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  • 151.
    Altaie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Estimation of Settlement under Shallow Foundation for Different Regions in Iraq Using SAFE Software2015Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, nr 7, s. 379-386Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Foundation design must satisfy limited values of settlement. Settlement is an essential criterion in the design process of shallow foundations. To calculate the settlement under different types of shallow foundations, 79 samples were taken from twenty-three sites distributed in three regions:Mosul, Baghdad and Basrah in the northern, central and southern parts of Iraq. Field and laboratory tests were performed to obtain the strength parameters to calculate the bearing capacity. The results obtained for the bearing capacity were used in SAFE software. The software was used to design and analyze the foundation and to calculate the settlements under two types of foundations (raft and continuous) for the three regions. Average and minimum values of bearing capacity wereused. The software used subgrade reaction modules values for the design and analysis. According to the results, the suitable, safe and economical type of foundation to be used in Mosul, Baghdad and Basrah regions for the average value of bearing capacity is the continuous type for the first two regions while the raft type is recommended for Basrah region. In case that the minimumbearing capacity values are used, raft foundation is recommended for Mosul and Baghdad. While deep foundation is the suitable type of foundation for Basrah region.

  • 152.
    Al-Taie, Entidhar
    et al.
    Reconstruction and Projects Department, Minister of Higher Education and Scientific Research, Baghdad.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of Foundation Settlement under Various Added Loads in Different Locations of Iraq Using Finite Element2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 5, s. 257-268Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Settlement is an important criterion in the design of the foundations. It is classifying into immedi-ate (or elastic) settlement and consolidated settlement (primary and secondary). The factors that affect the shallow foundation settlement are the applied loads, soil stiffness, and geometric shape of foundation. Calculations of settlement depend on the parameters of soil which can be obtained from field and laboratory tests. Field and laboratory tests were conducted for twenty three sites in three different regions in Iraq (Mosul, Baghdad, and Basrah). In this research, field and laboratory tests results adopted for two sites from each region depended on the maximum and minimum bearing capacity values. Settlement for each site was calculated using numerical (mathematical) calculations and PLAXIS software under different added loads. The results of settlements beneath the foundation were competing for the sites with maximum value of bearing capacity in Mosul; Baghdad and Basrah. Also, the comparison conducted for sites of minimum bearing capacity value and the results showed different settlement values of each site. The change of settlement values under different loads was linearly in the six sites using numerical (mathematical) calculations. While, the settlement values obtained from PLAXIS software for sites with maximum bearing ca- pacity value showed that Mosul site had the highest value due to the type of soil layers and the dif- ference models of soil used in the software. Basrah site had a settlement value higher than Bagh- dad site due to the soil layers of sand type only. PLAXIS results for sites with minimum bearing capacity showed that for Basrah site the soil went to failure. While, the settlement values for Mosul and Baghdad sites were close to each other due to have nearly same soil layers. Therefore, high rise buildings could not be used in some sites. Also, soil in some locations and under some added loads needed to be improved before the implementation of any constructions.

  • 153.
    Altaie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Materials and the style of buildings used in Iraq during the Islamic period2012Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 69-97Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Islamic period in Iraq lasted 1002 years (637-1639 AD). During this period big cities were constructed and old cities were reconstructed. There was development of the materials used and the design. Bricks, grill wage, plaster, gypsum and marble and stones were used. The environmental conditions were taken in the design of the buildings. The walls were thick and basements and badgur were established. This makes it easier to cool or heat the house. Tar was used to protect the buildings from moisture. New style of buildings was established using new engineering innovations. Well-designed arches and domes were noticed during this period. Islamic buildings had special features such as minarets, arches, domes, vaults, gilding, patterns and decorations.

  • 154.
    Altaie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Progress of building materials and foundation engineering in ancient Iraq2012Inngår i: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, s. 220-241Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Humans realised the importance of housing since the dawn of history. The first man used the caves as shelter. When agricultural activities dominated the life style of humans, villages started to be constructed. Later these were developed into cities. The dawn of civilization started in Iraq. The inhabitants in that time used the available natural materials in their construction. Reviewing the progress of engineering practices of ancient Iraq, reveals the facts that the inhabitants were aware of the principles of construction and engineering. The materials used and the design of the buildings were very suitable from both environmental and engineering perspectives. This work is a critical review of the progress and development of engineering practices and construction materials used in ancient Mesopotamia

  • 155.
    Al-Taie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The need to develop a building code for Iraq2014Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 6, nr 10, s. 610-632Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Building Code is a legal document provided a minimum level of safety and health for the construc-tions to make public living in safe buildings. People recognize the importance of constructing the buildings in safe conditions, since the dawn of civilization. Many countries around the world were facing different kind of disasters such as fires, earthquakes, etc. These disasters made builders to develop methods for safe construction to avoid any disaster. Later, these developments became codes and standards. Since, the middle of the last century many countries established its local codes. This research represents a review of the importance of the codes with a short history for them. Furthermore, reviews for some national codes (Egyptian, Syrian and Arabia Saudi) were done as well as comparison between load’s correction factors, geotechnical requirements and materials used in concrete. Most of the national codes were highly based on the ACI, British and Germany codes and standards. In addition, a review and comparison were presented for International codes (American (ACI) and European (EC)) through a case study. EC code is becoming more common for the world. Eurocode give more flexibility to the user to employ their own standards (national annex). To find the best suitable foundation design to be used in Iraq and the differences when using the American and European codes, a building model was designed and analyzed using STAAD Pro., and SAFE softwares for three locations (Mosul, Baghdad and Basrah). The combination loads used in the two softwares were for ACI and EC codes. Results obtained were very similar. The type of foundation to be chosen for Mosul location is spread or continuous. For Baghdad location the suitable type is raft and for Basrah the choice is raft and piles.In view of the fact that Iraq has no national code engineers and designers were depending on the ACI and British codes and standards. It is very important to have an Iraqi code because it will im-prove the quality and safety of the design and construction of buildings as well as its economic value.

  • 156.
    Altaie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The progress of buildings style and materials from the Ottoman and British occupations of Iraq2012Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 41-51Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The period of ottoman occupation of Iraq was characterized by the same style of buildings and they used local materials as did their predecessors. At the beginning of ottoman occupation, governors were focusing on build mosques and religion schools (Tkaya). Houses were built in random styles depending on the experiences of the builders. For this reason, the houses became irregular and expanded randomly. This lead to the shrinkage of the areas of the roads where they became very narrow and used to referred to as “Drbuna”. At the end of the ottoman period the style of buildings changed and it was reflecting European renaissance influences such as the government campus known as “Qishla”. In 1917 the British army occupied Iraq. During this period the buildings were more inclined to the European style. New materials were used for the first time like cement and iron (Schliemann). The new materials and design destroyed the Iraqi heritage and cultural identity. It is believed that the new housing style did not take into consideration the Iraqi environment.

  • 157.
    Al-Taie, Entidhar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Saaed, Tarek Edrees
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Foundation assessment in different parts of Iraq using STAAD Pro v8i2013Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 7, nr 3, s. 273-281Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Foundation is considered as one of the main parts of any structure such as buildings, railways, bridges, etc. The type of foundation used is highly dependent on the type and properties of soil. The design of foundations requires many factors that should be defined such as the load that the foundation is going to hold, geological conditions of the soil under the foundation, type of soil and the local building code criteria.There are number of differences in the geological and soil conditions in Iraq. As a consequence, these differences are reflected on the type of foundation to be used. Despite these differences, same materials and style of buildings are used all over Iraq. The main problems of Iraqi soil are high gypsum content, salinity and shallow water table depth. These factors that influence the foundations are the soil properties and the amount of loads that transmitted by the superstructure.The situation had been analysed through a case study which illustrated the link between soil and foundation types in three different parts of Iraq (Mosul, Baghdad and Basra). One building was analysed using STAAD. Pro software in these regions. It is evident that Iraqi designers and engineers require local code to define all the loads, materials and design of the foundation to be used. The use of local materials might be very effective from both engineering and economic perspectives.

  • 158.
    Al-Taie, Laith
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Performance of Clay Liners in Near-Surface Repositories in Desert Climate2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Wars in Iraq (1991 and 2003) generated various types of hazardous waste (HW) in the form of soil contaminated by depleted uranium (DU). Other HW emanated from destroyed army vehicles and remnants of Iraqi nuclear facilities holding various types and amounts of chemical and radioactive material. The negative impact of the various wastes on the health conditions of the population was reported from different parts of Iraq, showing an enhanced frequency of cancer and abnormally born infants. For isolating the wastes, which represent low-level and short-lived intermediate level radioactive wastes, near-surface repositories (NSR) are proposed since they represent the least expensive way of solving future problems with sufficient safety. Internationally, the timeframe of the containment of such wastes is designated to be 300 years. Site selection affects and largely controls the selection of a suitable design the aim being to minimize or eliminate migration of hazardous elements from the waste to the environment. The formulation of siting criteria is the first vital step toward the resolution of the problem. Site selection criteria are proposed taking in account three major factors: environmental, geological and socio-economic factors. Accordingly, Iraqi deserts, which make up 60% of Iraq, represent the number one candidate for locating a safe disposal facility, primarily because of the low population, suitable topography, climatic conditions, seismic stability and availability of raw materials. Long-term performance of NSR is directly related to the function of top and bottom liner systems. They should be designed so that they are mutually compatible and combine to effectively isolate the waste. Liners are considered as the main elements of any disposal facility on the ground surface and a properly designed top liner system is of particular importance since it will minimize or eliminate water percolation into the waste body. Compacted clay liners (CCL) should preferably have with a low hydraulic conductivity, which is achievable by proper selection of raw materials, compaction density and construction methods. A further criterion is that they must not soften significantly by expansion on wetting, which puts a limit to the smectite content and density. The liners can consist of native material found near the landfill site, and be used after simple processing, primarily drying and crushing, or be mixed with fillers like silty sand. Since the hydraulic conductivity is the key property of a reliable CCL, relevant experimental determination of the hydraulic conductivity is vital. The common practice in geotechnical laboratories is to apply high hydraulic gradients for getting results quickly but this can lead to non-conservative, incorrect results. The present study involved determination of the hydraulic conductivity of a smectite-rich clay sampled at places within reasonable distance from potential NSR sites. Various hydraulic gradients were applied to samples compacted to several different densities, using two permeants and two filter types. It was concluded that the outflow filter can significantly affect the evaluated conductivity especially when applying high hydraulic gradients. This was partly explained by clogging of outflow filters of conventional fine-porous type by torn-off clay particles at such gradients. A major conclusion was that the gradient in laboratory testing should not exceed 100 m/m.In order to assess the suitability of available raw materials within the Iraqi Deserts, two smectitic soils termed as Green and Red clays were investigated for potential use in CCLs. Both clays are fairly rich in smectite, which calls for mixing them with properly graded silt/sand material from the desert for modifying the expandability. The shear strength, swelling pressure, hydraulic conductivity and creep properties were determined and used for defining criteria for selecting suitable clay-sand ratios. The results showed that 30-50% Green clay mixed with sand and 40-60% Red clay mixed with sand were suitable for constructing top liners with a hydraulic conductivity of 1×10-9 - 1×10-10 m/s. For bottom liners, 70% Green clay mixed with sand and 80% Red clay mixed with sand would be suitable; they were found to have a hydraulic conductivity of 1×10-11 m/s.The long-term performance of CCL is controlled by a number of processes like long periods of extreme dryness and short periods of very heavy rain. The percolation of water through the top liner system of a number of design alternatives were simulated using the code HELP 3.95D and subsequently by the FE program VADOSE/W. For the assumed NSR concept the slope stability of the top liner is essential and it was determined by using FE technique considering various slope angles. The engineering properties, primarily the hydraulic conductivity, swelling pressure and shear strength of 30-50% Green clay mixed with sand were introduced in the simulations. Two initial water contents of the compacted materials were considered representing 1) optimum water content (“wet case”), and 2) air‐dry conditions (“dry case”). Application of the HELP code decided the selection of suitable CCL having a thickness of 0.5 m and inclined by 5.7ᵒ. More detailed analyses with VADOSE/W showed that a mixture at the dry case would bring 0.5 mm (0.5 litre of leaking water per square meter) through CCL in an eight year simulation period. Long-term simulations (up to 300 years) showed that CCL would undergo continuous drying without reaching saturation even in the case of periods of very heavy rain (616 mm) for the wet and dry cases. The slope stability factor for the rather steep angle 30ᵒ was found to be 1.5 for the most critical case representing complete water saturation. In conclusion, the proposed materials and design features are believed to be suitable for practical application.

  • 159.
    Al-Taie, Laith
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Performance of landfills of hazardous waste with special respect to the function of clay liners2012Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This licentiate thesis is based on four papers related to the performance of near-surface low-level (LLW) repositories (landfills) focusing on construction and performance of clay liners in the cappings. The first paper discusses the source of hazardous wastes, their location and their impact on public health. The paper also discusses the scientific basis of the selection of the isolation of such wastes taking in account also cost issues. The paper also shows rules and principles of composing and constructing isolation of such waste according to American and German regulations. The second paper deals with the criteria for locating plants for processing and disposal of hazardous waste in Iraq with special respect to environmental, geological and socio-economic factors. Referring to these criteria a potential disposal site in the Al-Jezira desert is assessed in the paper. The third paper describes the properties of two candidate Iraqi smectitic clays of potential value for isolating hazardous wastes. These clays have been and are still being examined in order to determine their performance and usability for waste isolation. The fourth paper, finally, discusses in detail the hydration-dehydration processes in clay liners in cappings of waste landfills in desertic climates. It also deals with construction issues.

  • 160.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    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.
    Hazardous wastes problems in Iraq: a suggestion for an environmental solution2011Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Iraq passed through many destructive wars where the country infrastructures have been destroyed. Consequently, various types of hazardous wastes generated from 1991 and 2003 wars are exposed in different parts of Iraq without any aspect of human and environment considerations. Contaminants are found in the form of contaminated rubble with depleted uranium (DU). Landfill disposal is still an economical and vital solution that should serve between 500-1000 years for confining hazardous wastes like DU. The longevity of a hazardous waste landfill is mainly controlled by clay based liners. There are many factors affecting the performance of clay liners. These factors were discussed in this research. The main requirements of hazardous waste landfills were listed according to USEPA and German regulations. Finally, the main aspects of landfill siting criteria in Iraq were suggested.

  • 161.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    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.
    Hazardous wastes problems in Iraq:a suggestion for an environmental solution2013Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 3, s. 81-91Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Iraq passed through many destructive wars where the country infrastructures have been destroyed. Consequently, various types of hazardous wastes generated from 1991 and 2003 wars are exposed in different parts of Iraq without any aspect of human and environment considerations. Contaminants are found in the form of contaminated rubble with depleted uranium (DU). Landfill disposal is still an economical and vital solution that should serve between 300-1000 years for confining hazardous wastes like DU. The longevity of a hazardous waste landfill is mainly controlled by clay based liners. There are many factors affecting the performance of clay liners. These factors were discussed. The main requirements of hazardous waste landfills were listed according to USEPA and German regulations. Finally, the main aspects of landfill siting criteria in Iraq were suggested.

  • 162.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Proposed site selection criteria for hazardous waste disposal facilities in Iraq2012Inngår i: Waste Management and the Environment VI / [ed] V. Popov; H. Itoh; C.A. Brebbia, WIT Press, 2012, s. 309-319Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Hazardous wastes in Iraq can be considered as a looming crisis due to its severe impact on health and environment after the 1991 and 2003 wars. The most dangerous type is depleted uranium waste. It is classified by EU and USEPA as Low-Level radioactive Waste and a simple and sufficiently safe way of isolating it from the biosphere is to turn it into a landfill confined within tight dikes. Selection of a disposal site requires a number of conditions to be fulfilled, like socio/economic, environmental and geotechnical criteria, which, in combination, determine where such landfills can be located. This is particularly obvious for Iraq, with its large desertic areas that are available for constructing landfills of hazardous waste. The climatic conditions are suitable and the deep groundwater level valuable for minimizing or avoiding contamination of the area. Heavy rain may occasionally fall requiring special measures to be taken for maintaining stability and tightness. This paper lists suitable site selection criteria for landfills of hazardous waste with special respect to Iraq. An example of a suitable disposal site is described and assessed.

  • 163.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Natural smectitic soils for protective liners in arid climate2014Inngår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 102, s. 104-112Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Compacted clay liners (CCL) can be used to isolate hazardous wastes like the soil and military scrap contaminated with depleted uranium that emanated from the Iraqi wars in 1991 and 2003. Near-surface repositories for such dangerous waste can preferably be located in the Iraqi deserts, which make up 60% of the territory of Iraq. CCLs are usually constructed using a mixture of clayey soil and coarse material compacted in air-dry form or suitably wetted. In the present study, two smectitic soils from Iraq, termed Green and Red clays, were investigated for potential use in CCLs. The shear strength, swelling pressure, hydraulic conductivity and creep properties were determined and used for preliminary design of top and bottom liners. The engineering properties were determined for various dry densities and water contents ranging from air-dry to fully saturated conditions. The results showed that mixtures of sand and 30-50% Green clay, and mixtures of sand and 40-60% Red clay are suitable for constructing top liners with a hydraulic conductivity between 1×10-10 - 1×10-9 m/s. For bottom liners, mixtures of sand and 70% Green clay and mixtures of sand and 80% Red clay can be considered. They were found to have a hydraulic conductivity of 1×10-11 m/s for a density at saturation of 2.1 g/cm3 (dry density 1.7 g/cm3). As to the slope stability of top liners, the shear strength for different clay percentages was found to guarantee slope stability for 18o inclination under both air-dry and water saturated conditions.

  • 164.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hydraulic properties of smectite clays from Iraq with special respect to landfills of DU-contaminated waste2011Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Landfills of material contaminated by depleted uranium and other low-level radioactive waste must be isolated from the biosphere for a sufficiently long time. This can be effectively made in desert climate by collecting contaminated waste in suitable areas confined by tight embankments and covering them with very tight clay liners protected from desiccation and erosion by suitably composed filters and coarse rock fill. Examples of design principles and construction are described in the paper. The clay liners are made of air-dry expanding clay that can be found in sufficient quantities in Iraq and that provide very good tightness at low cost. The construction technique is well known from various projects.

  • 165.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hydraulic properties of smectite clays from Iraq with special respect to landfills of DU-contaminated waste2013Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 3, s. 109-125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Landfills of material contaminated by depleted uranium and other low-level radioactive waste must be isolated from the biosphere for a sufficiently long time. This can be effectively made in desert climate by collecting contaminated waste in suitable areas confined by tight embankments and covering them with very tight clay liners protected from desiccation and erosion by suitably composed filters and coarse rock fill. Examples of design principles and construction are described in the paper. The clay liners are made of air-dry expanding clay that can be found in sufficient quantities in Iraq and that provide very good tightness at low cost. The construction technique is well known from various projects.

  • 166.
    Al-Taie, Laith
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hydraulic properties of smectite rich clay controlled by hydraulic gradients and filter types2014Inngår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 87, s. 73-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The common practice in geotechnical laboratories is to apply high hydraulic gradients for getting results in reasonable time but this can jeopardize the accuracy. In this paper, the hydraulic conductivity of a smectite rich clay from Iraq was determined under different hydraulic gradients (5 to 10000 m/m) using several densities and two permeants. Also, two types of filters were used, ordinary stainless steel sintered filter and sand/silt filter, in order to examine the possible effect of clogging by dragged clay gel particles. It was concluded that the outflow filter can affect the evaluated conductivity especially when applying high hydraulic gradients. For sintered filters the hydraulic conductivity was reduced as the gradient increased, while the conductivity increased as the hydraulic gradient increased when using sand/silt filters. For salt water the impact of the gradient was less obvious than for distilled water. A theoretical model was derived for selecting safe hydraulic gradients as a function of dry density, hydraulic gradient, swelling pressure and permeant type. A major conclusion was that the gradient in laboratory testing should not exceed 100 m/m.

  • 167.
    Alzeyadi, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Rawabdeh, Abdulla M.
    Department of Earth and Environmental Science, Yarmouk University, Irbid, Jordan.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    A Novel Coating Method for Create Filter Media Capable to Remove Phosphate from Wastewater Effectively2019Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 8, s. 443-463Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Filtration materials coating with metallic oxides represented a good method for phosphate sorption. However, most of the researchers utilize chemicals as a source of metallic oxides and heating process to set the chemicals over the filtration materials. This study is aimed to introduce the furnace bottom ash FBA as a source of metallic oxides; it is available free because it is dumped as a waste material from power generation plants. The method of creating new filter media involves coating the limestone and sand by FBA, and the ordinary Portland cement OPC utilized as binder to binding the mixture materials. The water is the factor which is responsible for activating the OPC. All factors such as mixed materials ratio, water content and age of reaction have subjected to optimization process. The results revealed that the optimal mixture for phosphate removal consists of 40% FBA, 5% OPC from dry weight of supporting material, 35% water ratio from the total weight of FBA and OPC, and 14 days are enough to complete the materials reaction. Limestone-furnace bottom ash LFBA indicated high capacity for phosphate sorption and possibility  of  efficiency  regenerate.  This  study  demonstrates  a  new  method  for coating the filtration materials more convenient with sustainability approach.

  • 168.
    Al-Zubaidi, Ibrahim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Numerisk simulering av sättningar och portryck för en provbank på sulfidjord2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Den finkorniga sulfidjorden som finns längs Norrlandskusten är känd för sin stora sättningsbenägenhet och utgör en potentiell miljörisk genom försurning och urlakning av metaller om den inte hanteras rätt. För att förebygga miljörisker och utveckla jordförstärknings- och grundläggningsmetoder måste en ökad kunskap om sulfidjordar tas fram. I ett pågående forskningsprojekt vid Statens Geotekniska Institut studeras sulfidjords kompressionsegenskaper och rekommendationer ska tas fram avseende underlag för sättningsberäkningar. I projektet omfattas ett antal provbankar där ett av dessa områden, Lampen ligger i Kalix i norra Sverige. I detta examensarbete har det utförts numeriska analyser i finita elementprogrammet PLAXIS 2D av sättningar och portryck under en av provbankarna i Lampen och jämförelser görs med tidigare rapporterade fältmätningar.

    Tre olika delar analyseras i FE-programmet PLAXIS 2D. I den första delen, som är huvuddelen, utvärderas materialmodellernas, Soft Soil (SS) respektive Soft Soil Creep (SSC), förmåga att simulera de uppmätta sättningarna och porövertrycken för en period av cirka ett års belastning av provbank. Den andra delen består av en analys av de två deformationstillstånden, axialsymmetriskt och plant. De två deformationstillståden jämförs med hänsyn till sättningar och portryck. I den tredje delen utvärderas påverkan på simulerade resultat av olika nivåer på grundvattenytan, en variation som har observerats i provområdet i Lampen.

    Vid en jämförelse av de konstitutiva modellerna noteras som förväntat större sättningar vid användning av SSC-modellen i jämförelse med SS-modellen. SSC-modellen visar även ett högre porövertryck. Vid jämförelse med i fält uppmätta värden noteras att de mest överensstämmande sättningarna erhålls från SS-modellen medan portrycksutvecklingen simuleras bättre, men ändå långt från bra, med SSC-modellen (för simulering med dubbelsidig dränering).

    Vid analys av deformationstillstånd (axialsymmetriskt kontra plant) noteras en jämnare fördelning av deformationer längs banken vid användandet av axialsymmetriskt tillstånd. Den potentiella brottrörelsen som uppvisas vid släntkrön vid tillämpning av plant deformationstillstånd är inte lika tydlig vid axialsymmetriskt tillstånd. Det axialsymmetriska tillståndet visar även ett lägre porövertryck.

    Numeriska simuleringar av den varierande nivån på grundvattenytan som observerats i fältmätningar visar vid fallet en lägre antagen grundvattennivå en marginellt mindre sättning.  Potentiella brottrörelser blir inte lika tydliga då den lägre nivån på grundvattenytan simuleras.

  • 169.
    Al-Zubaydi, Jaffar
    et al.
    Applied Geology Department, College of Science, University of Babylon.
    Alabidi, Abdulkadhim
    Department of Geology, Faculty of Science, University of Kufa.
    Al-Janabi, Ali
    Applied Geology Department, College of Science, University of Babylon.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Engineering and Tectonic Study of Rocks Discontinuities in the Proposed Abo-Hederya Quarry Site, Missan SE Iraq2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 8, s. 525-534Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A detailed field survey of discontinuity (fractures) was carried out in the proposed Abo-Hederya Quarry Site, 70 km east Missan city, south-east of Iraq, where Al-Mukdadiya Formation (Upper Miocene-Pliocene) is exposed. The discontinuity survey was carried out in 10 stations covering the study area. At each station notes were collected about beds (lithology, thickness and orientation) and discontinuities (orientation, density, spacing, persistence and aperture). The slope stability analysis suggests that there is no real hazard area that could affect the quarry in future. Tectonic analysis demonstrates that tension fractures are common in the study area, while shear fractures (okl, hko, hol and hkl) are the less. The maximum principal stress direction in the study area is N (15 - 40) E, which is compatible with the regional tectonic stress in the area.

  • 170.
    Al-Zuheri, Atiya
    et al.
    Ministry of Science and Technology, Baghdad, Iraq.
    Rashad, Haider
    Ministry of Science and Technology, Baghdad, Iraq.
    Al-Maliki, Ali A.
    Ministry of Science and Technology, Baghdad, Iraq.
    Hussain, Hassain M.
    Remote Sensing Center, University of Kufa, Najaf, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Determination of the chemical Structure of the Iraqi Oil Shale and its hydrocarbon Forms2018Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 10, nr 1, s. 7-20Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The global impact of shale oil has revolutionized the world’s energy markets, resulting in significantly lower oil prices, higher global gross domestic product, changing geopolitics and shifted business models for oil and gas companies. Further and developed research initiative is required to fill critical gaps in knowledge at the interface of shale oil development along with environmental protection, so countries can prepare better for its energy future. This paper explores the characterization of Iraqi originated oil shale using various analytical techniques, such as mass spectrometry (MS), infrared spectroscopy (IR), and Gas Chromatography Mass Spectrography (GC/MS). Based upon analytical results, it is found that the majority of chemical structure is in aliphatic hydrocarbon forms.

  • 171.
    Ameen, Ameen Mohammed Salih
    et al.
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Ibrahim, Zainah
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Othman, Faridah
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Minimizing the Principle Stresses of Powerhoused Rock-Fill Dams Using Control Turbine Running Units: Application of Finite Element Method2018Inngår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, nr 9, artikkel-id 1138Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study focuses on improving the safety of embankment dams by considering theeffects of vibration due to powerhouse operation on the dam body. The study contains two ainparts. In the first part, ANSYS-CFX is used to create the three-dimensional (3D) Finite Volume (FV)model of one vertical Francis turbine unit. The 3D model is run by considering various reservoirconditions and the dimensions of units. The Re-Normalization Group (RNG) k-𝜀𝜀 turbulence modelis employed, and the physical properties of water and the flow haracteristics are defined in theturbine model. In the second phases, a 3D finite element (FE) numerical model for a rock-fill dam iscreated by using ANSYS®, considering the dam connection with its powerhouse represented by fourvertical Francis turbines, foundation, and the upstream reservoir. Changing the upstream watertable minimum and maximum water levels, standers earth gravity, fluid-solid interface, hydrostaticpressure, and the soil properties are onsidered. The dam model runs to cover all possibilities forturbines operating in accordance with the reservoir discharge ranges. In order to minimize stressesin the dam body and increase dam safety, this study optimizes the turbine operating system byintegrating turbine and dam models.

  • 172.
    Andersson, Mattias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kompressionsegenskaper hos sulfidjordar: En fält- och laboratoriestudie av provbankar2012Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In this licentiate thesis is presented the work and the results of the construction of two testembankments on sulphide soils at the test field in Lampen outside the city of Kalix next to thenew rail road Haparandabanan.The main purpose of the licentiate thesis work was to improve the knowledge of compressionproperties of sulphide soils, with focus on the creep properties. Another aim was to establish atest field with extensive instrumented test embankments where settlements and pore pressurescan be measured during many decades.The work with the test embankments has included instrumentation and construction as well asmeasurements of deformations, pore water pressures and soil temperatures. Fieldinvestigations of the properties of the sulphide soil have been performed mainly by CPTsounding,field vane test and Swedish piston sampling. An extensive program of laboratorytests, mainly through oedometer tests, both incremental loading and constant rate of strain,permeability tests and undrained direct simple shear tests, was conducted for thedetermination of compression and strength properties. In this work a literature review wasperformed with the subject sulphide soils and focusing on compression properties. A firstsimple one-dimensional calculation of the total settlements of the test embankments wascarried out regarding the magnitude and the time dependency.The instrumentation and the construction of the test embankments have been carefullyplanned and were carried out as planned. The different measuring equipment as settlementhoses, bellow hoses, settlement gauges and inclinometers, which are installed in theembankments and the underlying sulphide soil to measure deformations in the soil, overallhas given the expected values and the behaviour can be explained by theories of soilmechanics. The pore pressure responses in the underlying sulphide soil are related to theapplied load caused by the mass of the embankments and the effective stresses in the soil. Theresults of the pore pressure measurements are comparable with previous experiences of thebehaviour of load testing on fine-grained soils.Many oedometer tests, incremental loading and constant rate of strain (CRS), have beenperformed to study the compression properties of the sulphide soil and to evaluate differentparameters. It has been possible to identify and evaluate the preconsolidation pressure fromall the CRS oedometer tests, which indicates a good quality of the soil samples, .i.e. a wellperformed piston sampling and following handling of the soil samples. In comparisonbetween the two different oedometer tests, incremental loading and constant rate of strain, thefirst one gave a slightly higher value of evaluated preconsolidation pressure.From the incremental loading tests the creep parameters, , and , were evaluated andthey indicate that the values of these parameters in the sulphide soil from Lampen are slightlyhigher than the previous experiences of sulphide soils have shown. This implies that it can berelatively large differences in creep properties between different sites with sulphide soils andthat incremental loading tests should be performed in the cases when creep settlements are ofinterestThe total calculated settlements of the two embankments in Lampen after 50 years arebetween 1.12 and 1.35 m, with the heights 1.5 m and 2.0 m respectively of the embankments The performed measurements of the settlements showed at the time for the latestmeasurements, i.e. 420 days after the start of the construction of the embankments, that thelargest measured settlements of the ground surface were between 0.34 and 0.38 m. Incomparison with the calculated results, these values were slightly higher, since thecalculations for the same time give settlements in the order of 0.26 to 0.30 m.In this work an extensive experimental basis for the future has been created for compressionproperties including creep properties of the investigated types of sulphide soils, withapplications to settlement calculations of embankments.

  • 173.
    Andersson, Mattias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rogbeck, Yvonne
    SGI.
    Westerberg, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Djupstabilisering i sulfidjord längs Botniabanan2009Inngår i: Samhällsbyggaren, ISSN 2000-2408, nr 4, s. 48-52Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 174.
    Ansal, A.
    et al.
    Kandilli Observatory and Earthquake Research Institute, Bogazici University, Istanbul.
    Erdik, M.
    Kandilli Observatory and Earthquake Research Institute, Bogazici University, Istanbul.
    Studer, J.
    Studer Engineering, Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, Zurich.
    Buchheister, J.
    Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, Zurich.
    Giardini, D.
    Institute of Geophysics, Swiss Federal Institute of Technology, Zurich.
    Fäh, D.
    Institute of Geophysics, Swiss Federal Institute of Technology, Zurich.
    Köksal, D.
    World Institute for Disaster Risk Management- DRM, Virginia.
    Seismic microzonation for earthquake risk mitigation in turkey2004Konferansepaper (Fagfellevurdert)
    Abstract [en]

    As a tool to improve the state of land use management in Turkey and to better mitigate earthquake risk inthe future, a microzonation project was initiated after the 1999 Kocaeli earthquake. The project had twocomponents (a) drafting a microzonation manual [1], (b) conducting pilot case studies in the selected tworegions affected by the 1999 Marmara earthquakes [2]. The main purpose of the study was to test anddemonstrate the applicability of the methodology proposed in the Seismic Microzonation Manual preparedfor the project. The major contributions of the study are the probabilistic assessment of the regionalearthquake hazard, interpretation of the microtremor records, and interpretation of the available geologicaland geotechnical data based on a grid approach. All the available data was transformed to GIS format andthe results are evaluated to obtain a microzonation with respect to site amplification, liquefactionsusceptibility and landslide hazard. An attempt will be made to summarize the results of the pilot studyconducted for the Gölcük region to give an overview of the proposed methodology.

  • 175.
    Ansal, A.
    et al.
    Kandilli Observatory and Earthquake Research Institute, Bogazici University, Istanbul.
    Laue, Jan
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Buchheister, J.
    ETH Zurich.
    Erdik, M.
    Kandilli Observatory and Earthquake Research Institute, Bogazici University, Istanbul.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Studer, J.
    Studer Engineering, Zurich.
    Köksal, D.
    World Institute for Disaster Risk Management- DRM, Virginia.
    Site Characterization and Site Amplification for a Seismic Microzonation Study in Turkey2004Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The pilot areas were divided into cells by a grid system of 500 m x 500 m for estimating the effects of site conditions at a scale of 1:5000 by assigning representative soil profiles at the centre of each grid. These soil profiles were classified according to the Turkish Earthquake Code, NEHRP site classification, equivalent shear wave velocity and used for site response analyses. The zonation maps involve the division of the area into three zones as (A, B, and C). In all cases, the variations of the calculated parameters are considered separately and their frequency distributions were determined. Thus the zone A shows the most unsuitable 33 percentile, zone B the medium 34 percentile and zone C shows the most favorable 33 percentile. A suitable pa-rameter is considered to be the average spectral acceleration between 0.5-1.5 sec periods obtained from site response analysis. Even though more empirical, the spectral amplifi-cations calculated using equivalent shear wave velocities gave consistent values that appear to be realistic when compared with the selected soil profiles. Thus microzonation maps with respect to ground shaking were based on the average of spectral accelerations and spectral amplifications obtained from equivalent shear wave velocities.

  • 176.
    Arnold, André
    et al.
    Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Eidgenossische Technische Hochschule Zurich.
    Influence of unloaded walls on the stress distribution under a raft foundation2009Inngår i: Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering, 2009, Vol. 2, s. 1124-1127Konferansepaper (Fagfellevurdert)
    Abstract [en]

    For the calculation of flexible rafts, the rising structure is often not taken into account on the design with the exception of the load transfer location. Mostly, a uniform stress distribution is assumed below a footing, even though this is only valid if the footing is totally flexible and is able to follow the movement of the soil at every point. The assumption of flexibility is dependent on load and stiffness of the footing while already both, the flexible raft made of concrete as well as the structure itself are influencing the stiffness of a raft. Local stiffening of the foundation, e.g. by locally increased thickness of the raft or flexural rigid connected walls, is not taken into account in the design approach. In this contribution centrifuge model tests are carried out for different raft systems to explore the development of the stress distribution under a flexible raft foundation. Focus is given to identify the influence of the stiffening effects of outside walls for structures mostly loaded via middle columns. © 2009 IOS Press.

  • 177.
    Arnold, André
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zürich.
    Loading behaviour of flexible reaft foundations in ull scale tests and centrifuge models2013Inngår i: / [ed] Delage et al, 2013, s. 879-882Konferansepaper (Fagfellevurdert)
  • 178.
    Arnold, André
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Physical modelling and full scale measurements on soil-structure interaction of flexible raft foundations2010Konferansepaper (Fagfellevurdert)
  • 179.
    Arnold, André
    et al.
    Institute for Geotechnical Engineering, ETH Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, ETH Zurich.
    Espinosa, T.
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Centrifuge modelling of the behaviour of flexible raft foundations on clay and sand2010Inngår i: Physical Modelling in Geotechnics: Proceedings of the 7th International Conference on Physical Modelling in Geotechnics 2010, ICPMG 2010, 2010, Vol. 1, s. 679-684Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In recent decades, foundations used for housing constructions changed from strip foundations to flexible rafts including the whole ground floor. Strip foundations were usually calculated with the assumption of an even stress distribution, and this is often applied to modern flexible raft foundations. The result of these calculations does not represent reality and may often lead to inappropriate design and unexpected structural damage. Physical model tests have been carried out to study the stress distribution on different foundation types on a variety of soils, and under various loading scenarios. A better understanding of the stress distribution between foundation and soil is possible due to normal stress measurements at the interface. For working loads, a clear difference in stress transfer between foundation and clay and sand soils could be observed while a change in depth of soil or shallow inclined bedrock has less effect on the stress distribution at the interface. © 2010 Taylor & Francis Group, London.

  • 180.
    Askarinejad, Amin
    et al.
    Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, ETH Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Swiss Federal Institute of Technology, ETH Zurich.
    Effect of bedrock shape and drainage properties on the stability of slopes2014Inngår i: Physical Modelling in Geotechnics - Proceedings of the 8th International Conference on Physical Modelling in Geotechnics 2014, ICPMG 2014, 2014, Vol. 2, s. 1211-1217Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rainfall induced slope failures were investigated in a series of centrifuge tests on slopes underlain by different bedrock profiles. These tests were designed to interpret observations made during two full scale landslide triggering experiments, focusing on the effect of hydro-mechanical interactions between a soil layer and bedrock during rainfall events. A climate chamber was designed and constructed for the ETH Zurich geotechnical drum centrifuge (Springman et al. 2001). Two different bedrock profiles were tested. The bedrock was parallel to the slope surface as the benchmark, whereas a convex form was placed at the toe of the slope in the alternative, which has potential to act as a supporting buttress. The changes in the pore pressures at the interface of the soil and bedrock were measured. Moreover, the surface movements were monitored by means of cameras installed in the climate chamber. The hydraulic and mechanical responses of the slopes suggested that a convex form of bedrock at the toe might have a "buttressing" effect to the upper parts of the slope due to arching. Moreover, this stabilising effect would be more pronounced if an efficient drainage system was in place behind the buttress to drain locally high pore pressures. © 2014 Taylor & Francis Group.

  • 181.
    Askarinejad, Amin
    et al.
    Institute for Geotechnical Engineering, ETH Zürich.
    Laue, Jan
    Institute for Geotechnical Engineering, ETH Zurich.
    Zweidler, Adrian
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Iten, M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Bleiker, E.
    Institute for Geotechnical Engineering, ETH Zurich.
    Buschor, H.
    Institute for Geotechnical Engineering, ETH Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, ETH Zurich.
    Physical modelling of rainfall induced landslides undercontrolled climatic conditions2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A series of small scale physical modelling tests are performed in a geotechnical drumcentrifuge in order to investigate the triggering mechanisms of landslides due to rainfall. They areconducted under controlled conditions of rainfall intensity and duration, ambient relative humidity, wind,and temperature. These tests have been designed to study the possible failure mechanisms proposed for afull scale landslide experiment. Accordingly, different shapes and hydraulic properties of the bedrock, interms of drainage and exfiltration, are provided for the model. A three dimensional close rangephotogrammetric technique is used to track the movements and monitor the volumetric changes of theground during the cycles of wetting and drying. The slope elevation is filmed during and following therainfall events using a high speed camera and the deformation vectors and strains are elaborated using thePIV method. Details of the design of the climate chamber are discussed in this paper.

  • 182.
    Auchar, Muhammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical modelling for stability of tailings dams2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    A tailings dam is a large embankment structure that is constructed to store the waste from the mining industry. Stability problems may occur in a tailings dam due to factors such as quick rate of raising, internal erosion and liquefaction. The failure of a tailings dam may cause loss of human life and environmental degradation. Tailings Dams must not only be stable during the time the tailings storage facility is in operation, but also long time after the mine is closed. In Sweden, the licensing authorities demand that the tailings dams should be stable up to the next glaciation age, which is interpreted to be 1000 years or more. This goal requires extensive knowledge in order to be able to design the tailings dams so that they can be stable for such a long time. At the Division of Mining and Geotechnical Engineering at Luleå University of Technology, research has been conducted on the stability of tailings dams, using the finite element method which is considered to be suitable for modelling the complex geometry and the material properties of tailings dams. A case study is presented which describes the application of the finite element method in evaluating the stability of a tailings dam.

  • 183.
    Auchar Zardari, Muhammad
    et al.
    Quaid-e-Awam University of Engineering Science and Technology: Nawabshah, Pakistan.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khalid, Muhammad S.
    Department of Urban Management, Kyoto University, Kyoto, Japan.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lund, Björn
    Department of Earth Sciences, Uppsala University, Uppsala, Sweden.
    Numerical Analyses of Earthquake Induced Liquefaction and Deformation Behaviour of an Upstream Tailings Dam2017Inngår i: Advances in Materials Science and Engineering, ISSN 1687-8434, E-ISSN 1687-8442, Vol. 2017, artikkel-id 5389308Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Much of the seismic activity of northern Sweden consists of micro-earthquakes occurring near postglacial faults. However, larger magnitude earthquakes do occur in Sweden, and earthquake statistics indicate that a magnitude 5 event is likely to occur once every century. This paper presents dynamic analyses of the effects of larger earthquakes on an upstream tailings dam at the Aitik copper mine in northern Sweden. The analyses were performed to evaluate the potential for liquefaction and to assess stability of the dam under two specific earthquakes: a commonly occurring magnitude 3.6 event and a more extreme earthquake of magnitude 5.8. The dynamic analyses were carried out with the finite element program PLAXIS using a recently implemented constitutive model called UBCSAND. The results indicate that the magnitude 5.8 earthquake would likely induce liquefaction in a limited zone located below the ground surface near the embankment dikes. It is interpreted that stability of the dam may not be affected due to the limited extent of the liquefied zone. Both types of earthquakes are predicted to induce tolerable magnitudes of displacements. The results of the postseismic slope stability analysis, performed for a state after a seismic event, suggest that the dam is stable during both the earthquakes

  • 184.
    Axelsson, Kennet
    Luleå tekniska universitet.
    Anisotropic work hardening: experiments, theories and finite element application1976Rapport (Annet vitenskapelig)
  • 185.
    Axelsson, Kennet
    Luleå tekniska universitet.
    Constitutive properties and modelling of silty soils1989Inngår i: Proceedings of the twelfth International Conference on Soil Mechanics and Foundation Engineering = Comptes Rendus du Douzième Congrès International de mécanique des Sols et des Travaux de Fondations / Vol. 1, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1989, s. 687-690Konferansepaper (Fagfellevurdert)
    Abstract [en]

    brief description of the characteristics of silty soils is presented. Results are given from undrained triaxial tests on Swedish silts, which show contractant behaviour at small strains whereas the behaviour becomes dilatant close to the critical state. The undrained effective stress path then changes direction at the critical state line which will be followed while the shear strain increases. A simple constitutive model was adopted to predict the transitional behaviour. The model, which is based on the Cam-Clay concept, includes shear hardening in addition to volumetric hardening. Comparisons of predicted and experimental results in the undrained case show a very good agreement, in particular with respect to the transitional behaviour represented by a ``hook'' in the effective stress path.

  • 186.
    Axelsson, Kennet
    Luleå tekniska universitet.
    Kallortsteknikforskning i geoteknik vid University of Alberta och National Research Council of Canada: intryck från studiebesök i januari 19871987Rapport (Annet vitenskapelig)
  • 187.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nyström, B.
    Luleå tekniska universitet.
    Sheng, Daichao
    Luleå tekniska universitet.
    On a finite element model for freezing and thawing soil1989Inngår i: Poac 89: 10th International Conference on Port and Ocean Engineering under Artic Conditions, Luleå, Sweden, 12-16 June 1989 / [ed] Lennart Å. Fransson; Kennet B. Axelsson, Luleå: Högskolan i Luleå , 1989, Vol. 1, s. 342-353Konferansepaper (Fagfellevurdert)
  • 188.
    Axelsson, Kennet
    et al.
    Professor emeritus i byggnadskonstruktion vid Uppsala universitet.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Geoteknik2016Bok (Fagfellevurdert)
    Abstract [sv]

    Geoteknik behandlar jordmaterials mekaniska och tekniska egenskaper, kunskaper som är av betydelse för utförandet av en säker och stabil grundläggning av byggnader och anläggningar. Ämnet stödjer sig på kvartärgeologin, d.v.s. de lösa jordarternas geologi, samt på mekaniken och främst då deformerbara fasta kroppars mekanik. Geoteknik är ett semiempiriskt ämne, d.v.s. provning och erfarenhet ligger också till grund för de metoder som tillämpas.Boken är uppdelad i fyra huvuddelar. I del A ges en introduktion till ämnet samt en återblick på byggnadsgeologin (kvartärgeologin). I del B behandlas jordmaterialläran, d.v.s. jords kemiska och fysikaliska egenskaper vad gäller beståndsdelar, klassificering och strukturell uppbyggnad. Del C behandlar jordmekaniken, d.v.s. mekaniska och hållfasthetstekniska egenskaper hos jord. I del D tillämpas de inhämtade kunskaperna på viktiga geotekniska problemområden såsom bestämning av spännings­tillstånd i jordprofiler, beräkning av byggnaders och anläggningars sättning och geotekniska bärförmåga samt bestämning av jordtryck mot stödkonstruktioner och av jordslänters stabilitet.Geoteknik vänder sig i första hand till studenter på de tekniska hög­s­kolornas program för väg- och vattenbyggnad och samhällsbyggnad samt på högskolornas byggingenjörsprogram.

  • 189.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Runesson, K.
    Chalmers University of Technology.
    Sture, S.
    University of Colorado, Boulder.
    Yu, Y,
    Luleå tekniska universitet.
    Alawji, H.
    University of Colorado, Boulder.
    Characteristics and integration of undrained response of silty soils1989Inngår i: Numerical models in geomechanics: [the proceedings of the 3rd International Symposium on Numerical Models in Geomechanics held on 8 - 11 May 1989, Niagara Falls, Canada / [ed] S. Pietruszczak; Gyanendra Nath Pande, London: Elsevier, 1989, s. 195-203Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Constitutive behaviour of silt is discussed with emphasis on undrained response. Triaxial undrained tests performed on silt shows contractant behaviour at small strains but dilatant behaviour at higher strains, whereafter the soil fails. A constitutive model for silt based on elastoplacticity is proposed and numerically investigated

  • 190.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Rydén, C-G
    Luleå tekniska universitet.
    Experimental determination of pore pressure development in a thawing soil: contribution to the 9th International Conference on Port and Ocean Engineering under Artic Conditions - POAC 871987Rapport (Annet vitenskapelig)
  • 191.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Yu, Yao
    Luleå tekniska universitet.
    Johansson, L.
    Finite element analysis of an excavated slope1992Inngår i: Landslides: proceedings of the international symposium / 10-14 February 1992 / Christchurh / [ed] David H. Bell, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1992, Vol. 6, s. 295-300Konferansepaper (Fagfellevurdert)
  • 192.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Yu, Yao
    Luleå tekniska universitet.
    Runesson, Kenneth
    Chalmers University of Technology.
    Constitutive modelling of Swedish fine grained soils1991Inngår i: Deformation of soils and displacements of structures: X ECSMFE, Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1991, Vol. Vol. 1, s. 183-187Konferansepaper (Fagfellevurdert)
  • 193.
    Axelsson, Kennet
    et al.
    Luleå tekniska universitet.
    Yu, Yao
    Luleå tekniska universitet.
    Runesson, Kenneth
    Chalmers University of Technology, Department of Structural Mechanics.
    Klisinski, M.
    Chalmers University of Technology, Department of Structural Mechanics.
    Determination of constitutive parameters for soils based on optimization1991Inngår i: Computer methods and advances in geomechanics: proceedings of the Seventh International Conference on Computer Methods and Advances in Geomechanics, Cairns, 6-10 May 1991 / [ed] G. Beer, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1991, s. 569-574Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Optimization-based methods for the determination of constitutive parameters of material models are evaluated. Rosenbrock's and Levenberg-Marquardt's algorithms are considered in particular. Based on experimental data for Swedish silt, two plasticity models are calibrated and their performances are compared

  • 194.
    Axelsson, Kenneth
    Luleå tekniska universitet.
    On distortional plastic hardening1978Rapport (Annet vitenskapelig)
  • 195.
    Baby, Sultana Nasrin
    et al.
    Royal Melbourne Institute of Technology, RMIT University, Melbourne, Australia.
    Arrowsmith, Colin
    Royal Melbourne Institute of Technology, RMIT University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of GIS for Mapping Rainwater-Harvesting Potential: Case Study Wollert, Victoria: Application of GIS for Mapping Rainwater-Harvesting Potential: Case Study Wollert, Victoria2019Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 1, s. 14-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Water is a basic normal asset for supporting the condition of life. Accessible water assets are feeling the squeeze because of expanding demand. Soon wa- ter,  which  we  have  epended  upon  to  be  accessible  and  an  unconditional present of nature will turn into a rare roduct. Protection and conservation of water assets are desperately required. In many parts of Victoria, water supply to communities is limited. Rainwater harvesting systems can provide water ator near the point of demand. The systems can be owner and utility operated and  managed.  Rainwater  collected  using  existing  structures,  i.e.  rooftops, parking lots, playgrounds, parks, ponds, floodplains etc., has few negative en- vironmental impacts compared to other technologies for water resources de- velopment. Rainwater is relatively clean and the quality is usually acceptablefor many purposes with little or even no treatment. The physical and chemi- cal properties of rainwater are usually superior to sources of groundwater that may have been subjected to contamination. The present study was intended to measure the rooftop rainwater harvesting potential using GIS techniques. The GIS examination utilized in this investigation was basically an efficient assess- ment  of  rooftop  water  collecting  in  the  chose  Wollert  which  is  a  suburb  in Melbourne, Victoria. With the use of GIS it was conceivable to appraise the ag- gregate sum of water harvestable at the household level. It is very tedious work to assess the catchments available for rooftop rainwater harvesting. Here the roof surfaces are the catchments and GIS is employed to calculate the area of various  types  of  roofs  and  their  potential  for  planning  for  the  area  under study.  As  a  result  Eucalypt  Estate  Wollert  has  huge  potential  and  can  makeabove 179.11 litres water available per person per day throughout the year.

  • 196.
    Baby, Sultana Nasrin
    et al.
    School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology, RMIT University, Melbourne, Australia.
    Arrowsmith, Colin
    School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology, RMIT University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Abbas, Nahlah
    School of Engineering and Technology, Central Queensland University, Melbourne, Australia.
    Spatial Decision Support System for CoastalZone Management under a ChangingClimate in Victoria, Australia2018Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 10, nr 10, s. 637-642, artikkel-id 87732Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ultimate aim of using spatial  datasets and  spatial  data modelling is  fo- cused on enabling a sustainable environment by bringing the public policies into  practice.  The  consequence  will  be  sustainable  spatially  aware  strategic planning for  all  levels  of  Australian government.  Geographical  Information Systems (GIS) are the platform that can serve this aim provided that model, current process and spatial datasets are fit for purpose. To bring public policy into practice a broad range of knowledge from different disciplines is needed. Most decision making processes are pressured in terms of time and driving forces and also the process is beyond the knowledge of individuals in the var- ious  disciplines.  There  is  a  need  for  immediate  uptake  models  and  tools which are relevant to the target subject that will facilitate this decision making process. This paper focuses on realizing the utility in spatial data and spatial data handling in order to help climate change adaptation programs at local government level. Web-based mapping tools can assist planners prepare for the changing climate conditions in Bass Coast Shire Council. The GIS team has gathered data from various climate research organizations to understand projections of what different climate scenarios might look like over the next 100-year period. From this website demo it is hoped that the user will under- stand  how  the  tool  works,  background  information  on  different  GIS  plat- forms, access to interactive mapping, online geospatial analysis tools, videos, open source resource, sea level tools, modelling, 3D visualization and direct download access to various planning and natural resource data sets relating to environment  management.  Some  results  from  our  elevation  data  analysesthrough these Web map visualization tools are provided.

  • 197.
    Barnes, David L.
    et al.
    University of Alaska, Fairbanks.
    Cosden, Elizabeth
    Fairbanks Environmental Service.
    Johnson, Bryan
    Fairbanks Environmental Service.
    Johnson, Karol
    Fairbanks Environmental Service.
    Stjärnström, Stina
    Luleå tekniska universitet.
    Johansson, Karin
    Luleå tekniska universitet.
    Filler, Dennis M.
    Shannon and Wilson, Inc..
    Operation of soil vapor extraction in cold climates2002Inngår i: Cold regions engineering: cold regions impacts on transportation and infrastructure : proceedings of the eleventh international conference, May 20-22, 2002, Anchorage, Alaska / [ed] Kelly S. Merrill, New York: American Society of Civil Engineers (ASCE), 2002, s. 956-967Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Soil Vapor Extraction has proven to be a viable method for reducing the mass of volatile compounds from soils that have been impacted by contamination. The theory, design and use of SVE systems have been fairly well documented, however the use of SVE systems in cold environments such as Alaska has not been adequately investigated to date. This paper examines the use of SVE systems in cold environments. The affect of low soil temperatures on volatile compound removal by SVE is discussed. Methods used to overcome the impact low temperatures have on the operation and effectiveness of SVE systems are examined in detail. Possible low cost strategies such as barometric pumping during winter months are presented as solutions to reducing SVE operating costs in cold regions

  • 198.
    Benckert, A.
    Luleå tekniska universitet.
    Gruvdammar: Dammsäkerhet och efterbehandling2004Inngår i: Proceedings: NGM 2004. XIV Nordic Geotechnical Meeting, Linköping: Svenska geotekniska föreningen , 2004, s. G 51-Konferansepaper (Annet vitenskapelig)
  • 199.
    Bergliv, Elin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Edeskär, Tommy
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laboratory study on two-dimensional image analysis as a tool to evaluate degradation of granular fill materials2016Inngår i: Proceedings of Nordic Conference on Soil Mechanics and Geotechnical NGM: Reykjavik, Iceland 25th – 28th of May 2016, 2016, s. 461-470Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The shape of granular materials is known to affect strength and stiffness properties of soil and fills. Settlements in coarse fills are often explained by rearrangement within the soil skeleton induced by crushing and rounding of the individual aggregates in the intergranular contact points. These processes are not well investigated since it is difficult to measure changes at an aggregatelevel.Currently few attempts have been made to effectively measure and classify shape of granular soil and fill materials. One of the more promising methodologies is digital image analysis. Even if there are some studies on both two and three dimensional analyses on shape of aggregates, no study has focused on identifying shape changes as function of degradation effects of the fill materials.In this study degradation of ballast material has been studied in standardized micro Deval and Los Angeles tests and analysed by two dimensional image analysis and statistical methods. The results showed it was possible to statistically separate the shape and size of the materials before and after the degradation tests. To identify this difference it is essential to use more than one variable each for size and shape.The conclusion of the study is that two-dimensional image analysis can be used as a tool to measure and quantify shape changes on an aggregate level in order to measure degradation. If further developed, the technique can be useful to study deformation processes, e.g. crushing and rounding of aggregates, in coarse fill materials.

  • 200.
    Berglund, Andreas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Prognos av vägars bärförmåga vid tjällossningen: Användning av "Minnesotamodellen" på en teststräcka i Sverige2010Rapport (Annet vitenskapelig)
    Abstract [en]

    The global trend towards a warmer climate and temperatures near or just above 0 °C during winter months, will most likely be more common in future. One of the consequences of this climate change could, in a worst-case scenario, be freezing and thawing over a significant part of the winter with corresponding road bearing capacity problems. Bearing capacity problems may lead to increased costs to society when heavy traffic is forced to change route or carry less weight. In addition, road maintenance costs will increase. According to pulp industry calculations, this industry sector will face additional costs in the range of 510-590 Million SEK every year due to road bearing capacity problems. In addition to this, the costs related to the rapidly growing bio fuel industry will be added. If a reliable forecast of load-bearing capacity problems and potential load restrictions on roads can be found, it would be cost effective for road administration and society. This research report is a part of a work to find methods to forecast bearing capacity problems on roads. The report gives an idea of the possibility to use the temperature based model used in Minnesota, USA in Sweden. The evaluation is done by comparing falling weight deflectometer (FWD) test results with the results from the temperature based forecast model. Temperatures and FWD data were collected in 1997 on a road approximately 7 km outside Luleå, Sweden. The road structure was from the surface: 0,10 m asphalt, 0,40 m sandy gravel/gravely clayey sand and 3,0 m silty clay overlaying a silty moraine. In the report the FWD concept, as well as the FWD parameters of importance are described. How the temperature data was collected is described. The temperatures were collected at a depth of 0,20 m and 0,12 m below the asphalt layer respectively. FWD data was normalised to a force of 50kN. The radius of the segmented falling plate was 0,12 m and all calculations were carried out in accordance with Swedish guidelines. Based upon the FWD tests, the following parameters were evaluated: i/load carrying index, ii/surface modulus, iii/subgrade modulus and iv/"AREA-parameter". A daily average air temperature was determined based upon the detailed measured temperatures. A comparison was done with an average value calculated solely on the recorded maximum and minimum temperatures. It is shown that the two methods gave similar results when used in the forecast model. A short description of the temperature based forecast model is presented as well as an example of how to use it. The needed reference temperature was in the field test evaluated to -0,65 °C and the thaw-degree day limit before the road starts to thaw was determined to 22,2 °C-days. The evaluated FWD parameters show bearing capacity loss at slightly different days. Load carrying index shows a loss of bearing capacity after March 14. As expected the surface modulus is strongly influenced by the air temperature and shows low values on March 10, April 1. After April 11 it decreases significantly. The subgrade modulus shows less stiffness after March 26 and is not as affected by changing air temperatures as the surface modulus. The AREA parameter is also affected by the oscillations in air temperature, much like the surface modulus. It shows low values on March 10 and April 1. After April 11 it decreases significantly towards the lowest values registered in the study. The temperature based forecast model shows that the limit for the accumulated thaw index is reached on March 10 and on April 22-23. The results from the forecast model based upon the daily average temperatures and based upon daily maximum and minimum temperatures only, shows almost the same dates for bearing capacity reductions. Thus, the more simple method with maximum and minimum temperature values seems to give enough accuracy. When comparing the FWD results: AREA-parameter and subgrade modulus with results from the Minnesota model, the subgrade modulus seems to have the greatest agreement with the forecast model. However, they both seem to show the overall development of low bearing capacity during thaw. The overall conclusion about the temperature based forecast model is that it seems to give fairly good results and work well. It will work better if it can be further calibrated but it has some flaws if the temperature seesaws around 0 °C. The forecast model should, despite this, be able to assist road holders in Sweden as a planning tool, when dealing with bearing capacity problems during thaw.

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