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  • 301.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Detecting the thickness mode frequency in a concrete plate using backward wave propagation2016Inngår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 139, nr 2, s. 649-657Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Material stiffness and plate thickness are the two key parameters when performing quality assurance/quality control on pavement structures. In order to estimate the plate thickness non-destructively, theImpact Echo (IE) method can be utilized to extract the thickness resonance frequency. An alternativeto IE for estimating the thickness resonance frequency of a concrete plate, and to subsequently enablethickness determination, is presented in this paper. The thickness resonance is often revealed as asharp peak in the frequency spectrum when contact receivers are used in seismic testing. Due to a lowsignal-to-noise ratio, IE is not ideal when using non-contact microphone receivers. In studying thecomplex Lamb wave dispersion curves at a frequency infinitesimally higher than the thickness frequency,it is seen that two counter-directed waves occur at the same frequency but with phase velocitiesin opposite directions. Results show that it is possible to detect the wave traveling with anegative phase velocity using both accelerometers and air-coupled microphones as receivers. Thisalternative technique can possibly be used in non-contact scanning measurements based on aircoupled microphones.

  • 302.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Effect of Surface Unevenness on In Situ Measurements and Theoretical Simulation in Non-Contact Surface Wave Measurements Using a Rolling Microphone Array2015Inngår i: NDT-CE2015 proceedings, Berlin: NDT , 2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Non-destructive seismic testing using air-coupled microphones is today an attractive alternative to the more conventional stationary accelerometer testing, in order to perform fast and reliable material characterization on pavement structures. A multichannel microphone array enables fast mobile data collection using a rolling trolley. It is essential that the microphone array and the material surface are perfectly aligned to receive a correct result. This study presents estimations of the calculation errors due to misalignments between the microphone array and the material surface. It is shown that even small misalignments can cause large errors. A realistic pavement roughness is simulated in order to quantify the errors in different situations and for different materials (stiffness). A simple solution to correct the errors under certain circumstances is also presented.

  • 303.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Effect of surface unevenness on non-contact surface wave measurements using a rolling microphone array2015Inngår i: 41ST ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION: Volume 34 / [ed] Dale E Chimenti and Leonard J. Bond, American Institute of Physics (AIP), 2015, Vol. 1650, s. 128-135Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Surface wave velocity is measured and evaluated along a straight survey line in order to compare two different data acquisition methods. Results from a rolling microphone array are compared to data acquired using a conventional accelerometer. Results from the two different data acquisition methods are shown to be similar. However, it is demonstrated that the results are very sensitive to misalignments between the microphone array and the measured surface. Practices to overcome problems with misalignments are discussed and demonstrated.

  • 304.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Vägtekniks laboratorium.
    Non-contact rolling surface wave measurements on asphalt concreteInngår i: International Journal on Road Materials and Pavement Design, ISSN 1468-0629, E-ISSN 2164-7402Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Rolling surface wave measurements on a single, thin asphalt concrete (AC) layer arepresented to investigate their use in rapid nondestructive field tests. An array of 47 micro-electromechanicalsensor (MEMS) microphones is mounted on a trailer together with an automated impactsource. Multichannel recordings from single impacts are obtained at 80 equally spaced positions as thetrailer moves at a constant speed. The complete battery-powered data acquisition system enables largescaletesting of newly built pavements. Multiple sets of test results show good repeatability for theassessed shear wave velocity and demonstrate the strong temperature dependency of AC. The presentedresults indicate a possible application for quality assurance of AC using rolling surface wavemeasurements.

  • 305.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Birgisson, Björn
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Non-contact surface wave testing of pavements: comparing a rolling microphone array with accelerometer measurements2016Inngår i: Smart Structures and Systems, ISSN 1738-1584, E-ISSN 1738-1991, Vol. 17, nr 1, s. 1-15Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rayleigh wave velocity along a straight survey line on a concrete plate is measured in order to compare different non-destructive data acquisition techniques. Results from a rolling non-contact data acquisition system using air-coupled microphones are compared to conventional stationary accelerometer results. The results show a good match between the two acquisition techniques. Rolling measurements were found to provide a fast and reliable alternative to stationary system for stiffness determination. However, the non-contact approach is shown to be sensitive to unevenness of the measured surface. Measures to overcome this disadvantage are discussed and demonstrated using both forward and reverse rolling measurements.

  • 306.
    Björklind, Malin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Soil profile analysis by vibration theory and the natural frequency: Applied on a case project2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    To explore soil conditions at sites of infrastructure projects a number of geotechnical soundings are performed at appropriate intervals. Results are, in the nature of their set up, limited to the specific points at which the sounding is performed. To safely assume the area between bore holes a new method is applied and tried at the case railroad project Stenkumla – Dunsjö. By applying vibration theory in conjunction with the studied soils’ geodynamic properties the natural frequency for the soil can be calculated. The properties of the natural frequency also makes it possible to detect in vibration measurements. The method studied in this master thesis is that of utilizing the natural frequency of the soil to try and establish a soil profile from vibration measurements.  An important step in the method is to transform the vibration with the Fast Fourier Transform algorithm. This allows the comparison and analysis of natural frequencies. The measurements were performed by using and attaching an accelerometer to a train.  Results are partly transformed measurement data in frequency graphs and partly natural frequency calculations according to the site investigations. These are compared in the analysis section to try to confirm the methods’ reliability and to see if the method can be used to refine geotechnical investigations.  The reliability of the method is tested by watching for the expected frequencies from the calculations in the measurement data.  The method show more consistency closer to the ground surface rather at greater depths. It is also more reliable for stark contrast layers, i.e. if the soil layers have much of the same properties then it is difficult to spot the differing natural frequencies, as they are too similar.  In trying to establish the soil profile between bore holes the method is inconclusive, partly due to the fact that the investigated area consists of relatively alike soil layers that make the result graphs difficult to get information from. However, the suggested soil profiles from the analysis of this part of the master thesis bear resemblances to bore holes close by, so the method can be usable in some regard. Quality of measurement results would probably be better by running the train faster than was done in this master thesis. The quality of the analysis would also benefit from performing specific soundings to establish the soils’ geodynamic properties rather than using recommended empirical formulas as were used here.  The primary possible application for this method is to use it as a prioritizing tool at an early stage in infrastructure projects. Running the vibration measurement and getting a preliminary picture of the soil conditions could act as a way of steering investigations resources to where greater shifts in the data occur. 

  • 307.
    Björkman, Rasmus
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Jabbar, Atheer
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Partialkoefficientmetodens applicerbarhet på dimensionering av sprutbetong mot enskilda block: Fallstudie: Citybanan i Stockholm2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Målet med det här examensarbetet var att undersöka hur väl dagens partialkoefficienter för sprutbetong tar hänsyn till samhällets normer och säkerhetskrav vid dimensionering enligt partialkoefficientmetoden. Det brottfall som har undersökts för dimensionering av sprutbetong är vidhäftningsbrott vid god vidhäftning. Vidhäftningsbrottet har undersökts med hjälp av en sannolikhetsbaserad metod benämnd ”First-Order Reliability Method”, FORM. Metoden förutsätter kännedom om sannolikhetsfördelningar för ingående variabler i brottgränstillståndet som i det här arbetet till stor del baserats på provtagningar från projektet Norrströmstunneln i Citybanan.

    Resultatet av undersökningen visar att partialkoefficienterna antar otillåtna värden för dimensionering av sprutbetong på grund av den stora spridningen som råder i framförallt vidhäftningsparametern. Vidhäftningsparametern antog en normalfördelning med medelvärde 0.808 MPa och standardavvikelse 0.319 MPa vid analys av samtliga vidhäftningsmätningar. Spridningen för vidhäftningsparametern har reducerats genom att undersöka gnejs och granit var för sig och genom att ta bort mätningar där dålig vidhäftning i förväg kunnat antas. För granit fick vidhäftningsparametern ett medelvärde på 0.759 MPa och en standardavvikelse på 0.264 MPa. För gnejs fick vidhäftningsparametern ett medelvärde på 0.820 MPa och en standardavvikelse på 0.279 MPa. I den här fallstudien resultera en reducerad spridning för vidhäftningsdata inte i någon avgörande skillnad för beräknade partialkoefficienter.

    Modellen för vidhäftningsbrottet verkar tillsynes inte vara för komplicerad men det existerar samtidigt stora osäkerheter i modellen och ingående variabler gällande laster och bärförmågor. Framförallt okunskapen gällande lastvariabeln gör det svårt att kalibrera relevanta partialkoefficienter med FORM.

  • 308.
    Blom, Roger
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för naturvetenskap, lantmäteri- och maskinteknik.
    Höglund, Annika
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för naturvetenskap, lantmäteri- och maskinteknik.
    Konsekvensredovisning vid detaljplanering: En studie av planer enligt nya PBL2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Till stor del bygger samhällsplanering på förändring och utveckling av den fysiska miljön, vilket närboende kan ha olika synpunkter på. För att uppnå acceptans vid en förändring är det viktigt att berörda känner delaktighet i processen samt att informationen är tydlig och begriplig även för den som inte är kunnig inom området. Vid framtagande av en detaljplan ska planbeskrivningen ange de organisatoriska, tekniska, ekonomiska och fastighetsrättsliga åtgärder som krävs för dess tänkta genomförande. För att de berörda fastighetsägarna ska kunna läsa och förstå hur de påverkas av en detaljplan måste planbeskrivningen tydligt och begripligt redovisa det tänkta genomförandets konsekvenser.

    Syftet med studien är att få svar på i vilken omfattning konsekvensredovisning av genomförandefrågor förekommer och om kraven i 2011 års Plan- och bygglag (PBL) kan anses vara uppfyllda. PBL-kommittén konstaterar år 2005 att beskrivningarna av genomförandet av detaljplaner många gånger är bristfälliga eller saknas helt. Införandet av en ny PBL den 2 maj år 2011 syftade bland annat till att stärka genomförandefrågornas status. I studien undersöktes omfattningen av redovisningen med avseende på organisatoriska, tekniska, ekonomiska och fastighetsrättsliga frågor samt om redovisningen sker summariskt eller fastighetsvis. Studien omfattar 84 detaljplaner från Västra Götalands och Stockholms län som var i granskningsskedet under vecka 14 och 15, år 2014. För att få en bild av tillämpningen av 2011 års PBL 4:33 § skapades 19 frågor. Till dessa frågor togs ett antal kategorier/svarsalternativ fram som användes för att klassificera innehållet i planbeskrivningarna. Resultatet visar att det förekommer en stor variation på omfattningen av konsekvensredovisning i planbeskrivningen. Ett genomsnittligt värde på hur vanligt det är med bristfällig konsekvensredovisning (i de applicerbara fallen) i respektive huvudgrupp ger följande resultat:

     Organisatoriska frågor: 49 %

     Tekniska frågor: 30 %

     Ekonomiska frågor: 68 %

     Fastighetsrättsliga frågor: 13 %

    Studien visar också att fastighetsvis redovisning förekommer i mycket begränsad omfattning. Med ovanstående resultat är det tveksamt om ett flertal av detaljplanerna uppfyller lagens krav på redovisning och skulle klara en prövning i domstol

  • 309.
    Bodare, Anders
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Markvibrationer från järnvägstrafik2006Inngår i: Bygg & teknik : Sveriges äldsta byggfacktidning, ISSN 0281-658X, nr 2, s. 47-52Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Problem med markvibrationer från järnvägstrafik har funnits sedan järnvägar först togs i bruk. Redan Lord Rayleigh deltog i en kommission som studerade både mark- byggnadsvibrationer i London i början av nittonhundratalet. De senaste tre decennierna sett ett ökat intresse, i hela Europa, för järnvägens vibrationsproblem, en ökning som fortsätter allt snabbare. Stora projekt pågår för närvarande i England, Holland, Frankrike, Tyskland och i viss mån också USA, Italien och Tjeckien, förutom också i de Nordiska länderna, Norge, Finland, Danmark och Sverige. Just nu pågår andra fasen av ett internordiskt projekt kallat NordVib.

  • 310.
    Bodare, Anders
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Vibrationsutbredning i berg och jord vid sprängning2007Konferansepaper (Annet vitenskapelig)
  • 311.
    Bodare, Anders
    et al.
    Geo Risk & Vibration Scandinavia.
    Massarsch, Rainer
    Geo Risk & Vibration Scandinavia.
    Wersäll, Carl
    Geo Risk & Vibration Scandinavia.
    Planning and Execution of Rock Blasting in Urban Areas2009Inngår i: Environmental Vibrations: Prediction, Monitoring, Mitigation and Evaluation / [ed] H. Xia & H. Takemiya, 2009, s. 784-789Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Proper management of technical risks during blasting facilitates efficient project management and helps keeping costs and safety at an acceptable level. it is of crucial importance to incorporate the process of risk management in the design and execution of the project. Risk analyses of the environmental effect of blast-induced vibrations are, in many cases, based on crude concepts which do not take into consideration the fundamental nature of vibratory motion. Realistic modeling of wave propagation in soil and rock requires that correct dynamic parameters are considered and appropriate attenuation models are applied. It is possible to apply relatively simple vibration attenuation concepts for prediction of vibrations in soil and rock and their interaction with structures on or below the ground surface.

  • 312.
    Bolinder, Adam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    CPT-sondering och trycksondering, en jämförande studie om utvärdering av friktionsvinkel i friktionsjord2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Knowledge of the soils friction angle is necessary to avoid landslides at slope stability surveys and dimensioning for foundation of different constructions. Frictional forces mainly builds up friction soil and the friction angle is defined by the angle when landslides occur. Friction angle can be evaluated using CPT or pressure probe. Both methods are performed similarly, with constant pressure and sink rate, but differ in time, cost, competence requirements and number of measurable parameters. The methods also differ when evaluating the friction angle. For CPT, the Conrad software is used while pressure probe is evaluated with empirical values, set against the peak pressure. This degree project compares the results from performed and evaluated CPT and pressure probes from several drill points in a project. The purpose of the study is to draw conclusions about the soils friction angle, whether the empirically evaluated values of the friction angle by pressure probing, can be correlated with the values of the friction angle through CPT, evaluated with the Conrad software. Both CPT and the evaluation with Conrad are more advanced methods and are therefore seen as the correct value for the soils friction angle. The result shows that pressure probe provides a good indication when evaluating the friction angle and can be used, with the knowledge that the friction angle is rarely evaluated higher than from CPT. The methods differ the most towards the surface to almost correlate towards the depth.

  • 313.
    Bolton, Malcolm D.
    et al.
    University of Cambridge, Department of Engineering.
    Gui, Meen-Wah
    National Taipei University of Technology, Department of Civil Engineering.
    Garnier, Jacques Ph
    Laboratory Cent. Ponts & Chaussees, Nantes.
    Corté, Jean François
    Laboratory Cent. Ponts & Chaussees, Nantes.
    Bagge, G.
    Technical University of Denmark, Lyngby.
    Laue, Jan
    Ruhr-Universität, Bochum.
    Renzi, R.
    ISMES Istituto Sperimentale Modelli e Strutture, Bergamo.
    Centrifuge cone penetration tests in sand1999Inngår i: Geotechnique, ISSN 0016-8505, E-ISSN 1751-7656, Vol. 49, nr 4, s. 543-552Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    When performing centrifuge tests, it is necessary to carry out in-flight tests such as the cone penetration test (CPT). Recently, miniature CPTs have formed one collaboration entitled 'European Program of Improvement in Centrifuging' (EPIC). This article provides information on both the random and the consistent variations which have been observed with CPTs in sand when identical prototypes have been modeled in the different laboratories.

  • 314. Bondarchuk, Alexander
    et al.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dahlström, Lars-Olof
    Nordlund, Erling
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hydromechanical numerical analysis of rock mass behavior under a Swedish embankment hydropower dam2009Inngår i: Long Term Behaviour of Dams: Proceedings of the 2nd International Conference, 12th-13th October 2009, Graz, Austria / [ed] Erich Bauer; Stephan Semprich; Gerald Zenz, Graz: Verl. der Techn. Univ. Graz , 2009, s. 113-118Konferansepaper (Fagfellevurdert)
  • 315.
    Bonthron, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Jonsson, Christian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Geogrids in cold climate: Temperature controlled tensile tests & Half-scale installation tests at different temperatures 2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Due to the findings of extensive damage on geogrids used in a road embankment in northern Sweden, the Swedish Transport Administration (TRV) started to investigate the reason of these damages. Since the geogrids were installed at low temperature, below 0°C, it was suspected that the damages were connected the low temperature.

    To analyse whether low temperatures have an influence on the extent of installation damages, both a half-scale setup and temperature controlled tensile tests have been carried out on geogrids.

    In total five different types of geogrids have been tested; 3 extruded polypropylene geogrids, 1 woven PET geogrid, and 1 welded PET geogrid. All geogrids had an aperture size of approximately 35 mm and specified tensile strength of approximately 40 kN/m.

    The Half-scale tests was conducted by building a small road embankment inside a freeze container, at the Luleå University of Technology (LTU). The embankment contained crushed aggregate, type 0-70 mm, and geogrids. The purpose of the half-scale test was to simulate installation of geogrids at different temperatures and thereby investigate whether low temperatures have an influence on the rate of installation damages.

    The half-scale test was done for each type of geogrid at the temperatures: +20°C, -20°C and -30°C. First, the geogrid was covered by 150 mm of crushed aggregate. Then a vibratory plate (160 kg) was used to compact the crushed aggregate. After each installation, the crushed aggregate was removed carefully by vacuum suction. The geogrid was removed and then analysed by visual control and tensile tests conducted according to ISO 10319:2008 (wide width tensile test).

    Results from the half-scale tests indicate that 2 out of 5 of the tested geogrids were affected by the testing procedure. The results indicate that:

    -        one of the geogrids of polyprophylene (here referred to as G2) was more damaged at lower temperatures compared to installation at +20° C.

    -        the geogrid of woven PET (here referred to as G5) was less damaged at lower temperatures compared to installation at +20° C.

    Results for the other geogrids are either inconsistent or shows no significant variation of the measured parameters as function of temperature. Hence, these results cannot be interpreted as damage during installation.

    Temperature controlled tensile tests were done by tensile testing single strands from the geogrids to failure, inside a temperature controlled chamber. The purpose of these tests was to investigate how the strength properties of the geogrids are affected by low temperature. The test was repeated 5 times for each geogrid and temperature (+20°C, 0°C, -10°C and -20°C). Force and strain was measured during the tests.

    The results from the temperature controlled tensile tests show that the maximum strain decreases with lower temperature for all tested geogrids. The maximum strain decreased by 16% - 49% when the temperature dropped from +20°C to -20°C.

    The results show that the tensile strength increases with lower temperature for all tested geogrids except for the welded PET geogrid (here referred to as G1). For G1 the tensile strength decreased by approximately 7% at a temperature drop from +20°C to -20°C.

    For the woven PET geogrid (G5) and the polypropylene geogrids (G2-G3) the tensile strength increased between 13%-45% at a temperature drop from +20°C to -20°C.

    The E-modulus increased at lower temperature for all tested geogrids. The secant E-modulus at 2% strain increased by 13%-71% at a temperature drop from +20°C to -20°C.

    Summarized conclusions from the tests:

    Strength properties changed for all tested geogrids as the temperature decreased. All tested geogrids got stiffer at lower temperatures. The magnitude of the effects is different for different geogrids.

    The tensile strength increased with lower temperature for all tested geogrids except for the welded PET geogrid, which got lower tensile strength at lower temperature.

    The half-scale test indicates that the amount of installation damages at geogrids can be dependent of the temperature at installation. However, these indications can only be seen at two out of five tested geogrids. The effect cannot be connected to a specific step in the installation procedure and cannot be explained by the results from the temperature controlled tensile tests.

    The results from the half-scale test have a statistically low reliability since only one installation for each temperature and geogrid type was done. The compaction equipment used during the test was small, and had low compaction energy compared to a vibratory roller compactor commonly used in construction work.

    With respect to the discussion above, further studies should be focusing on developing the half-scale test. It is suggested that the test is scaled up to a full-scale test in order to simulate a real installation as close as possible. The test should also be conducted several times for each geogrid at each temperature in order to enable statistical analyses.

  • 316.
    Bouchelaghem, Fatiha
    et al.
    Sorbonne Universites, UPMC Univ Paris .
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Fluid flow and effective conductivity calculations on numerical images of bentonite microstructure2017Inngår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 144, s. 9-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hydraulic conductivities of compacted water-saturated bentonite were computed based on the real microstructure. The Homogenization of Periodic Media approach employed fully acknowledges the heterogeneous and multiscale microstructure of clay, as well as locally varying physical flow properties. Consequently, three levels of description were considered : the microscopic level of clay particles, the mesoscopic level of clay aggregates, mineral grains and inter-aggregate porosity, and the macroscopic level of the sample subjected to fluid pressure gradients in the laboratory. Starting from the local description of fluid flow, the expression of the effective hydraulic conductivity tensor was derived. The soft and dense gels and the open voids may form a connected flow path or remain occluded. The local problems were solved on the microstructure obtained from a digitalized micrograph by image analysis. The contribution to macroscopic flow by the soft and dense gels was investigated in various configurations, and comparisons were made with hydraulic conductivity data for MX-80 bentonite.

  • 317.
    Bowman, Elisabeth T.
    et al.
    Department of Civil and Natural Resources Engineering, University of Canterbury.
    Imre, Bernd
    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.
    Experimental modelling of debris flow behaviour using a geotechnical centrifuge2010Inngår i: Canadian geotechnical journal (Print), ISSN 0008-3674, E-ISSN 1208-6010, Vol. 47, nr 7, s. 742-762Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Physical modelling of debris flows has been carried out in the geotechnical drum centrifuge at ETH Zürich. A new apparatus to model debris flows in the centrifuge is described. The apparatus permits the final reach of a typical debris flow to be modelled within the centrifuge, with unconsolidated material flowing down a slope to deposit as a fan around the drum. Experiments are described for both fixed base conditions and erodible bases. Tests to examine the verification (modelling) of models show that debris flow behaviour is governed mainly by friction and consolidation processes, although some resolution is required between flow behaviour downslope and flow arrest during runout. The results are compared with bulk parameters determined for field-scale debris flows. It is found that some important flow mechanisms, such as contact-dominated behaviour and high pore pressures, are developed that are closer to those developed at fieldscale than tests conducted at 1g. Velocity profiles for erodible beds are compared with a semi-empirical expression derived for experimental debris flows at 1g. Normalized velocity profiles are found to be in agreement; however, absolute velocities differ from those predicted. Scaling, the limitations of the apparatus, and potential for future work are discussed

  • 318.
    Bowman, Elisabeth T.
    et al.
    University of Canterbury.
    Imre, Bernd
    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.
    Geotechnical centrifuge modelling of debris flows2007Inngår i: International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings, 2007, s. 229-239Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A granular debris flow may grow in size through erosion of its substrate, resulting in an increased hazard through greater mass, speed and runout. Exactly what governs the erosion potential of a particular flow is a matter of some debate, however, with apparently similar conditions producing very different entrainment behaviour. Some theories use an extension of sediment transport models that involve the removal of soil through a shear stress applied by the flow. However, comparison of field and laboratory-scale data suggests that other processes, such as undrained loading of the bed, are also likely to have influence at large scales. Hence properties of the bed need to be considered as well as the characteristics of the flow material. The modelling of erosion processes at laboratory scale is generally limited by the low stresses applied by the soil-water mixture at small scale. Modelling flows in a geotechnical centrifuge overcomes this problem by increasing the g-level, therefore allowing for correct prototype stress levels to be accounted for at small scale. This paper describes the development and use of a model debris flow apparatus on a geotechnical drum centrifuge at ETH in Zurich, Switzerland. Preliminary tests have been undertaken to compare fixed and erodible bed conditions - enabling erosion processes to be examined at prototype stress levels. © 2007 Millpress.

  • 319.
    Bowman, Elisabeth T.
    et al.
    University of Canterbury.
    Laue, Jan
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Imre, Bernd
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Zweidler, Adrian
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Debris flows in a geotechnical centrifuge2006Inngår i: Physical Modelling in Geotechnics, 6th ICPMG'06: Proceedings of the 6th International Conference on Physical Modelling in Geotechnics, 2006, Vol. 1-2, s. 311-316Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A new apparatus to allow the examination of laboratory debris flows at prototype stress levels within a geotechnical drum centrifuge is described. The apparatus consists of a curved aluminium flume that lies within the circumference of the drum, the inclination of which can be altered from 0 to 40 degrees. PPTs may be placed in the base and along one aluminium side wall, while the other wall is made from Perspex, to enable viewing of the flow during a test. A tube at the head of the flume enables flow materials to be introduced after preparation external to the centrifuge, while tests may be carried out with both fixed and erodible beds. A high speed camera is used to capture images of the flow during centrifuge flight. Initial tests suggest a maximum particle size of 4mmmay be introduced to the flow.The influence ofwater content and fluid viscosity is discussed. © 2006 Taylor & Francis Group, London.

  • 320.
    Brenot, Agnès
    Luleå tekniska universitet.
    Finite element simulation on Abaqus of the freezing of polluted sediment2002Rapport (Annet vitenskapelig)
    Abstract [en]

    Frigeo is working on an innovative technique to remove polluted sediments by freeze dredging. This method presents many advantages: the cost of the process is reduced compared to traditional methods and it is environmentally friendly. Now Frigeo would like to develop the simulation of the freezing process to improve the different parameters of the freeze cell and to evaluate the time necessary to freeze a certain soil. Frigeo is testing at the moment a layout of seven freeze cells, constituted by seven freeze pipes each, to remove polluted sediments. The work presented in this Master thesis is focused on the finite element simulation on Abaqus of the freezing of polluted sediments. The program developed on Abaqus in this present work, has permitted to simulate the three-dimensional temperature distribution around one freeze cell progresses with the time. The first part of the work has consisted of generating an appropriated finite element mesh with the software FEMGV6 to represent the particular geometry studied in this Master thesis. The simulations are quite accurate compared to the theoretical solution in one dimension and the field experiments carried out on sand by Frigeo to test the program developed on Abaqus. Thus, the simulations computed in this work give an accurate estimation of the total time of freezing. The thermal properties of the soils have been tested in order to determine their influence on the simulations. For all the soils with a thermal diffusivity a greater than 5*10-7 m2/s, we obtain the same kind of temperature repartition, which implies that the variation of a with the temperature during the freezing process doesn't affect the results of the simulations. It has been proved also that the computations are quite independent from the variations of the value of the latent heat. With the results of this work, Frigeo is now capable to numerically test the freeze dredging method, to improve the different parameters of the process as well as to make a cost estimation of it.

  • 321.
    Brundin, Herman
    et al.
    SÖRAB.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rihm, Thomas
    RVF service AB.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Tham, Gustav
    Telge Återvinning AB.
    Långtidsegenskaper hos tätskikt innehållande bentonit2001Rapport (Annet vitenskapelig)
    Abstract [sv]

    Bentonit är en starkt vattenupptagande och svällande naturlig lera med låg vattengenomsläpplighet. Huvudkomponenten är mineralet montmorillonit, som tillhör gruppen smektiter och som ger bentoniten dess unika egenskaper. Syftet med uppdraget är att söka identifiera vilka mekanismer och faktorer som kan vara begränsande för funktionen på kort och lång sikt hos tätskikt innehållande bentonitmattor samt blandningar av bentonit och andra material. I rapporten ges underlag för projektering, utformning och drift av deponier med tätskikt innehållande bentonit. Där redovisas också tre fallstudier från Högbytorp, Löt och Tveta.

  • 322.
    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)
  • 323.
    Buchheister, J.
    et al.
    ETH Zurich.
    Laue, Jan
    ETH Zurich.
    Frist results of cyclic experiments using a hollow cylinder apparaturs2006Konferansepaper (Fagfellevurdert)
  • 324.
    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.

  • 325.
    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.

  • 326.
    Buck, Sine
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad.
    Determining the best location for a nature-like fishway in Gavle River, Sweden2013Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The construction of dams and hydro-power stations are some of the most common anthropogenic changes of watercourses and rivers. While being important to humans and society by providing electricity, these obstructions of watercourses can have severe consequences for the aquatic ecosystems. One consequence is that dams often hinder the important movement of migrating fish species between habitats. This can lead to decline and even extinction of important fish populations. To prevent these negative effects, a number of different fish passage systems, including nature-like fishways, have been developed. Nature-like fishways mimic natural streams in order to function as a natural corridor for a wide range of species. Planning and construction of a nature-like fishway is a complex task that often involves many different interests. In the present study a combination of multi-criteria decision analysis and least-cost path analysis is used for determining the best location for a nature-like fishway past Strömdalen dam in Gavleån, Sweden. An anisotropic least-cost path algorithm is applied on a friction-layer and a digital elevation model, and the least-cost path for a nature-like fishway is determined. The results show that the method is useful in areas of varying topography and steep slopes. However, because low slope is a very important factor when constructing a nature-like fishway, slope becomes the dominating factor in this analysis at the expense of e.g. distance to roads. Combining the methods with results from biological studies of fish behavior and detailed hydrological modelling would provide a very strong tool for the planning of nature-like fishways.

  • 327.
    Burefalk Strauss, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Rosko, Samuel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Fastställande av lineamentens karaktär med avseende på bergkvalitet enligt Qbas och RMRbas inför tunnel-konstruktion i Solna, Stockholm samt kvalitetsutvärdering av Astrock hyperdata report2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Sweden's population is increasing every year, which means that cities must adapt their infrastructure to be able to follow the demographic trend. In the current situation, Stockholm plans a major expansion of its metro network where evaluating the bedrock quality is of paramount importance. For the new SL metro connection project Gula linjen that stretches between Odenplan and Arenastaden in Solna, the company WSP has previously done quality surveys of the bedrock in the area and dimensioning of the reinforcements in the planned tunnels. Previous survey of the lineaments and weakness zones in the area has been done by means of core drilling and observations in the field. This study examines if the lineaments in the area are associated to any structures below ground surface in the bedrock by examining rock samples from drill cores. A digital presentation tool called Astrock hyperdata report is evaluated in this study by comparing manual measurements of the orientation of the joints in drill cores and the software´s measurements. The studied bedrock in the drill cores varies in quality from very poor to very good. Further examinations of zones of particularly poor rock quality done in this study suggest that the two identified lineaments have different characteristics. The north-west/south-east lineament which runs parallel to the planned metro route is indicated to represent the surface trace of a water-bearing fracture zone in the bedrock. The lineament with the E/W direction is dominated by structures and fault rocks, such as fault gouge and crushed rock in the drill cores, which indicates a brittle deformation zone. For the Gula linjen project, this information becomes useful as the underground reinforcements such as bolting and grouting have to

  • 328.
    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

  • 329. Bylund, Anders
    et al.
    Lindmark, Martin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kommunal och enskild väghållning: kostnader, utförande, standard - etapp 11988Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Denna rapport behandlar metoder för uppföljning av kostnader och standard för vinterväghållning.

  • 330.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Comparison of hydraulic backfill measurements with results from FEM calculations1981Inngår i: Application of rock mechanics to cut and fill mining: proceedings of the Conference on the application of rock mechanics to cut and fill mining, organized by the Departments of rock mechanics and soil mechanics, University of Luleå ... held at the University of Luleå, Sweden, from 1 to 3 June, 1980 / [ed] Ove Stephansson; Michael J. Jones, London: The Institution of Mining and Metallurgy , 1981, s. 269-271Konferansepaper (Fagfellevurdert)
  • 331.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Influence of testing method and testing technique on the measured properties of silty soils1982Inngår i: Quality of mechanical observations on particulate media: Lyngby, Denmark, Aug. 18-20, 1982 / [ed] V. Askegaard, Lyngby: Technical University of Denmark , 1982, s. U.1-U.5Konferansepaper (Fagfellevurdert)
  • 332.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Mechanical properties of hydraulic backfill1981Inngår i: Application of rock mechanics to cut and fill mining: proceedings of the Conference on the application of rock mechanics to cut and fill mining, organized by the Departments of rock mechanics and soil mechanics, University of Luleå ... held at the University of Luleå, Sweden, from 1 to 3 June, 1980 / [ed] Ove Stephansson; Michael J. Jones, London: The Institution of Mining and Metallurgy , 1981, s. 193-203Konferansepaper (Fagfellevurdert)
  • 333.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Mechanical properties of inorganic silt1981Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The need for increased knowledge of the properties and behaviour of silty soils has been urgent for many years. This report is an attempt to fulfil this need to same degree. The properties of inorganic silt have been investigated by means of laboratory tests, field tests and load tests. The investigations have primarily concerned drained and undrained shear strength parameters and their use for real cases of load. The mechanisms of failure and the components of friction and shear strength are discussed. The influence of failure criteria, testing method, and rate of shear on the shear strength parameters have been studied as well as the influence of clay content, plasticity index, deformation to failure, and stress history. The testing methods and parameters have been checked with some load tests in the field and in the loading basin.

  • 334.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Shear strength of inorganic silty soils1981Inngår i: Soil mechanics and foundation engineering: proceedings of the Tenth international conference on soil mechanics and foundation engineering, Stockholm 15-19 June 1981., Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1981, Vol. 1, s. 567-572Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Deals with the shear strength of silt measured in the laboratory with special reference to the influence of the testing technique. Drained and undrained shear conditions have been considered and much attention has been paid to the angle of friction and its relation to the strain at failure. The influence of time and stress history has also been investigated

  • 335.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Stability of partially drained excavated slopes in silty soils1984Inngår i: Canadian case histories: landslides: Preprint volume for the 37. Canadian Geotechnical Conference organized jointly with the 4. International Symposium on Landslides, Toronto: University of Toronto Press, 1984, s. 241-245Konferansepaper (Fagfellevurdert)
  • 336.
    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, s. 343-350Konferansepaper (Fagfellevurdert)
  • 337.
    Börgesson, Lennart
    Luleå tekniska universitet.
    Stress-strain relationships for silty soils1978Rapport (Annet vitenskapelig)
  • 338.
    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, s. 229-237Artikkel 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.

  • 339.
    Börgesson, Lennart
    et al.
    Luleå tekniska universitet.
    Axelsson, Kennet
    Luleå tekniska universitet.
    Stress-strain-strength behaviour and its modelling for silty soils1980Rapport (Annet vitenskapelig)
  • 340.
    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.

  • 341.
    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.

  • 342.
    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, s. 16s. 382-388Artikkel 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.

  • 343.
    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)
  • 344.
    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.

  • 345.
    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, s. 609-615Konferansepaper (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

  • 346.
    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, s. 33-35Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 347.
    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.

  • 348.
    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.

  • 349.
    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, artikkel-id 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.

  • 350.
    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, s. 123-141Artikkel 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.

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