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Dam projects require comprehensive studies and a careful implementation process; thus, the causes of the possible failure, during the construction or operation of dams, should be thoroughly investigated. Specifically, geotechnical analysis of seepage, static stability, and seismic stability is essential to be evaluated. Earthquakes shaking imposes...
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... shows the total stress at the maximum storage, and the value of the factor of safety for the front face based on the static stresses is shown in Fig.8. The results obtained from slope stability analysis at the static condition for AlAdhaim Dam are presented in Table 2. The results were compared with the allowable values, as presented in the design guidelines of USACE 2003 [29]. ...Context 2
... shows the total stress at the maximum storage, and the value of the factor of safety for the front face based on the static stresses is shown in Fig.8. The results obtained from slope stability analysis at the static condition for AlAdhaim Dam are presented in Table 2. The results were compared with the allowable values, as presented in the design guidelines of USACE 2003 [29]. ...Similar publications
![Summary of Soil Liquefaction Mitigation Methods [17]](publication/365700251/figure/tbl1/AS:11431281112969440@1673636234522/Summary-of-Soil-Liquefaction-Mitigation-Methods-17_Q320.jpg)
The Palu Earthquake in 2018 has triggered a debris flow incident in Bangga River. As a form of protection for similar disasters, it is planned to construct Sediment Control Structures in the Bangga River. The Bangga River area also has liquefaction potential that needs to be considered to ensure the structure’s stability. This study aims to perform...
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... The practical of evaporation is one of the essential elements of the natural hydrological cycle phenomenon. One of the key components that the decisionmaker needs in order to estimate the agricultural, industrial, and environmental plans as well as the water budget is the depth of evaporation (14)(15)(16)(17)(18). Evaporation from bodies of water, such as lakes, can be determined using several direct or indirect methods. ...
One of the hydrological components of the cycle is evaporation, which has actual quantities that are challenging to quantify in the field. As a result, estimations of the evaporation rate's value are made using empirical relationships derived from data on climate components. Several applications of water resources, including hydrological, hydraulic, and an optimal agricultural irrigation system, depend heavily on accurate estimation of evaporation losses. Accurately estimating and forecasting hydrological phenomena is thought to be one of the most critical aspects of managing and developing water resources, as well as creating future water plans that consider various climate change scenarios. The Artificial Neural Network (ANN) and Support Vector Regression (SVR) methods are cutting-edge models that have been employed in several recent research to estimate various hydrological parameters. In the current study, the evaporation rate of Haditha Dam Lake on the Euphrates River in the Al-Anbar Governorate, Iraq, was predicted using ANN and SVR methods. It was designed to receive daily meteorological data, such as temperature, sunshine duration, wind speed, and humidity levels. Evaporation was chosen as the network's output. The present study presented several input scenarios with different input variables to examine the performance of the proposed models. Several statistical indicators have been used to evaluate the prediction results which are root mean square error (RMSE), Nash-Sutcliffe efficiency (NSE), mean absolute error (MAE), and correlation (R 2) the prediction accuracy. The outcomes demonstrated that ANN could predict evaporation value with a high degree of accuracy better than the SVR method. The best prediction model achieved high correlation and mean error between actual and predicted data.
... This analysis underscores the importance of sitespecific soil characterization, as variations in soil properties play a crucial role in assessing seismic risks and foundation stability. Studies such as (Aude et al. 2022), (Audemard et al. 2005), (Ayele et al. 2021), (Chaulagain et al. 2016), (Chenjia et al. 2023, and (Chopra et al. 2012) have similarly emphasized the need for detailed soil analysis in earthquake-prone regions to better understand the potential for soil liquefaction and its impact on infrastructure stability. ...
Water plays a crucial role in the environment and in the process of liquefaction, which can occur during moderate to major earthquakes and cause significant structural damage. Liquefaction is defined as the transformation of granular material from a solid state to a liquid state, a process driven by increased pore water pressure and reduced effective stress within the soil. When an earthquake strikes, the shaking causes the pore water pressure between the sand grains to rise, which in turn reduces the contact forces between the grains. As a result, the sand loses its effective shear strength and starts to behave more like a fluid, leading to instability and potential collapse of structures built on such ground. Liquefaction can occur in moderate to major earthquakes, resulting in severe damage to structures. The transformation of granular material from a solid state to a liquid state due to increased pore pressure and reduced effective stress is defined as liquefaction. When this happens, the sand grains lose their effective shear strength and will behave more like a fluid. This phenomenon of dissolution of soil damages trees’ stability and disturbs the formation of the earth’s surface. Liquefaction resistance of soil depends on the initial state of soil to the state corresponding to failure. The liquefaction resistance can be evaluated based on tests on laboratory and in situ tests. For this research, liquefaction resistance using in-field tests based on SPT N values is attempted. Cyclic resistance ratio (CRR) is found based on the corrected N value. About 16 bore logs have been selected for the factor of safety calculation. The factor of safety for soil was arrived at by taking into account of corresponding corrected SPT N values. The liquefaction hazard map is prepared for the moment magnitude of 7.5-7.6 M w. It is also found that the areas close to water bodies and streams have the factor of safety less than unity. The bore log of locations having a factor of safety less than one indicates that up to a depth of about 6 m, very loose silty sand with clay and sand is present, which are defined as medium to fine sand having low field N values.
... Geostudio software has been widely used in Geotechnical Engineering, especially in Dam Engineering, in recent years. Static-dynamic deformation behaviors and seepage analyses of embankment dams can be performed with the help of this software [5][6][7][8]. In 2D analysis, material zones with different geometric shapes and dimensions can be defined for the zoned embankment dam section. ...
One of the most difficult stages of numerical analysis performed with the Finite Element Method (FEM) is to select the number and geometry of finite elements in the geometric model. Finite elements are the parts that form the entire geometry to which physical and mathematical expressions can be applied. In this study, displacement and stress analyses were performed on the selected zoned embankment dam cross-section in the Geostudio Software Sigma/w module, and the effect of the number of quad&triangle elements forming the mesh network on the results was investigated. According to this study, the number of elements in the stress analyses had a negligible effect. In addition, it is suggested that taking the mesh density as 0.017 1/m 2 in the displacement analyses would be sufficient.
... Hydraulic fracturing, cracking, plant roots, and other defects can cause preferred flow paths to develop within compacted earth-fill and the foundation materials. When water flows through these materials, it may erode soil particles, creating a continuous "pipe" between the upstream and downstream sides [1][2][3][4]. The erosion in fractures through the cores of embankment dams is a well-known and very hazardous kind of concentrated leak. ...
... Several studies have shown that approximately 20 to 30 percent of Iraq is covered with gypseous soil [3]. According to [4] [5], some buildings in Iraq have exhibited various patterns of cracks and nonuniform deformations as a result of the solution, followed by the collapse of the underlying gypseous soils. As reported by [6], when soils are initially dry, volume changes that lead to collapse frequently happen in nonplastic or extremely low plasticity soils and are quicker than during consolidation processes. ...
... Additionally, sediment is deposited upstream of the structure, leaving a resource deficiency downstream]4[. Since a large portion of the sediment load comes from the channel's bottom and sides, rivers that flow through soft material often have higher sediment loads than rivers exposed to bedrock [5,6]. ...
Examining river engineering properties and bed erosion is one of the most challenging but crucial issues in river engineering and sediment hydraulics, so preventing erosion and sedimentation is one of the primary goals of river management and prediction of river behavior. This research aims to give hydraulic engineers and decision-makers an accurate and dependable sediment transport equation that could be utilized to govern river engineering and modify river morphology. This study evaluated the carried sediments and their estimated quantity upstream of the Ramadi Barrage on the Euphrates River in the Anbar area of western Iraq. Six formulas, including Yang, Shen, Hung, Ackers and White, Engelund and Hansen, and Bagnold's and Toffaleti's, were used to evaluate the applicability of sediment transport in the study area. The performance of these models was assessed based on the precision of the actual sediment load relative to a specified deviation ratio. The analyses indicated that the Engelund-Hansen formula is the most applicable for this section of the river; that concludes, field data indicated an annual total sediment flow of roughly 1, 536, 337 tons.
... Several studies have shown that approximately 20 to 30 percent of Iraq is covered with gypseous soil [3]. According to [4] [5], some buildings in Iraq have exhibited various patterns of cracks and nonuniform deformations as a result of the solution, followed by the collapse of the underlying gypseous soils. As reported by [6], when soils are initially dry, volume changes that lead to collapse frequently happen in nonplastic or extremely low plasticity soils and are quicker than during consolidation processes. ...
Collapsibility of gypseous soils may cause excessive settlement and severe damage to engineering structures. Many improvement methods have been employed to reduce the collapsibility of these soils, such as by using physical methods or chemical additives. The collapsibility of the improved gypseous soils has conventionally been evaluated by using the odometer test, which may not accurately replicate the field conditions because of the small size of the test specimens. In this research, a laboratory model test of 600x600x600 mm with a model footing of 100x100mm was developed to measure the collapse characteristics of sandy soil with a gypsum content of 37%. The test was first conducted on specimens in the model at three different relative densities. The test was then performed after compacting the top layer of the test specimens [thickness from 50 to 100 mm] to the maximum dry density, as obtained from the Standard Compaction Test. Water treatment sludge was also used to further improve the top compacted layer. The results indicated that the collapsibility settlement reduction factor was 75% when the top layer of 50 mm thickness was compacted to the maximum dry density. Additionally, when the sludge was used with the top layer, the collapsibility settlement reduction factor was 86%.
... When a positive excess pore pressure result (∆u=+) was obtained, there was a low level of soil resistance to liquefaction, as delineated in Figure The pore water pressure, ∆u, is the difference between the total stress path (TSP) and its effective stress (ESP), [32] . The pore water pressure is formed from changes in the total stress ratio [33], such as an increase in pore water pressure to an increase in total stress, called the pore pressure parameter, in an oedometer test on saturated soils. Figure 16 shows soil behavior at effective peak conditions will direct the stress path to a line with a yield internal friction angle of ϕ'peak = 33.78º, ...
... The thickness of the soil layer played an essential role in measuring the liquefiable value. [17] [18] The more incoherent the soil, the larger the voids between soil particles; thus, the ratio of voids in the soil increases. Results and experiments have proven that soil liquefaction increases with the ratio of voids. ...
One of the most crucial aspects of dam construction is stability under a seismic load. The breakdown of the dam could cause a catastrophic effect on downstream areas. For that, the safety of the facilities lies in their stability. Dams must be stable and withstand the loads placed on them. They are national security facilities. Because dam collapse causes unbridled humanitarian, economic, and social disasters, its construction must be scrutinized and strive to reach the best design with the best materials. The researchers sought to conduct several studies to know the dam’s behaviour during earthquakes, the role of their geometric dimensions, and the technical condition of the soil on which the dam was founded or formed. The simulation and the results indicated that the soil liquefaction state should be reduced, and the three-dimensional results should be analyzed to predict the locations and forms of deformations and the ability to deal with them
The Standard Penetration Test (SPT) is a widely recognized method in geotechnical engineering for evaluating soil properties and estimating liquefaction potential. This test provides essential data that inform the design and construction of foundations in seismic regions. However, with advancements in computational tools, software such as LiqIT has emerged, offering enhanced analytical capabilities for predicting soil behavior under seismic conditions. This study aims to explore the correlation between SPT results and the outputs generated by LiqIT software to assess the consistency and reliability of these methods in liquefaction potential evaluation.
A comprehensive analysis was conducted using SPT data from various sites prone to liquefaction, which were then compared with the liquefaction potential predictions by LiqIT. The study examines the relationship between SPT blow counts (N-values) and the factor of safety against liquefaction as calculated by LiqIT. By establishing a correlation, this research seeks to enhance the understanding of the integration of traditional field tests with modern computational tools in geotechnical practice.
The findings reveal that while SPT remains a valuable field test, integrating its results with LiqIT software offers a more detailed understanding of liquefaction risks. The study's results are expected to contribute to the development of more reliable and efficient methods for assessing liquefaction potential in seismic regions, building upon the foundations laid by previous studies (Seed & Idriss, 1971; Idriss & Boulanger, 2006; Skempton, 1986).
