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In this study, a mixing procedure of sulfur-rich soil and cement-based binder to enhance the soil’s unconfined compressive strength (UCS) was tested in field conditions for geotechnical applications. The focus was to evaluate uniformity of industrial size soil-binder mixture, blended by existing method. This paper outlined sampling strategy and the number of samples needed for a valid uniformity evaluation. Moreover, this study emphasized the difference between field mixing and laboratory mixture preparation by comparing UCS of stabilized soil samples in the field and UCS of corresponding samples mixed and prepared in the laboratory environment. In the field, soil and cement were blended in two to four stages with 5% and 7% cement—the percentages being based on the soil’s dry weight under field conditions. Samples were taken from the field mixtures after each stage. Since the number of samples needed to be representative of mixture characteristics for large-scale mixing is not standardized, this field experiment included two phases. The first phase was dedicated to finding a sampling strategy for a large soil pile along with measuring UCS of collected samples. In the second phase, sample collection was conducted based on the results of sampling strategy from the first phase. In the laboratory, samples with percentages of binder similar to the amount of binder in the field were also prepared. Both field and laboratory samples were prepared using the tapping method in the laboratory for UCS test. Samples were cured under similar conditions for 28 days. The results showed that the uniformity of mixture improved after each additional mixing stage. In addition, while spots with low UCS were observed in the second mixing step, these spots were eliminated in the third mixing step, and results of the UCS tests were comparatively uniform. Moreover, comparison of the samples revealed that the UCS of the laboratory mixture is higher than that of the field mixture. This showed that even though the UCS is a good standard for comparing the strength of different soils stabilized with different percentages or types of binders in the field mixing, the actual strength of the stabilized mixtures under field circumstances is lower than that in laboratory prepared mixtures. Validerad;2023;Nivå 2;2023-04-14 (hanlid);Funder: Interreg Botnia-Atlantica program Sustainable treatment of coastal deposited sulfde soils (STASIS)

Understanding the mechanism of excess pore water pressure generation in subgrades is essential for not only designing but also further maintenance purposes. The primary goal of this research was to investigate excess pore water pressure generation in fine granular materials under cyclic loading. A series of undrained cyclic triaxial tests were performed to study the excess pore water pressure generation in two selected fine granular materials: (1) railway sand and (2) tailings. The excess pore water pressure response of these materials was evaluated in terms of density conditions, number of cycles, and applied cyclic stress ratios (CSR). As a result, excess pore water pressure accumulated over time due to cyclic loading. However, its accumulation was significantly dependent on the governing factors, i.e., densities, CSR values, and material types. The excess pore water pressure exhibited a slight increase at low CSR values, but a sharp increase was observed at higher CSR values, which ultimately led to a failure state after a certain number of cycles. In addition, under the same loading conditions, the samples that had higher relative compaction showed better resistance to cyclic loads as compared to those with lower relative compaction. Finally, a relationship between excess pore water pressure and cyclic axial strain of the fine granular materials was discovered. Validerad;2023;Nivå 2;2023-03-27 (hanlid);Funder: Swedish joint research program for road and railway geotechnology Bransch-samverkan i grunden (BIG); Swedish Hydropower Centre (SVC)

To enable assess slope stability problems efficiently, various machine learning algorithms have been proposed recently. However, these developments are restricted to two-dimensional slope stability analyses (plane strain assumption), although the two-dimensional results can be very conservative. In this study, artificial neural networks are adopted and trained to predict three-dimensional slope stability and a program, SlopeLab has been developed with a graphical user interface. To reduce the number of variables, groups of dimensionless parameters to express stability of slopes in classic stability charts are adopted to construct the neural network architecture. The model has been trained with a dataset from slope stability charts for fully cohesive and cohesive-frictional soils. Furthermore, the impact of concave plan curvature on slope stability that is usually found by excavation in practice is investigated by introducing a dimensionless parameter, relative curvature radius. Slope stability analyses have been conducted with numerical calculations and the artificial neural networks are trained with dimensionless data. The performance of the trained artificial neural networks has been evaluated with the correlation coefficient (R) and root mean square error (RMSE). High accuracy has been found in all the trained models in which R > 0.999 and RMSE < 0.15. Most importantly, the proposed program can help engineers to estimate 3D effects of a slope quickly from the ratio of the factors of safety, FS3D/FS2D. When FS3D/FS2D is large (such as larger than 1.2), a 3D numerical modelling on slope stability analyses that can consider complex 3D geometry and boundary condition is advised. Validerad;2021;Nivå 2;2021-08-17 (johcin)

When a dam is built, its safety becomes a constant concern for the owner, the public and for governments. Therefore, continuous observation through routine inspections and safety reviews become necessary. Acting as protectors of public safety, governments and professional organizations save no effort in the promulgation of legislations and laying out guidelines for such inspections and reviews. These issues are discussed here starting with the basic first step of visual inspections by the operators and the follow up of detailed safety reviews by specialists. Careful visual inspections assisted by instrumentation measurements may reveal an early negative issue such as, but not limited to, increased seepage, increased uplift pressure, signs of weakness like cracking in the body of the dam, or dams’ slope sloughing, and even damaged hydraulic control equipment. Documenting and reporting these observation helps in taking remedial measures in good time and may lead to more intensive safety reviews. Suggested check lists for the inspection engineers are given here, but these may be tailored for each dam according to its needs. These lists cover issues common to both embankment and concrete dams, and include other specific issues related to each type of them. Metal equipment take their share by listing such areas as corrosion, fatigue and cracking, tear, and wear and so on. Instrumentation measurements are also given their due consideration by giving brief mention of types of measurements needed and points to be observed in instrumentation control work. Finally, guidelines, rules, and legislations for Dam Safety Reviews are generally discussed giving examples from four countries in the world. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Remote sensing is the collection and interpretation of information of an object, areaor phenomenon by a recording device that is not in physical or intimate contact with the object or phenomenon under study. It generally refers to the use of satellite borne or airborne sensors to capture the spectral and spatial relations of objects and materials on Earth from the space. This is done by sensing and recording reflected or emitted electromagnetic radiation from the objects. A brief history of satellite remote sensing is given in this review but the bulk of it is devoted to the scientific satellites launched into orbit and their sensors tracking, and presenting changes in water resources fields. The used technologies and satellite systems for monitoring movements and changes include American GNSS, GPS, the Russian GLONASS, Europe’s European Satellite Navigation System (GALILEO), China’s COMPASS/BeiDou, the Indian (IRNSS); Japan’s (QZSS) and many others. Details are presented on the present (LANDSAT), the Moderate Resolution Imaging Spectroradiometer (MODIS), as well as Synthetic Aperture Radar (SAR), and RADARSAT, JERS‐1, and ERS, which are developed by various countries, especially the USA. These sensors have the refined capability of providing estimates of variables, which depending on the purpose and design of the sensor, can follow critical issues related to water management problems. This review presents examples of actual studies carried out including; building databases of small dams and lakes on regional scale, derivation of volume vs. elevation and surface area vs. elevation of hundreds of reservoirs around the world, various bathymetric reservoir surveys, siltation of reservoirs and catchment areas erosion problems, monitoring of water quality changes, and above all monitoring dam deformation and stability problems of dams. The presented case studies cover the use of these different sensor together with the imagery used, their sources, methods of interpretation, validation and gives presentation of the end results. This review, which is only a very brief presentation of satellite remote sensing applications concludes that; in spite of the large volume of research done on this subject so far, which this review cites some of them , the expected future developments in satellite remote sensing technology coupled with advances in algorithms and models used in refining satellite imagery and validating the results will bring more accurate results and less laborious treatment work in addition to wider scope of applications. Validerad;2020;Nivå 1;2020-10-08 (johcin)

The use of geophysical methods in dam sites investigations and safety monitory has proved their good value and versatility in many earthfill dam sites as early as the 1920s. In the following years great development has occurred in the methods, application procedures and tools used. They may be considered today as good ways for carrying out observation tasks on existing dams in non-intrusive and much faster and cheaper ways than the traditional geotechnical methods. It is possible using them to discover anomalies in the dam body or its foundation at an early stage and allowing quick intervention repair works. These methods seek to register and present variations in the basic geotechnical material properties in dams such as; bulk density, moisture content, elasticity, mechanical properties of rocks, electrical resistivity and mineralogy and magnetic properties and so forth. Such variations can indicate increasing seepage flow, progression in cracks’ sizes, formation of voids, caverns and other instability manifestations. Depending on how any investigation is carried out and the targeted anomaly, there is now selection of these methods such as: Electromagnetic Profiling (EM), Electrical Resistivity Tomography (ERT), Self- Potential (SP), Ground Penetration Radar (GPR), variety of Seismic Methods (SM) which can be applied using such equipment as in Seismic refraction, Seismic Reflection, Multi Analysis of Rayleigh surface waves (MASW) instruments, or using Refraction Micrometer (ReMi), macro-gravity method, and Cross-Hole Seismic Tomography. In addition, Temperature Measurements and other less used methods can be used like Microgravity measurement, Magnetic Profiling and Radio Magnetotelluric methods. An attempt is made here to cover the details of these methods, their advantages and limitations and to prove their usefulness in many dam sites all over the world. One observed issue is their adaptability to embankment dams more than to concrete dams and their popularity for checking seepage related problems and material changes within dam bodies and their foundations such as formation of voids and sinkholes. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Dam Safety and dam incidents are treated here looked at from the "Human Factors" perspective. An attempt is made to explore these factors as an important drive in impairing dams’ safety and increases their risks. Distinction is drawn between the "Normal Human Caused Incidents" and the "Extraordinary Human Caused Incidents" together with the description of their root origins and subsequent consequences. The first type includes unintentional mistakes, errors and flaws committed by the operators of dams inadvertently, in addition to negligence, lack of experience or overconfidence. Such failings can happen in manual operation of dams, or through the use of their Supervision, Control and Data Acquisition (SCADA) systems as in industrial control system (ICS). They can occur also due to flaws in software or even in the application of information and communication technology (ICT) in remote control operations. As for the second group; the extraordinary human factors, they are defined here as those committed by man with the full understanding of their possible damage. They are done purposely for destabilizing dams after thoughtful and carefully meditated decision making process and they are manifested in acts of war, sabotage and terrorists actions. In this modern age, these acts are characteristics of hackers’ attacks on dam(s) operating systems. This is done through the use of cyberspace by the widespread interconnected digital technology with the accompanying advances in the communication technologies. As such, these technologies have made remote control of such systems possible. Not limited to this, dams remain now, as they were always in the past, the obvious targets in wars and conflicts to inflict losses on the enemy and to use them as weapons, and for terrorism actions for challenging governments. Examples of the aforementioned threats are described with examples given from real cases to elucidate the dangers involved. Lessons to be learned from these incidents are derived and recommendations are presented to be followed to avoid risky situations. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Lack of land for waste disposal is one of the main problems facing urban areas in developing countries. The Sulaimaniyah Governorate, located in northern Iraq, is one of the main cities of the country in the Kurdistan Region, covering an area of 2400 km2. Currently, there is no landfill site in the study region that meets scientific and environmental requirements, inappropriate dumping of solid waste causes adverse effects on the environment, economic and urban aesthetic. To overcome with this phenomenon, it is very crucial to suggest a landfill site, even in countries that recycle or burn their waste to protect the environment. Landfill sites should be carefully selected by considering all regulations and other restrictions. The integration of geographic information systems and multi-criteria decision analysis is used in this study to select suitable landfill locations in the region, for this purpose, thirteen layers are prepared according to their importance including urban area, villages, rivers, groundwater depth, slope, elevation, soil types, geological formations, roads, oil and gas field, land use classification, archaeological site and power lines. Two different methods (simple additive weighting and analytic hierarchy process) are implemented in a geographical information system to obtain the suitability index map for candidate landfill sites, where all these sites satisfied the scientific and environmental criteria which were adopted in this study. The comparison of the maps resulting from these two different methods demonstrates that both methods produced consistent results. Validerad;2020;Nivå 1;2020-04-28 (johcin)

Three-dimensional finite element (FE) simulations were performed to further develop the Swedish design guidelines for geogrid-reinforced timber pile-supported embankments, also known as lightly piled embankments. Lightly piled embankments are constructed mainly in areas which typically have highly compressible soils, and the method utilises untreated timber piles as its key feature. The timber piles are installed in a triangular arrangement instead of the more common square arrangement, with a centre-to-centre distance of 0.8–1.2 m. The aim of this study was to evaluate the current standard using FE modelling setups with square and triangular pile arrangements with varying centre-to-centre distances, based on a typical road foundation case. The evaluation mainly focused on comparing the embankment settlements, as well as the load and stress distribution in the embankment, the piles and the geosynthetic reinforcement. As part of the evaluation, a state-of-the-art study was done on international design guidelines and analytical models. From the FE simulations, no evident difference in mechanical behaviour was found between the triangular and square piling patterns. The maximum allowed centre-to-centre distance between piles can potentially be increased to 1.4 m, decreasing the number of piles by as much as one third. Validerad;2022;Nivå 2;2022-01-01 (johcin)

Water flow direction and velocity affect and controls erosion, transport and deposi- tion of sediment in rivers, reservoirs and different hydraulic structures. One of the main structures affected is pumping stations within the dams wherein the velocity distribution near the station intake is disturbed. The two-dimensional (2-D) HEC-RAS 5.01 model was utilized to study, analyse and evaluate the effects of pumping rates and flow depth on the flow velocity distribution, flow stream power and their effects in the Mosul Dam reservoir. The pumping station was considered as a case study. The station is suffering from sediment accumulation around, and in, its intake and suction pipes. The main inflow sources to the reservoir are the Tigris River and run-off from the valleys within its basin. The reservoir was divided into two parts for the present study, including the upper part near the pumping station (analysed as a two-dimen- sional zone), while the lower part was analysed as a one-dimensional flow to reduce the simulation period computation time (1986–2011). Different operation plans (i.e. pumping rate and water depth) were considered. The results of the depth-averaged velocity model indicated that when the pumping station was working at a range from the designed full capacity (100% to 25% of its full capacity), the maximum flow ve- locity increased from 75 to 4 times the normal velocity when there is no pumping dependent on pumping rate and flow depth. For the same operation plans, the flow stream power varied from around zero values to 400 times at full pumping capacity and low flow depth. For sediment routing along the reservoir, the considered statisti- cal criteria indicated the model performance in estimating the total sediment load deposition and invert bed level is much better than in the case of erosion and deposition areas for different considered bed sections of the reservoir. Validerad;2020;Nivå 1;2020-03-30 (alebob)

Field sampling for evaluation of mechanical behaviour in embankment dams is not easily performed, because the performance and the safety of the structure may be unfavourably affected. A non-destruc...

Fine-grained soils are often not suitable as subsoil for roads or railways or other large-scale constructions due to their sensitivity to settlements as well as their frost susceptibility. The engi ...

Zusammenfassung Aufgrund ihrer Frostempfindlichkeit eignen sich feinkörnige Böden oftmals nicht als Unterbau für Straßen oder Bahntrassen. Die Eigenschaften dieser Böden können durch Stabilisierung mit hydraulischen Bindemitteln deutlich verbessert werden, was in Ländern mit warmgemäßigtem Klima wie Deutschland üblich ist. In dem vorliegenden Beitrag wird eine Laborstudie an einem schwedischen Ton präsentiert, der mit einem Recyclingbindemittel stabilisiert wurde. Die Durchführung und Interpretation der Studie berücksichtigt landestypische Randbedingungen von Schweden. Die Studie umfasst zwei verschiedene Bindemittelgehalte (4 % und 7 %) sowie unbehandelten Ton, drei verschiedene Erhärtungszeiten (14, 28 und 90 Tage) vor zwölf Frost-Tau-Wechseln sowie eine anschließende Erhärtungszeit. Die Bedingungen während des Erhärtens entsprachen kalten Klimaverhältnissen, das heißt + 4 °C. Als Maß für die Festigkeitsentwicklung wurde die einaxiale Druckfestigkeit verwendet. Die Ergebnisse zeigen, dass die Festigkeit des Bodens durch Stabilisierung deutlich zunimmt und dass eine Zunahme auch nach Frost-Tau-Wechseln sichtbar bleibt. Die Nacherhärtungszeit könnte eine weitere Erhärtung ermöglichen, was die etwas höheren Festigkeitswerte vermuten lassen.

The rocking response of embedded foundations in sand is studied, combining centrifuge modelling and numerical analysis. In total, 51 centrifuge model tests are conducted at ETH Zurich, varying the embedment ratio D/B and the factor of safety against vertical loading (bearing capacity), Fs. The experimental results are used to validate three-dimensional finite-element models, which are subsequently employed for a parametric study. The initial two phases of non-linear response are studied, namely quasi-elastic and non-linear response, while the third phase (plastic response) will be examined in a forthcoming publication. Regarding small-strain rocking stiffness, Kr (first phase), an extended formula is proposed, accounting for soil inhomogeneity along the embedded sidewalls. Kr is shown to decrease with Fs, due to initial soil yielding from vertical loading. The formula is further extended to account for the role of Fs, offering improved estimation of small-strain rocking stiffness. With respect to the non-linear response (second phase), it is shown that the degradation curves of rocking stiffness with rotation can become approximately dimensionless, if the rotation θ is normalised to a characteristic rotation, θs. The increase of D/B leads to a reduction of the normalised rotation θ/θs at which the non-linear response is initiated, due to the increasing participation of sidewall friction.

Iraq currently undergoing the problem of water shortage, although Iraq has two Rivers (Euphrates and Tigris) pass throughout most of its areas, and they have represented a major source of water supply. In the current research, to evaluate the quality of the Euphrates river in Iraq based on the values of total dissolved salts (TDS), the TDS concentrations were collected from sixteen sections along the river in the three succeeding years (2011, 2012, and 2013). The evaluation of the river was done depending on the classification of (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland). of rivers for drinking uses. Inverse Distance Weighting Technique (IDWT) as a tool in the GIS was employed to establish the maps of the river that using interpolation/prediction for the TDS concentrations to each selected year and the average values of TDS for these 3 years. Based on the five categories of rivers’ classification of the TDS concentrations according to the (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland), the Euphrates river was classified, and the maps of classification for the years 2011, 2012 and 2013 and the average values for 3 years were created. The average values for 3 years of TDS along the Euphrates river indicated that the sections from SC-1 to SC-4 as moderate-water-quality-Category-3, the sections from SC-5 to SC-10 as poor-water-quality-Category-4, while the sections between SC-11 to SC-16 as very poor-water-quality-Category-5. The interpolation maps showed that the Euphrates river in Iraq was ranged from moderate water quality (Category-3) to very poor water quality (Category-5). Validerad;2021;Nivå 2;2021-09-10 (alebob);Finansiär: Al-Mustaqbal University College, Iraq

Iraq relies in its water resources on the Rivers Tigris and Euphrates and their tributaries. It used to be considered rich in its water resources until 1970. Then, the water quantity started to decrease due to the construction of hydrological projects within the riparian countries as well as the effect of climate change. In addition, water management planning in Iraq requires number of strategies that can help to overcome the water shortage problem. In this work, the negative problems are discussed and solutions are given to solve the water shortage problem. Keywords: Water Scarcity, Tigris, Euphrates, Climate Change, Iraq.

The awareness to tailings dam safety monitoring and reviews has increased by the catastrophes resulting from failures of such dams worsened by increasing tailings waste and construction of larger dams. The losses born by the mining industry from high costs of compensations and environmental rehabilitation work have brought this matter into focus. In the present article the need for safety monitoring programs of tailings dam is highlighted and mode of failures and factors leading to them are described. Basic principles of such programs are investigated with all phenomena needing observation described and their impacts explained. As in conventional dams this work is carried out by visual inspections and use of similar methods and instruments. In similar manners in both types of dams’ observation and measurements are done for measuring seepage water quantity and quality, phreatic surface level and pore pressure and total earth pressure values in addition to deformation measurements; and all are done by similar devices and methods such as weirs, piezometers, inclinometers, settlement plates and geodetic surveying. Basic differences between safety monitoring systems of the two types of dam, however, are presented in a tabular form. The continuity of safety monitoring of tailings dams is emphasized not only during the long construction phase but also after that in the abandonment and closure phase which can last indefinitely in order to watch for possible adverse effects on the environment and ecosystem due to the winds eroding and carrying of poisonous tailings contents, in addition to contaminated seepage water entering surface water streams and ground water. Justifications for using real time monitoring systems for recording and transmitting all data to the control center are presented with emphasis given on savings in both labor and time and need for the discovery of warning signs enabling raising earlier the alarm of possible failure or incident and the early taking of preventive measures. In this article it is argued that, in spite of the large investment of installing and running cost of comprehensive dam safety monitoring systems in tailings dams, such costs are justified as they form only a small percentage of the total investment in the tailings facilities projects, and may save huge costs if failure does happen. Such systems may be considered as an additional insurance against such events. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Seismic instrumentation of dams and reservoirs sites is accepted today as a valuable tool to understand significant seismic hazards facing existing dams or future planed dams. With the advent of digital seismic accelerometers and recorders, it can now be used today as an integral part of dam safety monitoring systems. Outputs of these instruments help in understanding the dynamic response of dams during earthquake, assessing the damage caused by such events and determining required upgrading works necessary for existing dams and designing of safer dams in the future. Measuring and recording by strong motion seismographs covers the induced Peak Ground Acceleration (PGA), velocity and displacement recorded on time scale to indicate the intensity and frequency of ground vibration at the site during seismic events. Seismometers for such measurements and recordings have undergone considerable evolution and there exist today a variety of these instruments with high degree of refinement which can even provide for remote sensing. In this work, this development is outlined and examples of seismic instrumentation in strategic dams are described. Damages to actual concrete and embankment dams of various types are described indicating the associated PGAs experienced during the mentioned earthquakes. Damages in the form of cracking, increased seepage, additional settlements and displacements are described to show type and extent of possible consequences of such events on dams. The reached conclusion is that seismic instrumentation systems are desirable and highly recommendable for all types of dams; existing and future ones and their high cost is justified by the service they provide. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Sedimentation of reservoirs has its negative impacts on dams, first by reducing useful storage, altering the benefit/cost ratio originally calculated for the dam, and second by reducing the dams’ capacity for flood routing; increasing flooding hazards on the dam itself and for the downstream. More problems can be created by sediments and floating debris during floods on outlet structures by clogging them and thus creating dangerous situations, or damage trash screens leading to even more problems. If these debris and coarse sediments are allowed in, then they may damage dam structures such as gates, spillways intakes in addition to chutes, stilling basins and power penstocks by the mechanical abrasion impacts of such sediments on them. Frequent inspections, especially after floods must be made to ensure proper functioning of such structure and take actions for reducing the damage. In small reservoirs, dredging; although it adds to maintenance cost, may ease the problem, but in very large reservoirs, this may prove unpractical. Designers, therefore, have a duty to consider sedimentation problem seriously in the initial stages of design by: checking the anticipated accumulation of sediments, allowing enough storage free from siltation, foreseeing their negative impacts on intakes and outlet structures and taking design measures to reduce these impacts. At the same time, dam stability calculations shall have to provision for the anticipated new conditions of silting up at the face of the dam. Operators of dams, on the other hand, shall have to keep open eyes for all the negative issues created by sediments and floating debris, repairing damages caused by them and take measures to reduce their impacts in the future. Validerad;2020;Nivå 1;2020-09-29 (johcin)

Tigris River is a major source to supply water for a big part of Iraq. Lately, Iraq has experienced water shortage problems such as variability in climate and the building of huge dams in the upstream countries (Turkey and Iran). In this work, the total dissolved salts (T.D.S.) were measured at fourteen sites on the Tigris River in two periods of the year 2014. The first period consisted of six rainy-months (April–September) and the second period covered non-rainy-months (October-March). Interpolation technique of inverse-distance-weighting (I.D.W.) in ArcGIS was applied to create the prediction maps of the river for (T.D.S.) concentration in both periods. The findings revealed that the (T.D.S.) levels continued to the last site in Al-Qurnah-city (Basrah) from the first site in Fish-Khabur-city (S-1). In the first period, the (T.D.S.) levels at fourteen selected sites were over the levels in the second period. According to World-Health-Organization (2003), the (T.D.S.) concentration on the Tigris River in both periods in 2014 was graded into five classes, then, the prediction maps of the (T.D.S.) classifications were created.

In order to protect the human health as well as the environment from the solid waste negative impacts, landfill sites should be subjected to adopt the criteria that correspond to landfills international requirements. Fifteen criteria were approved of in an arid area like Babylon Governorate, Iraq for landfill siting. As a result, ten landfill sites were chosen in the governorate. A suitable design was suggested for the selected landfill sites. This design consisted of the base liner system and the final cover system. The results for the suggested landfill design (using the HELP model) showed that there was no leachate percolation from waste mass into groundwater. ISBN för värdpublikation: 978-3-030-51209-5, 978-3-030-51212-5, 978-3-030-51210-1

The stabilization of soft soils with hydraulic binder is a common technique all over the world. By means of stabilization the engineering properties of fine-grained soils can be improved, where settlements or stability problems have to be handled. Lime and cement are usual binders. The use of industrial by-products as binders has been investigated and some are already established on the market in combination with cement, as e.g. fly ash or slag. Nowadays the reduction of CO2 is in focus, leading to a search for more by-products from the industry that are suitable to use as hydraulic binder. One of these is cement kiln dust (CKD) that is started to be used commercially as a binder in combination with cement. Fine-grained soils are often frost susceptible i. e. they show frost heave and/or thaw weakening. These typical problems are handled by improvement with hydraulic binder in countries with moderate climate [33]. In countries with cold climate, near surface soil stabilization with hydraulic binder is less used. One reason for this reduced usage are uncertainties about the influence of low temperature on the expected stabilizing effects of the hydraulic binder. Previous research has shown that the strength of the stabilized material is decreased by frost impact, when compared to without frost. New research results have shown a recovering of the strength after a reduction due to frost [1; 2]. In the present contribution, a multiple linear regression analysis is presented for identifying significant influencing factors for soil stabilization of fine-grained subgrade with hydraulic binders in cold environment. The regression analysis is based on the results from three earlier published laboratory studies [3-5], where the unconfined compressive strength (UCS) was used as a measure of strength. The laboratory studies involved different soil types, different binders (mainly by-products), and varying binder contents. The results from the laboratory studies show that the strength increases during curing in cold environment. After twelve freeze-thaw-cycles the strength is reduced for several samples, compared to without freeze-thaw-cycles, but it is higher than without stabilization. A recovering of strength after a subsequent curing time after the freeze-thaw-cycles is visible in some cases for the stabilized samples. The multiple linear regression analysis presented here shows the influence of the binder content, as well as the freeze-thaw-cycles and the curing time, on the strength.

The Governorate of Sulaymaniyah is located in the north of Iraq with a population of 856 990 in 2016. The process of selecting a landfill site is considered as a complicated task with several factors and regulations to take into account. Currently, there are no landfill sites in the Sulaymaniyah Governorate that Governorate that respect the prerequisites of the scientific and environmental criteria. Therefore, in this study, thirteen suitable criteria were selected. These criteria are: groundwater depth, urban area, rivers, villages, soil types, elevation, roads, slope, land use, archaeological sites, power lines, oil and gas field, and geology. These criteria were used in the GIS (Geographic Information System), due to its high ability to manage and analyze various data. In addition, the AHP (Analytical Hierarchy Process) method was used to derive the weightings of criteria, through a matrix of pairwise comparison. In this work, the study site was classified into four different areas according to the Suitability Index for landfill sites, where they all satisfied the scientific and environmental criteria. ISBN för värdpublikation: 978-3-030-51209-5, 978-3-030-51212-5, 978-3-030-51210-1

Frost heave is major problem for infrastructures build in cold regions. Frost heave occurs due to suction (negative pore water pressure) generated due to the freezing process close to the frost line, i.e., at the frozen fringe. To understand and predict these negative pore water pressures is a key factor to accurately calculate the segregation heave, i.e. heave related to the formation of ice lenses. Segregation heave is the major part of the total heave and also the most challenging to predict. Many attempts have been presented in literature where the generated suction during freezing is related to temperatures, temperature gradients, grain size of the freezing soil etc. Very few laboratory tests have been presented in which the actual suction is measured during the ice lens formation process and compared with theoretical estimations. One reason is that these measurements are challenging. This paper presents results from laboratory measurements of generated suction during freezing. Laboratory tests were conducted on a silty soil sample and suction was measured at the frozen fringe using small pore pressure transducers (PPT’s). The samples were subjected to one-dimensional freezing from top to bottom in an open water system at a constant temperature gradient. Temperatures were measured at various points along the height of the soil sample while suction was measured at middle of the sample. Test results have shown that PPTs do not show pressure change in long-term static pressure test under sub-freezing temperature. For suction measurement at the frozen fringe, pore pressure readings should be measured at various points along the sample height.

Groundwater flows from high to low hydraulic head regions. This flow is controlled by Darcy velocity equation. Darcy velocity represents the flow velocity within the cross-sectional area of the soil. Actually, however, groundwater flows at a higher velocity than that of Darcy’s, called seepage velocity. Seepage velocity considers the real area (pores area) that is available for groundwater flow in calculations. There are many applications which are affected by the seepage/Darcy velocity, e.g., underground thermal energy storage systems and contaminants transfer in soil. In spite of the importance of Darcy/seepage velocity in many applications, there is no specific method to depict these velocities on a large-scale map. This paper proposed a tool that can be used to depict the seepage velocity on a large scale. The considered tool is offered by ArcMap/GIS software. To explain how this tool works, Babylon (Iraq) was considered as a study area. ISBN för värdpublikation: 978-3-030-51209-5, 978-3-030-51212-5, 978-3-030-51210-1

When performing predictions of future behaviour and assessments of the safety for embankment dams, numerical modelling if often needed as support. For embankment dams a usual issue is to obtain values of the material parameters for the material in the dam. Sampling is not easily performed, and it could also negatively affect the performance and safety of the dam. One way to determine values of the material parameters is to create a digital copy of the dam by utilizing so called inverse analysis. The created numerical model is calibrated towards field measurements. To make the reality and the numerical model correspond to each other, the values of material parameters for constitutive models are calibrated. The calibration is done by an automatized process. Further, the calibrated model could be used in predictions of future dam behaviour. The methodology has been shown to work for field data containing errors of a usual magnitude.

Small-strain foundation response has mostly been studied analytically, with limited experimental verification against 1g physical model tests. This paper revisits the problem of small-strain foundation response, conducting a series of centrifuge model tests, aiming to eliminate the limitations of 1g testing. A centrifuge modelling technique is developed, combining static pushover and dynamic impulse testing for similar systems. To allow for derivation of meaningful insights, a novel procedure for in-flight measurement of the distribution of shear modulus with depth is also developed. The latter combines spectral analysis of surface waves (SASW) measurement of the shear modulus G0 at the surface, and estimation of the distribution of the shear modulus G with depth using acceleration measurements in shaking tests. A novel centrifuge tube–actuator is developed and employed to discharge spherical projectiles against single-degree-of-freedom models lying on shallow foundations on sand. This allows generating dynamic impulse excitation, which is used to measure the small-strain dynamic rocking stiffness. The developed actuator is versatile, and was also used for in-flight SASW testing. The centrifuge model tests are shown to confirm the widely used and well-known formulas. This good agreement can also be seen as a confirmation of the validity of the developed experimental techniques.

A freezing test apparatus was supplemented with a digital camera to allow for recording and monitoring one-dimensional freezing tests to analyze the development of ice lenses via particle image velocimetry (PIV) in the laboratory. Two tests on disturbed, partially saturated samples of silt loam were conducted. Image recording and correlation analyses provided detailed information about frost front penetration and ice lens formation(s) under varying temperature boundary conditions. Thawing has also been regarded in further studies. Results of the image analyses were compared to readings from conventional displacement measurements during the same test. Significant agreement between the results of image analyses and displacement measurements has been found. Advantages and disadvantages of utilizing image analysis methods were discussed. Potential remedies for overcoming the drawbacks of using image analysis are suggested. Image analysis is shown to be a viable method in further understanding of frost heave mechanisms.

Mosul Dam is an earth fill dam, with a storage capacity of 11.11 km3 constructed on highly karstified gypsum beds alternating with marl and limestone. After impounding in 1986, seepage locations were recognized. The dam situation now indicates that it is in a state of extreme relative risk. If it fails, then 6 million people will be affected and 7202 km2 area will be flooded. Grouting operations will elongate the life of the dam but will not solve the problem. Building a protection dam downstream will be the best measures to secure the safety of the downstream area and its’ population.

The development in society means that infrastructure like ballasted railway systems is facing challenges due to requests for a increased number of high-speed trains and heavier freight trains. This implies that ballasted railways get an increased impact from larger dynamic loads. The question is how the ballasted railways are today affected by dynamic loading and how will an increase in train speed and weight change the soil behavior within the railway embankment. A method of investigating soil behavior is via geophysical measurements. Accelerometers are commonly used for vibration measurements and by installing them on trains, measurements are possible to perform for complete railway sections. The knowledge of Eigen frequencies for various track components and soil layers are essential when considering frequency analysis of accelerometer measurements. Specifically, this means that the analysis is about detecting resonance of different components. From the actual case study, a good correlation is obtained between the expected Eigen frequencies and the measurement results. Thus, an assessment of the dynamic loadings influences on various soil layers and ballast has been possible to perform. Resonance of a soil layer means that the particles will be rearranged and degraded. For the case when saturated soil layers are subjected to resonance a phenomenon called liquefaction can occur if the pore pressures increases to the level were soil layers lose their effective stresses. Therefore, the most critical finding in this study is liquefaction because it leads to a loss in bearing capacity followed by settlements. Old railway tracks where little or no information exists of the soil conditions are the most suitable areas were this measurement and analysis method is of special use. Consequently, conventional borehole sampling can be reduced. ISBN för värdpublikation: 978-981-15-0449-5, 978-981-15-0450-1

Seepage velocity is a very important criterion in infrastructure construction. The planning of numerous large infrastructure projects requires the mapping of seepage velocity at a large scale. To date, however, no reliable approach exists to determine seepage velocity at such a scale. This paper presents a tool within ArcMap/Geographic Information System (GIS) software that can be used to map the seepage velocity at a large scale. The resultant maps include both direction and magnitude mapping of the seepage velocity. To verify the GIS tool, this study considered two types of aquifer conditions in two regions in Iraq: silty clayey (Babylon province) and sandy (Dibdibba in Karbala province). The results indicate that, for Babylon province, the groundwater flows from the northwest to southeast with a seepage velocity no more than 0.19 m/d; for the Dibdibba region, the groundwater flows from the west to the east with a seepage velocity not exceeding 0.27 m/d. The effectiveness of the presented tool in depicting the seepage velocity was thus demonstrated. The accuracy of the resultant maps depends on the resolution of the four essential maps (groundwater elevation head, effective porosity, saturated thickness, and transmissivity) and locations of wells that are used to collect the data. Validerad;2020;Nivå 2;2020-08-25 (alebob)

A crisis of water scarcity in the world encouraged researchers, especially in the arid areas to know the nature and quality of all its sources regardless of surface water. The groundwater evaluation for irrigation was suggested by using the model of Water Quality Index for Irrigation (WQIIR) in the ArcMap/GIS Software. This model was applied to 48 wells distributed throughout the Hilla district, Babylon, Iraq. The samples of EC, Ca+2, Mg+2, Cl−1, Na+1, HCO3−1, and SAR for groundwater were collected from these wells during wet and dry seasons in 2016. The generated maps in GIS for the WQIIR model in both seasons were divided into categories based on restriction’s groundwater use for irrigation. These categories consisted of Severe Restriction (SR), High Restriction (HR), Moderate Restriction (MR), Low Restriction, and No Restriction. The areas values and their classification of restriction’s groundwater use for irrigation related to the five categories that resulted within the generated maps in GIS using the WQIIR model in the wet season (in km2) were: 42.79 (SR), 407.05 (HR), 377.77 (MR), 32.39 (LR) and 0.23 (NR) respectively and for the dry season were as follows: 42.79 (SR), 407.05 (HR), 377.77 (MR), 32.39 (LR) and 0.23 (NR) respectively. The areas and the classification categories of restriction groundwater for irrigation calculated based on the values resulted from the WQIIR model have shown variation in the dry and wet seasons.

Most of the third world countries having rivers passing through them suffer from the water contaminant problem. This problem is considered so difficult to get the water quality within the standard allowable limits for drinking, as well as for industrial and agricultural purposes. This research aims to assess the water quality of the Tigris River using the water quality index method and GIS software. Twelve parameters (Ca, Mg, Na, K, Cl, SO4, HCO3, TH, TDS, BOD5, NO3, and EC) were taken from 14 stations along the river. The weighted arithmetic method was applied to compute the water quality index (WQI). The interpolation method (IDW) was applied in ArcGIS 10.5 to produce the prediction maps for 12 parameters at 11 stations along the Tigris River during the wet and dry seasons in 2016. The regression prediction was applied on three stations in the Tigris River between observed values and predicted values, from the prediction maps, in both seasons. The results showed that the regression prediction for all parameters was given the acceptable values of the determination coefficient (R2). Furthermore, the state of water quality for the Tigris River was degraded downstream of the Tigris River, especially at the station (8) in Aziziyah in the wet and dry seasons and increase degradation clearly at Qurnah (Basrah province) in the south of Iraq. This paper considers the whole length of the Tigris River for the study. This is important to give comprehensive knowledge about the contamination reality of the river. Such that it becomes easier to understand the problem of contamination, analyze it, and then find the suitable treatments and solutions.

Fine-grained soils are normally not suitable as subbase in road, railway, and other largescale constructions due to their compressibility, low shear strength, and/or frost susceptibility. Common pr ...

Due to an increase in axle loads, the development of excess pore water pressure and settlement in a railway track foundation of fine-grained subgrade soil can be observed. A thorough understanding of the mechanism of development of excess pore water pressure is essential for understanding the development of settlements and the design of potential ground improvement. In this paper, a three dimensional numerical study is presented, which investigates the effects of an increase in axle loads of trains on both excess pore water pressure and settlement. Special attention is given to a soft soil layer beneath the embankment and the influence of ground improvement (deep soil mixing columns). As a result, an increase in axle loads leads to a considerable increase in both excess pore pressures and settlement in the subgrade layer. This increase is more significant in the case of heavy axle load (32.5 tons) than that of the light axle load (16 tons). In addition, cyclic loading can lead to a considerable increase in both vertical displacements and excess pore water pressure. The use of deep soil mixing columns reduces excess pore water pressures and settlements significantly.

Mosul Dam is multipurpose earth fill dam 3.4km long, 113m in height and its storage capacity reaches 11.11 km3 of which 2.95 km3 dead storage. The dam is located on the River Tigris in the northern part of Iraq about 60km north west Mosul city. The dam was built on highly karstified alternating beds of gypsum, marl and limestone. The dam was operating in 1986 and since then, seepage problems started due to the solubility of the gypsum beds, presence of karstification and the effect of the local groundwater aquifer. To stop the seepage insensitive grouting program was put to ensure the stability of the dam. Despite the injection of large quantities of grouting material, it did not stop the seepage. The situation became worse in 2014 when ISIS occupied the dam area and grouting operations were halted. Recent evaluation of the conditions indicates that the dam is in its worst conditions. The failure models of the dam indicate that 6 million people will be affected, and 7202km2 of land will be inundated. It is believed that to stop this catastrophe, grouting operations should be continued intensively to elongate the span life of the dam. As a permanent solution, another dam should be built downstream Mosul Dam so that it can take the wave of Mosul Dam in case of its failure. Validerad; 2017; Nivå 1; 2017-04-03 (andbra)

The selecting of a site for landfill is considered as a difficult process because many criteria should be involved. The main aim of establishing a landfill is to protect the human and environment. Al-Qasim district is considered as the study area in this work. It is one of the main districts in Babylon Governorate, Iraq. There is no systematic site as landfill that fulfil the environmental and scientific criteria in this area. Therefore, the most important fifteen criteria that suited the environmental requirements were selected in the current study. These criteria are: groundwater depth, urban centers, rivers, villages, soil types, elevation, roads agricultural land use, slope, land use, archaeological sites, power lines, gas pipelines, oil pipelines and railways. Two methods of multi criteria decision making AHP (analytical hierarchy process) and SRS (straight rank sum) were applied to obtain the weights of criteria in dissimilar styles. The raster maps of the selected criteria were prepared and analyzed within the GIS software. Then, the change detection method was implemented to compare the two output raster maps resulted from AHP and SRS methods. Two appropriate candidate sites for landfill were selected to accommodate the cumulative solid waste until the year 2030 in Qasim district. The areas of these sites were 2.766 km2 and 2.055 km2 respectively. Validerad;2017;Nivå 1;2017-09-04 (andbra)

The purpose of this experimental investigation is to obtain strain measurements via optical fibre sensors in the drum geotechnical centrifuge of ETH Zurich. It is part of a test series with main goal to study the behaviour of reinforced slopes subjected to self weight loading and subsequently to an impact from a rockfall event. In total 13 scaled reinforced slope models were built with a height of 180 mm and a slope inclination of 2V:1H, optimising the materials used and the different ways of model making. The maximum g-levels were 50 and 100 g and the impact loading was applied at 50 g. The optical fibre sensors were placed on various layers of the reinforcement and at different positions. Strain measurements that were recorded during different tests are logical and expected, demonstrating that optical fibre sensors can successfully be used for measuring linear strain on reinforcement layers that are tested under enhanced gravity in the geotechnical centrifuge. The experimental set up as well as the opportunities and challenges of these measurements are presented and discussed. Finally, correspondent prototype numerical models were created and analysed and the results of this analysis are compared to the corresponding experimental ones.

The Tohoku earthquake in 2011 caused several damages to the pipeline network in the Tokyo Bay area. Predominantly, the main damages were noticed in the artificial islands, where liquefaction destroyed and deformed numerous embedded pipelines. During a seismic event, lifeline systems are subjected to buoyancy forces in the liquefied soil, causing permanent deformations to pipelines and interrupting their serviceability. The current mitigation methods (backfill improvement) are not suitable for regions prone to future earthquakes because pipe excavation and improvement is time-consuming and costly. Therefore, the aim of this study is to present a new effective mitigation method: the so-called horn-type structure. This innovative mitigation method was analysed with different analytical, experimental and numerical methods.

Nonlinear analysis for reinforced concrete members (R.C.) with two types of bars also with unsaturated and saturated soils was used to represent the models. To control the corrosion in the steel bar that used in R.C. member and decrease the cost, the geogrid with steel bar reinforcement are taken in this study to determine the effect of load-deflection and stress-strain relationships. The finite element method is used to model the R.C. member, bars and soil. A three-dimensional finite element model by ABAQUS version 6.9 software program is used to predict the load versus deflection and stress versus strain response with soil. The results for the model in this study are compared with the experimental results from other research, and the results are very good. Therefore, it was concluded that the models developed in this study can accurately capture the behavior and predict the load-carrying capacity of such R.C. members with soil and the maximum stresses with strains. The results show plastic strain values in the R.C. member with saturated soil are larger than their values in unsaturated soil about (54%, 58%, and 55% and 52%) when the geogrid ratios are (without geogrid, 60%, 40% and 20%) respectively, with the same values of stresses. Validerad;2019;Nivå 2;2019-11-06 (johcin)

Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures are critical for society and industry resulting in direct and indirect costs for all the related stakeholders. Pipeline failures are complex processes, which are affected by many factors, both static (e.g., pipe material, size, age, and soil type) and dynamic (e.g., traffic load, pressure zone changes, and environmental impacts). These failures have serious impacts on public due to safety, disruption of traffic, inconvenience to society, environmental impacts and shortage of resources. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within transportation infrastructure. The aim of this study is to identify failure modes and consequences related to the crossing of pipelines in railway corridors. Expert opinion have been collected through two set of questionnaires which have been distributed to the 291 municipalities in the whole Sweden. The failure analysis revealed that pipe deformation has higher impact followed by pipe rupture at cross-section with railway infrastructure. For underground pipeline under railway infrastructure, aging and external load gets higher ranks among different potential failure causes to the pipeline. ISBN för värdpublikation: 978-981-11-2724-3 PipeXrail

Underground thermal energy storage (UTES) systems are well known applications around the world, due to their relation to heating ventilation and air conditioning (HVAC) applications. There are six kinds of UTES systems, they are tank, pit, aquifer, cavern, tubes, and borehole. Apart from the tank, all other kinds are site condition dependent (hydro-geologically and geologically). The aquifer thermal energy storage (ATES) system is a widespread and desirable system, due to its thermal features and feasibility. In spite of all the advantages which it possesses, it has not been adopted in very shallow groundwater (less than 2 m depth) regions, till now, due to the susceptibility of the storage efficiency of these systems to the in-site parameters. This paper aims to find a reliable method that can be used to find the best location to install ATES systems. The concept of the suggested method is based on integrating three methods. They are, the analytical hierarchy process (AHP), the DRASTIC index method, and ArcMap/GIS software. The results from this method include a criterion that summarizes the best location to install an ATES system. This criterion is depicted by ArcMap/GIS software, producing raster maps that specify the best location for the storage system. The suggested method can be used to find the best location to install the thermal storage, especially in susceptible aquifers.

Rapid growth in urbanized areas is a worldwide phenomenon. The rate of urban growth is very fast in developing countries like Iraq. This study illustrated urbanized area development in Sulaimaniyah Governorate from 2001 to 2017 using different Landsat imagery, Landsat Thematic Mapper (TM) and Landsat Operational Land Imager (OLI). The Environment for visualizing images ENVI 5.3 and GIS software was utilized for image pre-processing, calibration and classification. The Maximum likelihood method was used in the accurately extracted solution information from geospatial Landsat satellite imagery of different periods. The Landsat images from the study area were categorized into six different classes. These are: forest, vegetation, rock, soil, built up and water body. Land cover variation and land use change detection in the area were calculated for over a 17 year period. The Change detection Analysis shows an explosive demographic shift in the urban area with a record of +8.99% which is equivalent to 51.80 km2 over a 17 years period and the vegetation area increased with 214 km2. On the other hand, soil area was reduced by 257.87 km2. This work will help urban planners in the future development of the city. ISBN för värdpublikation: 978-3-030-01439-1, 978-3-030-01440-7

Excessive richness of nutrients in water bodies such as rivers, lakes and ponds lead into deterioration of aquatic life as a results of dense growth of algae. Phosphate is one of the main nutrients that should be controlled to prevent this serious issue. Utilizing low cost material as a phosphate sorbent is offering a treatment method characterized as a sustainable solution. In this study the efficiency of biomass bottom ash BBA as phosphate sorbent material from aqueous solution is investigated. Batch experiments were undertaken, in which a particular mass of BBA was brought into contact with the phosphate solution. The experiments studied the influence of pH (different phosphate solutions were prepared with pH range 4 to 8), temperature (adsorption capacity measured at the temperature range of 10 to 30 °C), and contact time. In addition, the adsorption isotherm models were also applied to better understand the mechanism of phosphate sorption by BBA. The results revealed that the bonding between the cations (BBA surface) and anions (phosphate solution) is significantly affected by the pH of the solution. BBA presents an excellent phosphate sorption, especially, at low pH value and temperature around 20 oC. The method of this research can be adopted as a followed strategy for examination the capability of selected material for phosphorus removal from wastewater. Validerad;2019;Nivå 2;2019-11-06 (johcin)

Badush Dam is a partially completed dam and a unique case of flood reten- tion dams. Its intended main function is to perform flood protection once in its lifetime; that is if Mosul Dam would collapse. In such a case, the Badush dam would temporarily store the whole flood wave and route it safely to the downstream. For this end, the bulk of the reservoir is left dry, while the re- maining volume at the lower part which is intended for power eneration does not give an economic justification for building the full height of the dam. The short duration of the intended use as a protection dam has led to relaxing many design assumptions which have raised concerns over the dam integrity. The current controversy rages now over whether to continue the construction of the dam as it was first designed or to change all that in view of the similar site geology of Mosul Dam. Mosul dam foundations suffer at the moment from the severe continuous dissolution of the soluble materials in its foundation leading to continued maintenance grouting of that foundation. This paper gives an overview of the history of Badush dam, its current design and what new equirements which are needed if it is to replace Mosul Damitself. Validerad;2020;Nivå 1;2019-12-19 (johcin)

Filtration materials coating with metallic oxides represented a good method for phosphate sorption. However, most of the researchers utilize chemicals as a source of metallic oxides and heating process to set the chemicals over the filtration materials. This study is aimed to introduce the furnace bottom ash FBA as a source of metallic oxides; it is available free because it is dumped as a waste material from power generation plants. The method of creating new filter media involves coating the limestone and sand by FBA, and the ordinary Portland cement OPC utilized as binder to binding the mixture materials. The water is the factor which is responsible for activating the OPC. All factors such as mixed materials ratio, water content and age of reaction have subjected to optimization process. The results revealed that the optimal mixture for phosphate removal consists of 40% FBA, 5% OPC from dry weight of supporting material, 35% water ratio from the total weight of FBA and OPC, and 14 days are enough to complete the materials reaction. Limestone-furnace bottom ash LFBA indicated high capacity for phosphate sorption and possibility of efficiency regenerate. This study demonstrates a new method for coating the filtration materials more convenient with sustainability approach. Validerad;2020;Nivå 1;2019-12-19 (johcin)

Dams with core of broadly graded glacial moraines (tills) exhibit signs of internal erosion by suffusion to a larger extent than dams constructed with other types of materials, as reported by Sherard (1979). Garner and Fannin (2010) indicated that internal erosion initiates when an unfavorable combination of soil material, stress conditions and hydraulic load occur. A laboratory program, carried out at Lulea University of Technology (LTU), aims to study the effects of void ratio and hydraulic gradient on the initiation of suffusion of glacial till. It consists of suffusion tests conducted in permeameters with an inner diameter 101.6 mm and a height of 115 mm. Results show, as expected, that the hydraulic conductivity is lower with lower void ratio. Nevertheless, as the hydraulic gradient increases, the hydraulic conductivity reaches steady values. Changes in the hydraulic conductivity suggest variation in the initial void ratio due to detachment of the finer particles from the soil matrix. These fine particles start clogging the lower layers, therefore the rate of water flow decreases and so does the hydraulic conductivity. The hydraulic gradient for which the hydraulic conductivity reaches steady values is considered as the upper limit without suffusion evolved.

Tailings is a waste stream produced by mining industry. It is often stored on the surface in a retaining structure, called tailing impoundment surrounded by tailing dams. Strength property of taili ...

The sound design of landfills is essential in order to protect human health and the environment (air, water, and soil). The study area, Babylon Governorate, is situated in the middle of Iraq, and is distinguished by a hot climate and shallow groundwater. The governorate did not have landfill sites that meet international criteria; in addition, the groundwater depth in Babylon Governorate is commonly shallow. Previously, the most important criteria for the study area and GIS software were used to select the best sites for locating landfills in the major cities of the governorate. In this study, the Hydrologic Evaluation of Landfill Performance (HELP 3.95D) model was applied in order to ensure that there was no leakage of the leachate that results from the waste in the selected landfill sites. It is the most commonly utilized model for landfill design, and it is used to estimate water inflow through the soil layers. For the present study, to avoid groundwater pollution by leachate from a landfill site due to the shallow groundwater depth, compacted waste was placed on the surface using two height scenarios (2 m and 4 m). This design was developed using the soil properties of the selected sites coupled with the weather parameters in Babylon Governorate (precipitation, temperature, solar, and evapotranspiration) for a 12-year period covering 2005 to 2016. The results from both of the suggested landfill designs showed an absence of leachate from the bottom liner. Validerad;2018;Nivå 2;2018-01-22 (rokbeg)

The landfill design is necessary to be implemented in various regions to protect public human health and the factors ofenvironment. The suggested design of landfill was performed in the arid areas, where that Babylon Governorate, Iraq was selected as a case study. Babylon overnorate is located in the middle of Iraq. The suggested design for the selected sites for landfill in the arid areas was consisted of the base liner and final cover systems. The HELP 3.95D model was applied on both systems to check if there is any leakage by leachate from the suggested soil layers of landfill base on the water balance in Babylon Governorate for the years 2005-2016. The suggested design of final cover system was implemented based on weather parameters in the arid areas through storing water that coming from the surface within upper layers that have fine particles and over the top barrier without leakage into the waste body, thereby preventing leachate generation. This is allowing to the stored water to evaporate from the surface of soil or transpire through vegetation due to the high temperature during the most months in the study area. The results showed there was no percolation of leachate through the base liner system. The design of final cover system was acted to reduce the runoff on the surface and increase theactual evaporation. Validerad;2019;Nivå 1;2019-03-08 (oliekm)