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  • 151.
    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.
    Bearing Capacity Affecting the Design of Shallow Foundation in Various Regions of Iraq Using SAP200 & SAFE softwares2014Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 4, nr 4, s. 35-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bearing pressure is the load per unit area along the foundation bottom. The value of bearing pressure can be obtained from soil exploration. In this research, three sites in Iraq were tested (Mosul at north, Baghdad at middle and Basrah at south) for the best type of foundation to be chosen. Seventy nine samples were taken from twenty three boreholes drilled to a depth ranging from 1to 24m, from various sites for the three sites. Samples were tested for their size; Atterberg limits; direct shear; unconfined compression; consolidation and SPT tests. The results showed that the nature of soil in Mosul was generally were silty clay to clay (in some areas silt or sand) with high to very high plasticity. In Baghdad, it was loam clay, silty clay, and in some areas silt. Its plasticity range was medium to high and non-plastic in few sites. For Basrah, the soil type was clay loam and in many places was sand or silt. The value of plasticity was medium. The average and the worst values of bearing capacity were: 177KN/m2 and 77KN/m2 for Mosul; 125 KN/m2 and 68 KN/m2 for Baghdad; and 84KN/m2 and 24 KN/m2 for Basrah. These values were used in a computer model (SAP2000 and SAFE softwares) to find the best suitable foundation in each site. The model suggests that spread or continuous and raft (if basement is used for building with many floors) are suitable for Mosul. For Baghdad, spread and raft type of foundations are suitable. While, for Basrah, raft foundation type are to be used in some areas where building should be less than three floors and for other areas, deep foundation (piles or pier) can only to be used.

  • 152.
    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.
    Effect of bearing capacity on designing foundations in Iraq using STAAD Pro- v8i2014Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 2014, nr 6, s. 292-303Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most of Iraqi soil is classified as Quaternary deposits, especially in the Mesopotamian plain and tributaries of the River Tigris. Soil varies from north to south of Iraq. These differences in soil af-fected the process to select the suitable type of foundation. This research is to study the effect of bearing capacity on shallow foundations in different regions of Iraq. Seventy nine samples were collected from 23 boreholes at three different locations (Mosul at the North, Baghdad at the middle and Basrah at the south of Iraq). The samples were collected at varying depth between 1 to 24m. They were subjected to the following testes: Atterberg limits, sieve and hydrometers, consolidation, direct shear, unconfined compression and the filed (SPT test). The values of the bearing capacity parameters (ϕ and c) were obtained from the above tests. The results obtained were used in the application of the general equation of the bearing capacity. Then, the model of a building was designed (two floors, with mat foundation type) using STAAD Pro software. The average values of bearing capacity in each region were applied in the program (Mosul= 177KPa, Baghdad= 125KPa and Basrah= 84KPa). In addition, the worst bearing capacity values were also used for the three regions (Mosul = 77KPa, Baghdad= 68 KPa and Basrah= 24KPa). The results obtained from the average and worst bearing capacity indicated that for Mosul, we could use shallow foundation (spread and mat used if there was basement) for different areas and for buildings with many sto-ries. For Baghdad region, shallow foundation was more suitable for building not higher than five stories. Finally, for Basrah region, shallow foundations were an appropriate selection, but for most areas deep foundation was the right choice.

  • 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.
    Effect of Material Used in Concrete Mixture on the Foundation Stresses on Soil2015Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, nr 10, s. 668-675Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sustainable design, green architecture and sustainable construction are new methods for design and construction that are employed for environmental and economic challenges. Clay and bricks proved as sustainable building materials. In this paper, crush brick in the concrete mixture instead of normal coarse aggregate will be used. STAAD Prov8i software was applied for the designed of a hypothetical building in different sites of the three locations in Iraq (Mosul at the north, Baghdad at the center and Basrah at the south). The input model data used in the software were depending on the field and laboratory tests done for twenty three sites in the three locations of Iraq. Concrete properties values were used in the software for concrete mixture with crushed bricks. The results values of base pressure obtained from the software were low for the three locations. The maximum values of base pressure under the foundation for both the average and the minimum bearing capacity values for Mosul region for the normal strength concrete and air-entrained were (94, 84) kPa and (91, 82) kPa respectively, for Baghdad region were (89, 82) kPa and (86, 81) kPa respectively. Finally, for Basrah, the results for the base pressure were (84, 77) kPa and (82, 76) kPa, respectively. The results values of the base pressure were less for all locations compared with the base pressure values obtained from a previous work for the same locations. The use of crushed brick as aggregate in the concrete mixture is economical due to its availability as local material and it is durable materials with low weight.

  • 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.
    Estimation of Settlement under Shallow Foundation for Different Regions in Iraq Using SAFE Software2015Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, nr 7, s. 379-386Artikel i tidskrift (Refereegranskat)
    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.

  • 155.
    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 Element2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 5, s. 257-268Artikel i tidskrift (Refereegranskat)
    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.

  • 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.
    Materials and the style of buildings used in Iraq during the Islamic period2012Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 69-97Artikel i tidskrift (Refereegranskat)
    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.

  • 157.
    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 Iraq2012Ingår i: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, s. 220-241Artikel i tidskrift (Refereegranskat)
    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

  • 158.
    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 Iraq2014Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 6, nr 10, s. 610-632Artikel i tidskrift (Refereegranskat)
    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.

  • 159.
    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 Iraq2012Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 41-51Artikel i tidskrift (Refereegranskat)
    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.

  • 160.
    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 v8i2013Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 7, nr 3, s. 273-281Artikel i tidskrift (Refereegranskat)
    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.

  • 161.
    Al-Taie, Laith
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Performance of Clay Liners in Near-Surface Repositories in Desert Climate2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

  • 162.
    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, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna licentiatavhandling är baserad på fyra artiklar med anknytning till utförande av ytnära deponier för lågaktivt avfall (LLW) med fokus på byggande och funktion hos lerlager i topptäckningen. Den första artikeln behandlar ursprunget till farligt avfall, dess förekomst och inverkan på folkhälsan. Artikeln rör också det vetenskapliga underlaget till val av isoleringen av sådant avfall med hänsyn också till kostnadsfrågor. Regler och principer för uppbyggnad av isolering enligt amerikanska och tyska normer redovisas. Den andra artikeln beskriver hur behandling av avfall sker i anläggningar för avfallsdeponering och innehåller förslag till kriterier för placering av sådan verksamhet i Irak med särskild hänsyn till miljömässiga, geologiska och socio-ekonomiska faktorer. Med dessa kriterier som grund visar artikeln att en anläggning i Al-Jeziraöknen kan vara lämplig för behandling och deponering av farligt avfall. Den tredje artikeln beskriver egenskaperna hos två irakiska smektitiska leror som ses som kandidatmaterial för isolering av farligt avfall i Irak. Dessa leror undersöks fortlöpande för att utvärdera deras användbarhet för ändamålet. Den fjärde artikeln, slutligen, behandlar processerna vid bevätning/uttorkning av lerlager i avfallstäckningar i ökenklimat och frågor som gäller byggande av sådana täckningar.

  • 163.
    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 solution2011Konferensbidrag (Övrigt vetenskapligt)
    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.

  • 164.
    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 solution2013Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 3, s. 81-91Artikel i tidskrift (Refereegranskat)
    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.

  • 165.
    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 Iraq2012Ingår i: Waste Management and the Environment VI / [ed] V. Popov; H. Itoh; C.A. Brebbia, WIT Press, 2012, s. 309-319Konferensbidrag (Refereegranskat)
    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.

  • 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.
    Natural smectitic soils for protective liners in arid climate2014Ingår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 102, s. 104-112Artikel i tidskrift (Refereegranskat)
    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.

  • 167.
    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 waste2011Konferensbidrag (Övrigt vetenskapligt)
    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.

  • 168.
    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 waste2013Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 3, s. 109-125Artikel i tidskrift (Refereegranskat)
    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.

  • 169.
    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 types2014Ingår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 87, s. 73-80Artikel i tidskrift (Refereegranskat)
    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.

  • 170.
    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 Effectively2019Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 8, s. 443-463Artikel i tidskrift (Refereegranskat)
    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.

  • 171.
    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 Iraq2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 8, s. 525-534Artikel i tidskrift (Refereegranskat)
    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.

  • 172.
    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 Forms2018Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 10, nr 1, s. 7-20Artikel i tidskrift (Refereegranskat)
    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.

  • 173.
    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 Method2018Ingår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, nr 9, artikel-id 1138Artikel i tidskrift (Refereegranskat)
    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.

  • 174.
    Andersson, Mattias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kompressionsegenskaper hos sulfidjordar: En fält- och laboratoriestudie av provbankar2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    I denna licentiatuppsats redovisas arbetet med och resultaten av uppbyggnaden av två provbankar på sulfidjord vid nya provfältet i Lampen strax utanför Kalix intill nya Haparandabanan.Huvudsyftet med licentiatarbetet var att förbättra kunskapen om sulfidjordars kompressionsegenskaper med fokus på krypegenskaper. Ett annat syfte var att etablera ett provfält med väl instrumenterade provbankar där sättningar och portryck kan följas upp under många årtionden.Arbetet med själva provbankarna har omfattat instrumentering och byggande samt mätningar av deformationer, porvattentryck och jordtemperaturer. Fältundersökningar av sulfidjordens egenskaper har utförts huvudsakligen genom CPT-sondering, vingförsök och kolvprovtagning. Ett omfattande program med laboratorieförsök innehållande bl.a. stegvisa ödometerförsök, CRS-försök, krypförsök, permeabilitetsförsök och odränerade direkta skjuvförsök, har utförts för bestämning av kompressions- och hållfasthetsegenskaper. I arbetet har ingått en litteraturstudie av sulfidjordar med fokus på kompressionsegenskaper. En första enkel endimensionell beräkning har genomförts av provbankarnas sättningar avseende storlek och tidsförlopp.Instrumenteringen och byggnationen av provbankarna har efter noggranna förberedelser utförts som planerat. De olika mätutrustningarna som horisontalslangar, bälgslangar, markpeglar, skruvpeglar och inklinometrar, vilka är installerade i bankarna och underliggande sulfidjord för att mäta rörelser (deformationer) i jorden, har överlag gett mätvärden som är i förväntad storleksordning och vars beteenden kan förklaras med jordmekaniska teorier. Portrycksresponsen i den underliggande sulfidjorden är kopplad till pålagd last orsakad av bankarna och effektivspänningsförhållandena i fält. Resultaten från portrycksmätningarna är jämförbara med tidigare erfarenheter från belastningsförsök på finkorniga jordar.Ett stort antal CRS-försök och stegvisa ödometerförsök har utförts för att studera kompressionsegenskaper och utvärdera olika parametrar hos sulfidjorden. Det har varit möjligt att utvärdera förkonsolideringstrycket från samtliga CRS-försök, vilket tyder på en bra provkvalitet dvs. en väl utförd kolvprovtagning och efterföljande provhantering. Vid en jämförelse mellan CRS-försöken och stegvisa ödometerförsöken gav de senare ett något högre värde på förkonsolideringstrycket.Från de stegvisa ödometerförsöken har krypparametrarna, ... , och ,... , utvärderats och de visar att för sulfidjorden i Lampen är värdena på dessa parametrar något högre än vad tidigare erfarenheter av sulfidjord har visat. Detta visar att det kan vara relativt stora skillnader i krypegenskaper mellan olika lokaler med sulfidjord och att stegvisa ödometerförsök bör utföras i de fall krypsättningar är av intresse.De totala beräknade sättningarna efter 50 år är för de två provbankarna i Lampen mellan 1,12 - 1,35 m, med bankhöjderna 1,5 m respektive 2,0 m. De utförda uppföljningsmätningarna visade vid det senaste mättillfället, dvs. 420 dygn efter påbörjad uppfyllnad av bankarna, att de största uppmätta sättningarna av den ursprungliga markytan var mellan 0,34 – 0,38 m. I en jämförelse med de beräknade resultaten var dessa något större, då beräkningarna efter samma tidpunkt ger sättningar i storleksordningen 0,26 – 0,30 m. Ett omfattande experimentellt underlag för framtiden har tagits fram avseende kompressionsegenskaper inklusive krypegenskaper hos aktuella typer av sulfidjordar med tillämpning på sättningsberäkningar av bankar.

  • 175.
    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 Botniabanan2009Ingår i: Samhällsbyggaren, ISSN 2000-2408, nr 4, s. 48-52Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 176.
    Andrén, Anna
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Degradation of rock and shotcrete due to ice pressure and frost shattering2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Nedbrytning av berg och sprutbetong på grund av istryck och frostsprängningPå senare år har Banverket märkt en ökning av inrapporterade nedfall av berg och sprutbetong i sina järnvägstunnlar. I och med detta så startades en rad forskningsprojekt kring problemen med vattenläckage och isbildning i tunnlar. Detta projekt "Nedbrytning av berg och sprutbetong på grund av istryck och frostsprängning" är ett av dessa. Syftet med detta licentiatprojekt var att samla erfarenhet och information om hur is bildas samt hur istryck påverkar krosszoner, sprickor och framför allt skiktet mellan berg och sprutbetong. Vidare testas hypotesen från litteraturstudien och resultaten från laborationsförsök redovisas.När vatten fryser till is sker en 9 % volymsutvidgning och denna expansion kan orsaka att ett tryck uppstår mot det omgivande materialet. Det omgivande materialet kommer att utsättas för brott om trycket från isen överstiger materialets draghållfasthet eller vidhäftningshållfasthet i skiktet mellan berg och sprutbetong. Storleken på skadan är bland annat beroende av materialets vattenmättnad. Ett delvis vattenmättat material kan klara sig från brott, trots att dess draghållfasthet är låg, genom att expansionen av isen och omfördelning av porvatten kan ske i de porer som från början var fyllda med luft. Ett helt vattenmättat material ger istället efter för frostsprängningen oberoende av sin draghållfasthet, på grund av att materialet inte har något fritt utrymme som kan ta upp expansionen.Det är inte bara isens volymsutvidgningen som orsakar frostsprängning. Forskning visar att om berg har tillgång till fritt vatten under nedkylningen sker en process som liknar den i jord, där vatten vandrar fram mot frysfronten och bildar islinser. På ett liknande sätt vandrar vatten i berg och orsakar tillväxt av isskikt i exempelvis en por eller spricka, vilket kan orsaka att istrycket ökar. Vattenvandringen sker på grund av att det finns en tunn vattenfilm av adsorberat vatten längs mineralkornens ytor och i denna vattenfilm finns möjlighet för vatten att vandra mot frysfronten. Experimentellt arbete har visat att en betydande del av det adsorberade vattnet förblir ofruset vid negativa temperaturer, inte bara i jord utan även i berg och detta möjliggör vattenvandringen.Vattenvandring och istillväxt är inte bara beroende av tillgången till vatten och frystemperatur, utan även av fryshastighet och varaktighet av köldgrader. Om berg och sprutbetong utsätts för snabb nedkylning minskar vattenfilmens tjocklek och vattenvandringen förhindras, vilket begränsar frostsprängningen av materialet. Om istället berget kyls ned långsamt, tillåts vattenvandringen att ske under en längre period, vilket kan resultera i större frostsprängning. I de utförda fältundersökningarna visade det sig att varaktigheten och förändring av frysperioderna var av stor vikt för tillväxten av isformationer. Om frysperioden hade lång varaktighet frös vissa av sprickorna och läckagepunkterna. Om läckagen istället utsattes för kortare perioder av frysning och tining frös aldrig sprickorna och vatten fortsatte att läcka med växande isformationer som följd. För kalla områden, som i de norra delarna av Sverige, uppstår dessa problem även långt in i tunnlarna. Problemen uppstår på grund av att läckagevatten transporterar fram värme från bergmassan till den kalla tunnelytan. Värmen från läckagevattnet håller bergmassan kring spricköppningen ofrusen trots att tunnelluften är kall. Därför fortsätter sprickan att föra fram vatten med konsekvensen att det bildas is när vattnet väl kommer ut i den kalla tunnelluften. En annan erfarenhet från fältundersökningarna var att utfallen av berg och sprutbetong ofta förekom i sektioner som hade problem med vattenläckage.Resultaten från laborationsförsöken utförda i det här licentiatprojektet visar också att vatten i kombination med negativa temperaturer kan orsaka nedbrytningsproblem. De utförda dragtesterna visade att vidhäftnings-hållfastheten minskar med ungefär 50 % när sprutbetong/bergproverna hade utsatts för frysning. Vidare visade mätningarna av akustisk emission (AE) att fler AE-händelser skedde när sprutbetong/bergproverna hade tillgång till vatten under frysningen. Litteraturstudien, fältundersökningarna i järnvägstunnlarna och laborationsförsöken pekar på att tillgången på vatten under frysning kan orsaka skador på skiktet mellan berg och sprutbetong. Detta bekräftar hypotesen att utfall av berg och sprutbetong kan uppstå på grund av att istryck i en spricka eller i skiktet mellan berg och sprutbetong överskrider draghållfastheten för materialet eller vidhäftningshållfastheten mellan berg och sprutbetong. En sak som laborationsförsöken inte kunde ge ett bra svar på var ifall utfallen kunde ske på grund av spridning av en liten yta som redan från början hade dålig vidhäftning runt en spricköppning. Men försöken visade att det förekom mycket aktivitet under frysningen i de områden som preparerats med dålig vidhäftning. Så det verkar som att små områden med dålig vidhäftning kan påverkar försämringen av vidhäftningen mellan berg och sprutbetong.

  • 177.
    Andrén, Anna
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dahlström, Lars-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Temperaturflöden i järnvägstunnlar – Glödberget2011Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Under vinterhalvåret orsakar is stora problem i flera av Trafikverkets järnvägstunnlar. Vatten som fryser bildar istappar och svallis som kan fall ned i spår samt växa till sådan storlek att de inkräktar på det ”fria rummet” som tågen kräver för att passera genom tunneln. Belysningsarmaturer och kablar bryts sönder på grund av islast och spåren blir isbelagda på grund av takdropp och svallisbildning. Återkommande frysperioder medför att berg och sprutbetong i tak och väggar kan lossna och falla ner. För att upprätthålla säkerheten och förhindra trafikstörningar kräver många tunnlar omfattande underhållsinsatser. För att kunna reducera underhållet i tunnlarna, krävs förbättrad kunskap kring köldinträngning och effekterna av istryck på det bärande huvudsystemet. 2002 utförde Högskolan i Gävle och KTH en modellstudie för att bestämma temperatur-förhållanden i tunnlar. För att verifiera modellstudien genomförs nu mätningar i fält och projektet utförs i ett samarbete mellan Trafikverket och Luleå Tekniska Universitet. Denna Tekniska rapport redovisar de mätningar som hittills utförts i Glödbergstunneln vid Nyåker som ligger 8 mil sydväst om Umeå. Mätningarna visar att framtagna modeller underskattar köldinträngningen. Trots att tunneln är 1680 m lång, sker köldinträngning i hela tunnelns längd även vid några få minusgrader utanför tunneln. En bidragande orsak till att fältmätningarna och modellen inte överensstämmer kan vara att modellstudien bygger på en helt oisolerad tunnel. I Glödbergstunneln finns en stor del frostisolerande dräner uppsatta. De frostisolerande dränernas funktion är att förhindra att inläckande vatten fryser till is, men isoleringen förhindrar inte bara kylan att tränga in till läckaget, den hindrar även bergvärmen från att komma ut i tunneln och värma upp den kalla uteluften. Isoleringen möjliggör för kylan att tränga längre in i tunneln än vad den skulle ha gjort i fall bergvärmen gavs möjlighet att värma upp den kalla uteluften på dess väg in längs tunneln. Mängden frostisolerande dräner och hur stor del av tunnels vägg- och takyta som är inklädd, täckningsgraden, påverkar därmed köldinträngningens längd. Mätningar av temperaturer har utförts ned i ballasten. Glödbergstunneln har en undersprängning på 2 m under RUK, med motiveringen att ledningar för exempelvis dräneringsvatten ska vara förlagda på frostfritt djup. Mätningarna visar att temperaturen inte tränger så långt ned som man tidigare befarat och undersprängning i de mittersta delarna av tunneln hade kunnat göras mindre, med avseende på frostrisken. Temperaturmätningarna bakom en frostisolerad drän i mitten av spårtunneln, har visat att dränen klarar av att jämna ut de temperaturväxlingar som sker i tunnelluften utanför dränen. Men då temperaturen är negativ under en längre period kryper även temperaturen bakom dränen under 0 C och då förhindras dräneringsmöjligheten på grund av isbildning och det kan orsaka frostsprängning av dränen. Mätningar av lufttemperatur i den intilliggande servicetunneln visar tydligt hur köldinträngningen påverkas av luftrörelser. Servicetunneln är stängd med portar mot både ute- och tunnelluft. När luften i en tunnel inte utsätts för rörelse, värms den upp av bergvärmen och antar samma temperatur som berget har. Bergtemperaturen brukar oftast sammanfalla men den årsmedeltemperatur som gäller för den plats där tunneln är belägen. För Glödbergstunneln stämmer detta mycket bra överens med de utförda mätningarna i servicetunneln. Sökord: köldinträngning, istryck, frostsprängning, temperaturmätning, underhåll, järnvägstunnel.

  • 178.
    Andrén, Anna
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dahlström, Lars-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Temperaturflöden i järnvägstunnlar och konsekvenser för drift och underhåll2008Ingår i: Bergmekanikdag: föredrag vid Bergmekanikdag i Stockholm 10 mars 2008, Stiftelsen bergteknisk forskning - Befo , 2008Konferensbidrag (Övrigt vetenskapligt)
  • 179.
    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 turkey2004Konferensbidrag (Refereegranskat)
    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.

  • 180.
    Arasteh khouy, Iman
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nissen, Arne
    Trafikverket.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Optimisation of track geometry inspection interval2014Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 228, nr 5, s. 546-556Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The measurement and improvement of track quality are key issues in determining the time at which railway maintenance must be performed and its cost. Efficient track maintenance ensures optimum allocation of limited maintenance resources which has an enormous effect on maintenance efficiency. Applying an appropriate tamping strategy helps reduce maintenance costs, making operations more cost-effective and leading to increased safety and passenger comfort levels. This paper discusses optimisation of the track geometry inspection interval with a view to minimising the total ballast maintenance costs per unit traffic load. The proposed model considers inspection time, the maintenance-planning horizon time after inspection and takes into account the costs associated with inspection, tamping and risk of accidents due to poor track quality. It draws on track geometry data from the iron ore line (Malmbanan) in northern Sweden, used by both passenger and freight trains, to find the probability distribution of geometry faults.

  • 181.
    Arasteh khouy, Iman
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nissen, Arne
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Evaluation of track geometry maintenance for heavy haul railroad in Sweden: a case study2014Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 228, nr 5, s. 496-503Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The measurement and improvement of track quality are key issues in determining both the restoration time and cost of railway maintenance. Applying the optimal tamping strategy helps reduce maintenance costs, making operations more cost effective and leading to increased safety and passenger comfort. In this paper, track geometry data from the iron ore line (Malmbanan) in northern Sweden, which handles both passenger and freight trains, are used to evaluate track geometry maintenance in cold climate. The paper describes Trafikverket’s (Swedish Transport Administration) tamping strategy and evaluates its effectiveness in measuring, reporting, and improving track quality. Finally, it evaluates the performance of the maintenance contractor and discusses the importance of the functional requirements stated in the outsourcing contracts.

  • 182.
    Arasteh khouy, Iman
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nissen, Arne
    Trafikverket.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Evaluation of track geometry degradation in Swedish heavy haul railroad: a case study2012Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 15, nr 2, s. 11-16Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The measurement and improvement of track quality are key issues in determining both the time and cost of railway maintenance. Efficient track geometry maintenance ensures optimum allocation of limited maintenance resources and has an enormous effect on maintenance efficiency. Applying the appropriate tamping strategy also helps reduce maintenance costs, making operations more cost effective and leading to increased safety and passenger comfort. In this paper, track geometry data from the iron ore line in northern Sweden, which handles both passenger and freight trains, are used to calculate track quality degradation trend in a cold climate. The paper describes Trafikverket’s (Swedish Transport Administration) tamping strategy and illustrates the distribution of safety failures in different seasons. It also analyses the track geometry degradation and discuss about the possible reasons for distribution of failures over a year and along the track.

  • 183.
    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 sand2010Ingår i: Physical Modelling in Geotechnics: Proceedings of the 7th International Conference on Physical Modelling in Geotechnics 2010, ICPMG 2010, 2010, Vol. 1, s. 679-684Konferensbidrag (Refereegranskat)
    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.

  • 184. Arvanitidis, Ioannis
    et al.
    Nyberg, Ulf
    Ouchterlony, Finn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Diameterns inverkan på detonationsegenskaperna hos emulsionssprängämne E682 i cylinderprovet2004Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Cylindertest har genomförts på emulsionssprängämne 682 (E682) i syfte att undersöka hur arbetsförmågan varierar med laddningsdiametern inom intervallet 40-100 mm. Två satser syrebalanserad emulsion undersöktes, ren E682 och E682 med 20% ANFO. Receptet till E682 är framtaget tillsammans med Dyno Nobel och Kimit AB. Denna experiment emulsion har undersökts tidigare, bl.a. finns en brinnmodell. Emulsionen är syrebalanserad. När det gäller den volymbaserade explosionsenergin så ligger ren E682 något lägre än E682 med 20% ANFO, 3.47 MJ/dm3 respektive 3.85 MJ/dm3. Mjukglödgade 1 m långa kopparrör med inner/ytter diametrar 40/44, 60/66, 80/88 och 100/110 (mm/mm) har använts. Försöksuppställningen består av ett vertikalt monterat kopparrör fyllt med E682. Laddningsdensiteten var ca 1130 och 1200 kg/m3 för ren E682 respektive E682 med 20% ANFO. Initieringen sker ovanifrån med sprängdeg varvid detonationsfronten går nedåt genom laddningen i röret. Detonationsfrontens hastighet (VOD) mäts med resistansprob som monterats längs rörets mittlinje. Den radiella expansionen mäts med 10 kontaktpinnar ca 65 cm nedåt på röret ifrån initieringspunkten. Expansionen mäts från 0.5 mm från rörväggen till en total volymexpansion om 6-9ggr. Med hjälp av VOD och expansionsdata kan man räkna fram kopparväggens rörelse och den kinetiska slutenergin kallad "Gurneyenergin" som är ett mått på sprängämnets arbetsförmåga. Genom att jämföra Gurneyenergin med explosionsenergin kan man få fram en verkningsgrad. Gurneyenergin, som mäts i MJ/kg sprängämne, var oberoende av laddningsdiametern. Följden blir att även verkningsgraden är oberoende av laddningsdiametern inom det studerade intervallet 40-100 mm. För ren emulsion låg kopparväggens sluthastighet runt 1280 ± 20 m/s och Gurneyenergin 1.77 ± 0.06 MJ/kg. Vad gäller E682 med 20 % ANFO blev hastigheten något högre, 1290 ± 20 m/s samt Gurneyenergin 1.71 ± 0.07 MJ/kg. Verkningsgraden för ren E682 är 58 ± 3 % och för E682 med 20 % ANFO 53 ± 3% av tillgänglig energi. Den något lägre verkningsgraden för E682 med 20 % ANFO kan förklaras med att ANFO i sig har en lägre verkningsgrad ca 40-50 %. En tidigare försöksserie av Nie (2001) visade förvånansvärt nog verkningsgraden hos försöken med 80/88 rören var markant högre än hos 40/44 och 100/110 rören. I jämförelse med denna studie så verkar sluthastigheterna i Nie's försök med 80/88 rören vara onormalt höga vilket kan tänkas bero på materialfel eller dimensionsfel hos rören. Man kan tydligt se att kopparväggens acceleration ökar med minskande rördiameter. Detta är en naturlig följd av att massan som ska accelereras minskar mycket snabbare med minskande laddningsdiameter än vad detonationstrycket gör. Sammanfattningsvis kan man säga att verkningsgraden minskar något för E682 då man tillsätter ANFO men att den är oberoende av laddningsdiametern. Om man jämför Gurneyenergin på volymbasis så ligger däremot ren E682 obetydligt lägre än E682 med 20% ANFO, ca 2%.

  • 185.
    Ask, D.
    et al.
    Vattenfall Power Consultant AB, Luleå.
    Stephansson, O.
    GeoForschungsZentrum Potsdam.
    Cornet, F.H.
    Institut de Physique du Globe de Strasbourg.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rock stress, rock stress measurements, and the Integrated Stress Determination Method (ISDM)2009Ingår i: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 42, nr 4, s. 559-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The primary objectives of this work are to (1) improve the understanding of the prevailing stress distribution at the Äspö Hard Rock Laboratory (HRL) in SE Sweden by employing an integrated stress determination approach, and in order to accomplish this (2) extend the existing stress integration methodology denominated integrated stress determination method (ISDM; Cornet in Comprehensive Rock Engineering vol 3, Pergamon Press, Oxford, pp 413-432, 1993a). The new developments of the ISDM involve a 12-parameter representation of the regional stress field in the rock mass (i.e., the full stress tensor and its variation with depth) that is applicable to hydraulic stress data (sleeve fracturing, hydraulic fracturing, and hydraulic tests on pre-existing fractures), overcoring data (CSIR- and CSIRO-type of devices), and to combinations of hydraulic and overcoring stress data. For the latter case, the elastic parameters of the overcoring technique may be solved in situ by allowing the hydraulic stress data to constrain them. As a result, the problem then involves 14 model parameters. Results from the study show that the ISDM effectively improves the precision of the prevailing stress field determination and that it is especially powerful for identification of consistencies/inconsistencies in an existing data set. Indeed, this is the very basic premise and goal of stress integration; combine all available data to achieve as complete a characterization of the mechanical stress model as possible, and not to identify a solution that fits only loosely the maximum amount of stress data.

  • 186.
    Ask, Daniel
    et al.
    Vattenfall Power Consultant AB, Luleå.
    Cornet, F.H.
    Institute de Physique du Globe de Strasbourgh.
    Fontbonne, F.
    GEO-energies, Clermont-Ferrand.
    Nilsson, Tommy
    Jönsson, L.
    Hydraulikmontage i Luleå AB.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    A quadruple packer tool for conducting hydraulic stress measurements in mines and other high stress settings2009Ingår i: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 46, nr 6, s. 1097-1102Artikel i tidskrift (Refereegranskat)
  • 187.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Data report: consolidation state and stress ratio of clay-rich sediments from Site U13202009Ingår i: Proceedings of the Integrated Ocean Drilling Program, ISSN 1930-1014, Vol. 308Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Overpressure and fluid flow processes in the deepwater Gulf of Mexico were investigated during Expedition 308 of the Integrated Ocean Drilling Program.This data report presents the results from a reconsolidation test that was carried out on a clay-rich sample from the base of Brazos-Trinity Basin IV, at 276.40 m below seafloor. The sample was subjected to a stress path of uniaxial strain (K0 reconsolidation), and the test was conducted in an advanced triaxial cell under drained conditions. Posttest investigation revealed that the sample was disturbed by drilling. The results should be interpreted with care.The sample was loaded to a total effective vertical stress, σv′, of 24 MPa, corresponding to effective horizontal stress, σh′, of >16 MPa and vertical strain, εv, of 16%. The results propose an effective vertical yield stress of 2.03 MPa, which suggests a maximum pore fluid pressure in excess of hydrostatic water pressure of 0.24 MPa. Furthermore, the ratio between effective horizontal and vertical stresses is rather constant, ~0.7, even at high stress magnitudes.

  • 188.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Technological Drivers for Future IODP Science: Progressing from application-specific to systematic technological development2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Since its inception with the Deep Sea Drilling Project (DSDP) scientific ocean drilling has always had a technology development component. Technology development has been critical for advancing ocean drilling and scientific progress would not have occurred without it. Resolution of the simpler technical problems have progressed satisfactorily through an application-specific process, however the more difficult and complex problems that limit achieving many of the scientific objectives of the Initial Science Plan (ISP) and active IODP drilling proposals remain unresolved and will require a more comprehensive and systematic effort. This White Paper highlights key technological/scientific goals identified by the Engineering Development Panel (EDP)-Improving Core Recovery and Quality; Addressing Geohazards; Microbiology in the Marine Subsurface Environment; Drilling to the Moho and Other Complex Drilling Projects; and Virtual Staffing-that are derived from the EDP Technology Roadmap v. 3.0 (http://www.iodp.org/eng-dev), the ISP, and active drilling proposals; and reinforced by the Science and Technology Panel (STP) Roadmap (v. 0.93). They offer the greatest promise for transforming scientific ocean drilling. In order to accomplish some of these goals, large-scale engineering developments will be necessary to deliver the transformational science needed by any drilling program beyond 2013.

  • 189.
    Ask, Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ask, Daniel
    Vattenfall Power Consultant AB, Luleå.
    Christiansson, R.
    Swedish Nuclear Fuel and Waste Management Co.
    Detection of borehole breakouts at the Forsmark site, Sweden2006Ingår i: In-situ rock stress: measurement, interpretation and application : proceedings of the International Symposium on In-situ Rock Stress, Trondheim, Norway, June 19-21, 2006/ / [ed] Ming Lu, London: Taylor and Francis Group , 2006, s. 79-86Konferensbidrag (Refereegranskat)
    Abstract [en]

    The objective of this paper was to investigate if borehole breakouts exist at the Forsmark investigation site of the Swedish Nuclear Fuel and Waste Management Co. Breakouts generally form when the stress concentration around the borehole exceeds the rock strength of the borehole wall, and result in borehole failure in the direction parallel to the minimum horizontal stress in vertical boreholes. Borehole televiewer and borehole image processing system data in boreholes KFM01A and KFM01B have been analyzed. The analyzes reveal that breakouts appear over 30-40% of the length of the investigated boreholes. The breakouts appear with both shallow- and deep-failure depths, where the overwhelming majority is of the shallow failure type. The scope of this initial study does not include the full characterization of identified breakouts and it is not clear at this stage as to the origin of the breakouts, i.e. if they are stress and/or drilling induced

  • 190.
    Ask, Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kopf, Achim
    DFG Research Center Ocean Margins, University of Bremen.
    Constraints on the state of in situ effective stress and the mechanical behavior of ODP Leg 186 claystones in the Japan Trench forearc2004Ingår i: Island Arc, ISSN 1038-4871, E-ISSN 1440-1738, Vol. 13, nr 1, s. 242-257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Japan Trench forearc offshore Honshu Island in northeast Japan, where the 130-m.y.-old Pacific oceanic plate is presently subducted, was drilled during the Ocean Drilling Program Leg 186. Results from mechanical and sedimentological studies of claystones recovered from Sites 1150 and 1151 in the overlying erosional forearc wedge are reported in the present study. Although many physical properties are similar in the seismic (Site 1150) and aseismic portion (Site 1151) of the shallow forearc, Site 1150 displayed a higher abundance of open fractures, two prominent fault zones and enigmatic pore fluid signatures in the claystones. The abundance of weak mineral phases, together with high smectite contents (from X-ray diffraction), control the low friction coefficients of 0.33–0.39 of the claystones in ring-shear experiments. Results from triaxial testing proposed overall low magnitudes of in situ effective vertical stress, with somewhat lower values at Site 1150 than at Site 1151. Similarly, samples from Site 1150 displayed slightly higher pore fluid pressures than those at Site 1151. The high sediment porosities, which are in part also a result of intact diatom tests (from scanning electron microscope), together with the anomalous fluid signatures and elevated pore fluid pressures, could very likely result from upward migration and influx of deep-seated waters. Dewatering reactions at depth result in enhanced pore fluid pressure transients along out-of-sequence thrusts and consequently lower effective stress. At depths greater than that of Leg 186 drilling, elevated pressure–temperature conditions trigger mineral transformation and cementation, which result in increasing friction, unstable sliding and seismic rupture. Such earthquakes could have repeatedly disaggregated the consolidated claystone fabrics at the seismic site, and could be responsible for differences in yield strength and cementation when compared to the aseismic Site 1151.

  • 191.
    Ask, Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Morgan, Julia
    Rice University.
    Projection of mechanical properties from shallow to greater depths2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Deformation processes in sediments are directly controlled by the state of in situ effective stresses, the mechanical-, physical- and geochemical properties of the materials of the fault zone and surrounding wall rocks, and time. Measurements of these properties are needed for understanding of the process of earthquake generation. The recent drilling expeditions to Nankai Trough, by the Integrated Ocean Drilling Program demonstrate the technical difficulties involved in subduction zone drilling. At present, scientific drilling operations have successfully penetrated the decollement only at shallow depths in the Nankai accretionary prism. These data provide the only present access to future seismogenic zone materials. In the frontal region, the strata are being partitioned into accreting and subducting packages, some of which may ultimately pass into the seismogenic zone. Sediments deposited and locally cemented within the Shikoku Basin are partitioned by the basal decollement and they follow distinctive deformation pathways across the margin. Our hypothesis is that enhanced strength in the underthrust package allows it to carry excess pore fluids deep into the subduction zone, potentially to be released rapidly and seismogenically. The objectives for mechanical testing are to probe the yield and failure surfaces of these sediments, as well as their post-failure deformation behavior. This information is useful for making predictions about sediment response to accretion, underplating, and slip along the decollement. Reconsolidation tests have been carried out on Ocean Drilling Program cores collected from the reference site seaward of the active Nankai decollement zone off the southeast coast of Japan (ODP Site 1173). We have conducted two tests each from two subsamples from within Lower Shikoku Basin, approximately 30 m above, and approximately 85 m below the proto-decollement. This allows documentation of changes in mechanical strength and stress history across the proto-decollement horizon within the same lithostratigraphic unit. The initial porosities for the deeper and shallower samples are 43-44% and 56-57%, respectively. The results suggest that the shallower samples are significantly stiffer than the deeper ones, which is reflected by higher effective yield stress and higher elastic modulus in the shallower samples. The results regarding the elastic-plastic behavior is more challenging to interpret: One sample from above the decollement experienced brittle failure at an effective vertical stress of 8.7 MPa, whereas one sample from below the decollement show evidence on cement destruction and plastic deformation up to the maximum stress of 9.5 MPa. These two stress levels also are the highest effective vertical stress of samples. The results will contribute to our model for the evolution of deformation in sediments in the Nankai accretionary prism They will also allow us to project the mechanical behavior from shallow to greater depths.

  • 192.
    Ask, Maria
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Morgan, Julia K.
    Rice University, Houston.
    Projection of mechanical properties from shallow to greater depths seaward of the Nankai accretionary prism2010Ingår i: Tectonophysics, ISSN 0040-1951, E-ISSN 1879-3266, Vol. 482, nr 1-4, s. 50-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Deformation processes in sediments at accretionary prisms are directly controlled by the state of in situ effective stresses, the mechanical, physical and geochemical properties of the materials of the fault zone and surrounding wall rocks, as well as time. Measurements of these properties and their evolution in space and time, are therefore needed for a full understanding of the process of earthquake generation within subduction zones.Reconsolidation tests have been carried out on Ocean Drilling Program cores collected from a reference site seaward of the active Nankai décollement zone off the southeast coast of Japan. The reconsolidation stress path subjects the samples to uniaxial strain deformation, which mimics their stress history, however at much higher loading rates than in the natural system. We have conducted two tests each from two mudstone samples within Lower Shikoku Basin. The samples were collected at 361 and 476 meter below seafloor, on either side of the protodécollement horizon.The objectives for mechanical testing are to probe the yield and failure surfaces of these shallow sediments (Considering their large scale behavior, our tests show that the samples collected above the protodécollement have higher strength than those below. We propose that cementation, microfabric and mineralogy of the sediments above the protodécollement result in a higher effective yield stress than predicted from in situ effective vertical stress at hydrostatic pore pressures. Sediments below the protodécollement, in contrast, are slightly underconsolidated, and provide an upper constraint on the magnitude of in situ effective vertical stress and pore-fluid pressure. We also used the test results to make initial predictions for the yield surface in 2D and 3D for subdécollement samples across the margin. The construction of the 2D yield surface is the first attempt to quantify the model of sediment deformation proposed by Morgan et al. (2007). These results hint that the presence of cement has a strong, and increasing, influence on sediment behavior. Further testing is needed to verify these findings.

  • 193.
    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 slopes2014Ingår i: Physical Modelling in Geotechnics - Proceedings of the 8th International Conference on Physical Modelling in Geotechnics 2014, ICPMG 2014, 2014, Vol. 2, s. 1211-1217Konferensbidrag (Refereegranskat)
    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.

  • 194.
    Astrand, M.
    et al.
    ABB Corp Res, Control Optimizat & Analyt, Automat Solut, Västerås, KTH Royal Inst Technol.
    Johansson, M.
    KTH Royal Inst Technol.
    Greberg, Jenny
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Underground mine scheduling modelled as a flow shop: a review of relevant work and future challenges2018Ingår i: Journal of the southern African institute of mining and metallurgy, ISSN 2225-6253, Vol. 118, nr 12, s. 1265-1276Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Advanced planning and automation are increasingly important in modern mines. Sophisticated methods for long-term mine planning are often used, and the advent of autonomous machines makes the actual operation more predictable. However, the interface between these two timescales, i.e. the scheduling of the mobile production fleet, often limits the ability to operate mines at maximum profitability. We show how scheduling the production fleet in an underground mine can be modelled as a flow shop. A flow shop is a general abstract process formulation that captures the key properties of a scheduling problem without going into specific details. Thus, the flow shop enables mine scheduling to reap the benefits of scheduling research from other industries. We review recent results from the mining community and the flow shop community, and introduce scheduling methods used in these two fields. This work aims at providing value to researchers from the mining community who want to leverage their skill set, as well as to theoretical researchers by presenting the mining process as a potential application area. Lastly, we discuss the results, and outline some future challenges and opportunities facing the industry.

  • 195.
    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 dams2013Konferensbidrag (Övrigt vetenskapligt)
    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.

  • 196.
    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 Dam2017Ingår i: Advances in Materials Science and Engineering, ISSN 1687-8434, E-ISSN 1687-8442, Vol. 2017, artikel-id 5389308Artikel i tidskrift (Refereegranskat)
    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

  • 197.
    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 soil1989Ingår 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. 342-353Konferensbidrag (Refereegranskat)
  • 198.
    Axelsson, Kennet
    et al.
    Professor emeritus i byggnadskonstruktion vid Uppsala universitet.
    Mattsson, Hans
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Geoteknik2016Bok (Refereegranskat)
    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.

  • 199.
    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, Victoria2019Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 1, s. 14-21Artikel i tidskrift (Refereegranskat)
    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.

  • 200.
    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, Australia2018Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 10, nr 10, s. 637-642, artikel-id 87732Artikel i tidskrift (Refereegranskat)
    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.

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