Embankment Dams

Natural dams may fail due to seepage or piping because they have not undergone systematic compaction and they may have high porosities. This may cause seepage through the dam that could potentially lead to failure by internal erosion (piping). In-depth knowledge of the mechanism of the dam failures by seepage or piping and measured data are still lacking. Extensive laboratory experiments are carried out to study enlargement of the pipe due to internal erosion and resulting outflow hydrographs by varying size of initial pipe, lake water level, lake water volume, slope and location of the pipe. This paper highlights limitations of simplified models used to predict outflow hydrograph due to piping failure of the dam based on experimental results and provides data set for the validation of numerical model. Experimental results show that the initial size, slope and location of pipes have significant effects on magnitude and occurrence time of peak discharge.

The main objectives of this study were to determine the susceptibility to suffusion of widely graded, non-plastic glacial till; to identify potential factors influencing susceptibility; and conversely, to determine grading characteristics that potentially eliminate suffusion susceptibility. A laboratory experimental program was performed on 12 non-plastic glacial till specimens. Four were natural glacial tills sourced from the cores of four existing embankment dams in Sweden, and the remaining eight were mixtures based on these tills with adjusted particle size distributions to obtain target gradations. Four specimens failed by suffusion. By comparing against stable specimens, these were characterized by fines content <20 %, sand fraction <25 %, and finer fraction <30 %. Conversely, gradations with higher fines content (> 25 %), which in this study corresponds to finer fraction >35 %, may provide additional limits to suffusion susceptibility of this kind of soil.

The Mosul Dam, one of Iraq’s most significant infrastructural projects, has been the subject of extensive debate and scrutiny, often overshadowed by negative narratives concerning its safety and environmental impact. These narratives overlook the dam’s significant function in creating food and energy and fostering local, regional, and global water cooperation. This article seeks to provide a comprehensive revaluation of the dam’s contributions to water management and diplomatic relations. By systematically addressing the prevalent criticisms, this study highlights the recent renovation works that extended the dam’s lifespan. These works, which will be examined with a quantitative methodology in the study, involved the Iraqi Government, the Kurdish Regional Government, the United States and Italy. These four entities contributed with joint efforts to make the dam safer, forging trust and collaboration on multiple levels. The Mosul Dam serves as a model for international water cooperation, illustrating the potential for large-scale infrastructure projects to contribute to peace and stability. The reassessment provided in this study advocates for a more nuanced understanding of the Mosul Dam, recognizing its pivotal contributions to water security and international cooperation, which are essential for the region’s sustainable development and beyond.

Streszczenie. Podstawowe opracowania Informatycznego Systemu Osłony Kraju, tworzonego na potrzeby zwiększenia bezpieczeństwa ludzi i mienia, mają charakter dwuwymiarowy. Rozwój technologii informacyjnych pozwala na wizualizacje danych przestrzennych z wykorzystaniem systemów GIS 3D. Szczegółowa wizualizacja wymaga jednak integracji danych przestrzennych pochodzących z różnych źródeł -np. z bezpośrednich pomiarów geodezyjnych, danych ze skaningu laserowego, zdjęć lotniczych, ortofotomapy lub innych opracowań fotogrametrycznych -oraz obiektów z różnych baz danych, w szczególności baz topograficznych. W pracy zaprezentowano koncepcję i efekty trójwymiarowej wizualizacji wyników modelowania hydrodynamicznego wezbrań dla fragmentu doliny rzeki Widawy. Wykorzystano numeryczny model terenu pochodzący z lotniczego skaningu laserowego, na który nałożono teksturę w postaci ortofotomapy. Dane przestrzenne uzupełniono trójwymiarowymi modelami budynków i drzew pochodzącymi z ogólnodostępnej kolekcji galerii 3D Google. Dla zbudowanego modelu przestrzennego wykonano wizualizację wyników modelowania hydrodynamicznego. Integrację i wizualizację danych wykonano w oprogramowaniu Arc-GIS, w module ArcScene. Słowa kluczowe: modelowanie hydrodynamiczne, GIS, 3D, ISOK Publikacja została sfinansowana ze środków Narodowego Centrum Nauki przyznanych na podstawie decyzji nr DEC-2011/01/D/ST10/07671

The low-lying coastal Sundarban is one of the prominent landfall area of tropical cyclones in this region, causing signifcant
environmental and socio-economic disruptions. Spatial cyclone vulnerability assessment is essential to identify its impact
on people and fragile ecosystems. This study applied a GIS-based Analytic Hierarchy Process (AHP) to assess the spatial
distribution of tropical cyclones in the Indian Sundarban. In the process of this cyclone vulnerability mapping, altogether
fourteen spatial components were considered, fve each from the physical and social vulnerability and four from the mitigation capacity. Based on each individual factor's proportionate contribution to the cyclone vulnerability, fve-point risk
classes’ frameworks were created. The study identifed a combined physical and social vulnerability map showing most of
the coastal community development (CD) blocks like Sagar, Namkhana, Patharpratima, Basanti, Gosaba, and Hingalganj are
highly vulnerable to tropical cyclones. Interestingly, while the earlier vulnerability map is being integrated with mitigation
capacity, the result is showing that Sagar, Namkhana, Patharpratima, and Basanti have fallen under a low vulnerable zone.
This is due to the presence of adequate mitigation capacity and infrastructural facilities in those CD blocks. On the other
hand, due to the lack of cyclone shelters and health centers, weak communication facilities, and inadequate infrastructure in
the development blocks like Kultali, a large part of Gosaba, Jaynagar I, Jaynagar II, Canning I, Canning II, and small parts
of Patharpratima and Hingalganj have fallen under very high to high vulnerable zones. The fndings can be applied towards
an efcient need assessment tool for the policymakers, to identify where and what kinds of mitigation measures are required.

This paper analyses the complementarities between land productivity and conservation investments in the context of river embankment maintenance in the Indian Sundarbans. The study finds that households whose principal occupation is aquaculture commit more resources to embankment maintenance relative to those in non-aquaculture employment. While conservation efforts are greater in all types of aquaculture plots irrespective of distance from the embankments, such efforts unambiguously decrease for agricultural plots that are located at a distance from the embankments. Private returns to aquaculture are much higher than returns to agriculture, enabling aquaculture households in invest in managing their local public good. However, there is evidence of free riding in canal-based aquaculture when users draw water from a single source. Head-enders with greater wealth as well as intense social networks tend to free-ride while tail-enders with less land holdings contribute more towards canal maintenance. Furthermore, public intervention in embankment maintenance may be crowding out private efforts. Thus, in primarily agricultural areas, productivity-enhancing policies may be more efficient than policies that fully subsidize public good maintenance.

The paper assesses the impact of urbanization on the landform parameters of Ado-Ekiti city. Data were collected directly from the field on variables such as the river channel morphometry, number of potholes,
number of refuse dump sites, depth of foundation exposure, depth of sediment in storm drains, and extent of road width covered with sediment among others. The basic instruments employed for measuring are the tape, a tie-rod, and ranging pole. Analysis of the data using the descriptive method of  frequency counts and percentage ratings showed that the impact of urbanization includes modification of river and stream channels, sedimentation/fragmentation of riparian vegetation, headward advancement of gully and erosion channel, and excavation of the foundations of buildings among others. The paper suggests measures for controlling the various geomorphological impacts of urbanization in the city including channelization of the streams, effective management of slopes, construction of storm drains of adequate number, and hydraulic
capacity and provision of proper waste management measures, among others.

The geology of Anah vicinity is characterized by cropping out of Anah and Euphrates Formations (Oligocene and Lower Miocene in age, respectively), both of them are built up of limestones and dolostones, with clear basal conglomerate between the two formations. Anah anticline, that extends, almost in East-West trend, is the only structural feature in the area, which is dissected by South-North flowing valleys. Some of these valleys exhibit steep knick points along their courses, which attend 25-45 m in height. They are all located along one line, which also extends East-West. These waterfalls which end with deep holes, along the floor of the valleys are good indicators for the Neotectonic activity, in the region.

This research paper focuses on conducting a steady state seepage analysis along with the downstream slope factor of safety using the Modified Bishops method in a poorly compacted earthen embankment and optimizing the same reservoir earthen embankment in a case study located near Sadiyavav village in Junagadh district in Gujarat, India. The study site, situated at 21°32'06.5"N and 70°37'26.7"E, is renowned for its Asiatic lions. The analysis and optimization were performed with a double-textured High-Density Polyethylene (HDPE) Geo-membrane barrier. Previously, designs and numerical solutions proposed homogenous embankments and too poorly compacted with no drainage arrangements, which led to anisotropic conditions within the section and water seeping out, cutting the phreatic line. The paper presents the documented improvements in the factor of safety achieved through the seepage analysis and the optimization of the HDPE Geomembrane barrier. Two improvement techniques were studied using the "Limiting Equilibrium-Finite Element Method" (LS-FEM). The first using (HDPE) Geo-membrane stabilized with gabions, and the second alternative using HDPE Geomembrane with gabions in addition to rock toe. The study results showed improvements in the downstream slope stability for the two alternatives by 3% and 10%, respectively.

Background: Special attention should be given to the seepage in dams since it may cause failure. Seepage is not considered in the total risk factor calculated using the International Commission of Large Dams (ICOLD), the United States Bureau Reclamation (USBR) while the description of the dam seepage condition is given a weightage in the Brazilian method. Methods: Haditha Dam, Iraq, was constructed on varying degrees of limestone beds of the Euphrates and Ana formations. Therefore, seepage from the dam should be continuously monitored and accurately measured. In the present study, a methodology was proposed to overcome the problem of inconsistent seepage data. The inconsistent seepage rates can be replaced by the predicted seepage rates obtained from SEEP/W model. Results: The predicted seepage rates for different water levels in the reservoir of Haditha Dam were found in association (R 2 = 0.96). In addition, the value of mean absolute error (MAE) for the model accuracy was found to be 0.0106. According to the Brazilian index, the weightage for the seepage condition of Haditha dam was in the second category and equal to 3. Conclusion: For Haditha Dam, the seepage data cannot be used in the dam risk assessment since it was inconsistent with gaps, and it can be replaced by the consistent predicted seepage rates predicted by SEEP/W model. Generally, the aging and other dam problems result in increasing seepage rate. This highlights the importance of efficient management that follows resilient monitoring and surveillance programs that ensure dam safety.

Makhool dam (under construction, which is stopped neither to) is located on the Tigris River about 30 km northwest of Baiji town. The reservoir extends to Sharqat vicinity. The exposed rocks within the reservoir area belong to the Fatha and Injana Formations. The former consists of marl, claystone, limestone and gypsum in cyclic nature. Whereas, the latter consists of claystone, siltstone and sandstone, in cyclic nature too. The western limits of the reservoir are bounded by scarps which belong mainly to Makhool and Khanoogah anticlines. Major parts of these scarps suffer from unstable slopes, along them many mass movements are developed. Moreover, the scarps are potential areas for development of mass movements, which will increase after construction of the dam, due to major change in water level. This will consequently change the properties of the exposed rocks and soils in the banks of the reservoir. The expected mass movements will influence on the stability of the dam, especially if they took place together at once. The slopes and scarps of the western limits of the reservoir are divided into five zones. For each zone different characters are mentioned with estimating conditional and average probability of landslides occurrence. Moreover, unique terrain units are defined.

Doroodzan embankment dam is located on Kore River in 100 km distance from Shiraz city, Iran. It is a homogenous 52 m high, 750 m long dam. Seepage from foundation is controlled by a 26 m cutoff wall below the valley ground surface and also by the combination of upstream clay blanket and rows of relief wells near the down-stream toe of the dam. After the first impoundment in 1973 two springs observed on downstream of left abutment which have not been detected in 1954 preliminarily studies and most probably improper grouting of left bank could be blamed. In addition, longitude and transverse cracks was noticed 3to 4 years after the first impounding on the dam crest especially near the left abutment. Doroodzan dam foundation (after 40 m alluvial deposits in river bed) and its abutments consist from limestone with bedding layers filled with clay which has a high potential for leakage and water escaping. Instrumentation of Doroodzan dam consists of 14 stand-pipe piezometers (Gasagrande). Instrumentation data have been scrutinized and analyzed in order to uncover any potential leakage path through dam body or its abutments. The results of these piezometers are compared with seepage numerical analysis which was performed by Geostudio (Seep/W) software. Results uncovered the potential leakage zones. Furthermore, stress-strain numerical analysis with Plaxis-2D software has been performed in order to discover the causes of transverse cracks on crest of Doroodzan dam. Numerical results shown that the transverse cracks are due to the differential settlements in zones which the foundation has steep slope and changed from soil to rock. Also, series equilibrium analysis with Slope/W software is per-formed to investigate the downstream body stability dependency to phreatic water level and other geotechnical parameters.

In this paper, we propose algorithms which preserve energy in empirical mode decomposition (EMD), generating finite $n$ number of band limited Intrinsic Mode Functions (IMFs). In the first energy preserving EMD (EPEMD) algorithm, a signal is decomposed into linearly independent (LI), non orthogonal yet energy preserving (LINOEP) IMFs and residue (EPIMFs). It is shown that a vector in an inner product space can be represented as a sum of LI and non orthogonal vectors in such a way that Parseval&#39;s type property is satisfied. From the set of $n$ IMFs, through Gram-Schmidt orthogonalization method (GSOM), $n!$ set of orthogonal functions can be obtained. In the second algorithm, we show that if the orthogonalization process proceeds from lowest frequency IMF to highest frequency IMF, then the GSOM yields functions which preserve the properties of IMFs and the energy of a signal. With the Hilbert transform, these IMFs yield instantaneous frequencies and amplitudes as functions of tim...

Contribution à l'étude de l'impact du barrage de Garafiri sur la qualité des eaux et les écosytèmes aquatiques du Konkouré (Rép. de Guinée). Promotion 1997-1998 L L J'adresse mes sincères remerciements: t -à tout le personnel de 1'ORSTOM et tout particulièrement à : c . -Monsieur Pascal Kosuth (responsable du programme u bassins tropicaux H) pour m'avoir permis d'effectuer ce stage et pour son attention envers ce projet, cc -Monsieur Jean-Luc Saos (chercheur hydrogéologue ORSTOM affecté en Guinée), pour l'appui qu'il m'a apporté tout au long de cette étude, I -Monsieur Didier Bazzo (géographe ORSTOM), pour son aide, -Monsieur Jacques Lemoalle (planctonologiste ORSTOM) pour les précieux w renseignements qu'il m'a procurés, r ^, a tout le personnel du CNSHB (Conakry, Rép. de Guinée) et spécialement à: -Monsieur Mamadou Oury Bah (chercheur sédimentologue), pour l'aide qu'il m'a i fournie, Sincères remerciements également à Monsieur Christian Chauvin qui a accepté d'être mon tuteur universitaire, pour le temps qu'il m'a accordé et pour ses conseils et à toutes les L personnes que j'ai rencontrées, qui m'ont accordé des entretiens, des conseils ou leur aide. i ANNEXE 7: présentation d'un indice d'intégrité biotique basé Hydn>bioIogio 33 1: 7 I -78. 1996.

Dams in Jordan are exposed to a variety of natural and manmade threats like dams worldwide, but with some peculiar threats due to Jordan's semi-arid climate, steep topography, tectonic activity, especially along the Jordan Rift Valley, position in the turbulent Middle East area, and weak socio-economic situation. In this study, the threats facing the main dams in Jordan are discussed and their sources are defined. The responsible agencies for reducing the threats and eliminating their sources are identified, as long as they are manmade. Natural threats are dealt with as superimposed and Jordan has to adapt to them by taking the necessary protective measures. The study concludes that all dams in Jordan are threatened by climate change and siltation and hence reduction in storage. The quality of stored water in dams, which are used for supplying drinking water such as Al-Wehdah, Wadi Al-Arab, Ziglab, Al-Wala and to a certain extent Al-Mujib is threatened by pollution due to urbanization, agricultural and industrial activities. All dams in Jordan are exposed to sabotage threats, which may negatively affect dams' water quantities and quality. The stability of dams due to engineering failures is observed in the cases of Al-Kafrain, the left abutment of Al-Mujib, the spillway of Wheidi and eventually Al-Wala Dam. The latter was raised based on unique construction technology. The study recommends developing and implementing, as soon as possible, rigorous action plans to eliminate or, minimize the impacts of threats facing dams in Jordan.

Obiekty zabytkowe, z racji swojej wagi historycznej, powinny podlegać stałemu nadzorowi, szczególnie w kontekście oceny stanu ich konstrukcji oraz wyposażenia. Z racji inwazyjności klasycznych, metrologicznych technik pomiarowych (konieczność instalacji znaków kontrolowanych oraz instrumentarium), często poszukiwane są technologie neutralne, których wykorzystanie bazuje głównie na metodach optycznych. W związku z tym, dopuszczalnymi metodami umożliwiającymi pozyskiwanie powtarzalnych odczytów są rozwiązania bazujące na fotogrametrii oraz detekcji zdalnej (np. skanowanie laserowe). Ponadto problemy z dostępnością do stale pojawiających się oznak uszkodzeń konstrukcji (szczeliny i dylatacje) determinują konieczność wykorzystywania w pełni mobilnych technologii pomiarowych. W kontekście tym, autorzy przedstawili możliwości zastosowania nowoczesnych narzędzi modelowania 3D do badania stanu technicznego konstrukcji budowlanych, ze szczególnym uwzględnieniem rozwiązań niskobudżetowych („low-cost”). Prace badawcze prowadzono na obiektach zabytkowego kompleksu Muzeum Zagłębia w Będzinie, gdzie znajduje się: Pałac Mieroszewskich (1702 r.), zamek warowny (1358 r.) wraz z unikalną wieżą średniowieczną, zabytkowa synagoga z początku XIX w., w której zachowały się cenne polichromie a także podziemna trasa turystyczna będąca pozostałością schronu lotniczego z czasów II Wojny Światowej. Szczegółowej analizie poddano wyniki otrzymane za pomocą rozwiązań fotogrametrycznych oraz metrologicznych, budzących coraz większe zainteresowanie w środowisku geodezyjnym. Można wśród nich wymienić: fotomonitoring oraz aplikacje na smartfon lub tablet, które umożliwiają generowanie chmur punktów na podstawie zdjęć. Zbadano również możliwość wykorzystywania danych, pozyskiwanych wymienionymi technikami oraz opracowywanych za pomocą specjalistycznego oprogramowania do modelowania trójwymiarowego w celu wspomagania analiz SHM (structural health monitoring) istotnych w procesie zarządzania ryzykiem. Pomiary eksperymentalne zweryfikowano za pomocą klasycznych technologii geodezyjnych.

This study  investigates the slope  failure that occurred  at a 152.18-acre residential development inKulim.Theunreinforcedslope was  reportedto  be  deemed stablebefore  its failure in the mid-April2023. Continuous pumping activityfor nearby basement construction had been underway for several weeks prior to the failure. To confirm the causality of drawdown effect, the groundwater level was monitored using two piezometer standpipes.The fieldwork investigation confirmed a significant difference in groundwater levels caused by the dewatering activities. By developing a numerical model using Slope/W software, slope stability analysis was  performed  to  assess the  slope  performancebeforeand  after  the  failure, analysing  the impact of dewatering. The findingsrevealed a significant reduction in the factor of safety (FOS) from 1.348 to 1.080, not adheringto the Jabatan Kerja Raya (JKR)’sslope specifications of a minimum FOS of 1.3 for unreinforced soil. The findings alsoconfirmedthe detrimental effect of rapid drawdown on the strength of the slope.To mitigate the slope failure, gabion walls wereproposedas  cost-effective  alternatives.  This  remedial  measure  increased  the  FOS  to  1.612, meeting  JKR  specifications of  a  minimum  FOS  of  1.5 for  reinforced  soil.  The  findings highlight  the  importance  of educating  on groundwater  management  to  enhance  safety  and mitigate similar risks in future projects

At weirs and dams, the spillway flow is a high-velocity turbulent motion operating at very-large Reynolds numbers and physical measurements are challenging. In these high-speed free-surface flows, the upstream flow is not aerated and some air entrainment takes place downstream of the inception of free-surface aeration. The stateof-the-art knowledge in large dam spillway hydrodynamics currently reaches a major knowledge gap because of a lack of detailed quantitative field measurements in both the non-aerated and air-water flow regions. In this contribution, a review of prototype observations and measurements is presented based upon optical data sets conducted between 2010 and 2022 during floods at several large dam spillways in eastern Australia, with a focus on the key requirements for successful optical velocity measurements in high-velocity (prototype) spillway flows. The experience and expertise gained in these studies provide new insights into the operation of large dam spillways and their modelling. The intricacy of field measurement techniques is discussed using the experience at dam spillways during large floods, encompassing optical velocity measurements of spillway hydrodynamics at two structures. Overall, the paper presents current challenges on the modelling of large dam spillway flows.

Halda, one of the major tributaries of the mountainous river Karnaphuli, is well known as the country's only natural carp spawning ground. Naturally fertilized eggs of carps collected from Halda River are hatched in mud-made scoops on the river bank for aquaculture purposes. However, the river habitat is under constant threat due to human interventions like loop cutting, pollution from the paper mill and power plant, blocking natural water flow of larger tributaries by introducing sluice gates, embankments and rubber dam over the river at upstream, as well natural causes like siltation, erosion and climate change impacts. A study is conducted to address the issues of the ecosystem, sustainable management and the flow regulation impacts of dams in the Halda River, although the flow regulation assessments are conducted based on the macroinvertebrate, index-based framework, land-use effects on the hydrology, new indicators development, hydrologic impact assessment, hydrodynamics in dam regulated rivers, surface-water hydrodynamics and regimes of a small mountain stream and wide range of initiatives. In our case, we considered runoff flow, mountainous flow and dams in the rivers are primary parameters for assessment, so based on previous studies we decided to simulate a hydrologic and hydrodynamic model for the dam and without dam scenarios. Major difficulties and challenges for the environmental flow analysis of a river are continuous data availability. In this research, a hydrologic model ArcSWAT has been built to assess the contribution of rainfall on the river discharge to be used as output from the tributaries in the hydrodynamic model Delft3D. The research findings help us to perceive the effect of the dams on fish breeding condition in the river. In order to perform the environment flow analysis of the river, Tennant method has been followed in the study, which is a secure and reliable approach. The flow regulation impacts are assessed for fish habitat and spawning in the river area based on the simulations. Finally, the findings are further analyzed for velocity profiles for dams by building block method for the sustainable aquatic habitat in the Halda River.

The Sinjar Anticline (Mountain) is an outstanding structural and geomorphic feature in the northwestern part of Iraq. The anticline is a double plunging with almost E-W trend dividing the gently rolling plain in which it is developed into two parts, Al-Jazira Plain in the south and Rabi'a Plain in the north. The Sinjar anticline is asymmetrical with steeper northern limb (45-80)° and gentler southern limb (15-25)°, its length is about 80 km, whereas the width ranges between (9.25-12. 5) km. The oldest exposed rocks belong to the Shiranish Formation, whereas the youngest rocks belong to the Fatha Formation. Different geomorphological and structural forms were observed through interpretation of satellite images, geological and topographical maps of different scales, beside field observations. Among those forms are: Abandoned alluvial fans, radial, inclined, and cross-shaped valleys, whale-back shape, wind gaps, and parasitic folds. All these forms are good indications about the lateral growth of the anticline. Neotectonic measurements were carried to estimate the rates of upward and downward movements. These estimations were performed by measuring the elevation of the contact between the Fatha (Middle Miocene) and Injana (Late Miocene) formations at different selected locations on both sides of the anticline.

The Iraqi territory is located in the extreme northeastern part of the Arabian Plate which is in collision with the Iranian (Eurasian) Plate. The collision which is still ongoing has created tens of folds some of them exhibit different types of faults. The exerted compressional forces are believed to be decreasing southwest wards as being far from the collision area. Accordingly, all the existing tectonic and geological maps compiled by different authors and all the existing published articles, reports and books have considered two main tectonic domains in Iraq. The Stable Shelf and Unstable Shelf or Inner Platform and Outer Platform. The contact between these two main divisions follows almost the Euphrates River; towards west of the river is the Stable area and towards east and north is the Unstable area.In the current study, we have recognized tens of different Neotectonic evidences in the Stable part indicating that the area is tectonically not stable. Among those indications are...

The Iraqi Western and Southern deserts are part of the Iraqi Stable Shelf (Inner Platform) that belongs to the Arabian Plate. Therefore, both deserts lack tectonic forms like folds, faults; however, very rarely faults and regional lineaments can be seen in both deserts. Although both deserts are tectonically stable; but tens of Neotectonic indications can be seen everywhere in both deserts. Among those indications are: Straight valleys, perpendicular valley bending&#39;s, sinkholes aligned along straight lines, dislocated valleys, knickpoints within valleys aligned along straight lines, regional lineaments, anomalous valley shapes, trends and types, dissected alluvial fans. We have used existing geological maps of different scales and Esri World Imagery to recognize those Neotectonic indications. All those recognized features are excellent indications that both the Iraqi Western and Southern deserts are tectonically not stable. Accordingly, new terminology is suggested instead of th...

This research paper focuses on conducting a steady state seepage analysis along with the downstream slope factor of safety using the Modified Bishops method in a poorly compacted earthen embankment and optimizing the same reservoir earthen embankment in a case study located near Sadiyavav village in Junagadh district in Gujarat, India. The study site, situated at 21°32'06.5"N and 70°37'26.7"E, is renowned for its Asiatic lions. The analysis and optimization were performed with a double-textured High-Density Polyethylene (HDPE) Geo-membrane barrier. Previously, designs and numerical solutions proposed homogenous embankments and too poorly compacted with no drainage arrangements, which led to anisotropic conditions within the section and water seeping out, cutting the phreatic line. The paper presents the documented improvements in the factor of safety achieved through the seepage analysis and the optimization of the HDPE Geomembrane barrier. Two improvement techniques were studied using the "Limiting Equilibrium-Finite Element Method" (LS-FEM). The first using (HDPE) Geo-membrane stabilized with gabions, and the second alternative using HDPE Geomembrane with gabions in addition to rock toe. The study results showed improvements in the downstream slope stability for the two alternatives by 3% and 10%, respectively.

Le maintien de la qualité optimale de l'eau pour la production de poissons dans les étangs rizipiscicoles constituent un défi majeur pour les pisciculteurs ivoiriens. L'étude visait à caractériser les paramètres physicochimiques et la biomasse algale des eaux des étangs rizipiscicoles d'une ferme utilisant des sous-produits agricoles. Pour ce faire, les paramètres physico-chimiques et la biomasse algale ont été collectés mensuellement dans un barrage et dans quatre étangs rizipiscicoles de grossissement de Oreochromis niloticus. Les résultats ont montré que les eaux des étangs rizipiscicoles étaient faiblement oxygénées et moins transparentes avec une forte conductivité et de matières dissoutes. Ces eaux étaient fortement ou très polluées, mais avaient une bonne aptitude à l'aquaculture. Les moyennes du pH (5,05 à 6,4), de la conductivité (133,98 à 225,58 µS/cm) et de l'oxygène dissous (3,26 à 4,03 mg/l) de l'eau des étangs rizipiscicoles étaient comprises dans les fourchettes favorables pour une meilleure croissance du tilapia. Les teneurs en nitrate et en ammonium étaient significativement plus élevées dans les étangs rizipiscicoles que dans le barrage. La biomasse algale (8408,5 à 56313,5 µg/cl) et la demande biochimique en oxygène (10 à 24,15 mg/l) étaient significativement plus élevées dans l'Etang-4. Ces résultats démontrent l'enrichissement des eaux des étangs rizipiscicoles en sels nutritifs et en microalgues par l'usage sous-produits agricoles, ce qui optimiserait la productivité du poisson et du riz.

Mosul and Haditha Dams are built on relatively weak foundations. Both of these foundations suffer from extensive karsts which had demanded intensive foundation treatment works among other design precautions. The karst forms; however, are of different origins, activities, nature and shapes. The foundation treatment in both dams was done mainly by constructing deep grout curtains along with other secondary grouting works. Reducing uplift pressure under the dam and cutting down on seepage losses were the major considerations in these works. An additional important requirement in Mosul Dam was to reduce the permeability of the rock formation in the foundations to such a low limit that it can stop the dissolution of gypsum beds present there. This objective; unfortunately, failed due to the lithological composition of this foundation and the presence of many brecciated gypsum beds, which could not be treated successfully. This had resulted in a comprehensive grouting maintenance program which continuous up to date with the everlasting danger of dam failure. On the other hand, in Haditha dam no such complication occurs as the dam had its foundations mainly in limestone. Proper investigation and good planning and performance of the grouting works in this dam contributed highly to its success. Selecting the deep grout curtain as anti-seepage measure in Mosul Dam was not a very wise decision and constructing a positive cutoff in the form of diaphragm wall could have been the proper choice. Good and deep understanding of all geological data can contribute to the success of a dam design or, otherwise it may lead to unsafe one.

Mosul and Haditha Dams are the largest dams on the Tigris and Euphrates Rivers in Iraq, respectively. Both dams are of earthfill type and constructed on sedimentary rocks, but have different geological conditions. Both of them suffer from karstification problems. The former; however, suffers from intense karstification, which has endangered the stability of the dam and possible failure. The karstification in both sites is of different origins, types, shapes, sizes and depths, as well as in different rocks and geological formations. In Mosul Dam site, the highly dissolved gypsum beds of the Fatha Formation has formed solution type sinkholes with cavities of different shapes and sizes at different depth; attaining to about 250 m upon which the foundations of the dam are located. In Haditha Dam site, the karstification occur in the limestone beds of the Euphrates Formation, the developed sinkholes are of collapse type with regular shapes; either circular or oval apertures. The thicknes...

The river Tigris flows from Turkey towards Iraq in its northwestern part dissecting the whole Iraqi territory. During 1981– 1986 a very large earth fill dam was constructed, which is Mosul Dam impounding the flow of the Tigris River. It is the largest dam in Iraq and one of the largest in the Middle East. The geological conditions of the dam site and surroundings, however, are not suitable due to thick exposures of the Fatha Formation, which consists of marl, clay, limestone and gypsum. The gypsum and limestone beds are highly karstified causing severe problems to the dam foundation. Mosul dam suffers from serious problems due to the presence of karstified rocks; therefore, the Ministry of Irrigation in Baghdad, decided to construct a protection dam downstream of Mosul Dam; it is called Badush Dam. The geological conditions at Badush Dam site are the same as those at Mosul Dam site, which means the foundations of the dam are located on karstified rocks. Therefore, grouting works wer...

El río Reconquista posee la segunda cuenca fluvial más extensa
dentro del Área Metropolitana de Buenos Aires (AMBA), área que concentra una parte significativa de los problemas socioambientales de la ciudad. Si bien muchas de las transformaciones de las áreas más bajas de la cuenca se llevaron adelante en forma informal, otras fueron objeto de trabajos planificados. El curso del río fue alterado, a partir de rectificaciones, canalizaciones y creación de nuevos brazos. El objetivo del presente trabajo es examinar la principal de esas obras: la represa Roggero, construida en 1972 para el control de inundaciones.
El trabajo adopta una perspectiva histórica que permite poner de relieve, en primer lugar, el rol desempeñado por las asociaciones locales en movimientos vinculados con la transformación y gestión del río y de su cuenca. En segundo lugar, importará dar cuenta de las condiciones ambientales creadas por la represa y atender a los nuevos usos vinculados con el embalse, que actualmente constituye una pieza paisajística estratégicamente ubicada entre la mancha urbana y el área rural. Estas nuevas condiciones permiten poner en cuestión los argumentos en los que se basan estrategias habituales de la renaturalización como la remoción de represas.

List of Symbols D n Particle diameter for which n % in mass of the remaining particles are smaller than that diameter (mm) ε Strain in the pipe (µm/m) ρ r Loading plate settlement in a reinforced test (mm) ρ unr Loading plate settlement in an unreinforced test (mm) σ r Vertical or horizontal stress in a reinforced test (kPa) σ unr Vertical or horizontal stress in an unreinforced test (kPa) σ v Vertical stress (kPa) σ h Horizontal stress (kPa)

Seepage-induced erosion is one of the main reasons leading to the catastrophic failure of earth dams, levees, and dykes. Mitigation measures include grouting or mixing additives with the soil. In the present study, nanoclay (NC) was investigated as an additive for silty sand soil, considering 1 and 1.5 wt.% NC additions, employing curing periods of 1, 7, 14, and 28-days for the soil–NC mixtures. Homogeneous model dams were then prepared by compaction of the unamended and cured -amended soil materials to the same cross-sectional profile in a laboratory flume apparatus. Once the upstream water level had reached the required water depth, the internal erosion process was initiated by opening a 6-mm dia. preformed hole created through the base width of the model dams next to the flume’s glass sidewall panel. To track the entire erosion process, side-view video recordings of the eroding dam cross-section were taken, employing a novel digital image-processing technique (previously developed by the authors) to track the progression of piping that ultimately lead to breach failure occurring. Original experimental results presented herein show the positive effect of the NC addition on erodibility reduction. From the NC content and curing ranges examined, the 1 wt.% NC and minimum 7-day curing period combination were tentatively identified as producing the best improvement in internal erosion resistance for the investigated soil.

A large-scale apparatus was designed and built at the University of Wollongong to evaluate the pull-out strength of rail subballast reinforced with geocells. A series of tests were carried out to investigate the pull-out resistance, mobilised tensile strength (ttensile) and passive strength (tpassive) of a subballastgeocell assembly under a given range of overburden pressure (1 kPa < q < 45 kPa). The interface was held in a vertical alignment to better simulate the interaction between subballast and geocell in accordance with routine track practices. The test results show that the geocell reinforcement provides a considerable degree of passive resistance, where the opening area (OA) and lateral pressure (sn) over the geocell strip are found to be influential factors. A three-dimensional finite element simulation was also conducted. The numerical results show that the tensile strength mobilised in the geocell will increase as the geocell stiffness increases, but causes a reduction in tpassive. A parametric study was also developed to investigate the impact of geocell stiffness and friction coefficient on the passive resistance and mobilised tensile strength. These results indicate that the passive resistance and mobilised tensile strength increase with the increase in overburden pressure (q) and friction coefficient (d).

Mosul and Haditha dams are two large earthfill dams in Iraq constructed on the Tigris and Euphrates rivers, respectively. The two dams were constructed almost at the same period in the mid-eighties of the last century. Both dams suffer from karstification within their foundations. In the former, however, the problem is more severe than the latter. Mosul Dam was constructed on karstified gypsum and limestone beds; different grouting techniques were used, but the works in grouting are still going on to keep the dam as safe as possible as the sealing of the foundation is hampered by the type of geology. Haditha Dam was constructed on karstified limestone and gypsum rocks also. To avoid the effect of the karstification on the safety of this dam, an exceptionally long grout curtain was constructed as foundation treatment work. The length of the grout curtain extended under the earthfill dam and the concrete structures in the river channel and extended beyond the abutments forming left and right sides extensions to cut off water percolation around the dam which could cause the formation of sinkholes. The depths of all parts of the curtain varied following the karstification zones and intensities. The details of both dams are discussed using updated data and relying on the experience of the authors. The current status of both dams is also discussed with some recommendations to keep both dams as safe as possible.

The Euphrates Formation (Early Miocene) is wide spread formations in central western part of Iraq. It consists of basal conglomerate, well bedded, grey, fossiliferous and hard limestones (Lower Member), chalky like dolomitic limestone, white and massive, green marl, and deformed, brecciated dolomitic limestone and well bedded undulated limestone (Upper Member). The thickness of the formation Iraq is 35-110 m. The uppermost part of the Euphrates Formation includes Brecciated Unit. The fragments (size 1 – 3 cm) are semi angular to semi rounded, consist of very finely crystalline, silicified limestone, arranged in systematic form, which is parallel to the deformations and undulations that are present in both the brecciated mass and the overlying Undulated Limestone Unit. These characteristics of the fragments indicate that the breccia is not formed due to break in sedimentation, but it is syn-sedimentary breccia. The genesis and deformation style of the breccia is discussed in this stu...

Dams are engineering structures constructed for different purposes. They are of different sizes, shapes and types. In all cases, many essential studies should be carried out before deciding the location, type and size of the dam. Among those studies is the geological investigations which should be carried out to deduce the geological conditions in the most relevant site, depth of the foundations and their types, cut-off depth, type of the available construction materials, and type of the expected geological hazards. Without proper geological investigations, the siting of a dam will cause serious hazards during construction and during commissioning of the dam. In this study, Mosul Dam case is considered as the consequences of inadequate geological investigations which were carried out by the contractor and supervised by Swiss Consultant. The location of the dam site and its foundations are built over a highly karstified area, where gypsum and limestone beds are exposed and exist deep...

Kabylia is mountainous and coastline region of Algeria. Every year, particularly in the winter, it is affected by landslides displacing an important volume of detritic materials, and causing damages to infrastructures, housing and public facilities. It takes place in geological formations that are particularly favourable to this type of movement, because of the heterogeneity of their facies and the impermeability of some layers. Experience shows that the main cause of the landslides in this region is the combination of several passive and active factors, as geology, morphology, hydrology, climate and anthropic activities. The exceptional rains of winter 2012 triggered a series of landslides in this region, among which the landslide occurred at PK 226+300 of the National Road RN 24, at a place named Assoumeth-Boulimat, Béjaia department, is one of the most spectacular. The landslide caused the collapse of a section of the road of about 120 meters, with a main scarp of about 8 meters. During the firstly time of the field observation, 18 hours, the landslide mass and the road moved 10 meters. This paper describes this landslide triggered by rainfall and unfavourable geological, hydrogeological and geotechnical conditions. The geotechnical study and methodology of stabilization in two phases will be presented and discussed. Stability calculations were conducted to understand the triggering of the landslide.

The paper presents a slope stability analysis of a proposed embankment contained within an abandoned coal mine reclamation project near Sallisaw, Oklahoma. The project involved the use of computer modeling to analyze the slope stability of the earth-filled embankment. The project plans call for mine spoils and silty-clay borrow materials is used to construct a 74,000 cubic yard embankment, which will be used as a water impoundment for a small lake. The embankment, as designed, consists of a central clay core, mine spoils and a silty-clay material cap. The software program Galena was used as a modeling tool for the slope stability analysis of the proposed embankment. Additionally, seven different variations on the embankment's proposed design were modeled. The ultimate goal was to determine the factor of safety (FS) for each variation. Results show that the Galena program provides a higher factor of safety when compared with conventional methods using the Taylor stability chart. The difference in these values is probably attributed to the general assumptions of the Taylor method.

The fish fauna of the Hârtibaciu River has experienced a disrupted connectivity due to the hydrotechnical works and the Brădeni/Retiş Dam located across the Hârtibaciu watercourse being one of this significant obstacles. The newly proposed constructed wetlands can improve the habitat quality for the fish species of conservative interest sampled in the Brădeni/Retiş Dam proximity

Kabylia is mountainous and coastline region of Algeria. Every year, particularly in the winter, it is affected by landslides displacing an important volume of detritic materials, and causing damages to infrastructures, housing and public facilities. It takes place in geological formations that are particularly favourable to this type of movement, because of the heterogeneity of their facies and the impermeability of some layers. Experience shows that the main cause of the landslides in this region is the combination of several passive and active factors, as geology, morphology, hydrology, climate and anthropic activities. The exceptional rains of winter 2012 triggered a series of landslides in this region, among which the landslide occurred at PK 226+300 of the National Road RN 24, at a place named Assoumeth-Boulimat, Béjaia department, is one of the most spectacular. The landslide caused the collapse of a section of the road of about 120 meters, with a main scarp of about 8 meters. During the firstly time of the field observation, 18 hours, the landslide mass and the road moved 10 meters. This paper describes this landslide triggered by rainfall and unfavourable geological, hydrogeological and geotechnical conditions. The geotechnical study and methodology of stabilization in two phases will be presented and discussed. Stability calculations were conducted to understand the triggering of the landslide.

Denti-strip inclusion is a new type reinforcement that consists of conventional strip type reinforcement and vertical inclusions which are installed on the strip in spacing. A series of laboratory model tests were carried out on a physical model of reinforced sloped embankment with strip inclusions and denti-strip inclusions under surcharge. Compared with strip reinforcement, it is found that due to the existence of vertical reinforcing elements which provided passive resistances against shearing and enhanced soil strength, denti-strip inclusions are more effective in improving the ultimate surcharge, reducing the settlement and restricting the lateral displacement of the slope. Furthermore, the shear bands in the embankment reinforced with two-layer inclusions under the condition without cutting of reinforcements are separated into several discontinuous arc bands by the inclusions unlike the single continuous arc in unreinforced embankment; the inclination angles of the shear bands are greater than that of unreinforced embankment and the position of the lower arc is close to the mid-height of embankment.