Potential leakage paths at the dams constructed on karst terrains in Iran

2021 ◽  
pp. qjegh2021-102
Author(s):  
Morteza Mozafari ◽  
Ezzat Raeisi
Keyword(s):  
Karst Aquifer ◽  
Significant Risk ◽  
Grout Curtain ◽  
Engineering Project ◽  
Reservoir Water ◽  
Initial Stage ◽  
Project Failures ◽  
Karst Terrains ◽  
Effective Design ◽  
Hydrogeological Information

Water leakage has been reported from several dams constructed on karst terrains in Iran. In this study the main reasons for dam leakage were identified by studying ten examples, the Lar, Kowsar, Seymareh, Tangab, and Shah-Ghasem dams with considerable leakage, and the Karun I, Karun III, Karun IV, Salman-Farsi, and Marun dams with negligible leakage. The “Potential Leakage Passage (PLP)” is defined as those parts of a karst aquifer which transfer reservoir water to downstream. The most important control on leakage is in the narrowest part of the PLP, the “bottleneck” that depends mainly on the geological settings. At the dams with negligible leakage, sealing of the PLPs was found to be technologically and economically feasible by connecting all the edges of grout curtain to the natural impermeable barriers. In the cases of dams with considerable leakage, wider PLPs were not completely sealed and the installed grout curtain did not fully connect to the impermeable rock. To reduce the risk of leakage and inform effective design of grout curtains, the characteristics of the PLP should be determined during the initial stage of dam studies, and incorporate geological and hydrogeological information in the ground model. This study highlights the significant risk of engineering project failures that can occur if hydrogeological conditions are not properly assessed, understood and managed early in development of dam location, design and construction.

scholarly journals The Monitoring-Based Analysis on Deformation-Controlling Factors and Slope Stability of Reservoir Landslide: Hongyanzi Landslide in the Southwest of China

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Bing Han ◽  
Bin Tong ◽  
Jinkai Yan ◽  
Chunrong Yin ◽  
Liang Chen ◽  
...  
Keyword(s):  
Water Level ◽  
Water Pressure ◽  
Monitoring Program ◽  
Significant Risk ◽  
Controlling Factors ◽  
Seepage Water ◽  
Reservoir Water ◽  
Reservoir Water Level ◽  
Reservoir Area ◽  
Reservoir Landslide

Reservoir landslide is a type of commonly seen geological hazards in reservoir area and could potentially cause significant risk to the routine operation of reservoir and hydropower station. It has been accepted that reservoir landslides are mainly induced by periodic variations of reservoir water level during the impoundment and drawdown process. In this study, to better understand the deformation characters and controlling factors of the reservoir landslide, a multiparameter-based monitoring program was conducted on a reservoir landslide—the Hongyanzi landslide located in Pubugou reservoir area in the southwest of China. The results indicated that significant deformation occurred to the landslide during the drawdown period; otherwise, the landslide remained stable. The major reason of reservoir landslide deformation is the generation of seepage water pressure caused by the rapidly growing water level difference inside and outside of the slope. The influences of precipitation and earthquake on the slope deformation of the Hongyanzi landslide were insignificant.

scholarly journals The possible negative consequences of underground dam and reservoir construction and operation in coastal karst areas: an example of the hydro-electric power plant (HEPP) Ombla near Dubrovnik (Croatia)

2013 ◽  
Vol 13 (8) ◽  
pp. 2041-2052 ◽  
Author(s):  
T. Roje-Bonacci ◽  
O. Bonacci
Keyword(s):  
Power Plant ◽  
Electric Power ◽  
Karst Aquifer ◽  
Grout Curtain ◽  
Negative Consequences ◽  
Karst Spring ◽  
Coastal Karst ◽  
Underground Dam ◽  
The Mean ◽  
Annual Discharge

Abstract. The Ombla Spring represents a typical abundant coastal karst spring located in the vicinity of the town of Dubrovnik (Croatia). Its outlet is at an altitude of 2.5 m above sea level (m a.s.l.) and the water from it immediately flows into the Adriatic Sea. The minimum and maximum measured discharges are 3.96 m3 s−1 and 117 m3 s−1, respectively. The Trebišnjica River traverses through its catchment. The mean annual discharge, after the canalization of over 60 km of its watercourse with spray concrete (in the time span 1981–2011), is 24.05 m3 s−1. Before massive civil engineering work which took place during 1968–1980, the mean annual discharge was 28.35 m3 s−1. There is a project for construction of the hydro-electric power plant (HEPP) Ombla, which will exclusively use groundwater from the Ombla Spring karst aquifer. The underground dam will be constructed about 200 m behind the existing karst spring outflow in the karst massif, by injecting a grout curtain. The top of the grout curtain is planned to be at an altitude of 130 m a.s.l. This karst system is complex, sensitive, vulnerable and ecologically extremely valuable. The grout curtain, as well as the HEPP Ombla development, could lead to extremely dangerous technical and environmental consequences. In this paper some probable, negative consequences of the HEPP Ombla construction and development are explained. The HEPP Ombla could result in many large and hard-to-predict negative consequences which are specific for this particular HEPP, for example (1) severe spring discharge change; (2) unpredictable regional groundwater redistribution; (3) threatening of endemic fauna; (4) induced seismicity; (5) induced sinkholes; (6) occurrence of landslides; (7) conflict regarding internationally shared karst aquifers; (8) intensification of karst flash floods; (9) sea water intrusion in coastal karst aquifer; etc.

Basic Study on Parameters to Quantitatively Evaluate Shape Impression

2008 ◽  
Author(s):  
Keiji Takeda ◽  
Hideki Aoyama
Keyword(s):  
Mass Production ◽  
Surface Form ◽  
High Quality ◽  
Basic Study ◽  
Mass Consumption ◽  
Cad Systems ◽  
Improve Design ◽  
Initial Stage ◽  
Effective Design ◽  
Evaluation Parameters

Manufacturing trends are gradually changing from mass production and mass consumption to “production of diverse products in small quantities”. For this reason, design is recognized as an important element with which a customer judges value. In order to employ the designer’s sensitivity and realize high quality designs, CAD systems which can carry out analysis evaluation of design properties quantitatively, and improve design based on the results is required. In the initial stage of designing, designers embody image form by repeating a sketch. In this process, if the form image of a sketch curve can be evaluated quantitatively and the design form image can be controlled based on the evaluation parameters, this will provide effective design support. In this research, we proposed parameters by which the image of sketch form can be evaluated quantitatively, and investigate the tendencies of various curves and curved surface form. We also developed a system which reconstructs design form using the proposed evaluation parameters.

scholarly journals The imperatives of effective project implementation on national infrastructural development: The engineering perspective

2020 ◽  
Vol 1 (2) ◽  
pp. 037-043
Author(s):  
Obi Lawrence E
Keyword(s):  
Due Process ◽  
Infrastructure Development ◽  
Project Implementation ◽  
Engineering Project ◽  
High Quality ◽  
Infrastructural Development ◽  
Project Costs ◽  
Project Failures ◽  
Process Compliance ◽  
Quality Infrastructure

Project implementation has witnessed multifarious challenges ranging from quackery, corruption, project failures, and inflation of project costs to project abandonment. This has led many developing countries to remain in the doldrums of economic development. An effective project implementation is one that involves all relevant professionals and follows the necessary channels of project execution. The research focused on how effective project implementation can affect the infrastructural development in Nigeria. The research revealed that an effective project implementation will add value to infrastructure development through the elimination of abandonment of projects, projects failure, corruption, project delay and quackery. This paper through its research opined that an effective project implementation will improve the national infrastructural development through durability and high quality infrastructure, increased infrastructural serviceability and sustainability, improved value through transparent project execution, due process compliance and productivity enhancement in construction activities. With the results of the research, it is being recommended that projects should be handled by relevant professionals and the various cycles of civil engineering project be allowed to have its uninterrupted course in project execution.

High Arch Dam Reservoir Basin Deformation & Effect on Dam Operating Status

2014 ◽  
Vol 670-671 ◽  
pp. 651-654
Author(s):  
Er Feng Zhao ◽  
Yu Feng Jiang ◽  
Yan Ling Gu
Keyword(s):  
Influence Factors ◽  
Horizontal Displacement ◽  
Element Model ◽  
Water Levels ◽  
Arch Dam ◽  
Monitoring Data ◽  
High Arch Dam ◽  
Engineering Project ◽  
Reservoir Water ◽  
Reservoir Basin

With the development of 300m super-high dams are built in the southwest of China, reservoir water gravity will make the settlement of the reservoir basin, which will make dam tilt upstream. In the paper, reservoir settlement will be studied in-depth on the basis of monitoring data analysis and numerical simulation comprehensively. First, reservoir basin will be sinking with the rising of the upstream water gradually according to level monitoring data. Second, those affect factors of FEM calculation have been explored comparatively, such as displacement modes, element geometry and boundary conditions. Third, reservoir, dam and foundation are integrated into a whole to establish a wide spread finite element model. At last, reservoir deformation and its influence factors are determined through the simulation of the bedrock depth, the extending length of the upstream and downstream and different water levels. Those methods have been applied into an engineering project and analysis results show that the settlement of the reservoir will make high arch dam tilt upstream, the higher of the water level, the larger of the horizontal displacement. Accordingly, reservoir deformation should be considered deeply on the appraisement of super-high arch dam operating status in future.

Probabilistic Approach to Predicting Risk in Software Projects Using Software Repository Data

2015 ◽  
Vol 25 (06) ◽  
pp. 1017-1032 ◽  
Author(s):  
Changkyun Jeon ◽  
Neunghoe Kim ◽  
Hoh Peter In
Keyword(s):  
Risk Prediction ◽  
Risk Estimation ◽  
Probabilistic Approach ◽  
Significant Risk ◽  
Project Managers ◽  
Risk Level ◽  
Software Project ◽  
Software Projects ◽  
Software Repository ◽  
Project Failures

Although the factors that need to be focused on for a successful software project appear to be difficult to define, risk management has become one of the key activities for achieving such success because significant risk is involved in each software development phase. Software project failures are often a result of insufficient and ineffective risk information regarding the future. To overcome this, software risk prediction should be performed in advance to allow project managers insight into providing more valuable information for decision making, such as scope coverage, resource allocation, and schedule changes. In this research, we propose a risk prediction model from the perspective of quality using a software repository. We evaluated the risk threat level by mapping some defect attributes that exist in the defect lifecycle, defined their risk threat transition states, and applied a Markov chain for predicting the potential risk level. We evaluated the proposed approach using practical real-industry mobile software projects. The experimental results confirm that our approach is applicable to software threat risk estimation.

scholarly journals Teamwork Distribution: Local vs. Global Software Engineering Project Development Teamwork

2020 ◽  
Vol 15 (18) ◽  
pp. 183
Author(s):  
Ismail Al-Taharwa
Keyword(s):  
Software Engineering ◽  
System Development ◽  
Learning Systems ◽  
Engineering Project ◽  
Global Teamwork ◽  
Development Life Cycle ◽  
Project Failures ◽  
E Learning ◽  
Process Perspective ◽  
Intended Learning Outcomes

Deliverable and course project become the preferred mean to measure learner competency and attainment of intended learning outcomes in IT-fields. Proper setup and evaluation for teamwork projects remains a key challenge for e-learning systems. This study investigates the possibility to improve the early prediction of academic software engineering project failure by treating teamwork differently according to the distribution of teamwork participants. Two configurations of teamwork distribution are considered. In the first configuration, a teamwork may include international participants, but all team participants are affiliated to the same institution, namely local teamwork. In the second configuration, a teamwork may include participants from different institutions, namely global teamwork. Software engineering projects are approached from two distinct perspectives. First, obeying the best practices during the system development life cycle (SDLC), namely, process perspective. Second, characteristics of the final deliverable deployed at each milestone of the SDLC, namely product perspective. A publicly released dataset collected by a designated e-learning environment is leveraged to validate the proposed approach. Results indicate a noticeable variance among local and global distributions. These results puts evidence that the reasons behind software engineering teamwork project failures may vary depending on the distribution of the teamwork, local vs. global. Consequently, it advise to customize e-learning systems differently according to the teamwork distribution.

scholarly journals The possible negative consequences of underground dam and reservoir construction and operation in coastal karst areas: an example of the HEPP Ombla near Dubrovnik (Croatia)

2013 ◽  
Vol 1 (2) ◽  
pp. 1409-1443
Author(s):  
T. Roje-Bonacci ◽  
O. Bonacci
Keyword(s):  
Karst Aquifer ◽  
Grout Curtain ◽  
Negative Consequences ◽  
Karst Spring ◽  
Environmental Consequences ◽  
Coastal Karst ◽  
Underground Dam ◽  
Reservoir Construction ◽  
The Mean ◽  
Annual Discharge

Abstract. The Ombla Spring represents a typical abundant coastal karst spring located in the vicinity of town of the Dubrovnik (Croatia). Its outlet is at an altitude of 2.5 m above sea level (m a.s.l.) and the water from it immediately flows into the Adriatic Sea. The minimum and maximum measured discharges are 3.96 m3 s−1 and 117 m3 s−1, respectively. The Trebišnjica River traverses through its catchment. The mean annual discharge, after the canalization of over 60 km of its watercourse with spray concrete (in the time span 1981–2011), is 24.05 m3 s−1. Before massive civil engineering work which took place during 1968–1980, the mean annual discharge was 28.35 m3 s−1. There is a project for construction of the hydro electric power plant (HEPP) Ombla, which will exclusively use groundwater from the Ombla Spring karst aquifer. The underground dam will be constructed about 200 m behind the existing karst spring outflow in the karst massif, by injecting a grout curtain. Top of the grout curtain is planned to be at an altitude of 130, m a.s.l. This karst system is complex, sensitive, vulnerable and ecologically extremely valuable. The grout curtain planned to be realized, as well as the HEPP Ombla development, could lead to extremely dangerous technical and environmental consequences. In this paper some potential, but very probable, negative consequences of the HEPP Ombla construction and development are explained.

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