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  • 201.
    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 time2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 5, s. 482-492Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 202.
    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 Zone2017Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, nr 10, s. 848-858Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 203.
    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 Well2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 8, s. 515-524Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 204.
    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 Methods2018Inngår i: Open Petroleum Engineering Journal, ISSN 1874-8341, Vol. 11, s. 14-28Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 205.
    Elias, Issa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Area-Storage Capacity curves for Mosul Dam, Iraq Using Empirical and Semi-Empirical Approaches2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The storage capacity of reservoirs is gradually depleted due to sediment accumulation that causes changes in the area-storage capacity curves (ASC). These curves are important for planners, designers and operators of dams. Many empirical and semi-empirical approaches have been suggested for establishing and predicting these curves. In this study four empirical and semi-empirical methods were evaluated and used to determine the ASC curves for Mosul dam reservoir (MDR), which is the biggest hydraulic structure on the River Tigris in northern Iraq. MDR started operating in 1986 with a storage capacity of 11.11 km3 and a water surface area 380 km2 at normal operation stage (330 m a.s.l.). The results obtained from these methods were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam. The evaluation results showed three methods presented more accurate results for estimating water depth or sedimentation depth at dam site with percentage error about 1.06% to 3.295%.

  • 206.
    Elias, Issa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Dams and Water Resources Engineering, University of Mosul, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research, Kurdistan Region.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation and modification of some empirical and semi-empirical approaches for prediction of area-storage capacity curves in reservoirs of dams2017Inngår i: International Journal of Sediment Research, ISSN 1001-6279, Vol. 32, nr 1, s. 127-135Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The storage capacity of reservoirs is gradually reduced due to sediment accumulation that causes changes in the area-storage capacity (ASC) curves. Establishing these curves and predicting their future change is an important issue for planners, designers and operators of dams. Many empirical and semi-empirical approaches have been suggested for establishing and predicting the future changes for these curves. In this study four empirical and semi-empirical methods were evaluated and three of them were modified to be used for the prediction of changes in the ASC curves due to sedimentation, based on the existing sedimentation survey data for 11 reservoirs in the USA. For evaluation, these approaches were reviewed and used to determine sedimentation depth and establishing the ASC curves for the Mosul dam reservoir (MDR), which is the biggest hydraulic structure on the River Tigris in northern Iraq. MDR started operating in 1986 with a storage capacity of 11.11 km3 and a water surface area 380 km2 at normal operation stage (330 m a.s.l.). The results obtained from these methods were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam. The evaluation results showed three methods had presented more accurate results for estimating water depth or sedimentation depth at dam site with percentage error about 1.06–3.30%. Whilst for establishing ASC curves, one method presented good agreement result with survey data. Furthermore, ASC and sedimentation depths at dam site of MDR for periods 50, 75, 100 and 125 years were estimated using the modified approaches and the area reduction method. The results of the modified methods provided reasonable agreement when compared with the area reduction method proposed by the U.S. Bureau of Reclamation and the agreement became better with an increase in time period.

  • 207.
    Elias, Ziyad
    et al.
    Geomorphic Researcher, Celle, Germany.
    Sissakian, Varoujan
    Kurdistan University, Hewler.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    New Tectonic Activity within Zagros – Taurus belt: A case study from north Iraq using Region Shuttle Radar Topography Mission (SRTM)2018Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 8, nr 1, s. 51-63Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work investigates fold growth and drainage evolution of the Duhok – Al-Qosh and Duhkan anticlines (Iraqi Kurdistan region) by means of structural and tectonic geomorphology using a geological map and SRTM remote sensing data (digital elevation model and satellite images). The implementation of geomorphic indicator will help understanding the mechanism between growth of fold and drainage pattern and also concluding the tectonic evolution in the study site. Fault has an impact on the width of the folds and also on the drainage basin in the study area. The Aspect ratio indicates that the folds in the study area are formed by thrust-cored or forced and buckling. The tributaries of the drainage basin are characterized by drainage parallel to the fold crest on the fold hinge, with less asymmetric and asymmetric forked networks. Perfect symmetry index (FSI) is represented by Al-Qosh fold. Higher value of front sinuosity can be in the first uplift fold and later exposed to erosion by stream basin on the limbs of folds for long time. The spacing ratio and basin shape show basin maturity.

  • 208.
    Elias, Ziyad
    et al.
    Geomorphic Researcher Hannover Germany.
    Sissakian, Varoujan K.
    University of Kurdistan Hewler Iraq. Private Consultant Geologist Erbīl Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of the Tectonic Activity in Northwestern Part of the Zagros Mountains, Northeastern Iraq by Using Geomorphic Indices2019Inngår i: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529, Vol. 37, nr 5, s. 3995-4007Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Tectonic Activity of regions with active tectonics can be assessed by using of the geomorphic indices. Six Geomorphic indices including stream-gradient index (SL), drainage basin asymmetry (Af), drainage basin shape (Bs), hypsometric integral (Hi), valley floor width-valley height ratio (Vf), and mountain-front sinuosity (Smf) were calculated using GIS technique in Kifri Chai Basin; northeast Iraq, which belongs to the Western Zagros Mountain. The basin was divided into eighteen sub-basins depending on the 4th, 5th and 6th stream orders of the drainage within Kirfi Basin. It was found that the SL, Af, Bs, Hi, Vf, and Smf (J) values are uniform and exhibit almost the same classes. However, few exceptions occur, especially in Bs values, but the exceptional values do not influence significantly on the acquired results, in each of the eighteen sub-basin. From these indices the relative active tectonics index value (Iat) was determined. The results of average Iat values (2.35) showed that the tectonic activity in the whole basin is Moderate. Moreover, an attempt was carried out to compare the regional Neotectonic activity with the relative tectonic activity in the basin. The results showed that there is a positive relation between the two comparatives; especially the subsidence amount and scored relative tectonic activity.

  • 209.
    Ewaid, Salam Hussein
    et al.
    Technical Institute of Shatra, Southern Technical University, Diwaniyah, Iraq.
    Abed, Salwan Ali
    Department of Environment, College of Science, University of Al Qadisiyah, Al-Qadisiyah, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Crop Water Requirements and Irrigation Schedules for Some Major Crops in Southern Iraq2019Inngår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, nr 4, artikkel-id 756Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The climate of Iraq is of the subtropical semi-dry type; however, the country was rich in water resources until a few decades ago. Climate change and the construction of many dams on the Tigris and Euphrates rivers in the neighboring countries have caused water shortages and poor water quality. Now, there is a need to decrease consumption, improve management of water resources, and determine the water requirements of the major crops because agriculture is the first consumer of water in Iraq. The Food and Agriculture Organization (FAO) CROPWAT 8.0 simulation software and the CLIMWAT 2.0 tool attached to it have been used in this research for Dhi-Qar Province in southern Iraq to find the crop water requirements (CWRs) and irrigation schedules for some major crops. The CROPWAT Penman–Monteith method was used to calculate the reference crop evapotranspiration (ET0) and the United States Department of Agriculture (USDA) soil conservation (S.C.) method was used to estimate the effective rainfall. The study results showed that ET0 varied from 2.18 to 10.5 mm/day and the effective rainfall varied from 0.0 to 23.1 mm. The irrigation requirements were 1142, 203.2, 844.8, and 1180 mm/dec for wheat, barley, white corn, and tomatoes, respectively. There is a higher water demand for crops during the dry seasons (summer and autumn) and a lower demand during the wet seasons (winter and spring). The total gross irrigation and the total net irrigation were 343.8 mm and 240.7 mm for wheat, 175.2 mm and 122.6 mm for barley, 343.8 mm and 240.7 mm for white corn, and 203.3 mm and 142.3 mm for tomatoes. This study proved that the CROPWAT model is useful for calculating the crop irrigation needs for the proper management of water resources.

  • 210.
    Ewaid, Salam Hussein
    et al.
    Technical Institute of Shatra, Southern Technical University, Al-Qadisiyah, Iraq.
    Abed, Salwan Ali
    Department of Environment, College of Science, University of Al-Qadisiyah, Al-Qadisiyah, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Water Footprint of Wheat in Iraq2019Inngår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, nr 3, artikkel-id 535Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The water footprint (WF) is an indicator of indirect and direct fresh water use. In respect of

    facilitating decision-making processes,WF gives an excellent perspective on how and where fresh water is used in the supply chain. More than 39million people live in Iraq and,with a growing population, there is a water shortage and a rising demand for food that cannot be met in the future. In this study, theWF of wheat production is estimated for the year 2016–2017 for 15 Iraqi provinces. TheWF was calculated using the method ofMekonnen and Hoekstra (2011) and the CROPWAT and CLIMWAT softwares’ crop water requirement option. It was found that theWF in m 3/ton was 1876 m3/ton. The 15 provinces showed variations inWFs, which can be ascribed to the difference in climate and production values. The highest

    wheat WF was found in Nineveh province, followed by Muthanna, Anbar, and Basra. The last three provinces produce little and have a highWF so, in these provinces, wheat can be replaced with crops that need less water and provide more economic benefit. There is an opportunity to reduce the greenWF by increasing production from the 4 rain-fed provinces, which will reduce the need for production from the irrigated provinces and, therefore, reduce the use of blue water.

  • 211.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of SWAT Model to Estimate the Runoff and Sediment Load from the Right Bank Valleys of Mosul Dam Reservoir2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Mosul Dam is the biggest hydraulic structure on the River Tigris in Iraq with 11.11 billion m3 storage capacity. The dam is a multipurpose project. It is used to store the water for irrigation, hydropower generation, and flood control. As in other dams in the world, this dam also have sedimentation problem. Sediment accumulation in its reservoir can effect the dam operation (pumping station, hydropower plants, and bottom outlets) and it will definitely shorten the life span of the dam. In this study, the Soil and Water Assessment Tool (SWAT) under Geographical Information System (GIS) was applied to simulate the yearly surface runoff and sediment load for the main three valleys on the right bank of Mosul Dam Reservoir. The simulation considered for the twenty one years begin from the dam operation in 1988 to 2008. The resultant values of the average annual sediment load are 35.6*103, 4.9*103, and 2.2*103 ton, while the average values of sediment concentration are 1.73, 1.65, and 2.73 kg/m3 for the considered valleys one, two and three respectively. This implies that significant sediment load enters the reservoir from these valleys. To minimize the sediment load entering the reservoir, a check dams is to be constructed in suitable sites especially for valley one. The check dam can store the runoff water and trap the sediment load, and then the flow can be released to the reservoir.

  • 212.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Estimating life span of rainwater harvesting reservoirs in Sinjar area, Iraq2016Inngår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, s. 1-10, artikkel-id 9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Due to water shortage in different places in Iraq especially for areas far away from main river flows (Tigris and Euphrates Rivers), rainwater harvesting reservoirs were suggested previously to store runoff water for different water supply purposes. In this study, the Soil and Water Assessment Tool (SWAT) was applied to estimate the sediment load yields from each watershed of a selected reservoir to estimate probable life based on resultant sediment load and trap efficiency. The results indicates that the annual sediment load varied from 40*103 to 4.4*103 ton depending on watershed area and other effective properties, while the sediment yield per unit area were ranged between 9.5 to 20 ton/km2. The estimated trap efficiency based on annual inflow and reservoir storage capacity were varied from a minimum of 96.5 to 100% due to high reservoir capacity in comparison to annual inflow. The resultant probable life of the reservoirs was greater than 100 years, indicating that the reservoir can economically accepted.

  • 213.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Runoff and sediment load from the right bank valleys of Mosul dam reservoir2012Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 6, nr 10, s. 1414-1419Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul Dam is a Multipurpose Project on the River Tigris in Iraq with 11.11 billion m3 storage capacity.. It is used to store the water for irrigation, hydropower generation, and flood control. As in other dams in the world, this dam also have sedimentation problem. Sediment accumulation in its reservoir can effect the dam operation (pumping station, hydropower plants, and bottom outlets) and it will definitely shorten the life span of the dam. In this study, the SWAT (soil and water assessment tool) under GIS (Geographical Information System) was applied to simulate the yearly surface runoff and sediment load for the main three valleys on the right bank of Mosul Dam Reservoir. The simulation considered for the twenty one years begin from the dam operation in 1988 to 2008. The resultant values of the average annual sediment load are 35.6x103, 4.9x103, and 2.2x103 ton, while the average values of sediment concentration are 1.73, 1.65, and 2.73 kg/m3 for the considered valleys one, two and three respectively. This implies that significant sediment load enters the reservoir from these valleys. To minimize the sediment load entering the reservoir, a check dam is to be constructed in suitable sites especially for valley one. The check dam can store the runoff water and trap the sediment load, and then the flow can be released to the reservoir.

  • 214.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sediment delivery from right bank valleys to Mosul reservoir, Iraq2012Inngår i: Journal of Ecology and Environmental Sciences / Bioinfo publications, ISSN 0976-9900, E-ISSN 0976-9919, Vol. 3, nr 1, s. 50-53Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam reservoir is the biggest reservoir on the River Tigris with 11.11 billion m3 storage capacity located at the northern part of Iraq. The dam is used for irrigation, hydropower generationand flood control. Siltation of the reservoir and sediment delivery from the valleys to the reservoir was not measured since the operation of the dam in 1988. Sediment accumulation in its reservoir can effect the dam operation (pumping station, hydropower plantsand bottom outlets) and it will definitely shorten the life span of the dam. In this study, the Soil and Water Assessment Tool (SWAT) under Geographical Information System (GIS) was applied to simulate the yearly surface runoff and sediment load for the main three valleys on the right bank of Mosul am Reservoir for the period 1988-2008. The resultant values of the average annual sediment load are 42.7*103, ton. This implies that significant sediment load enters the reservoir from these valleys. Sediment accumulation can effect the dam operation (pumping station, hydropower plants and bottom outlets) and it will definitely shorten the life span of the dam. To minimize sediment effect, check dams are to be constructed specially on the first valley.

  • 215.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hassan, Rebwar
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Ammar
    Department of Water Resources Engineering, Baghdad Universi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Watershed Sediment and Its Effect on Storage Capacity: Case Study of Dokan Dam Reservoir2018Inngår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, nr 7, artikkel-id 858Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dokan is a multipurpose dam located on the Lesser Zab River in the Iraq/Kurdistan region. The dam has operated since 1959, and it drains an area of 11,690 km2. All reservoirs in the world suffer from sediment deposition. It is one of the main problems for reservoir life sustainability. Sustainable reservoir sediment-management practices enable the reservoir to function for a longer period of time by reducing reservoir sedimentation. This study aims to assess the annual runoff and sediment loads of the Dokan Dam watershed using the soil and water assessment tool (SWAT) model to evaluate the relative contributions in comparison with the total values delivered from both watershed and Lesser Zab River and to identify the basins with a high sediment load per unit area. These help in the process of developing a plan and strategy to manage sediment inflow and deposition. The SUFI-2 program was applied for a model calibrated based on the available field measurements of the adjacent Derbendekhan Dam watershed, which has similar geological formations, characteristics and weather. For the calibration period (1961–1968), the considered statistical criteria of determination coefficients and Nash–Sutcliffe model efficiency were 0.75 and 0.64 for runoff while the coefficients were 0.65 and 0.63 for sediment load, respectively. The regionalization technique for parameter transformation from Derbendekhan to Dokan watershed was applied. Furthermore, the model was validated based on transformed parameters and the available observed flow at the Dokan watershed for the period (1961–1964); they gave reasonable results for the determination coefficients and Nash–Sutcliffe model efficiency, which were 0.68 and 0.64, respectively. The results of SWAT project simulation for Dokan watershed for the period (1959–2014) indicated that the average annual runoff volume which entered the reservoir was about 2100 million cubic meters (MCM). The total sediment delivered to the reservoir was about 72 MCM over the 56 years of dam life, which is equivalent to 10% of the reservoir dead storage. Two regression formulas were presented to correlate the annual runoff volume and sediment load with annual rain depth for the studied area. In addition, a spatial distribution of average annual sediment load was constructed to identify the sub basin of the high contribution of sediment load.

  • 216.
    Fikrat, Hassan
    et al.
    University of Baghdad.
    Salman, Jasim
    Babylon University.
    Al-Azawey, Atheer
    Babylon University.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Quatlity, quantity and origin of polycyclic aromatic hydrocarbons (PAHs) in lotic ecosystem of AL-Hilla river, Iraq2014Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 8, nr 8, s. 1026-1038Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The quality, quantity and the origin of Poly Aromatic Hydrocarbon (PAHs) were studied in the water and sediment of Al-Hilla river (branch of the Euphrates river inside Iraq). In addition, some physical and chemical properties were studied at six sites along the studied area, for the period March, 2010 to February, 2011. Sixteen Polycyclic Aromatic Hydrocarbons (PAHs) that are listed by USEPA as priority pollutants ( Naphthalene, Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene, Anthracene, Fluoranthene, Pyrene, Benzo(a)Anthracene, Chrysene, Benzo(b) Fluoranthene, Benzo(k) Fluoranthene, Benzo(a) Pyrene, Dibenzo(a,h) Anthracene, Benzo(ghi) Perylene and Indeno (1,2,3-cd) Pyrene) were detected in Al-Hilla river. High concentrations of PAHs were detected in the sediment relative to that within the water. The present study revealed that the origin of PAHs in water and sediment might be the Pyrogenic origin.

  • 217.
    Hadi, Sinan Jasim
    et al.
    Department of the Real Estate Development and Management, Ankara University, Ankara, Turkey.
    Abba, S.I.
    Department of Physical Planning Development, Maitama Sule University Kano, Nigeria.
    Sammen, Saad Sh.
    Department of Civil Engineering, College of Engineering, University of Diyala, Diyala Governorate, Iraq.
    Salih, Sinan Q.
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Non-linear input variable selection approach integrated with non-tuned data intelligence model for streamflow pattern simulation2019Inngår i: IEEE Access, E-ISSN 2169-3536, Vol. 7, s. 141533-141548Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Streamflow modeling is considered as an essential component for water resources planning and management. There are numerous challenges related to streamflow prediction that are facing water resources engineers. These challenges due to the complex processes associated with several natural variables such as non-stationarity, non-linearity, and randomness. In this study, a new model is proposed to predict long-term streamflow. Several lags that cover several years are abstracted using the potential of Extreme Gradient Boosting (XGB) then after the selected inputs variables are imposed into the predictive model (i.e., Extreme Learning Machine (ELM)). The proposed model is compared with the stand-alone schema in which the optimum lags of the variables are supplied into the XGB and ELM models. Hydrological variables including rainfall, temperature and evapotranspiration are used to build the model and predict the streamflow at Goksu-Himmeti basin in Turkey. The results showed that XGB model performed an excellent result in which can be used for predicting the streamflow pattern. Also, it is clear from the attained results that the accuracy of the streamflow prediction using XGB technique could be improved when the high number of lags was used. However, the implementation of the XGB is tree-based technique in which several issues could be raised such as overfitting problem. The proposed schema XGBELM in which XGB approach is selected the correlated inputs and ranking them according to their importance; then after, the selected inputs are supplied into the ELM model for the prediction process. The XGBELM model outperformed the stand-alone schema of both XGB and ELM models and the high-lagged schema of the XGB. It is important to indicate that the XGBELM model found to improve the prediction ability with minimum variables number.

  • 218.
    Hashim, Bassim Mohammed
    et al.
    Ministry of Science and Technology, AL Mustansiriyah University, Baghdad, Iraq.
    Sultan, Maitham Abdullah
    Ministry of Science and Technology, AL Mustansiriyah University, Baghdad, Iraq.
    Attyia, Mazin Najem
    Iraqi Atomic Energy Commission, Baghdad, Iraq.
    Al Maliki, Ali A.
    Ministry of Science and Technology, AL Mustansiriyah University, Baghdad, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Change Detection and Impact of Climate Changes to Iraqi Southern Marshes Using Landsat 2 MSS, Landsat 8 OLI and Sentinel 2 MSI Data and GIS Applications2019Inngår i: Applied Sciences, E-ISSN 2076-3417, Vol. 9, nr 10, artikkel-id 2016Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Marshes represent a unique ecosystem covering a large area of southern Iraq. In a major environmental disaster, the marshes of Iraq were drained, especially during the 1990s. Since then, droughts and the decrease in water imports from the Tigris and Euphrates rivers from Turkey and Iran have prevented them from regaining their former extent. The aim of this research is to extract the values of the normalized dierence vegetation index (NDVI) for the period 1977–2017 from Landsat 2 MSS (multispectral scanner), Landsat 8 OLI (operational land imager) and Sentinel 2 MSI (multi-spectral imaging mission) satellite images and use supervised classification to quantify land and water cover change. The results from the two satellites (Landsat 2 and Landsat 8) are compared with Sentinel 2 to determine the best tool for detecting changes in land and water cover. We also assess the potential impacts of climate change through the study of the annual average maximum temperature and recipitation in dierent areas in the marshes for the period 1981–2016. The NDVI analysis and image classification showed the degradation of vegetation and water bodies in the marshes, as vast areas of natural vegetation and agricultural lands disappeared and were replaced with barren areas. The marshes were influenced by climatic change, including rising emperature and the diminishing amount of precipitation during 1981–2016.

  • 219.
    Hassan, Rebwar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Ammar A.
    College of Engineering, University of Baghdad, Baghdad, Iraq.
    Ali, Salahalddin S.
    Department of Geology, University of Sulaimani, Sulaymaniyah, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Bathymetry and siltation rate for Dokan Reservoir, Iraq2017Inngår i: Lakes & Reservoirs: Research and Management, ISSN 1320-5331, E-ISSN 1440-1770, Vol. 22, nr 2, s. 179-189Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Dokan Reservoir dam is a concrete cylindrical arch with gravity abutments, located on the Lesser Zab River about 60 km from the city of Sulaimani in north-eastern Iraq. A bathymetric survey was conducted in November 2014 for a period of 10 days, using an echo sounder of 200-kHz single beam. The survey results indicated an annual average sediment deposition of 3.8 million m3. Thirty-two sediment samples were collected from the reservoir bed. The ratio of gravel, sand, silt and clay was 15:14:48:23, respectively. The reservoir bed is covered mainly with silt. The sediments are composed of silty clay (77.6%), silty sandy clay (10%), sandy gravely silty clay (1.2%) and gravely sandy silty clay (1%).

  • 220.
    Hassan, Rebwar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Salahaddin S.
    Department of Geology, University of Sulaimani, Sulaymaniyah, Iraq.
    Ali, Ammar A.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Abdullah, Twana
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dukan Dam Reservoir Bed Sediment, Kurdistan Region, Iraq2016Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 9, s. 582-596Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Dukan Dam Reservoir (DDR) in the Kurdistan Region of Iraq has been studiedto determine the characteristics and nature of the reservoir and the deposited sedimentson its bottom surface. This study was achieved by doing a field survey andgrain size analyses of the collected sediment samples at 32 locations representing thewhole reservoir area that had been created when the Lesser Zab River was dammedin 1959. The Dukan Dam, which is a multi-purpose concrete arch dam, was built onthe Lesser Zab River for controlling its flood during high rainfall seasons, irrigationand power generation. The catchment area is 11,690 km2. The surface area of the reservoiris 270 square kilometers and the volume is 6.870 × 106 m3 at normal operationlevel (El. 511.00 m. a.s.l.). The minimum drawdown level is at elevation 469 mabove sea level (a.s.l.). The live storage is 6.14 × 106 m3 while the remainder is deadstorage. The reservoir has a surface area that reaches 270 square kilometers and iscomposed of two sub-reservoirs connected by a narrow channel that has a length of 5kilometers. The relatively bigger reservoir is located in the north and has a triangularshape with a surface area approximately 250 square kilometers. The smaller sub-reservoiris located down south where the dam exists and it has irregular rectangularshape. Thirty-two sediment samples were collected from the bottom of Dukan reservoir.The bed of the reservoir is mainly composed of 15% gravel, 14% sand, 48%silt and 23% clay respectively. Most of the sediments are very fine grained, verypoorly sorted, strongly coarse skewed and mesokurtic.

  • 221.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Enhancement of Workability of Cement-Poor Concrete by Optimizing Paste Content2014Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 6, nr 13, s. 869-876, artikkel-id 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study describes the performance of concrete in fresh state, intended for sealing deep boreholes in the host rock of radioactive repositories. Set of different paste volumes, combinations of water-to-powder ratios and fine aggregate contents have been performed within the frame of this study. The main objective was to search for tendencies, logical connections and phenomena that occur for different combination of materials regarding the fluidity and segregation and mainly the effect from the (paste) or fine aggregate content. It shall be pointed out that this investigation is a suggestion on how concrete can be optimized using two simple test methods based on changing the paste content. The results highlighted the importance of having sufficient amounts of filler and cement paste for separate and carry larger particles, which gives the concrete good workability and fluidity at casting. It was concluded that the slump behaviors can be optimized based on the adjustments of the superplastisizer dosage.

  • 222.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Rheological properties of low pH cement-palygorskite injection grout2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 3, s. 167-192Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The rheological properties of cementitious materials containing fine particles, such as mineral admixture were investigated using a Viso Star-L rheometer with cylindrical spindles. Selected features of the behavior of these materials are evaluated from a rheological perspective through literatures results for the past 30 years. One of the important factors that governs the ability of grout to penetrate fractures, channels and porous material is the rheology. The mineral admixture was clay palygorskite which can be used for early gelation because of its thixotropic properties as well as the powder quartz used as aggregate. The cementitious materials were designed and three recipes (MPG1, MPG2 and MPG3) were examined in this research by changing the mix proportions of the mineral admixture palygorskite and water content. For ensuring the accuracy of rheological measurement for the candidate’s grouts, necessary verification was been evaluated such as, influence of mixing time, stability and “time effect” to the accuracy of viscosity measurement, and yield stress as well as the physical properties at 3, 7 and 28 days. The results showed that grouts recipes with quartzite aggregate of different granulometry, are chemically compatible and fulfill the requirement of containing no organic matter. Candidate’s grouts found to satisfy the stable sedimentation criteria with sedimentation rates less than 5% after 2 hours. Furthermore, it was found that the grout recipe 3 followed by 1 showed lower yield stress and plastic viscosity which are (0.1 Pa and 0.269 Pas) and (0.288 Pa and 0.531 Pas) respectively.

  • 223.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Gburi, Majid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Design of concrete mixes by systematic steps and ANN2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 4, s. 232-251Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The current research caters for the possibility of arriving at a system for designing concrete mixeseasily using available materials locally by specified wide ranges of pre-requisites of three mainprescribed properties to cover a good variety of practical mixes, which are water, water-cement ratioand total aggregate-cement ratio. Using these three properties, a tri-linear form was constructed bygraphical technique manner based on absolute volume approach. This approach defines as asummation of absolute volume for each of these three materials individually water, cement andaggregate should be equal to the absolute volume of whole concrete mixture based on thesealtogether. A quad-form area which includes a wide range of mixes can be formed from thisrepresentation. This area should achieve all the prescribed properties aforementioned. Artificial neuralnetwork concept used in this study also to build easily and quickly system which can be translatedinto Excel sheet. This system predict proportions of concrete mixture and the compressive strengthusing the results designed by the quad-form area method in addition to the data from literature around500 mixes based on local materials used in Iraq. Six input parameters (water to cement ratio, theslump, % of fine to total aggregate content, maximum aggregate size, fineness modulus of fineaggregate and the compressive strength) were used in this system to get the outputs. In addition, nineinput parameters ((water, cement, sand and gravel contents) and the properties of the mix (Finenessmodulus, W/C ratio, the slump, % of fine to total aggregate and the M.A.S)) were used as basis ofcompressive strength model. The algorithm of this system aimed to reduce the high number of trailmixes error as well as saving the labors, cost and time. Results indicated that the concrete mix designand the compressive strength model can be predicted accurately by using graphical perspective andthe ANN approach.

  • 224.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Optimization of concrete by minimizing void volume in aggregate mixture system2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 3, s. 208-222Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The behavior of concrete is affected by the size, distribution of the voids, the porosity and of the granulometry of the aggregate mixture. As a consequence it necessary for engineers to consider in detail particle packing concepts and their influence on the physical performance of concrete. The present study included determination of the fineness modulus, cement paste volume based on slump test and the properties of fresh and hardened concrete. It also comprised a study of the applicability of two theoretical models Toufar’s and 4C-packing program for selecting suitable relative amounts of the concrete constituents, for obtaining a minimum void ratio. Comparison of the results was made from using these theoretical models literature-derived experimental data. The models gave similar results and suggest similar combinations of materials to give minimum void ratio. Optimization of the composition of the aggregate material in concrete is beneficial with respect to economy (low cement content), strength and durability. It was noted that minimizing the void ratio (V) tends to raise the stiffness and that the compressive strength (푓푐′) is closely related also to their molding (R) and fineness modules (FM). It was found that the compressive strength can be predicted by applying the formula;푓푐′=−2.1−63.8 푉+0.150 푅+10.4 퐹푀; R2=0.94, and two other relationships related to slump data and cement content.

  • 225.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilsson, Martin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Alireza, Pourbakhtiar
    Talc-based concrete for sealing borehole optimized by using particle packing theory2013Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 7, nr 4, s. 440-455Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper describes assessment of the performance of cement-poor concreteson the basis of packing theory. The concretes are intended for sealing segments of deep boreholes and have a small amount of cement for minimizing the mutual chemical impact on the contacting clay seals. The composition is examined by application of packing theory with respect to the cement/aggregate ratio and the gradation of the aggregate material which is crushed quartzite for providing high internal friction after maturation, as well as to talc added for fluidity and to the small amount of cement. Low porosity and micro-structural stability must be guaranteed for very long periods of time. The study exemplifies how packing theory assist designers in selecting optimal proportions of the various components. Optimum particle packing implies minimizing the porosity and thereby reducing the amount of cement paste needed to fill the voids between the aggregate particles. The use of talc as inorganic super-plasticizer since ordinary organic additives for reaching high fluidity at casting are undesirable, and since talc reacts with cement and provides high strength in along-term perspective.

  • 226.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pourbakhtiar, Alireza
    Proportioning of cement-based grout for sealing fractured rock-use of packing models2013Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 10, s. 765-774Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fractured, very permeable rock hosting repositories for radioactive waste will require grouting. New grout types of possible use where long-term performance is needed should have a small amount of cement for minimizing the increase in porosity that will follow from the ultimate dissolution and erosion of this component. They have to be low-viscous and gain strength early after injection and packing theory can assist designers in selecting suitable proportions of various grout components. Optimum particle packing means that the porosity is at minimum and that the amount of cement paste needed to fill the voids between aggregate particles is very small. Low porosity and microstructural stability must be guaranteed for long periods of time. Organic additives for reaching high fluidity cannot be used since they can give off colloids that carry released radionuclides and talc can be an alternative superplasticizer. Low-pH cement reacts with talc to give high strength with time while Portland cement gives early but limited strengthening. The clay mineral palygorskite can be used for early gelation because of its thixotropic properties. Once forced into the rock fractures or channels in soil it stiffens and serves as a filter that prevents fine particles to migrate through it be lost. However, its hydrophilic potential is too high to give the grout a high density and high strength. According to the experiments carried out most of the investigated grouts are injectable in fractures with apertures down to 100 μm.

  • 227.
    Hilo, Ali Nasser
    et al.
    Civil Engineering Department, Wasit University, Kut, Iraq.
    Saeed, Fouad Hussein
    Ministry of Water Resources, Kut, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Impact of Climate Change on Water Resources of Dokan Dam Watershed2019Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 8, s. 464-474Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lesser Zab is one of the most important tributaries of Tigris River. During the last few decades, the streamflow significantly decreased for long periods followed by extensive flood in short periods. This study aimed to quantify the impact of climate change on streamflow at Dokan Dam until year 2050 using SWAT model based on the scenario of medium emission (A1B) and five climate projection models. SWAT run using Climate Forecasting System Reanalysis (CFSR) was used as weather input data then calibrated and validated on monthly time step for the period from 1980 to 2013 with Nash-Sutcliff Ef- ficiency (NSE) of 0.73 and determination coefficient (R2) 0.73 for calibration processes. The data of this period is more reliable. The result indicated to a significant decrease on the projected streamflow until year 2050 with average streamflow for the six climate models of 167 m3/sec in past compared with the observed streamflow of 176.5 m3/sec for the base period (1980-2013). In addition,  the  study  shows  that most runoffs come  from Iranian  part of  the Dokan Dam Watershed with 65% of total simulated runoff. It is highly recommended  to  improve  the  efficiency  of  water  using  for  current  and  future water projects to meet the expected water shortage.

  • 228.
    Homsi, Rajab
    et al.
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Shiru, Mohammed Sanusi
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia. Department of Environmental Sciences, Faculty of Science, Federal University Dutse, Dutse, Nigeria.
    Shahid, Shamsuddin
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Ismail, Tarmizi
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Harun, Sobri Bin
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, Peoples People’s Republic of China.
    Yaseen, Zaher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Precipitation projection using a CMIP5 GCM ensemble model: a regional investigation of Syria2020Inngår i: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 14, nr 1, s. 90-106Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The possible changes in precipitation of Syrian due to climate change are projected in this study. The symmetrical uncertainty (SU) and multi-criteria decision-analysis (MCDA) methods are used to identify the best general circulation models (GCMs) for precipitation projections. The effectiveness of four bias correction methods, linear scaling (LS), power transformation (PT), general quantile mapping (GEQM), and gamma quantile mapping (GAQM) is assessed in downscaling GCM simulated precipitation. A random forest (RF) model is performed to generate the multi model ensemble (MME) of precipitation projections for four representative concentration pathways (RCPs) 2.6, 4.5, 6.0, and 8.5. The results showed that the best suited GCMs for climate projection of Syria are HadGEM2-AO, CSIRO-Mk3-6-0, NorESM1-M, and CESM1-CAM5. The LS demonstrated the highest capability for precipitation downscaling. Annual changes in precipitation is projected to decrease by −30 to −85.2% for RCPs 4.5, 6.0, and 8.5, while by < 0.0 to −30% for RCP 2.6. The precipitation is projected to decrease in the entire country for RCP 6.0, while increase in some parts for other RCPs during wet season. The dry season of precipitation is simulated to decrease by −12 to −93%, which indicated a drier climate for the country in the future.

  • 229.
    Hou, Muzhou
    et al.
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Zhang, Tianle
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Weng, Futian
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Ali, Mumtaz
    School of Agricultural, Computational and Environmental Sciences Institute of Agriculture and Environment, University of Southern Queensland, Springfield, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Global Solar Radiation Prediction Using Hybrid Online Sequential Extreme Learning Machine Model2018Inngår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, nr 12, artikkel-id 3415Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Accurate global solar radiation prediction is highly essential for related research on renewable energy sources. The cost implication and measurement expertise of global solar radiation

    emphasize that intelligence prediction models need to be applied. On the basis of long-term measured daily solar radiation data, this study uses a novel regularized online sequential extreme learning machine, integrated with variable forgetting factor (FOS-ELM), to predict global solar radiation at Bur Dedougou, in the Burkina Faso region. Bayesian Information Criterion (BIC) is applied to build the seven input combinations based on speed (Wspeed), maximum and minimum temperature (Tmax and Tmin), maximum and minimum humidity (Hmax and Hmin), evaporation (Eo) and vapor pressure deficiency (VPD). For the difference input parameters magnitudes, seven models were developed and evaluated for the optimal input combination. Various statistical indicators were computed for the prediction accuracy examination. The experimental results of the applied FOS-ELM model demonstrated a reliable prediction accuracy against the classical extreme learning machine (ELM) model for daily global solar radiation simulation. In fact, compared to classical ELM, the FOS-ELM model reported an enhancement in the root mean square error (RMSE) and mean absolute error(MAE) by (68.8–79.8%). In summary, the results clearly confirm the effectiveness of the FOS-ELM model, owing to the fixed internal tuning parameters.

  • 230.
    Huang, Yi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The one dimensional model for coarse particle around mining area in northern Sweden2012Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 2, s. 126-137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Computational model had been established to predict the coarse dust transport rate within the Malmberget mining area in northern Sweden. Matlab GUI designing had been introduced to enhance the computation process. Certain modification methods were developed in order to improve the accuracy of the model. Dust retention time was calculated to estimate the dust transport in the suspension form. Field calibration proves the code works fairly well for the coarse dust in the research area.

  • 231.
    Huang, Yi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The simulation of the dust grain movement by sediment transport model around mining area in northern Sweden2012Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 1-11Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A simple sediment transport model has been utilized to simulate the dust grain movement in the area flow. The transport model can be used as a tool to estimate the dust grain transport situation in a mining area with consideration of the local topographical profile. The case study of the local dust characteristics survey proves the model works fairly well compared to the field calibration.

  • 232.
    Huda M., Madhloom
    et al.
    Mustansiriayah University, Baghdad- Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Geographical Information System and Remote Sensing for WaterResources Management Case Study: The Diyala River, Iraq2018Inngår i: International J. of Civil Engineering and Technology, ISSN 0976-6308, Vol. 9, nr 12, s. 971-984Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Utilizing Geographical Information System (GIS) in the management of water resources, especially, in the quality of surface water, constiytutes a worthwile attempt made in the improvement and control the levels of pollution in the water. In this paper, GIS technology was used in conjunction with Water Quality Index (WQI) to assess the suitability for onsumption of water in the souther within Baghdad City for human needs based on the set of monthly measurements during the period from January to December 2016. The variables measured in seven monitoring stations along the studied reach of the river were: Total Di

    (T.D.S), Total Hardness (T.H), Sulphate ion (SO Biochemical Oxygen Demand (BODhigher than the permissible limits specified by Iraqi and WHO regulations for the dand wet seasons. The digital pollution maps showed that the pollution moved from extremely polluted zones near the outfalls of wastewater to low polluted zones near the confluence of the Diyala and Tigris techniques are among the most effective methods to display the seasonal variability on

    water quality, which can be used by the decision makers.

  • 233.
    Hussain, Hussain M.
    et al.
    Department of Geology, Faculty of Science, University of Kufa.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Groundwater Pollution Potential in Part of the Western Desert, Iraq2015Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, nr 1, s. 1-17Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The growth of human population often corresponds with change in land use, including expansion of urban areas, which necessitates increasing the available amount of drinking water. As the surface water sources are more amenable to pollution, it has become necessary to use groundwater at an increasing rate. Groundwater is normally abundant in the alluvial region where the urban areas are often located. Such areas face a greater risk of pollution of groundwater due to several factors. Surface water resources are becoming more scares in Iraq which gave a tendency to use groundwater. In this research, groundwater vulnerability in part of the western desert had been studied. It was noticed that the area has low risk for the contamination of ground water.

  • 234.
    Hussain, Hussain Musa
    et al.
    Department of Geology, Faculty of Science, University of Kufa.
    Al-Haidarey, Mohammed
    Department of Ecology, Faculty of Science, University of Kufa.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation and Mapping Groundwater Suitability for Irrigation Using GIS in Najaf Governorate, Iraq2014Inngår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 22, artikkel-id 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Irrigation Water Quality Index (IWQI) for groundwater within the Geographic Information System(GIS) environment is proposed so that it can be used in assessing the groundwater vulnerability. Themodel was applied to the Damman aquifer in the western part of Iraq. Thirty nine sites were chosen forthe investigation of the Damman aquifer. Triplicate ground water samples were collected from eachsite (during wet and dry seasons of 2013). Variables tested in each sample include: pH, EC, totalhardness Ca+2, Mg+2, Cl-, Na+ and SAR. The final water quality map constructed for the aquifershowed that there are three major regions. The first is in the northeastern part of the area while thesecond region is confined to the southeastern part. Finally, the third region extended along the westernpart of the study area. When this map was converted according to the suggested model, it showed thatthe water quality of the Damman aquifer is marginal for use for agriculture purposes.Journal

  • 235.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Experimental Analysis of Sediment Deposition Due to Backwater Effect up-stream a Reservoir2014Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 8, nr 9, s. 1185-1193Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The phenomenon of aggradation due to sediment accumulation upstream reservoirs had been studied in this research. For this purpose, group of experiments were conducted in a laboratory channel 25 m long, 0.80 m wide and 0.70 m deep. A block was built at the end of the channel to work as a dam to impound water. The channel was supplied with drainage pipes on both sides to release water out in a manner similar to what happens in reservoirs. The bed of the channel was filled with sand of 0.80 mm median sieve diameter and 0.72 geometric standard deviation. The slope was 0.0093 for all experiments. Two sizes of sand were used representing the sediment. The median diameter and geometric standard deviation of the first were 0.365 mm and 0.46 respectively. The second sample had 0.65 mm median diameter and 0.67 standard deviation. A total of seventy experiments were conducted in two groups to examine effect the sediment transport rate, particle size of sediment and flow velocity on aggradation characteristics. The results showed that there is a strong linear direct relationship between aggradation elements (length and depth) with the rate of sediment transport. Group of dimensionless parameters affecting the aggradation characteristics were used to develop empirical equations to predict the length, maximum depth of aggradation and predict transient bed profile. The results of empirical approach were compared with the measurement data and previous numerical method. The results indicated that the percentage error was –19 to 31% for length of aggradation and –21 to 26% for maximum depth of aggradation. The results also showed that the sediment material were deposited closer to the body of the dam when the released water from the dam is higher than the inflow.

  • 236.
    Issa, Issa E
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Sedimentation Characteristics and Capacity Curve for Mosul Dam Reservoir, Iraq2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The sedimentation process is the most important problems that affect directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic assessment of the storage capacity and determining sediment deposition patterns is an important issue for operation and management of reservoirs. In this study, bathymetric survey results had been used to assess the characteristics of sedimentation of Mosul Reservoir. It is located on the Tigris River in the north of Iraq. The water surface area of its reservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330 m a.s.l). The dam started operating in 1986. No detailed study was yet carried out to assess its reservoir. The present study indicated that the annual sediment deposited in the reservoir is 45.72 × 106 m3year-1 which is divided into 23.2 × 106 and 22.52 × 106 m3year-1 for dead and live zones respectively. This implies the annual reduction rate in the dead and live storage capacities of the reservoir is 0.786% and 0.276% respectively. Furthermore, the stage-storage capacity curves for the future periods (prediction curves) were assessed using 2011 bathymetric survey data.

  • 237.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment sedimentation rate in the Mosul dam reservoir, Iraq2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq that was built on the Tigris River 60 km north-west Mosul city north of Iraq. The water surface area of its reservoir is 380 km2 with a storage capacity of 11.11×109 m3 at a maximum operation level (330 m.a.s.l). The dam became operational in 1986. No study has been conducted to determine the sedimentation rate, storage capacity and new operational curve since that date. To develop an up to date operational curve, a new bathymetric survey was conducted in 2011. The results indicated that the reduction in the storage capacity of the reservoir was 10.29 %. This implies that the annual sedimentation rate within the reservoir was 45.72×106 m3.yr-1 (0.41%) that is less than the average worldwide rate. Consequently, a new operational curve was constructed.

  • 238.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Changes in bed morphology of Mosul dam reservoir2013Inngår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 2, s. 86-95Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq. It was constructed on the Tigris River in the north of Iraq for multiple purposes: irrigation, flood control and power generation. The initial storage capacity and water surface area of its reservoir reach 11.11 km3 and 380 km2 respectively at the maximum operation level 330 m.a.s.l. The dam was operated in 1986. Since that time no survey has been conducted to determining the characteristics of sedimentation in the reservoir. Blockage of the intakes of the pump station for North Al-Jazira Irrigation Project in Mosul dam reservoir has highlighted the importance of sedimentation problems within the reservoir.Sediment distribution was studied within the reservoir. A comparison was made between the conditions at the start of the dam operation and a recent bathymetric survey conducted in 2011.The former was achieved using a topographic map scale 1: 50000 dated 1983 which was converted to a triangular irregular network (TIN) format using the Arc/GIS program. The results of the bathymetric survey were also converted to the TIN map format using the above program. Comparison of the two maps shows that the sedimentation magnitude in the upper zone of the reservoir, where the River Tigris enters, was highest and gradually reduced toward Mosul dam site. Maximum deposition thickness within the reservoir was 17.6 m. The thalweg bed slope of the River Tigris within reservoir area changed from 0.65 m.km-1 before dam construction to 0.71 m.km-1 on the 2011 survey. Zones within the

  • 239.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mosul Dam Resorvoir Sedimentation Characteristics, Iraq2014Inngår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 22, artikkel-id 3Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sediment transported by rivers and finally deposited in reservoirs directly affects dam performanceand causes a reduction in their storage capacity and hence operating efficiency. In this study, thesedimentation characteristics of Mosul dam reservoir have been evaluated using two topographic mapsof the reservoir area at different times (1986 and 2011) via Arc/GIS software. The dam is located on theTigris River in the northern part of Iraq and started operating in 1986. The water surface area of itsreservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330m a.s.l). The results showed that the annual sediment deposition rate is 45.72 × 106 m3 year-1 of which23.2 × 106 and 22.52 × 106 m3 year-1 are in the dead storage and live storage zones respectively. As aconsequence, the live and dead storage zones lost 6.9% and 19.66% respectively of their storagecapacity during the 25 year of operation of the dam. The water-spread area (water surface area) of thereservoir at dead storage level (300 m a.s.l) was reduced annually by about 1.34 km2. Furthermore,the stage-storage capacity curves for future periods (prediction curves) were assessed and comparedwith adopted prediction curves using 2011 bathymetric survey data.

  • 240.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sedimentation and new operational curves for Mosul Dam, Iraq2013Inngår i: Hydrological Sciences Journal, ISSN 0262-6667, E-ISSN 2150-3435, Vol. 58, nr 7, s. 1456-1466Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq. Its storage capacity is 11.11×109 m3 at a maximum operation level 330 m of a.s.l. The dam became operational in 1986 and no survey has been conducted to determine its storage capacity and establish new operational curves since this date. In this research topographic map scale 1: 50000 dated 1983 was converted to triangulated irregular network (TIN) format using the Arc/GIS program to evaluate the operational curves. Then the reservoir was surveyed in 2011 to establish the reduction in its storage capacity and to develop new operational curves. The results indicated that the reduction in the storage capacity of the reservoir was 14.73%. This implies that the rate of sedimentation within the reservoir was 45.72×106 m3.yr-1. The results indicated that most of the sediment was deposited within the upper zone of the reservoir where the River Tigris enters the reservoir.

  • 241.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    Sediment delivered in the upper part of Mosul reservoir using physical model2012Inngår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 6, nr 11, s. 1544-1550Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mosul dam is the biggest hydraulic structure in Iraq located on the River Tigris 60 km northwest of Mosul city. Its storage capacity is 11.11 × 109 m3 and it had been in operation since 1986. A physical distorted model with movable bed having a vertical scale 1:100 and a horizontal scale 1:1000 was used to conduct the experiments relating the water level at the reservoir and water discharge upstream the reservoir with the bed load transport rate. The model represents the first 15 km of most northern part of Mosul dam reservoir. The construction of the model was based on bathymetric survey conducted in 2009. Twenty-four experiments were executed using four different discharges (0.5, 1.0, 1.5, and 2.0 L/s) which represent the average discharges in the flood period of River Tigris. At each individual discharge six operations were assumed where the reservoir’s water level was 305, 307, 309, 310, 312, 315 meters above sea level respectively. In all the experiments conducted, bedload transport was measured in the physical model at section representing the River Tigris 1 km upstream the reservoir. The results showed that the bedload rate was decreasing when the water level within the reservoir was increasing. It was also evident that bedload transport rate dramatically decreased at level 310 meter above sea level onward. This is due to the fact that at this level represent the effect of backwater which was noticeable on the river cross section.

  • 242.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    The effect of operation of Mosul dam on sediment transport in its reservoir2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Mosul dam is the biggest hydraulic structure in Iraq located on the River Tigris 50 Km north of Mosul city. Its storage capacity is 11.1 x 109 m3 and it had been in operation since 1986.A physical model representing the most northern part of Mosul dam reservoir was used to conduct the experiments. The construction of the model was based on field survey conducted in 2010. Twenty-four experiments were executed using four different discharges (500, 1000, 1500 and 2000 m3/s respectively). At each individual discharge six operations were assumed where the reservoirs water level was 305,307,309,310, 312, 315 MSL respectively. In all the experiments conducted, bedload transport rate was decreasing when the water level within the reservoir was increasing. It was also evident the bedload transport rate dramatically decreased at level 310 onward. This is due to the fact that at this level the effect of backwater was noticeable on the river cross section

  • 243.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research—KRG, Erbil.
    Monitoring and Evaluating the Sedimentation Process in Mosul Dam Reservoir Using Trap Efficiency Approaches2015Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, nr 4, s. 190-202Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Reservoirs are usually exposed to sediment accumulation problems that will lead to reduction in their storage capacity. This problem directly affects the performance of the dams and causes shortage of their useful life. The simplest technique to estimate sediment deposition rate is using sediment rating curve with sediment trapping efficiency (TE) of the reservoir. Many empirical and semi-empirical approaches have been suggested for to determine this term depending on the annual inflow rate, reservoir characteristics and features of the catchments area. In this study six different empirical methods depending on the residence time principle (water retention time) were used. These approaches were reviewed and applied to determine TE of Mosul dam reservoir (MDR) for period 1986 to 2011. The monthly operating data for inflow, outflow and water elevations for MDR were used to determine monthly TE and long-term TE for whole period of MDR using the mentioned methods. Furthermore, the monthly inflow rate for River Tigris upstream MDR, its sediment rating curve and sediment feeding from valleys around MDR were used to estimate the amount sediment coming to the reservoir. The results provided by these methods for TE withsediment coming to MDR were used to compute the amount of sediment deposited in MDR on monthly bases during this period. The results obtained were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam. The results showed all the mentioned methods gave convergent results and they were very close to bathymetric survey results for estimating the volume of sediment deposited especially that proposed by Ward which gave 0.368% percentage error. Furthermore, the result computed using monthly TE gave good agreement if compared with that long-term TE where the percentage error was ranging between −3.229% to 1.674% for monthly adopted data and −4.862% to −2.477% for whole period data. It is believed that this work will help others to use this procedure on other reservoirs.

  • 244.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research, Kurdistan Region.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Expected Future of Water resources within Tigris–Euphrates Rivers basin, Iraq2014Inngår i: Journal of Water Resource and Protection, ISSN 1945-3094, E-ISSN 1945-3108, Vol. 6, nr 5, s. 421-432Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Iraq is one of the riparian countries within basins of Tigris-Euphrates Rivers in the Middle East region. The region is currently facing water shortage problems due to the increase of the demand and climate changes. In the present study, average monthly water flow measurements for 15 stream flow gaging stations within basins of these rivers in Iraq with population growth rate data in some of its part were used to evaluate the reality of the current situation and future challenges of water availability and demand in Iraq. The results showed that Iraq receives annually 70.92 km3 of water 45.4 and 25.52 km3 from River Tigris and Euphrates respectively. An amount of 18.04 km3 of the Tigris water comes from Turkey while 27.36 km3 is supplied by its tributaries inside Iraq. The whole amount of water in the Euphrates Rivers comes outside the Iraqi borders. Annual decrease of the water inflow is 0.1335 km3 year-1 for Tigris and 0.245 km3 year-1 for Euphrates. This implies the annual percentage reduction of inflow rates for the two rivers is 0.294% and 0.960% respectively. Iraq consumes annually 88.89% (63.05 km3) of incoming water from the two rivers, where about 60.43 and 39.57 % are from Rivers Tigris and Euphrates respectively. Water demand increases annually by 1.002 km3; of which 0.5271 km3 and 0.475 km3 within Tigris and Euphrates basins respectively. The average water demand in 2020 will increase to 42.844 km3 year-1 for Tigris basin and for Euphrates 29.225 km3 year-1 (total 72.069 km3 year-1), while water availability will decrease to 63.46 km3 year-1. This means that the overall water shortage will be restricted to 8.61 km3.

  • 245.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research, Kurdistan Region.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sedimentation processes and useful life of Mosul dam Reservoir, Iraq2013Inngår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 10, s. 779-784Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The sedimentation process is the most important problems that affect directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic assessment of the storage capacity and determining sediment deposition patterns is an important issue for operation and management of the reservoirs. In this study, bathymetric survey results and an analytical approach had been used to assess the characteristics of sedimentation and estimate the useful life of Mosul Reservoir. It is located on the Tigris River in the north of Iraq. The water surface area of its reservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330 m a.s.l). The dam started operating in 1986. No detailed study was yet carried out to assess its reservoir. The present study indicated that the annual reduction rate in the dead and live storage capacities of the reservoir is 0.786% and 0.276% respectively. The observed results (bathymetric survey) and algebraic formula show approximately that the useful life of Mosul dam reservoir is about 125 years. Furthermore, the stage-storage capacity curves for the future periods (prediction curves) were established using bathymetric survey data.

  • 246.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust emission from unpaved roads in Luleå, Sweden2013Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 1, s. 1-13Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The dust emission from unpaved roads, if not controlled, can cause enormous problems. Though a few real-world measurements of road dust have been done by automated samplers in Sweden, measurement by BSNE (Big Spring Number Eight) and the estimation of total dust generation from vehicle driving is rare. This study measured and analyzed dust emission by BSNE at two unpaved roads in Luleå, Sweden, at the driving speed of 20, 30, 40, and 50 km/h different heights. Even though US EPA excluded vehicle speed as a parameter in estimating dust emission factors for unpaved roads, this study confirmed a strong dependence of dust emission on vehicle speed. This is in agreement with several recent studies which concluded dust emission increases with driving speed exponentially or linearly, however the power law is the best description for the data from this study. The comparison with estimated dust emission by US EPA’s equation showed the equation underestimates the dust emission more than 50 percent when vehicle speed and silt content is higher than 25.40km/h and 2.17 percent respectively. There might be some interrelationship between driving speed and silt content in road surface.Earlier researchers have reported increased dust emission with increasing silt content and this is confirmed by this study.

  • 247.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust generation within the vicinity of Malmberget mine, Sweden2011Inngår i: Applied Mechanics and Materials, ISSN 1660-9336, E-ISSN 1662-7482, Vol. 90-93, s. 752-759Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mining activities are usually associated with environmental impacts, particularly that of air pollution by fugitive dust. Malmberget mine is one of the most important iron mines in Sweden and the dust problem has been noticed by the inhabitants for a long time. Dust collectors had been installed to measure the dust fallout around the mining site. In this research the dust fallout recorded during the period August 2006 till July 2010 were analyzed. Generally speaking the amount of dust fallout was decreasing year by year due to some implemented dust control methods. Mining activities produced more dust during summer than winter. The peak value was 265g/100m2/30d appeared in May 2007, and the lowest dust fallout was 25g/100m2/30d happened in August 2009. Dust was determined to be originated from the open pit area and the industrial center area. Truck transportation on the haul roads, wind erosion of stockpiles and exposed areas were the main activities that caused dust generation.

  • 248.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Estimation of road dust using BSNEs2013Inngår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 5, s. 567-572Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mining is a core industry in Sweden and plays an important role in the economic development of the country. Though the importance of mining dust has been well recognized, the quantification of dust production with regard to individual source activity has rarely been done in Sweden. Depending on the type of source activity, dust estimation method can be chosen from three alternatives: exposure profiling methods, back calculation method, and wind erosion prediction method. Also included in the paper is an example of experiment, which was executed on two unpaved roads in Lulea, Sweden by using exposure profiling method. The experiment concluded that dust emission due to vehicle transportation is strongly dependent on traveling speed and road bed material.

  • 249.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of dust fallout at malmberget mine, Sweden for the period August 2009 to August 20102011Inngår i: Journal of Advanced Science and Engineering Research, Vol. 1, nr 2, s. 246-260Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dust is produced when mining operations take place. The transportation and deposition of dust depend mainly on climatic factors, as well as land surface characteristics. Malmberget mine operated by Luossavaara-Kiirunavaara Aktiebolag is one of the most important iron mines in Sweden. The mining area includes an area with a huge open pit and an industrial center. Both sites are surrounded by residential areas where people are suffering from dust problems. The collected dust from 26 measuring stations during the period 2001 to 2010 has been analyzed using the surfer 9.0 program. Generally speaking the dust fallout in summer was higher than that in winter and the volumes decreased through time as a result of implemented dust control methods. Analysis of the data from August 2009 to August 2010 indentified two sources of dust generation. One was located close to the open pit, and the other near the current mining industrial center. Among all the measuring stations, the maximum and minimum values within the year were 1284 g/100m2/30d and 9 g/100m2/30d, respectively. Dust production around the Malmberget mine was attributed to three reasons, namely, wind erosion of the exposed area close to the open pit, truck transportation on haul roads, and wind erosion of stockpiles. In addition to climatic factors, the variation of dust detected depended on mining activities and road construction.

  • 250.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Measurement of dust emission from a road construction using exposure-profiling method2013Inngår i: Journal of Natural Science, ISSN 0075-4307, Vol. 5, nr 12, s. 1255-1263Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Road construction is one example of heavy constructions that may have a substantial temporary impact on local air quality. Construction of Luleå Road during the summer 2013 generated a great deal of dust emission. US EPA recommended exposure-profiling method was used to measure dust emission. Inexpensive BSNE dust samplers were used instead of high volume samplers. The objective was to give a general idea of the amount of dust generated due to the construction work. Dust generation related to weather was discussed conditions. Estimated threshold wind velocity for road surface materials at the height of 2m were 12.88m/s, 12.88m/s and 24.76m/s which were lower measured wind velocity, indicated no dust generated from wind erosion. Dust masses for 7 sampling periods show dust generation had a close relation with moisture content of surface material. Wind speed, humidity had minor or no effect. The estimated dust emission rate in the construction work during the measuring period was 22.86kg TSP/d, 6kg/d was from construction work and 16.86kg/d was generated due to traffic on temporary roads.

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