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  • 301.
    Bowman, Elisabeth T.
    et al.
    University of Canterbury.
    Imre, Bernd
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Geotechnical centrifuge modelling of debris flows2007Ingår i: International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings, 2007, s. 229-239Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 302.
    Brundin, Herman
    et al.
    SÖRAB.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rihm, Thomas
    RVF service AB.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Tham, Gustav
    Telge Återvinning AB.
    Långtidsegenskaper hos tätskikt innehållande bentonit2001Rapport (Övrigt vetenskapligt)
    Abstract [sv]

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

  • 303.
    Bui, Dieu Tien
    et al.
    Geographic Information Science Research Group, Ton Duc Thang University, Ho Chi Minh City, Minh, Vietnam. Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Minh, Vietnam.
    Asl, Dawood Talebpour
    Department of Geomorphology, Faculty of Natural Resources, University of Kurdistan, Sanandaj, Iran.
    Ghanavati, Ezatolla
    Department of Geomorphology, Faculty of Geography, University of Kharazmi, Tehran, Iran.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khezri, Saeed
    Department of Geomorphology, Faculty of Natural Resources, University of Kurdistan, Sanandaj, Iran.
    Chapi, Kamran
    Department of Watershed and Rangeland Management, Faculty of Natural Resources, University of Kurdistan, Sanandaj, Iran.
    Amini, Ata
    Kurdistan Agricultural and Natural Resources Research and Education Center, AREEO, Sanandaj, Iran.
    Pham, Binh Thai
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Effects of Inter-Basin Water Transfer on Water Flow Condition of Destination Basin2020Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 12, nr 338Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In recent years, the intensification of drought and unsustainable management and use of water resources have caused a significant decline in the water level of the Urmia Lake in the northwest of Iran. This condition has affected the lake, approaching an irreversible point such that many projects have been implemented and are being implemented to save the natural condition of the Urmia Lake, among which the inter-basin water transfer (IBWT) project from the Zab River to the lake could be considered an important project. The main aim of this research is the evaluation of the IBWT project effects on the Gadar destination basin. Simulations of the geometrical properties of the river, including the bed and flow, have been performed, and the land cover and flood map were overlapped in order to specify the areas prone to flood after implementing the IBWT project. The results showed that with the implementation of this project, the discharge of the Gadar River was approximately tripled and the water level of the river rose 1 m above the average. In April, May, and June, about 952.92, 1458.36, and 731.43 ha of land adjacent to the river (floodplain) will be inundated by flood, respectively. Results also indicated that UNESCO’s criteria No. 3 (“a comprehensive environmental impact assessment must indicate that the project will not substantially degrade the environmental quality within the area of origin or the area of delivery”) and No. 5 (“the net benefits from the transfer must be shared equitably between the area of origin and the area of water delivery”) have been violated by implementing this project in the study area. The findings could help the local government and other decision-makers to better understand the effects of the IBWT projects on the physical and hydrodynamic processes of the Gadar River as a destination basin.

  • 304.
    Bui, Dieu Tien
    et al.
    Geographic Information Science Research Group, Ton Duc Thang University, Ho Chi Minh City, Vietnam. Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Shirzadi, Ataollah
    Department of Rangeland and Watershed Management, Faculty of Natural Resources, University of Kurdistan, Sanandaj, Iran.
    Amini, Ata
    Kurdistan Agricultural and Natural Resources Research and Education Center, AREEO, Sanandaj, Iran.
    Shahabi, Himan
    Department of Geomorphology, Faculty of Natural Resources, University of Kurdistan, Sanandaj , Iran. Department of Zrebar Lake Environmental Research, Kurdistan Studies Institute, University of Kurdistan.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hamidi, Shahriar
    Department of Water Science and Engineering, Faculty of Agriculture, University of Kurdistan, Sanandaj, Iran.
    Singh, Sushant K.
    Department of Health, Insurance & Life Sciences, Data & Analytics, Virtusa Corporation, Irvington, NJ, USA.
    Pham, Binh Thai
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Ahmad, Baharin Bin
    Faculty of Built Environment and Surveying, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Ghazvinei, Pezhman Taherei
    Department of Civil Engineering, Technical and Engineering College, Ale Taha University, Tehran, Iran.
    A Hybrid Intelligence Approach to Enhance the Prediction Accuracy of Local Scour Depth at Complex Bridge Piers2020Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 12, nr 3, s. 1-24, artikel-id 1063Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Local scour depth at complex piers (LSCP) cause expensive costs when constructing bridges. In this study, a hybrid artificial intelligence approach of random subspace (RS) meta classifier, based on the reduced error pruning tree (REPTree) base classifier, namely RS-REPTree, was proposed to predict the LSCP. A total of 122 laboratory datasets were used and portioned into training (70%: 85 cases) and validation (30%: 37 cases) datasets for modeling and validation processes, respectively. The statistical metrics such as mean absolute error (MAE), root mean squared error (RMSE), correlation coefficient (R), and Taylor diagram were used to check the goodness-of-fit and performance of the proposed model. The capability of this model was assessed and compared with four state-of-the-art soft-computing benchmark algorithms, including artificial neural network (ANN), support vector machine (SVM), M5P, and REPTree, along with two empirical models, including the Florida Department of Transportation (FDOT) and Hydraulic Engineering Circular No. 18 (HEC-18). The findings showed that machine learning algorithms had the highest goodness-of-fit and prediction accuracy (0.885 < R < 0.945) in comparison to the other models. The results of sensitivity analysis by the proposed model indicated that pile cap location (Y) was a more sensitive factor for LSCP among other factors. The result also depicted that the RS-REPTree ensemble model (R = 0.945) could well enhance the prediction power of the REPTree base classifier (R = 0.885). Therefore, the proposed model can be useful as a promising technique to predict the LSCP.

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

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

  • 306.
    Camerlenghi, A.
    et al.
    University of Barcelona.
    Ask, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dugan, B.
    Rice University, Houston.
    Kopf, A.
    MARUM, Bremen.
    Morgan, J.
    Rice University, Houston.
    Suyehiro, K.
    JAMSTEC.
    Urgeles, R.
    University of Barcelona.
    Good reasons for IODP to address submarine geohazards: (with focus on the Mediterranean)2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Following a number of international workshop held in the last few years, this documents synthesise the reasons why future scientific ocean drilling should prioritize geohazards among the scientific objectives. In essence the reasons are the societal relevance, the opportunity to deepen the knowledge of basic geological processes in basin evolution, and the opportunity for technological development. A focus in placed on the Mediterranean Basin because of its high vulnerability to submarine geohazards, and to the known widespread occurrence (in the present and in the recent geological record) of geohazards. Among geohazards of the Mediterranean, a focus is placed on the submarine landslides because of their potential to affect seabed structure and the coastline via the tsunamis they can generate. A list of technological needs and a list of the international workshops is added for reference at the end of the document.

  • 307. Carlsson, B.
    et al.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Andersson, Y.
    Lindfors, U.
    The failure process and the acoustic emission of brittle rock under compression1999Ingår i: 9 Congres international de mecanique des roches : comptes-rendus : Paris, France, 1999 / [ed] Gérard Vouille, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1999, s. 569-572Konferensbidrag (Refereegranskat)
  • 308.
    Carlsson, Torbjörn
    et al.
    Luleå tekniska universitet.
    Jacobsson, Arvid
    Luleå tekniska universitet.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ofruset vatten i frusen jord: exempel på praktikansluten grundforskning vid avdelningen för geoteknik vid högskolan i Luleå.1982Ingår i: Väg- och Vattenbyggaren, ISSN 0042-2177, nr 1, s. 33-35Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 309.
    Chabuk, Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Solid Waste Landfills in an Arid Environment : Site Selection and Design2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Selecting landfill sites is considered a complicated task because its whole process is based upon several factors and restrictions. This study shows the present status of solid waste management, sources, collection personnel, machinery and equipment that are involved in the waste collection process, financing and financial management for the major cities of the Babylon Governorate in Iraq (Al-Hillah, Al-Qasim, Al-Mahawil, Al-Hashimiyah and Al-Musayiab). The management of waste collection and disposal in the Babylon Governorate and its districts is through open waste dumps, so the quality of the collection and disposal process is poor, and these sites do not conform to the scientific and environmental criteria usually applied in the selection of landfill sites.

    In the first part of the current study, three methods were used to calculate the solid waste quantity for each specific year up to the year 2030 as well as the cumulative quantity of solid waste for the period (2020-2030) for Babylon Governorate. The results show the cumulative quantity of solid waste resulting from (method 3) receives a high value compared to other methods, and so it is used as a maximum value to estimate the required area for candidate sites for landfills in each district. The generation rate in 2030 will be (0.97, 0.69, 0.48, 0.62 and 0.91) (kg/capita/day) in (Al-Hillah, Al-Qasim, Al-Mahawil, Al-Hashimiyah and Al-Musayiab), respectively, based on method 3, where the estimated annual incremental generation rate is 1 %. 

    The second part of this study aims to find the best sites for landfills in the arid areas that are distinguished by a shallow depth of groundwater. The Babylon Governorate was selected as a case study because it is located in an arid area, and the depths beneath the ground surface to the groundwater level are shallow.  

    For this purpose, 15 important criteria were adopted as follows: groundwater depth, rivers, soil types, agricultural land use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centers, villages and archaeological sites. These criteria were then entered into the geographic information system (GIS). The GIS software has a large capacity to manage and analyze various input data using special analysis tools. In addition, Multi-Criteria Decision Making (MCDM) methods were used to derive the relative weightings for each criterion in different styles. These methods are (Analytical Hierarchy Process (AHP), Simple Additive Weighting (SAW), Ratio Scale Weighting (RSW) and Straight Rank Sum (SRS)).

    Raster maps of the selected criteria were prepared and analyzed within the GIS software. The final map for candidate landfill sites was obtained through combining the GIS software and (MCDM) methods. Subsequently, comparison methods (Change Detection, Combination, Kappa and Overall Assessment) for each pair of raster maps that result from using the two different methods of multi-criteria decision making were implemented to determine the pixel percentage of matching and non-matching as well as to determine and check the suitability of the selected sites for landfills on both resulting maps using two methods.  

    Two suitable candidate sites for landfills were determined to fulfill the scientific and environmental requirements in each major city. These areas are (6.768 and 8.204) km2 in Al-Hillah, (2.766 and 2.055) km2 in Al-Qasim, (1.288 and 1.374) km2 in Al-Hashimiyah, (2.950 and 2.218) km2 in Al-Mahawil, and (7.965 and 5.952) km2 in Al-Musayiab. The required area of the selected sites can accommodate solid waste from 2020 until 2030 based on the required areas according to the third method.

    The third part of this study includes soil investigations for the selected landfill sites. The suggested design should ensure that there is no groundwater pollution by leachate from these sites because the groundwater depth is very shallow in the Babylon Governorate. To avoid this problem, soil investigation was conducted at these sites so that the most suitable landfill design could be established. Each site was subjected to field soil tests to find the composition of the soil strata at each site to a depth of 10 m, and these results were compared with the soil properties adopted for final site selection. The Iraqi Ministry of Housing & Construction, National Centre for Construction Laboratories and Research Babylon, Iraq, carried out the analytical work on the soil in 2016. The results of the soil investigation at these sites include the soil profile, groundwater depth, chemical properties, allowable bearing capacity, atterberg limits test results and material characteristics of the soil strata. According to the results of these tests, the best design is the one that puts the compacted waste at the surface.

    The fourth part of this study covers the selection of a suitable proposed design in the arid areas (Babylon Governorate, Iraq) for the selected landfill siting. In the current study, the design of this landfill includes the suggested soil layers for the liner system and final cover system.  

    For the base liner system (from the bottom toward the top), the composite bottom barrier layer consists of highly compacted sandy clay. The thickness of the bottom barrier layer is 60 cm, and its saturated hydraulic conductivity is 1.0E-7cm/s. The 1.5 mm thick geomembrane (HDPE), with hydraulic conductivity of 2.0E-13 cm/s, is placed over the composite bottom barrier layer. The leachate collection system consists of drainage layer (gravel) with a thickness of 30 cm and a hydraulic conductivity of 3.0E-1 cm/s. The diameter of the main drainpipes is between 15 and 20 cm. The protection layer consists of sand material, and its hydraulic conductivity is 5.0E-3 cm/s. The thickness of the protection layer is 30 cm.

    The compacted solid waste is placed upon the surface to a height of 2 m because of the shallow groundwater depth and to avoid groundwater contamination by leachate from the landfill site. The density of the compacted waste is 700 kg/m3, and its saturated hydraulic conductivity is 1.0E-5 cm/s.

    Three scenarios were used for the suggested designs for the final cover system of the landfills in arid areas. The first scenario was “evapotranspiration soil cover (ET) (capillary barriers type)”, the second scenario was a modified cover design of "RCRA Subtitle D", and the third scenario was the “Recommended design”. In this study, “Recommended design”, the third scenario for the final cover system, was adopted in the arid area (Babylon governorate, Iraq) based on combining certain layers from the first and second scenarios. For the three scenarios, the soil components in these designs used was based on available local materials in the study area. The layers of the base liner system were adopted in all scenarios.

    The third scenario for the final cover system, “Recommended design”, was implemented based on weather parameters in the arid areas. The water infiltrated from the surface of landfill is stored within upper layers that have fine particles. This allows the stored water to evaporate from the soil surface of the landfill or transpire through vegetation due to the high temperature during most months in the study area. The water that enters from the surface of the landfill should be contained above the geomembrane liner and top barrier layer without leakage into the waste body, thereby preventing leachate generation.

    For the layers of the final cover system (from the bottom to the top), the intermediate cover is used to cover the waste body, and this layer consists of moderate compacted silty clayey loam (native soil). The thickness of the intermediate cover is 30 cm, and its saturated hydraulic conductivity is1.0E-6 cm/s. The foundation layer consists of coarse sand material with a thickness of 30 cm and a saturated hydraulic conductivity of 1.0E-2 cm/s. This layer acts as a cushion for the layers of the final cover system. The gas collection system can be installed within the foundation layer.  

    The top barrier layer is placed over the foundation layer. This layer consists of highly compacted sandy clay of (45 - 60 cm) thickness with compacted lifts (each lift is 15 cm). The saturated hydraulic conductivity of the barrier layer is 1.0E-7 cm/s. The geomembrane liner, (HDPE) of 0.5 cm thickness and a saturated hydraulic conductivity of 2.0E-13 cm/s, is put on top of the barrier layer. The upper layers of the final cover system are the support vegetation layer and the topsoil layer. The composition of the support vegetation layer is moderate compacted loam. This layer is placed directly on the geomembrane liner. The saturated hydraulic conductivity of the support layer is1.0E-5 cm/s, and its thickness is 45 cm. The topsoil layer consists of silty clayey loam, and it is placed over the support vegetation layer with a slope of 3%. The thickness of the topsoil layer is 15 cm, and its hydraulic conductivity is 4.0E-5 cm/s.  

    The Hydrologic Evaluation of a Landfill Performance (HELP 3.95 D) model was applied to the selected landfill sites in the governorate to check if there could be any infiltration of the leachate that will result from the waste in the landfills in the selected sites in the future. The HELP model, which utilizes both weather and soil data, is the most commonly used model for landfill design, and it is employed to evaluate the quantity of water inflow through soil layers for the designed landfill. This suggested landfill is designed using the weather parameters (rainfall, temperature, solar, and the required date to calculate evapotranspiration) for the 12 consecutive years from 2005 to 2016, as well the required data for soil design.

    In the HELP model, the result for the suggested landfill design for both the recommended design (third scenario) and the second scenario was a modified cover design of "RCRA Subtitle D", which showed there was no leachate through the soil sub-layers, including the bottom barrier layer. The proposed design for the final cover system showed a reduction in the surface runoff and an increase in actual evapotranspiration. In the first scenario “evapotranspiration soil cover (ET) (capillary barriers type)”, there was no leachate percolation through the bottom barrier layer during the study years, apart from in 2013 and 2014. In these years, water percolation figures were 1.4E-5 and 4.0E-6 mm, respectively. These values are considered small, and they resulted from the high rate of rainfall during these years. Although, these values were small, they should still be taken into consideration when adopting this design in the study area.

    In the HELP model, the average annual and peak daily results for all scenarios showed that there was no water percolation through the bottom barrier layer during the years from 2005 to 2016.

  • 310.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Alkaradaghi, Karwan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Kurdistan Institution for strategic studies and scientific Research, Sulaimaniyah, Iraq.
    Al-Rawabdeh, Abdulla Mustafa Muhamed
    Abdullah Mustafa Muhamed Al-Rawabdeh, Department of Earth and Environmental Science, Yarmouk University, Irbid, Jordan.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa, Iraq; Department of Geology, Faculty of Science, University of Kufa, Kufa, Iraq.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Final Cover Systems Design for Arid Areas Using the HELP Model: A Case Study in the Babylon Governorate, Iraq2018Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 12, artikel-id 4568Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 311.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon 51001, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ezz-Aldeen, Mohammad
    Department of Dams and Water Resources Engineering, University of Mosul, Mosul 41001, Iraq.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa 51001, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Two Scenarios for Landfills Design in Special Conditions Using the HELP Model: A Case Study in Babylon Governorate, Iraq2018Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 1, artikel-id 125Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 312.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Kamaleddin, Suhair
    Iraqi Ministry of Housing & Construction, National Center for Construction Laboratories and Research Babylon, Baghdad.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Soil Characteristics in Selected Landfill Sites in theBabylon Governorate, Iraq2017Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 11, nr 4, s. 348-363Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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

  • 313.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of ScienceUniversity of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    GIS-based assessment of combined AHP and SAW methods for selecting suitable sites for landfill in Al-Musayiab Qadhaa, Babylon, Iraq2017Ingår i: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 76, nr 5, artikel-id 209Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 314.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, College of Science, Kufa University.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Sites Selection Using AnalyticalHierarchy Process and Ratio ScaleWeighting: Case Study of Al-Mahawil,Babylon, Iraq2017Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 2, s. 123-141Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 315.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Present Status of Solid Waste Management at Babylon Governorate, Iraq2015Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 7, s. 408-423Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 316.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Sitting by Two Methods in Al-Qasim, Babylon, Iraq and Comparing Them Using Change Detection Method2017Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 8, s. 723-737Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 317.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, college of Engineering, U niversity of Babylon, Babylon, Iraq. .
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain M.
    Remote Sensing Center, University of Kufa, Kufa, Iraq.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hazim, Anwer
    Koya university, Koya, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Sites Selection Using MCDM and Comparing Method of Change Detection for Babylon Governorate, Iraq2019Ingår i: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 26, nr 35, s. 35325-35339Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 318.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill site selection using geographic information system and analytical hierarchy process: A case study Al-Hillah Qadhaa, Babylon, Iraq2016Ingår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 34, nr 5, s. 427-437Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 319.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfill Siting Using GIS and AHP (Analytical Hierarchy Process): A Case Study Al-Qasim Qadhaa, Babylon, Iraq2016Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 5, s. 530-543Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 320.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussain, Hussain Musa
    Department of Geology, Faculty of Science, University of Kufa.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Combining GIS Applications and Method of Multi-Criteria Decision-Making (AHP) for Landfill Siting in Al-Hashimiyah Qadhaa, Babylon, Iraq2017Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, nr 11, artikel-id 1932Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 321.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hussein, Hussein M.
    Luleå tekniska universitet.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Landfills Site Selection in Babylon, Iraq2017Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 7, nr 4, s. 1-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 322.
    Chabuk, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Alkaradaghi, Karwan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Kurdistan Institution for Strategic Studies and Scientific Research, Sulaimaniyah, Iraq.
    Hussain, Hussain M.
    Remote Sensing Center, University of Kufa, Department of Geology, Faculty of Science, University of Kufa, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of the HELP Model for Landfill Design in AridAreas: Case Study Babylon Governorate, Iraq2018Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 12, nr 12, s. 848-879Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 323.
    Chen, Guanghui
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Li, Xibing
    School of Resource and Safety Engineering, Central South University, Changsha, Hunan.
    Zhang, Ping
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dong, Longjun
    School of Resource and Safety Engineering, Central South University, Changsha, Hunan.
    Optimization of tunnel support parameters with consideration of seismic wave radiation pattern in the fault-slip burst2017Ingår i: Journal of Mining and Safety Engineering, ISSN 1673-3363, Vol. 34, nr 4, s. 715-722Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As the underground mining extends gradually towards depth, more and more seismic events induced by fault slip occur and cause great damages, which have become a severe potential threat to mining safety. In view of the plane strain problems, through the three dimensional discrete model established, comparison and analysis was carried out between the equivalent calculation of plane strain in 3D model and a 2D discrete model. The results have shown that the research model developed to simulate the propagation of seismic wave in 3D is feasible and applicable. The study of the effect of radiation pattern on seismic propagation revealed and tested the direction of P-and S-wave propagation, which presents high consistency to double couple model of the fault slip. On this basis, the comparison with the design scaling law formulas proposed by Kaiser and associates finds that the existing design scaling law does not totally satisfy the demand of practical engineering. Numerical calculation and analysis with the three dimensional discrete model can further optimize the support parameters, provide better service for system design of mining support, and ensure the safety and high efficiency in mining.

  • 324.
    Chen, Jian
    et al.
    School of Engineering, The University of Newcastle, Callaghan, Australia.
    Orozovic, Ognjen
    School of Engineering, The University of Newcastle, Callaghan, Australia. Centre for Bulk Solids and Particulate Technologies, Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, Australia.
    Kenneth, Williams
    School of Engineering, The University of Newcastle, Callaghan, Australia. Centre for Bulk Solids and Particulate Technologies, Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, Australia.
    Meng, Jingjing
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Li, Chengzhi
    The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, China. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan, China.
    A coupled DEM-SPH model for moisture migration in unsaturated granular material under oscillation2020Ingår i: International Journal of Mechanical Sciences, ISSN 0020-7403, E-ISSN 1879-2162, Vol. 169, artikel-id 105313Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Granular materials, such as mineral products, soil and chemical fertilizer, normally contain unsaturated free moisture. This unsaturated moisture could migrate in the granular material and its processing, resulting in handling and safety concerns due to a change in the material properties. In this work, a method of coupling the Discrete Element Method (DEM) and the Smoothed Particle Hydrodynamics (SPH) was proposed to investigate moisture migration in unsaturated granular materials under oscillation. The particles and water were simulated through DEM and SPH, respectively and a python coupling framework was programmed to perform the exchange of particle-fluid interaction forces. Subsequently, experiments with plastic pellets and a coal sample were used to calibrate the models, with DEM calibrated by an angle of repose experiment and draining experiments calibrating the coupled model. Finally, the coupled model was validated by comparing the results to those of experiments involving moisture migration under oscillation. It was found that, compared to measurements, the coupled SPH-DEM model predicted the same moisture migration trend and also provided good agreement for the prediction of the mass of drained water.

  • 325.
    Chen, Jun Fang
    et al.
    Luleå Tekniska Högskola.
    Ouchterlony, Finn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Stephansson, Ove
    Luleå Tekniska Högskola.
    A compre­hensive fracture mechanics model of rock: experimental set up and preliminary results1992Rapport (Övrigt vetenskapligt)
  • 326.
    Chen, Xu-Guang
    et al.
    Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing.
    Wang, Yuan
    Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing.
    Zhang, Qiang-Yong
    Research Center of Geotechnical and Structural Engineering, Shandong University, Jinan.
    Li, Shu-Cai
    Research Center of Geotechnical and Structural Engineering, Shandong University, Jinan.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Analogical model test and theoretical analysis on zonal disintegration based on filed monitoring in deep tunnel2013Ingår i: European Journal of Environmental and Civil Engineering, ISSN 1964-8189, E-ISSN 2116-7214, Vol. 17, nr Suppl. 1, s. 33-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Field monitoring carried out in a deep tunnel of the Dingji coal mine in China confirmed the zonal disintegration phenomenon by using the borehole TV. Based on field monitoring, an analogical model test was conducted to research the fracture shape and forming conditions of the rock mass in the Dingji mine. To perform the model test, an analogical material and optical sensor were developed independently. Through the test, the occurrence of zonal disintegration was confirmed and the forming process was monitored. The fracture pattern of zonal disintegration was determined, and the radii of the fractured zones were found to fulfil the relationship of geometric progression. The displacement laws of surrounding rocks during zonal disintegration were obtained and found to be non-monotonic. The test results are in agreement with the field-monitoring results. Through a theory analysis based on fracture mechanics, the mechanism of zonal disintegration was revealed. The fracture zones occur as circles concentric to the cavern periphery, which is the “false face”. Each fracture zone ruptures at the elastic–plastic boundary of surrounding rocks and then coalesces into a circle. The geometric progression ratio was determined; it is related to the mechanical parameters and ground stress of the surrounding rocks and calculated as follows: And the mechanism of the non-monotonic displacement law is revealed; the continuous formation of the “false face” causes the geostress redistribution and crack opening.

  • 327.
    Chikatamarla, R.
    et al.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Springman, Sarah M.
    Institute for Geotechnical Engineering, Eidgenossische Technische Hochschule Zurich.
    Stress distribution of rockfall events on galleries2005Ingår i: Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering: Geotechnology in Harmony with the Global Environment, 2005, Vol. 4, s. 2789-2792Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 328.
    Christiansson, Rolf
    et al.
    SKB.
    Olsson, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Nyberg, Ulf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Niklasson, Bengt
    Skanska Teknik, Göteborg.
    Studier av sprängskador i Äspö-laboratoriet2005Ingår i: Bergsprängningskommittén Diskussionsmöte BK 2005, Bergsprängningskommittén , 2005, s. 139-152Konferensbidrag (Övrigt vetenskapligt)
    Abstract [sv]

    En ny tunnel med 70 m längd byggdes på 450 m djup i Äspölaboratoriet 2003. Det ställdes speciella krav på begränsning av sprängskadezonens djup med hänsyn till planerade experiment.Tunneln drevs med galleri och bågformad låg pall för att minimera sprängskador i sulan. I huvuddelen av tunneln användes initieringsystemet Nonel MS och LP. I de tre sista salvorna av galleriet testades elektroniksprängkapslar. Skonsamhetsgraden för vägg och tak var normal med en tillåten skadezon på 0,3 m. Däremot tillämpades samma skonsamhetsgrad även för botten. I övrigt användes normal sprängteknik och normala sprängämnen som Dynotex 17 och Dynorex.Arbetet följdes noggrant genom dokumentation av utfört arbete. Vibrationsmätningar utfördes på nära håll samt på stort avstånd, 1,5 km från arbetsplatsen. Språng¬skador har undersökts genom sågning och sprickkartering.Föredraget kommer att presentera projektet, framförallt (1) erfarenheter från vibra¬tionsmätningar av samtliga sprängsalvor (noggrannheten i geofonmätningarna; totala antalet spränghål i salvorna; bomsalvor; avståndet från salvorna och geo¬logiska strukturer), (2) P-vågshastigheten i tunnelns närområde, (3) faktorer som påverkar utvecklingen av sprängskador, och (4) förslag på kontrollåtgärder som kan leda till att begränsa skadezonen i praktiskt tunnelarbete.

  • 329. Christiansson, Rolf
    et al.
    Olsson, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Nyberg, Ulf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Niklasson, Bengt
    Studies of blast damage at the Äspö Hard Rock Laboratory2005Ingår i: 3rd European Federation of Explosives Engineers (EFEE) World Conference on Explosives and Blasting, 2005, s. 425-434Konferensbidrag (Refereegranskat)
  • 330.
    Dagli, Deniz
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laboratory Investigations of Frost Action Mechanisms in Soils2017Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

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

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

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

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

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

  • 331.
    Dagli, Deniz
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zeinali, Amin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Gren, Per
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Image analyses of frost heave mechanisms based on freezing tests with free access to water2018Ingår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 146, s. 187-198Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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

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

  • 332.
    Dagli, Deniz
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zeinali, Amin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Edeskär, Tommy
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Theoretical Analysis of the Relationship between Heave and Net Heat Extraction Rates Based on Freezing Experiments2016Ingår i: Proceedings of Nordic Conference on Soil Mechanics and Geotechnical NGM: Reykjavik, Iceland 25th – 28th of May 2016, 2016, s. 411-421Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 333.
    Danielsson, Markus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ghosh, Rajib
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Navarro Miguel, J.
    Universidad Politechnica de Madrid.
    Johansson, Daniel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Schunnesson, Håkan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Utilizing production data to predict operational disturbances in sublevel caving2017Ingår i: Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017 / [ed] Behzad Ghodrati, Uday Kumar, Håkan Schunnesson, Luleå: Luleå tekniska universitet, 2017, s. 139-144Konferensbidrag (Refereegranskat)
  • 334.
    Danielsson, Markus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Johansson, Daniel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Schunnesson, Håkan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The Influence of Blast Fragmentation on Loadability in Sublevel Caving2018Ingår i: Proceedings of the forty-forurth annual conference on explosives and blasting technique / [ed] Kevin Hachmeister, 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    In sublevel caving, blasted material flows gravitationally into the drawpoint from above in a periodical manner. This type of flow behavior entails muck pile conditions that are variable along the course of extraction. The effect of this variability on the LHD (Load-Haul-Dump) operation in terms of loading efficiency and ability to undermine the blasted ring is not fully understood as of today. This paper presents results from a field test in LKABs Malmberget mine in Sweden, where the influence of fragmentation on the loading operation has been studied in detail. Drawpoint filming was conducted for extraction of two rings equivalent of roughly 10000 metric tons (~9842 long tons) of material each. The analysis includes fragmentation measurements, muck pile classification, and general estimations in terms of loadability. Further, an evaluation of LHD machines from two different manufacturers was conducted to identify and highlight differences. The results show that fragmentation, muck pile compactness, and flow characteristics are all interdependent. Flow disturbances and the subsequent loading of compacted fine material in the back of the ring have been identified as the main reason for occurring problems and prolonged digging times. However, the ability to sufficiently undermine the blasted ring has been identified to primarily depend on digging depth which is only observed to be high during flow disturbances. An absence of flow disturbances seem to promote high loading efficiency but simultaneously limit the maximum digging depth. A mid-range particle size distribution with a low amount of fines has proven beneficial for overall loading efficiency. The various LHDs employed showed significant variations in terms of ability to handle difficult loading situations (e.g. compactness, boulders, etc.).

  • 335.
    Darwesh, Ali K.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Maack Rasmussen, Thorkild
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kicks controlling techniques efficiency in term of time2017Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 5, s. 482-492Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 336.
    Darwesh, Ali K.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Time Optimizing near the Pay Zone2017Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 10, s. 848-858Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 337.
    Darwesh, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Controllable drilling parameter optimization for roller cone and polycrystalline diamond bits2019Ingår i: Journal of Petroleum Exploration and Production Technology, ISSN 2190-0558, E-ISSN 2190-0566Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Oil well drilling data from 23 oil wells in northern Iraq are analyzed and optimized controllable drilling parameters are found. The most widely used Bourgoyne and Young (BY) penetration rate model have been chosen for roller cone bits, and parameters were extracted to adjust for other bit types. In this regard, the collected data from real drilling operation have initially been averaged in short clusters based on changes in both lithology and bottom hole assemblies. The averaging was performed to overcome the issues related to noisy data negative effect and the lithological homogeneity assumption. Second, the Dmitriy Belozerov modifications for polycrystalline diamond bits compacts have been utilized to correct the model to the bit weight. The drilling formulas were used to calculate other required parameters for the BYM. Third, threshold weight for each cluster was determined through the relationship between bit weight and depth instead of the usual Drill of Test. Fourth, coefficients of the BYM were calculated for each cluster using multilinear regression. Fifth, a new model was developed to find the optimum drill string rotation based on changes in torque and bit diameter with depth. The above-developed approach has been implemented successfully on 23 oil wells field data to find optimum penetration rate, weight on bit and string rotation.

  • 338.
    Darwesh, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of Limestone Interval in the Drilled Surface Section of Bn-1 Oil Well2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 8, s. 515-524Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 339.
    Darwesh, Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rasmussen, Thorkild Maack
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Wiper Trips Effect on Wellbore Instability Using Net Rising Velocity Methods2018Ingår i: Open Petroleum Engineering Journal, ISSN 1874-8341, Vol. 11, s. 14-28Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: This paper discusses the wiper trip effects on well instability in shale formations.Objectives: Problematic shale interval sections have been studied for the time spent on the wiper trip operations. Lifting efficiency and well wall instability change with the time analyzed. Detailed drilling operation, formation heterogeneity, rheological and filtration characteristics of polymer water-based mud are discussed. Physical and chemical properties of the drilled formation and drilling fluid are also studied.Materials and Methods: Wiper trips are analyzed using a typical drawing program to find the relations between the most controllable parameters. For that, two calculation models have been implemented to find the net rising cutting particles velocity in the annular. The relation between the net rising velocity and wiper trips is analyzed. Laboratory works have been done to support the findings of field work.Results: Strong relations have been found between the wiper trip impacts and lithology types of the penetrated shale.Conclusion: A modified drilling program is proposed in relation to changes in casing setting depth and drilling fluid properties that make the operations more efficient in cost and time.

  • 340.
    Dineva, Savka
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Boskovic, Mirjana
    LKAB.
    Evolution of seismicity at Kiruna Mine2017Ingår i: Deep Mining 2017: Eighth International Conference on Deep and High Stress Mining / [ed] J Wesseloo, Perth: Australian Centre for Geomechanics , 2017, s. 125-140Konferensbidrag (Refereegranskat)
    Abstract [en]

    Kiirunavaara (Kiruna) iron ore mine owned by LKAB (Sweden) is one of the largest underground mines. Miningstarted in 1898 as an open pit mine. In mid-1950, the mine started a transition to underground mining andpassed to only underground mining in 1962. More substantial problems with seismicity started in 2007-2008when the deepest mining level was 907 m (ca. 670 m below surface). By 2016, the mining production is at1,022–1,079 m Level (ca. 785–845 m below surface). More than one billion tonnes of ore have been extractedsince the beginning of mining. The average yearly production in recent years is 28 million tonnes.By 2016 the mine has the largest underground seismic system in the world with 204 operational geophones.The number of the sensors (geophones with natural frequencies of 4.5, 14, and a few of 30 Hz) changed withthe increasing of production depth. The major stages with seismic system upgrades are: August 2008–June2009 with 112 installed geophones, and July 2012–September 2013 with 95 installed geophones. During2016–2017 it is planned to install some additional 45 geophones.The study was carried out to identify some trends in seismicity as the mining goes deeper and to find thecorrelation with some main controlling parameters – volume and depth of the production in order to obtaininformation for future seismic hazard and risk analysis. Custom made applications within mXrap were utilisedto carry out the spatial variations of seismicity.The analysis showed substantial difference between the seismicity in the three studied blocks – 15/16, 28/30,and 33-37/34, with the weakest seismic activity in Block 15/16 (Mmax 1.6, maximum observed magnitude),followed by Block 28/30 (Mmax 2.2), and then largest seismicity in Block 33-37/34 (Mmax 2.2). The dailyseismicity rate increased substantially through the years only for Block 33-37/34. The seismicity correlatesstrongly with the production depth. In general a straightforward correlation between the production volumeand number of larger events (M > 0) was not found for the three studied blocks, assuming there are otherfactors affecting the seismicity, e.g. geological structures, areas with contrast in geomechanical properties,etc. The spatial variations of some seismic source parameters were traced for varying periods of time,depending on the major production stages (opening of new levels, full production, closing) for the threeblocks. The distributions of the cumulative seismic energy showed a maximum around and below theproduction. The cumulative seismic moment and number of events in most cases showed a maximum aroundand above the production, indicating caving in these areas. The static stress drop shows the largest valuesaround and below the production on the footwall side, corresponding also to the areas with increased stress.The energy index showed increased stresses in the same areas (EI > 1).This study is only the first overview of the seismicity in Kiruna Mine. For seismic hazard assessment and riskanalysis further more detailed studies with smaller time intervals need to be carried out to obtain more precisecorrelations between the seismic parameters and the production volume and depth, and other possible factorsaffecting seismicity (geological structures, areas with contrast geomechanical properties, etc.).

  • 341.
    Dineva, Savka
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mihaylov, Dimitar
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hansen-Haug, Jouni
    Lundin Mining.
    Nyström, Anders
    Boliden AB.
    Woldemedhin, Biruk
    LKAB.
    Local seismic systems for study of the effect of seismic waves on rock mass and ground support in Swedish underground mines (Zinkgruvan, Garpenberg, Kiruna)2016Ingår i: Proceedings of the 8th International Symposium on Ground Support in Mining and Underground Construction / [ed] E . Nordlund, T.H. Jones and A. Eitzenberger, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Three local seismic systems were installed by August 2015 in deep underground mines in Sweden – Zinkgruvan Mine (Lundin Mining AB), Garpenberg Mine (Boliden AB), and Kiirunavaara Mine (LKAB) as part of a project for developing new methods for Evaluating the Rock Support Performance (ERSP, Vinnova). The areas were chosen within the most probable volumes where large rockbursts can be expected. The local systems were installed at mine levels between 730 and 1150 m in different mines. The horizontal extend of each instrumented areas is between 70 and 100 m. The seismic system in each mine is a combination of uni-axial and three-axial 4.5 Hz geophones installed on the surface, in shallow (~0.5 m) and deeper (6-9 m) boreholes in profiles across drifts. These profiles are in close proximity to profiles with extensometers, instrumented bolts, and observation holes. The seismic systems are manufactured and installed by the Institute of Mine Seismology (IMS). The aim of the seismic systems is to record the seismic events that occur in the vicinity of the instrumented areas and provide valuable data about the variability of seismic waveforms around the underground openings and changes when seismic waves approach them. Data is used to study: 1) the attenuation/decrease of the maximum ground velocity (PPV) with the distance, especially at small distances; 2) site effects, including maximum amplitudes, predominant frequency, and duration of the seismic signals, 3) the attenuation/amplification of the seismic waves approaching the underground opening. The final aim is to obtain new information that can be used for improved requirements for the rock support design in rockburst prone areas.The installation of the seismic systems started in May 2015 (Zinkgruvan Mine) and was completed by August 2015. They run mostly in triggered mode with initial automatic arrival time picking and source parameter calculation and subsequent manual processing of seismic event of interest. More than 200,000 seismic events with magnitude from -4.5 to 2.0 were recorded by December 2015. At present only a small portion of all data was processed manually and the procedures for processing of the events were developed on this subset. The first results from the monitoring showed that there are differences in the amplitudes and shape of the seismic signals recorded by the sensors installed in deeper borehole (behind the most blast-damaged zone (6 – 9 m)) and close to the surface (0.5 m) or on the surface of the openings. There are also differences between the waveforms recorded on the walls and the roof along the same profiles or on nearby profiles. Data from the investigated rockbursts showed maximum velocity recorded from a seismic events at close distances with magnitude larger than 0.5 in the order of 10 cm/s with clipping levels 10 – 20 cm/s.

  • 342. Domaschuk, L.
    et al.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Rahman, M.G.
    Shields, D.H.
    Creep of frozen sand under isotropic and deviatoric components of stress1985Ingår i: Journal of energy resources technology, ISSN 0195-0738, E-ISSN 1528-8994, Vol. 107, nr 2, s. 199-203Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The creep behavior of frozen soil is being studied by examining its response to changes in the mean normal stress and changes in the deviatoric components of stress, using separate tests.^The two response components will then be coupled to provide a model for a general stress state.^The paper contains the results of three triaxial compression creep tests on frozen sand (T=-3 C) in which the samples were subjected to changes in the deviatoric components of stress only. Stepwise stress increases were applied for periods up to 1700 hr during which volumetric and axial strains were measured. The samples underwent attenuating creep when subjected to low stress levels and accelerating creep when subjected to higher stress levels, with no indication of a significantly long period of steady-state creep.The samples underwent volume reduction when the axial strains were attenuating and dilated when the axial strain rates began to accelerate.

  • 343. Dury, Robin
    et al.
    Bernander, Stig
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Kullingsjö, Anders
    Skanska Teknik AB.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Progressive Landslide Analysis with Bernander Finite Difference Method2017Ingår i: / [ed] Vikas Thakur, Jean-Sébastien L’Heureux, Ariane Locat, 2017, s. 1-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

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

    It includes:

    - Material Properties

    - Finite Difference Method

    - Progressive failure process with five phses

    - Discussion

    - References

  • 344.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Bestämning av bergmassans hållfasthet med hjälp av bergkaraktärisering2004Ingår i: Bergmekanikdag 2004 Föredrag, SweBeFo , 2004, s. 41-51Konferensbidrag (Övrigt vetenskapligt)
    Abstract [sv]

    Kunskapen om bergmassans lastbärande förmåga är viktig vid utformning av alla former av underjordsanläggningar. I denna studie har befintliga karaktäriserings- och klassificeringssystem samt brottkriterier kritiskt granskats med avseende på tillämpbarhet för att bedöma hållfastheten av hårda bergmassor. De viktigaste styrande faktorerna/parametrarna för bergmassans hållfasthet har identifierats och beskrivits. Befintliga brottkriterier har utvärderats genom en kritisk fallstudie, uppdelad i två delar. Den första delen består av ett s.k. "Round Robin Test", där ett antal bergmekaniker har, baserat på samma indata, uppskattat hållfastheten med hjälp av några utvalda karaktäriseringssystem och brottkriterier. Två fall studerades - en pelare från Laisvallgruvan och en fiktiv bergmassa med en djupt belägen tunnel. Den andra delen av fallstudien behandlar hållfasthetsbedömning av ett storskaligt test från Stripa. Fallstudien nyttjades för att identifiera vilka brottkriterier som är robusta, vilka parametrar/faktorer som är viktiga samt vilka faktorer som i de befintliga systemen/kriterierna är känsliga för variationer och/eller har en beskrivning som ger en stor spridning i resultatet. Baserat på fallstudierna identifierades de mest användbara och robusta kriterierna och karaktäriseringssystemen för uppskattning av bergmassans hållfasthet.

  • 345.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Different approaches for simulating brittle failure in two hard rock mass cases: a parametric study2010Ingår i: Rock Mechanics and Rock Engineering, ISSN 0723-2632, E-ISSN 1434-453X, Vol. 43, nr 2, s. 151-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    One of the aims of rock mechanics analysis is to predict fallouts in underground excavations. The objective of this paper was to study the relative importance of different strength parameters and their significance on the simulation of brittle failure and fallouts. This work was conducted as a parametric study, using numerical modelling and a number of approaches. The results were compared with observed fallouts. More obvious and distinct shear bands could be observed with decreased element sizes close to, and at, the boundary. The maximum shear strain was the most reliable indicator for fallout prediction. The results of the (instantaneous) cohesion softening friction softening models were sensitive to changes of the peak strength parameters and less sensitive to variations in residual parameters. The result from the cohesion-softening friction-hardening (CSFH) model, when using a peak cohesion equal to the intact rock strength, best captured the observed rock behaviour.

  • 346.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of rock mass strength criteria2004Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Knowledge of the rock mass behaviour in general, the failure process and the strength in particular, is important for the design of all kinds of underground excavations. One of the most common ways of estimating the rock mass strength is by using a failure criterion. The existing rock mass failure criteria are stress dependent and often include one or several parameters that describe the rock mass properties. These parameters are often based on classification or characterisation systems. A comprehensive literature review of existing classification/characterisation systems and rock mass failure criteria has been performed. As the application of this licentiate thesis is for hard rock masses some limitations have been stated on the systems and criteria. The limitations of the classification/ characterisation systems are that they should present a result that is relevant for the strength, give a numerical value, have been used after the first publication and be applicable to hard rock masses. Based on the literature review, it was concluded that the uniaxial compressive strength, block size and shape, joint strength and a scale factor are the most important parameters that should be used when estimating the rock mass strength. Existing rock mass failure criteria and classification/characterisation systems have been evaluated through the use of case studies. The aim of the case studies was to identify robust systems and criteria, parameters having the strongest impact on the calculated rock mass strength and those giving a large interval of the result. The case study revealed that the rock mass quality (Q-system), rock mass Number (N-system), Rock Mass index (RMi) system, Yudhbir – Rock Mass Rating (RMR76) and Hoek-Brown – Geological Strength Index (GSI) seem to be the most suitable systems and criteria to use when determining the rock mass strength. None of the systems or criteria complies with the requirements of a method to determine the rock mass strength and a better rock mass strength estimation method should be developed. This requires more case histories where the determined/estimated rock mass strength from the criteria/systems can be compared to the measured/determines rock mass strength.

  • 347.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical modelling of observed fallouts in hard rock masses using an instantaneous cohesion-softening friction-hardening model2009Ingår i: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 24, nr 4, s. 398-409Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The work presented in this paper focuses on compressive stress-induced brittle fallouts in hard rock masses, which are massive or sparsely fractured and subjected to intermediate to high in situ stresses. The results of numerical modelling, using a linear-elastic, brittle plastic material model with cohesion-softening friction-hardening (CSFH) behaviour, were compared with observed fallouts for six cases. The objective was to study how well the results of a CSFH model agrees with observed fallouts with respect to location, depth, and shape. All six cases were well documented with respect to virgin stresses, fallout characteristics, rock mass properties, and rock behaviour. The modelling results showed that shear strain localization (shear bands) developed for all cases. The depth of the intersected shear bands were used as a fallout indicator. Furthermore, the location and shape of the observed fallouts could be predicted fairly accurately. The predicted fallout depth was in good agreement with observed fallouts for three of the cases. Using both yielded elements and intersecting shear bands as fallout indicators results in a better prediction of fallout than using just one indicator.

  • 348.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Observations and modelling of failure of hard rock masses2007Ingår i: Deep Mining 07: proceedings of the fourth International Seminar on Deep and High Stress Mining, 7-9 November 2007, Perth, Australia / [ed] Yves Potvin, Perth, W.A: Australian Centre for Geomechanics, 2007, s. 81-94Konferensbidrag (Refereegranskat)
    Abstract [en]

    The objective of this paper is to run field data, without modification, for a number of case studies in different numerical models to find the best non-calibrated approach. The purpose of the comparison is to identify which frequently used approach gives the best agreement with the observed fallouts with respect to location, depth, shape, and extent. All of the five case studies are situated in hard rock masses that are massive or sparsely fractured, at depths of 630-965 m below surface. The observed fallouts are compared with the results from numerical models in Examine2D and Phase2D. None of the studied approaches give perfect agreement with the actual fallouts. This study demonstrates that when rock mass strength parameters are defined by either the Hoek-Brown or the Mohr-Coulomb criterion, the elastic and elastic-perfectly plastic models reasonably well predict actual fallout depth, although the extent of fallout is exaggerated and the shape incorrect. Therefore, a precise estimation can not be expected. When using the m=0 approach, the results were in poor agreement with the observed fallout. The fallouts are significantly overestimated when applying the brittle-plastic models using instantaneous softening by cohesion and friction or cohesion weakening.

  • 349.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Observations and modelling of fallouts of hard rock masses2007Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The objective of this paper is to apply field data, without modification, for a number of case studies in different numerical models to find the best non-calibrated approach. The purpose of the comparison is to identify which of a number of well-known and frequently used approaches to failure prediction, that gives the best agreement with the observed fallouts with respect to location, depth, shape, and extent. Four case studies are presented which all are situated in hard rock masses that are massive or sparsely fractured, at depths of 630-965 m below surface. The observed fallouts are compared with the results from five numerical models in Examine2D and Phase2D by studying (i) strength factors (SF) and yielded elements and (ii) volumetric and (iii) maximum shear strains. This study demonstrates that when the rock mass strength parameters are defined by either the Hoek-Brown or the Mohr-Coulomb criterion the predicted fallout depth by the SF and yielded elements resulted in a reasonable agreement with the observed fallout depth. Still the extent on the boundary and shape is incorrect. As a preliminary result, the volumetric strain is not found to be a good indicator of fallouts of hard (high strength) rock masses. Also, due to the high rock mass strength, no shear bands were formed when evaluating the maximum shear strain, except when using instantaneous softening of friction and/or cohesion. However the instantaneous softening approaches significantly overestimated the predicted fallouts. Despite the fact that none of the approaches in this study showed perfect agreement with the actual fallouts, a 2D stress analysis program can be used for guidance of where, on the boundary, the actual compressive fallout will occur.

  • 350.
    Edelbro, Catrin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Prediction of failure and fallouts in access drifts at the Kiirunavaara mine using numerical analysis2008Ingår i: MassMin 2008: Proceedings of the 5th International Conference and Exhibition on Mass Mining, Lulea, Sweden 9-11 June 2008 / [ed] Håkan Schunnesson; Erling Nordlund, Luleå: Luleå tekniska universitet, 2008, s. 835-844Konferensbidrag (Refereegranskat)
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