a new Spreadsheet developed by Robin Dury (2017) to simplify the use of the Finite Difference Method developed by Stig Bernander et al (2011, 2016).

    It includes:

    - Material Properties

    - Finite Difference Method

    - Progressive failure process with five phses

    - Discussion

    - References

  • 73.
    Ekström, Ingvar
    et al.
    Sweco Energuide.
    Ljunggren, Magnus
    Sweco Energuide.
    Andersson, Carl Anders
    Sweco Energuide.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Large-scale shear box tests to determine rockfill parameters2016Inngår i: Association of State Dam Safety Officials Annual Conference 2016: Dam Safety 2016, Lexington, Kentucky: Association of State Dam Safety Officials , 2016, Vol. 2, s. 828-845Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A 160 (525 ft) m high asphalt concrete core rockfill dam is developed in an area of very high seismicity in Cetin, Turkey. Topographical constraints of the dam footprint impose a steep outer geometry of the dam, requiring the geotechnical properties of the rockfill to comply with certain minimum limits. Test blasting in a potential quarry and rockfill rolling compaction trials suggest that the tested gneiss/schist rock material to a large extent is weathered and weak. The friction angle of the rockfill is a decisive parameter for both the static and dynamic stability of the dam slopes and especially for the deformation of the dam crest due to strong earthquakes. The suggested rock fill material has therefore undergone detailed testing. To this end, large-scale shear tests with a 1000 mm diameter sample cylinder have been carried out at the Luleå Technical University in Sweden.

  • 74.
    Elfgren, Lennart
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Bernander, Stig
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Knutsson, Sven ()
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Response to and Comments on “Geotechnical Peer Review of Dr. S. Bernander’s Reports and Analysis of the North Spur”2018Rapport (Annet vitenskapelig)
    Abstract [en]

    The concerns regarding the stability of the North Spur can be summarized in three points:

    (1) None of the most critical inclined failure surfaces have been studied by Muskrat Falls Corporation. These failure surfaces may be initiated on the upstream side of the dam containment. Here the effects of the deformations, caused by the pressure of the rising water level, have to be resisted by the metastable soil layers in the North Spur. A local failure may occur progressing downwards towards the downstream side of the Spur. A catastrophic dam breach would follow. The GPRP further categorically overlooks the fact that horizontal failure planes cannot possibly represent the highest risk of instability irrespective of whether the analysis is based on the Limit Equilibrium Mode (LEM) or on the Progressive Failure Mode.

    (2) The stress/strain deformation properties of the porous soils in the North Spur have not been made available. Only strength properties, related to fully drained conditions, have been given. How stresses relate to simultaneous deformations under undrained (or partially undrained) conditions have not been defined in any way. Such relationships are crucially essential for any up-to-date analysis of slope stability.

    (3) A high risk of North Spur instability has been found related to impoundment.  A series of investigatory calculations have been made, based on deformation properties from similar landslides and on a wide variety of assumed input data for possible critical failure surfaces. The results of these analyses indicated a safety factor far below 1.

    The peer review does not address the above three points. It gives a good view of the general conditions but also contains misconceptions, erroneous considerations and refutable comments indicating that the earlier reports by Bernander have not been fully understood by the panel members.

    As no up-to-date analysis of the stability of the North Spur has been provided, our conclusion is that an independent group of experts, appointed by government, should be entrusted with this important task.

  • 75.
    Fäh, Donat
    et al.
    ETH Zurich, Institute of Geophysics.
    Moore, Jeffrey R.
    Department of Geology & Geophysics, University of Utah, Salt Lake City.
    Burjánek, Jan
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Iosifescu, I.
    Institute of Cartography and Geoinformation, Eidgenossische Technische Hochschule Zurich.
    Dalguer, Luis Angel
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Dupray, F.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Michel, Clotaire
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Woessner, Jochen K.
    Risk Management Solutions Inc.
    Villiger, A.
    Institute of Geodesy and Photogrammetry, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Marschall, Iris
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Gischig, Valentin Samuel
    Department of Earth, The University of British Columbia, Vancouver.
    Loew, Simon Imon
    Department of Earth Sciences, Eidgenossische Technische Hochschule Zurich.
    Marin, Alexandru
    Eidgenossische Technische Hochschule Zurich, POLITEHNICA University of Bucharest.
    Gassner, G.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Alvarez, S.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Balderer, Werner P.
    Department of Earth Sciences, Eidgenossische Technische Hochschule Zurich.
    Kästli, Philipp
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Giardini, D.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Iosifescu, C.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Hurni, Lorenz
    Institute of Cartography and Geoinformation, Eidgenossische Technische Hochschule Zurich.
    Lestuzzi, Pierino
    École Polytechnique Fédérale de Lausanne.
    Karbassi, A.
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Baumann, Cyrill
    Zurich Insurance Company Ltd, Group Reinsurance.
    Geiger, Alain
    Institute of Geodesy and Photogrammetry, Eidgenossische Technische Hochschule Zurich.
    Deichmann, Nicholas
    Swiss Seismological Service, Eidgenossische Technische Hochschule Zurich.
    Coupled seismogenic geohazards in Alpine regions2012Inngår i: Bollettino di Geofisica Teorica ed Applicata, ISSN 0006-6729, Vol. 53, nr 4, s. 485-508Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    COupled seismogenic GEohazards in Alpine Regions (COGEAR) is an interdisciplinary natural hazard project investigating the hazard chain induced by earthquakes. It addresses tectonic processes and the related variability of seismicity in space and time, earthquake forecasting and short-term precursors, and strong ground motion as a result of source and complex path effects. We study non-linear wave propagation phenomena, liquefaction and triggering of landslides in soil and rock, as well as earthquake-induced snow avalanches. The Valais, and in particular parts of the Rhone, Visper, and Matter valleys have been selected as study areas. Tasks include detailed field investigations, development and application of numerical modeling techniques, assessment of the susceptibility to seismically induced effects, and installation of different monitoring systems to test and validate our models. These systems are for long-term operation and include a continuous GPS and seismic networks, a test installation for observing earthquake precursors, and a system to study site-effects and non-linear phenomena in two test areas (Visp, St. Niklaus / Randa). Risk-related aspects relevant for buildings and lifelines are also considered

  • 76.
    Garmabaki, Amir Soleimani
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Thaduri, Adithya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Marklund, Stefan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Odelius, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Bansal, Tarun
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Indahl, Stefan
    A Survey on Underground Pipelines and Railway Infrastructure at Cross-Sections2019Inngår i: ESREL-2019 / [ed] Michael beer, Enrico Zio, 2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures are critical for society and industry resulting in direct and indirect costs for all the related stakeholders. Pipeline failures are complex processes, which are affected by many factors, both static (e.g., pipe material, size, age, and soil type) and dynamic (e.g., traffic load, pressure zone changes, and environmental impacts). These failures have serious impacts on public due to safety, disruption of traffic, inconvenience to society, environmental impacts and shortage of resources. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within transportation infrastructure. The aim of this study is to identify failure modes and consequences related to the crossing of pipelines in railway corridors. Expert opinion have been collected through two set of questionnaires which have been distributed to the 291 municipalities in the whole Sweden. The failure analysis revealed that pipe deformation has higher impact followed by pipe rupture at cross-section with railway infrastructure. For underground pipeline under railway infrastructure, aging and external load gets higher ranks among different potential failure causes to the pipeline.

  • 77.
    Gautray, J.
    et al.
    Institute for Geotechnical Engineering, ETH Zürich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, ETH Zürich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zürich.
    Investigation of the spatial distribution of installation effects around stone columns with an electrical needle2014Inngår i: Physical Modelling in Geotechnics - Proceedings of the 8th International Conference on Physical Modelling in Geotechnics 2014, ICPMG 2014, 2014, Vol. 1, s. 289-294Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Stone columns provide valuable ground improvement in soft soils in numerous projects around the world. They increase the stiffness of the subsoil and reduce time needed for consolidation. This last aspect is due to the fact that the main drainage direction switches from being vertical to being radial, significantly reducing the length of the drainage path. However, driving the installation mandrel into the ground causes changes in the structure of the subsoil, usually referred to as smear zones, which decrease the drainage performance of granular inclusions. The implementation of a needle to measure the impedance (electrical resistivity) in-flight in the geotechnical centrifuge at ETH Zürich enables an insight to be made into the pore size distribution with depth close to a stone column constructed in-flight. © 2010 Taylor & Francis Group, London.

  • 78.
    Gautray, J.
    et al.
    Institute for Geotechnical Engineering, ETH Zürich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zürich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Almeida, M.
    Federal University of Rio de Janeiro.
    Development of pore pressure around a stone column in soft soil2013Inngår i: / [ed] Delage et al, 2013, s. 915-918Konferansepaper (Fagfellevurdert)
  • 79.
    Gunnvard, Per
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of triangular pile arrangement through a numerical study of the light embankment piling method2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Embankment piling is a widely used foundation method in geotechnical engineering and the design is mostly based on empirical studies found on experimental or field evidents. Several studies have been conducted to capture the behaviour of embankment piles by means of numerical models. One of the issues is to simulate the arching effect between the piles. This has raised the question of the optimum pile arrangement. Along the northern coast of Sweden, where soft soil types and dense woodlands are common, timber piles have often been used in piled road and railway embankments. The pile group is designed as a semi-floating deep foundation in soft soil, where the piles are resting on top of the locally common firm glacial till bottom layer, naming the method light embankment piling. The Swedish design guidelines recently changed from a square to a triangular pile arrangement. However, the motivation of the changed lacked research which raised the question of optimal pile arrangement and centre-to-centre pile distance. This project aims to optimise the light embankment piling method through numerical analysis, verified by field and laboratory experiments. The optimisation will mainly focus on pile arrangement and centre-to-centre pile distance.

  • 80.
    Gunnvard, Per
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical Analysis of the Mechanical Behaviour of Light Embankment Piling2017Inngår i: ICSMGE 2017: 19th International Conference on Soil Mechanics and Geotechnical Engineering / [ed] Woojin Lee, Jong-Sub Lee, Hyun-Ki Kim, Dong-Soo Kim, 19th ICSMGE Secretariat , 2017, s. 749-752Konferansepaper (Fagfellevurdert)
    Abstract [en]

    2D and 3D finite element simulations were performed to investigate the mechanical behaviour of the light embankmentpiling method as a pre-study to further develop a new Swedish design guideline. The light embankment piling method is used forsulphide soils and utilises timber piles as its key feature. The Swedish Transport Administration (Trafikverket) recently changed thenational standard of the light embankment piling method from the use of a square to a triangular pile arrangement, based on a theory thata triangular arrangement creates more stable arches in between the piles. The objective with the present study is to evaluate the currentstandard by modelling setups with square and triangular pile arrangements with varying centre-to-centre distance. Both, completelyfloating and semi-floating pile groups were modelled here. The evaluation mainly focused on comparing embankment settlements as wellas axial forces in the piles. No evident difference in the mechanical behaviour between the triangular and the square piling pattern wasfound. The maximum allowed centre-to-centre distance can potentially be increased from 1.2 to 1.5m; resulting in approximately 30% fewer piles used.

  • 81.
    Helm, Jan
    et al.
    Ruhr-Universität, Bochum.
    Laue, Jan
    Ruhr-Universität, Bochum.
    Triantafyllidis, Th.
    Ruhr-Universität, Bochum.
    Zur Verformungsentwicklung von Böden unter zyklischer Beanspruchung2000Inngår i: Bautechnik, ISSN 0932-8351, Vol. 77, nr 6, s. 405-415Artikkel i tidsskrift (Fagfellevurdert)
  • 82.
    Imre, Bernd
    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, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    A centrifuge experiment to derive insight on rock fragmentation within sturzstroms2010Inngår i: Physical Modelling in Geotechnics: Proceedings of the 7th International Conference on Physical Modelling in Geotechnics 2010, ICPMG 2010, 2010, Vol. 2, s. 1253-1258Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This study presents boundary conditions and instrumentation for a centrifuge experiment to simulate fragmentation within a fast moving rock mass as part of a research effort to investigate the thermodynamics of sturzstroms. Sturzstroms are rock slides of very large volume and extreme run out, which display intensive fragmentation of blocks of rock due to inter-particle impacts within a collisional flow regime. The mechanical set up of this physical model delivers a guided experimental rock slide imposed by a dynamic acceleration field. Analogue rock material is stored in a hopper and released in-flight by a pneumatic trap door into an acceleration chute, and progressing to a run out chute. This reflects the prototype situation of a sturzstrom which includes a source, transit, and deposition zone. The instrumentation includes light barriers, a triaxial force sensor, frictional heat sensors, and high and low speed cameras with illumination provided by light emitting diodes. © 2010 Taylor & Francis Group, London.

  • 83.
    Imre, Bernd
    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.
    Fractal fragmentation of rocks within sturzstroms: Insight derived from physical experiments within the eth geotechnical drum centrifuge2010Inngår i: Granular Matter, ISSN 1434-5021, E-ISSN 1434-7636, Vol. 12, nr 3, s. 267-285Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An investigation of the behaviour and energy budget of sturzstroms has been carried out using physical, analytical and numerical modelling techniques. Sturzstroms are rock slides of very large volume and extreme run out, which display intensive fragmentation of blocks of rock due to inter-particle collisions within a collisional flow. Results from centrifugal model experiments provide strong arguments to allow the micro-mechanics and energy budget of sturzstroms to be described quantitatively by a fractal comminution model. A numerical experiment using a distinct element method (DEM) indicates rock mass and boundary conditions,which allowan alternating fragmenting and dilating dispersive regime to evolve and to sustain for long enough to replicate the spreading and run out of sturzstroms without needing to resort to peculiar mechanism. The fragmenting spreading model supported here is able to explain the run out of a fluid-absent granular flow beyond the travel distance predicted by a Coulomb frictional sliding model. This, and its strong relation to internal fragmentation, suggests that a sturzstrom constitutes a landslide category of its own. This study provides a novel framework for the understanding the physics of such sturzstroms.

  • 84.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Direct Simple Shear Tests on Swedish Tailings2018Inngår i: Proceedings of China-Europe Conference on Geotechnical Engineering, Cham: Springer, 2018, Vol. 1, s. 538-541Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Tailings is a waste stream produced by mining industry. It is often stored on the surface in a retaining structure, called tailing impoundment surrounded by tailing dams. Strength property of tailings is important for safety of tailings dam construction. In this study, direct simple shear tests were performed on two Swedish tailings from Malmberget mine and Svappaavare mine in Northern Sweden. The apparatus used is NGI direct simple shear apparatus. The estimated maximal friction angle from shear tests ranged from 15.9 to 24.3°, with cohesions from 0‐16.3 kPa. One phenomenon noticed was that for tailings the sample height started decrease after dilatancy. In order to know whether this is a material property, or it is due to the defect of the simple shear apparatus, a series of shear tests were done on Kalix sand. The result showed that this phenomenon happened also to the densely compacted sand, though more rarely. The decreased sample height after reaching the peak values is assumed to be related to both particle breakage and the deficiency of the shear apparatus.

  • 85.
    Kailey, P.
    et al.
    University of Canterbury.
    Bowman, Elisabeth T.
    University of Canterbury.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Modelling debris flow processes with a geotechnical centrifuge2011Inngår i: International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings, 2011, s. 339-349Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, we examine the effect of flow mass and moisture content on debris flow velocity, discharge, and runout using a series of smallscale flume tests in a geotechnical centrifuge. We found that an increase in mass and an increase in moisture content increased peak velocity during down-slope movement. However, the effect of increased moisture content is much more pronounced than that of increased mass. The maximum cross-sectional area observed did not depend on mass or moisture content, although may have been affected by the flow rate entering the centrifuge. Consequently, flow velocity largely determined the peak discharge of each flow. An increase in moisture content increased the mobility of the flow in terms of depositional area and runout. Further, the runout of the centre of mass of the flows appears to be linearly related to the momentum of flow material entering the flume. © 2011 Casa Editrice Università La Sapienza.

  • 86.
    Kailey, P.
    et al.
    University of Canterbury, Christchurch, New Zealand.
    Bowman, E.T.
    University of Canterbury, Christchurch, New Zealand.
    Laue, Jan
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Modeling Debris flow behavior in a geotechnical centrifuge2011Inngår i: Italian Journal of Engineering Geology & the Environment, s. 339-349Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we examine the effect of flow massand moisture content on debris flow velocity, discharge,and runout using a series of smallscale flumetests in a geotechnical centrifuge. We found that anincrease in mass and an increase in moisture contentincreased peak velocity during down-slope movement.However, the effect of increased moisture contentis much more pronounced than that of increasedmass. The maximum cross-sectional area observeddid not depend on mass or moisture content, althoughmay have been affected by the flow rate entering thecentrifuge. Consequently, flow velocity largely determinedthe peak discharge of each flow. An increasein moisture content increased the mobility of the flowin terms of depositional area and runout. Further, therunout of the centre of mass of the flows appears tobe linearly related to the momentum of flow materialentering the flume.

  • 87.
    Kapogianni, Ekena
    et al.
    National Technical University of Athens.
    Laue, Jan
    ETH Zurich, Institute for Geotechnical Engineering.
    Sakellariou, Michael G.
    National Technical University of Athens.
    Reinforced slope modelling using optical fibre sensors and PIV analysis2010Inngår i: Physical Modelling in Geotechnics: Proceedings of the 7th International Conference on Physical Modelling in Geotechnics 2010, ICPMG 2010, 2010, Vol. 2, s. 1125-1130Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The behaviour of geosynthetic reinforced slope models subjected to self weight loading and impact rockfall event is studied using the geotechnical drum centrifuge of ETH Zurich. Several tests were carried out on wrap-around reinforced sand slopes with a model height of 18 cm and slope inclination 2V:1H. Different reinforcement materials were used with length from 11-19 cm in model scale. In order to define the strain distribution developed along the reinforcement layers during the different loading scenarios, optical fibre sensors were placed at various positions on the geosynthetics sheets. The deformations developed on the slopes have also been measured using digital images and Particle Imaging Velocimetry (PIV) analysis and a comparison of the optical fibre measurements to the PIV analysis measurements is made. In general, the available measurements allow insight in the mechanism acting in the reinforced soil mass and also into the failure mechanism. © 2010 Taylor & Francis Group, London.

  • 88.
    Kapogianni, Elena
    et al.
    National Technical University of Athens.
    Laue, Jan
    Swiss Federal Institute of Technology, Zurich.
    Sakellariou, Michael
    National Technical University of Athens.
    Numerical modelling of centrifuge tests on reinforced slopes2012Inngår i: Geosynthetics: Eurogeo 5 / [ed] Dorte Kuhlmann, CRC Press, 2012Konferansepaper (Fagfellevurdert)
  • 89.
    Kapogianni, Elena
    et al.
    Ethniko Metsovio Polytechnico, School of Rural and Surveying Engineering, Athens, National Technical University of Athens.
    Sakellariou, Michael G.
    Ethniko Metsovio Polytechnico, School of Rural and Surveying Engineering, Athens, National Technical University of Athens.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Springman, Sarah M.
    Institute of Geotechnical Engineering, ETH Hönggerberg, Zürich.
    Investigation of the Mechanical Behaviour of the Interface between Soil and Reinforcement, via Experimental and Numerical Modelling2016Inngår i: Procedia Engineering, ISSN 1877-7058, E-ISSN 1877-7058, Vol. 143, s. 419-426Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this study is to investigate the interface properties between soil and reinforcement, via experimental and numerical modelling of reinforced slopes. In particular, several scale models were built and tested under enhanced gravity in the geotechnical drum centrifuge at ETH Zurich and corresponding prototype numerical models were analyzed via a finite element stress analysis code. Optical fibre sensors were attached on the reinforcement layers of the experimental scaled models in order to measure linear strain during the increase of the g-level, and the results were compared to linear strain that was derived by the numerical analysis of the correspondent prototype reinforced slopes. The interface between soil and reinforcement was expressed in terms of normal and shear stiffness on the soil-reinforcement boundary and different values were tested in order to achieve validation of the experimental and numerical results.

  • 90.
    Kapogianni, Elena
    et al.
    National Technical University of Athens.
    Sakellariou, Michael G.
    National Technical University of Athens.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. ETH Zurich, Institute for Geotechnical Engineering.
    Springman, Sarah M.
    ETH Zurich, Institute for Geotechnical Engineering.
    The use of optical fibre sensors in a geotechnical centrifuge for reinforced slopes2010Inngår i: Physical Modelling in Geotechnics: Proceedings of the 7th International Conference on Physical Modelling in Geotechnics 2010, ICPMG 2010, 2010, Vol. 1, s. 343-348Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this paper is to investigate making strain measurements via optical fibre sensors in a geotechnical centrifuge. This study is part of a test series, which has been carried out in the ETH Zurich geotechnical centrifuge, with the main goal being to investigate the behaviour of reinforced slopes that are subjected, initially, to self weight loading and, subsequently, to impact from a rockfall event. Several reinforced slope models were built with a height of 18 cm and a slope inclination of 2V:1H. The maximum g-level applied was 100 g and the optical fibre sensors were placed on the reinforcement layers at various positions in the model in order to measure the deformations of the reinforcement during the different loading events. © 2010 Taylor & Francis Group, London.

  • 91.
    Kapogianni, Elena
    et al.
    National Technical University of Athens.
    Sakellariou, Michael
    National Technical University of Athens.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Experimental Investigation of Reinforced Soil Slopes in a Geotechnical Centrifuge, with the Use of Optical Fibre Sensors2017Inngår i: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529, Vol. 35, nr 2, s. 585-605Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this experimental investigation is to obtain strain measurements via optical fibre sensors in the drum geotechnical centrifuge of ETH Zurich. It is part of a test series with main goal to study the behaviour of reinforced slopes subjected to self weight loading and subsequently to an impact from a rockfall event. In total 13 scaled reinforced slope models were built with a height of 180 mm and a slope inclination of 2V:1H, optimising the materials used and the different ways of model making. The maximum g-levels were 50 and 100 g and the impact loading was applied at 50 g. The optical fibre sensors were placed on various layers of the reinforcement and at different positions. Strain measurements that were recorded during different tests are logical and expected, demonstrating that optical fibre sensors can successfully be used for measuring linear strain on reinforcement layers that are tested under enhanced gravity in the geotechnical centrifuge. The experimental set up as well as the opportunities and challenges of these measurements are presented and discussed. Finally, correspondent prototype numerical models were created and analysed and the results of this analysis are compared to the corresponding experimental ones.

  • 92.
    Knutsson, Roger
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Viklander, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Geothermal study to explain man-made permafrost in tailings with raised surface2018Inngår i: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 77, nr 7, artikkel-id 288Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Deposition of mine tailings in a cold climate requires precautions as temporary sub-zero temperatures can imply considerable consequences to the storage due to creation of permafrost. The risk of creating man-made permafrost lenses due to tailings deposition exists even in regions with no natural permafrost, as material being frozen during winter might not fully thaw by the following summer. When such frozen layers thaw during later longer warmer periods, excess pore water pressure and large settlements might develop. Such implications close to the dam structure have to be avoided and therefore the risk of generating permafrost should be reduced. This paper describes a geothermal model for one-dimensional heat conduction analysis. The model is able to simulate the temperature profile in tailings where the surface elevation is constantly increased due to deposition. At the tailings surface, the boundary condition is the air temperature changing over time during the year. Air temperatures, tailings deposition schedule and tailings properties are given as input to the model and can easily be changed and applied to specific facilities. The model can be used for tailings facilities in cold regions, where the effects of tailings deposition on the temperature regime are of interest. Findings can improve tailings management by explaining man-made permafrost generation. The model can also aid in setting up appropriate deposition schedules and to prevent generation of permafrost layers.

  • 93.
    Knutsson, Roger
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Viklander, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    How to avoid permafrost while depositing tailings in cold climate2018Inngår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 153, s. 86-96Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Managing tailings deposition in cold climate requires specific measures not to create permafrost. The risk of generating permafrost due to tailings deposition exists even in regions where permafrost would naturally not occur. Material being frozen during winter might not fully thaw in the following summer due to added height of the tailings on the surface. Such embedded layers of permafrost should be avoided especially close to tailing dams. Main reasons are to prevent impermeable layers in tailings facilities, and to reduce the risk of having implications if such layers thaw during warmer summers causing increase in pore water pressure, reduced effective stress, and increased water content.

    This paper presents a numerical study on the effects of tailings deposition in cold regions in relation to the potential formation of permafrost. Various deposition rates, schedules and tailings properties were evaluated. One-dimensional heat conduction analyses were performed with a temperature scenario representing a mine district in northern Sweden. Results show, that the thickness of permafrost layers increase with increased deposition rate and with increased water content. It was also shown that wet and loose tailings must be deposited in short periods during summer to avoid permafrost generation. In the case of dry and dense tailings more time is available for deposition in order not to cause aggradation of permafrost in the deposit.

    These findings can help mining operation to set up deposition schedules for tailings facilities in cold climate. For known tailings properties, results can be used to identify periods of the year when, and how much, tailings can be deposited in critical areas of a deposit in order to avoid permafrost formation.

  • 94.
    Laue, J.
    et al.
    Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Gautray, J.
    Institute for Geotechnical Engineering, ETH Zurich.
    Morales, W. F.
    Institute for Geotechnical Engineering, ETH Zurich.
    Iten, Michael
    Institute for Geotechnical Engineering, ETH Zurich.
    Arnold, André
    Dr. Vollenweider AG.
    15 years of experience using a physical model exercise in a Masters' course2014Inngår i: Physical modelling in geotechnics: proceedings of the 8th International Conference on Physical Modelling in Geotechnics 2014 (ICPMG 2014), Perth, Australia, 14-17 January 2014 / [ed] Christophe Gaudin, Leiden: CRC Press/Balkema , 2014, Vol. 1, s. 445-450Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Modelling in Geotechnics' has been taught for two hours over 14 weeks in the 2nd, and later 3rd, semester of the Masters' studies at ETH Zurich. In addition to a series of frontal lectures on modelling techniques, as well as for their application to various boundary value problems, this course contains an exercise that compares 3 ways of modelling a practical case. Students are invited to investigate a common boundary value problem through complementary analytical, physical and numerical (finite element) modelling. A suitable boundary value problem, such as for shallow foundations or slopes, is selected to ensure that the exercise can be conducted in the limited time available for the students, and that the physical model takes only a finite amount of time so that all students can witness a test from start to finish. A comparison allows the assumptions made for the various models or calculations to be discussed and trains the students to put the different results into perspective. Practical aspects such as feasibility and timing, as well as applicability to reaching the learning goal of the class, will be reviewed. © 2010 Taylor & Francis Group, London.

  • 95.
    Laue, Jan
    ETH Zurich.
    Centrifuge technology2002Inngår i: Constitutive & centrifuge modelling: two extremes, proceedings of the workshop on Constitutive and Centrifuge Modelling: Two Extremes, Monte Verita, Switzerland, 8-13 July 2001 / [ed] Sarah Springman, Boca Raton, 2002, s. 75-112Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Geotechnical centrifuge modelling is used for a wide range of investigations, which cover almost the whole field of geotechnical engineering problems. Independently of the question to be answered, the basis of the centrifuge modelling technique is the assembly of a test set up in a suitable environment. This paper deals mainly with sample preparation and the choice of material to be used, site investigation and characterisation of the soil properties, loading options and transducers, and other ways of obtaining test results as well as scaling laws and differences in the design of geotechnical centrifuges. It finishes with a section on ongoing advances in the development of realistic modelling procedures.

  • 96.
    Laue, Jan
    Ruhr-University Bochum.
    Stability of heaps of iron ore concentrate1997Inngår i: Proceedings of the International Offshore and Polar Engineering Conference / [ed] Chung J.S.,Kim C.H.,Olagnon M.,Naito S., Golden, CO: International Society of Offshore & Polar Engineers, 1997, Vol. 1, s. 921-927Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Caused by the capsizing of a vessel loaded with heaps of wet iron ore concentrate investigations are carried out on the stability of such piles. Geotechnical centrifuge model tests have been conducted in the Bochum geotechnical centrifuge ZI to investigate the stability behaviour of wet iron ore concentrate heaps under static and cyclic loading conditions, representing the movements of the ship. The basic behaviour of the iron ore concentrate is described in comparison with sand in comparable graduation. The parameters for the used materials are evaluated with conventional soil mechanical laboratory tests and also with special tests for the transport of granular materials specified by the Internationale Maritime Organization. More than forty tests were executed in the centrifuge with the help of a newly developed and constructed shaker combining the possibility of imposing vertical and swinging movements under cyclic loading conditions. An additionally constructed swinging bracket allows large angles of rolling. Based on a series of model the model tests, the validity of model laws for the investigation involving cyclic and dynamic problems of wet material are discussed. The findings on the behaviour of wet iron ore concentrate heaps under selfweight conditions, steadily cyclic movements (f.e. rolling of a ship) and sudden movements are shown. Variations of water content, temperature of the material, sample preparation and shape, are correlated to the installation and the behaviour of the heaps on board. With the help of this findings, requirements to reduce the destabilization are formulated.

  • 97.
    Laue, Jan
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Arnold, André
    Institute for Geotechnical Engineering, ETH Zurich.
    Physical modelling of soil: structure interaction of flexible raft foundations2008Inngår i: Foundations: Proceedings of the second British Geotechnical Association International Conference on Foundations / [ed] Brown, Mike J. Bransby, M. F. Brennan, A. J., IHS BRE Press , 2008, s. 1569-1580Konferansepaper (Fagfellevurdert)
  • 98.
    Laue, Jan
    et al.
    ETH Zurich.
    Buchheister, J.
    ETH Zurich.
    Condition indicators for liquefaction susceptibility with focus on silty soils2004Inngår i: / [ed] Triantafyllidis, T, Leiden: Balkema, 2004, s. 489-494Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Deformation of the sub-soil is one of the major risk scenarios being confronted in the event of earthquakes. One of the mechanisms involved in causing large deformations under cyclic loading is liquefaction observed for granular soil conditions. This phenomenon has been studied in a lot of research projects mainly in sandy soils. Recent earthquakes have shown that the range of soils prone to liquefaction is wider than assumed and that the nature of the earthquake has to be regarded as one condition indicator for a soil to reach liquefaction as well. Condition indicators used are based on field investigation or on grain size distribution and Atterberg-limits. Studies on other influencing factors are conducted in the laboratory with cyclic investigations. Among those tests, variations in soil graduation curves are rarely studied. Focus is given mainly to the amount of fines for mostly equivalent void ratios for silty soils. As a reasonable basis for defining condition indicators studies on liquefaction susceptibility of silts and sands with fine contents are reviewed. This review sets the base for an upcoming study in the frame of an interdisciplinary research project on developing a generic method on Management of Risk using condition indicators. The first result of the review leads to the proposal of a dimensionless correlation between the physical state of the soil using the permeability coefficient with a load function. The studies being introduced here will aim to develop an analytical description of liquefaction potential of silty soils to be able to define the condition indicators to subdivide the mechanism leading to strain hardening, strain softening and, in the worst case, liquefaction.

  • 99.
    Laue, Jan
    et al.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Buchheister, J.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Load path and loading velocity as potential condition indicator for liquefaction of silty soils2005Inngår i: Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering: Geotechnology in Harmony with the Global Environment, 2005, Vol. 4, s. 2677-2680Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Condition indicators for liquefaction are mainly given by the soil properties gained from gradation curves and empirically, using relationships between number of SPT blows or CPT results and liquefaction potential. Recent earthquake events as well as recent studies have shown that silty soils, which had been thought to be less prone to liquefaction than sands, are still likely to liquefy. Therefore, the influence of the loading path, and in particular the loading velocity and loading direction, on the liquefaction susceptibility of silty soils will be discussed. It can be deduced that the earthquake profile as well as the boundary conditions related to loading functions have a significant influence on the liquefaction susceptibility. Also liquefaction observed in the field is no t only to be related to the liquefaction of the soil under the free field boundary conditions but the reduction of effective stress during an earthquake has to be regarded in terms of the actual stress interplay in the subsoil. The "starting" conditions as well as the influence of the loading function (frequency and form, stress ratios) will be discussed based on a literature review, which will be enhanced in the future with results obtained with the new cyclic hollow cylinder apparatus. The results will be introduced in a new concept of risk management for earthquakes for buildings and lifelines in an urban environment.

  • 100.
    Laue, Jan
    et al.
    ETH Zurich.
    Grande, L.
    Norwegian University of Science and Technology (NTNU), Trondheim.
    Modelling specific types of geotechnical problems2002Inngår i: Guidelines for the use of advanced numerical analysis, London: Thomas Telford Ltd , 2002, s. 114-137Kapittel i bok, del av antologi (Fagfellevurdert)
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