Rapid Drawdown in Homogeneous Earth Dam Considering Transient Flow and Suction

The present work intends to demonstrate the advantages of considering transient flow regime in the stability analysis of the upstream slope for the rapid drawdown situation of a homogeneous earth dam. Upstream slope stability evaluations were carried out, considering pore pressure and suction from transient flow analysis while simulating rapid drawdown of the reservoir. The evaluations comprised different geometries of the upstream slope (from 1V:1.1H to 1V:2.5H) and heights varying from 10 m to 50 m, as well as several low permeability materials (SM, SM-SC, SC, ML, ML-CL, CL, MH and CH). In addition, equations relating the safety factor to such slopes or dam height were adjusted to the analysis data, in order to define the minimum slope for a certain dam height or the maximum height for a given upstream slope. The results have shown that, considering the transient flow condition, including suction, within the slope stability analysis of the rapid drawdown situation, increases the safety factor in relation to the simplified analysis that is usually adopted. This also results in much steeper slopes (for a safety factor of 1.1) than the ones recommended by the U.S. Bureau of Reclamation (USBR), suggesting the importance of performing transient flow analysis for rapid drawdown situations and considering its results instability analysis.

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Slope Stability Analysis of Elastic Limit Equilibrium Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.1423 ◽

2013 ◽

Vol 275-277 ◽

pp. 1423-1426

Author(s):

Lin Kuang ◽

Ai Zhong Lv ◽

Yu Zhou

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Slip Surface ◽

Limit Equilibrium ◽

Limit Equilibrium Method ◽

Slope Stability Analysis ◽

Sliding Surface ◽

Tangential Stresses ◽

Equilibrium Method

Based on finite element analysis software ANSYS, slope stability analysis is carried out by Elastic limiting equilibrium method proposed in this paper. A series of sliding surface of the slope can be assumed firstly, and then stress field along the sliding surface is analyzed as the slope is in elastic state. The normal and tangential stresses along each sliding surface can be obtained, respectively. Then the safety factor for each slip surface can be calculated, the slip surface which the safety factor is smallest is the most dangerous sliding surface. This method is different from the previous limit equilibrium method. For the previous limit equilibrium method, the normal and tangential stresses along the sliding surface are calculated based on many assumptions. While, the limit equilibrium method proposed in this paper has fewer assumptions and clear physical meaning.

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The accuracy and efficiency of a reduced-order model for transient flow analysis in gas pipelines

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2010.05.001 ◽

2010 ◽

Vol 73 (1-2) ◽

pp. 13-19 ◽

Cited By ~ 19

Author(s):

M. Behbahani-Nejad ◽

Y. Shekari

Keyword(s):

Transient Flow ◽

Flow Analysis ◽

Reduced Order Model ◽

Gas Pipelines ◽

Order Model ◽

Reduced Order ◽

Transient Flow Analysis

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ANALISIS KESTABILAN LERENG HIGHWALL MENGGUNAKAN METODE BISHOP SIMPLIFIED PADA PIT 13 PT BELAYAN INTERNASIONAL COAL KECAMATAN MARANGKAYU KABUPATEN KUTAI KARTANEGARA

JURNAL GEOCELEBES ◽

10.20956/geocelebes.v5i1.13108 ◽

2021 ◽

pp. 46-54

Author(s):

Muhammad Amin Syam ◽

Heriyanto Heriyanto ◽

Hamzah Umar

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Slope Angle ◽

Stable Condition ◽

Physical And Mechanical Properties ◽

Slope Stability Analysis ◽

Open Pit ◽

Mining Company ◽

Water Saturated

PT Belayan Internasional Coal is an open-pit system mining company, one of its geotechnical activities is the construction of the slopes. Slope stability analysis used the Bishop Simplified method to obtain the value of the dynamic safety factor (≥ 1,1). Currently, the value of the Safety Factor (FK) is an indicator in determining whether the slope is stable or not. The parameters used in the slope stability analysis are the physical and mechanical properties of the rock, namely weight (ɣ), cohesion value (c), and internal shear angle (∅). From the results of dynamic overall slope calculations, the recommended overall slope is constructed with an individual slope angle of 55°, a bench width of 5 meters, a height of 10 meters, and the number of individual slopes of 8 slopes. This design will produce dimensions of the overall slope with 41° slope angle, 80 meters high, and has a dynamic safety factor value of 1,102 with the water-saturated condition. Thus, the slopes are in stable condition.

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Application of Harmony Search Algorithm to Slope Stability Analysis

Land ◽

10.3390/land10111250 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1250

Author(s):

Sina Shaffiee Haghshenas ◽

Sami Shaffiee Haghshenas ◽

Zong Woo Geem ◽

Tae-Hyung Kim ◽

Reza Mikaeil ◽

...

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Search Algorithm ◽

Limit Equilibrium ◽

Harmony Search ◽

Harmony Search Algorithm ◽

Slope Stability Analysis ◽

Unit Weight ◽

Slope Safety

Slope stability analysis is undoubtedly one of the most complex problems in geotechnical engineering and its study plays a paramount role in mitigating the risk associated with the occurrence of a landslide. This problem is commonly tackled by using limit equilibrium methods or advanced numerical techniques to assess the slope safety factor or, sometimes, even the displacement field of the slope. In this study, as an alternative approach, an attempt to assess the stability condition of homogeneous slopes was made using a machine learning (ML) technique. Specifically, a meta-heuristic algorithm (Harmony Search (HS) algorithm) and K-means algorithm were employed to perform a clustering analysis by considering two different classes, depending on whether a slope was unstable or stable. To achieve the purpose of this study, a database made up of 19 case studies with 6 model inputs including unit weight, intercept cohesion, angle of shearing resistance, slope angle, slope height and pore pressure ratio and one output (i.e., the slope safety factor) was established. Referring to this database, 17 out of 19 slopes were categorized correctly. Moreover, the obtained results showed that, referring to the considered database, the intercept cohesion was the most significant parameter in defining the class of each slope, whereas the unit weight had the smallest influence. Finally, the obtained results showed that the Harmony Search algorithm is an efficient approach for training K-means algorithms.

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