Groundwater Fluctuation Simulation in Pagelaran Landslide, Cianjur, Indonesia

Pagelaran is one of area in Southern Part of Cianjur. This area has high susceptibility of landslide. One of landslide in Pagelaran, which happened on December 2014, has destroyed 13 houses and damaged vital road along 200 m. A year later, it started to conduct observation regarding the slope. The research aimed to know the role of groundwater level fluctuation in Pagelaran Landslide. The geometry of slope and its slip surface were determined using Electrical Resistivity Tomography. The actual groundwater level was determined by measuring it from surrounding artesian wells. Parameters angle of friction, cohesion, and unit weight were obtained from laboratory tests toward undisturbed soil samples. These data were used for analyzing the actual slope stability condition. Then it was conducted the simulation of slope stability in accordance with fluctuations of groundwater level. The simulation was done by raising the groundwater level with range of 0.5 m. The results showed that the actual slope stability was in critical condition with the value of safety factor 1.044. It also showed that slope stability waned as rising of groundwater level. The value of safety factor was reduced by an average of 0.034 in each 0.5 m up of groundwater level until it became failure (FS<1) when the groundwater level was 0.95 m above the actual position. Therefore, it can be concluded that the position of groundwater level played a role toward the stability of slope in Pagelaran. The rising 0.5 m of groundwater level position will reduce the slope safety factor by 0.034. The slope will become failure if the position of groundwater level rises by 0.95 meter from the actual position. To prevent the rising of groundwater level in rainy season, which can trigger landslide, it can be attached pipes along the slope body to flow the groundwater through them.

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Analysis of Slope Stability with Imprecise Soil Properties Using Uncertain Sets

Mathematical Problems in Engineering ◽

10.1155/2019/1062347 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Xuejun Zhou ◽

Jie Li ◽

Zhibing Liu ◽

Yi Tang

Keyword(s):

Slope Stability ◽

Soil Properties ◽

Safety Factor ◽

Unit Weight ◽

Membership Functions ◽

Stability Of Slopes ◽

Operational Laws ◽

Layered Slope ◽

The Stability ◽

Parameter Values

There are many uncertainties with respect to the assessment of slope stability, and those associated with soil properties should be given particular attention. The uncertainty theory provides an alternative to treat these uncertainties using parochial cognitive sources. A novel methodology is proposed to evaluate the stability of slopes based on an uncertain set. The soil properties involved in the deterministic methods, i.e., shear strength parameters and unit weight, are expressed as uncertain sets, and their membership functions can be assumed to be triangular or trapezoidal for a homogeneous or two-layered slope, respectively. The parameter values of membership functions are designed according to the means and variations of the soil properties, and then the expected safety factor can be calculated through the operational laws. Two numerical examples including a homogeneous slope and a two-layered slope illustrate the suitability of the proposed methodology. The relationship between the variation in the safety factor and the changes in the soil properties is investigated; moreover, the determination of the parameter values of membership is also discussed.

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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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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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Effect of Slip Surface’s Continuity on Slope Dynamic Stability Based on Infinite Slope Model

Mathematics ◽

10.3390/math7010058 ◽

2019 ◽

Vol 7 (1) ◽

pp. 58

Author(s):

Chuanzheng Liu ◽

Gang Wang ◽

Wei Han

Keyword(s):

Dynamic Stability ◽

Stress Wave ◽

Safety Factor ◽

Slip Surface ◽

Great Influence ◽

Stress Wave Propagation ◽

Surface Model ◽

Infinite Slope ◽

Research Results ◽

The Stability

The slip surface is an important control structure surface existing in the landslide. It not only directly affects the stability of the slope through the strength, but also affects the stress field by affecting the propagation of the stress wave. Many research results have been made on the influence of non-continuous stress wave propagation in rock and soil mass and the dynamic response to seismic slopes. However, the effect of the continuity of the slip surface on the slope dynamic stability needs further researches. Therefore, in this paper, the effect of slip surface on the slope’s instantaneous safety factor is analyzed by the theoretical method with the infinite slope model. Firstly, three types of slip surface model were established, to realize the change of sliding surface continuity in the infinite slope. Then, based on wave field analysis, the instantaneous safety factor was used to analyze the effect of continuity of slip surface. The results show that with the decreasing of slip surface continuity, the safety factor does not simply increase or decrease, and is related to slope features, incident wave and continuity of slip surface. The safety factor does not decrease monotonically with the increasing of slope angle and thickness of slope body. Moreover, the reflection of slope surface has a great influence on the instantaneous safety factor of the slope. Research results in this paper can provide some references to evaluate the stability of seismic slope, and have an initial understanding of the influence of structural surface continuity on seismic slope engineering.

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Modelling the effect of Nature Based Solutions on slope instability

10.5194/egusphere-egu2020-9867 ◽

2020 ◽

Author(s):

Stefano Tinti ◽

Glauco Gallotti ◽

Thomas Zieher ◽

Jan Pfeiffer ◽

Filippo Zaniboni ◽

...

Keyword(s):

Slope Stability ◽

Land Use Planning ◽

Groundwater Level ◽

Numerical Models ◽

Slope Instability ◽

Seismic Load ◽

Technical Parameters ◽

Hydrological System ◽

The Stability ◽

Open Air Laboratories

<p>In the framework of the OPERANDUM (OPEn-air laboRAtories for Nature baseD solUtions to Manage environmental risks) project, modelling the effect of the Nature Based Solutions (NBS) on selected open-air laboratories plays a determinant role. In this work, we focus the attention on the V&#246;gelsberg (Tyrol, Austria) landslide case study, located in the municipality of Wattens. The 0.25&#160;km<sup>2</sup> active part of the slope shows annual movement rates in the order of 3.5-6&#160;cm/a. Recent studies provided evidence that the motion is mainly driven by variations of the groundwater level. The latter are related to prolonged moist periods during which excessive rainfall or snow melt water can infiltrate and act on the geo-hydrological system. With the aim of enhancing the slope stability employing NBS, a detailed analysis of the hydrogeology and the slope characteristics have been carried out, obtaining the required technical parameters describing the involved soil material. Furthermore, a slope stability analysis by means of different numerical models has been performed. Results prove that variations of the groundwater level in the range of 1-2 m can strongly affect the stability of the slope. Thus, specific NBS should aim at reducing the amount of infiltrating water. Examples of such NBS include the adaptation of forest management and land use planning, the introduction and re-activation of drainage channels and the sealing of leaky streams and channels. Beside the effects of the variation of the groundwater level, results have proved that the slope could fail under the action of a moderate seismic load. In this scenario, it is likely that the effects of the NBS would be insufficient to maintain the slope intact.</p>

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A Comparative Study on Locating Critical Slip Surface in 2D and 3D Limit Equilibrium Stability Analysis of Slopes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.1905 ◽

2012 ◽

Vol 446-449 ◽

pp. 1905-1913

Author(s):

Mo Wen Xie ◽

Zeng Fu Wang ◽

Xiang Yu Liu ◽

Ning Jia

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Slip Surface ◽

Limit Equilibrium ◽

Three Dimensional ◽

Slope Stability Analysis ◽

Equilibrium Stability ◽

Critical Slip Surface ◽

Minimum Safety Factor

The Various methods of optimization or random search have been developed for locating the critical slip surface of a slope and the related minimum safety factor in the limit equilibrium stability analysis of slope. But all these methods are based on a two-dimensional (2D) method and no one had been adapted for a search of the three-dimensional (3D) critical slip surface. In this paper, a new Monte Carlo random simulating method has been proposed to identify the 3D critical slip surface, in which assuming the initial slip to be the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is located by minimizing the 3D safety factor of limit equilibrium approach. Based on the column-based three-dimensional limit equilibrium slope stability analysis models, new Geographic Information Systems (GIS) grid-based 3D deterministic limit equilibrium models are developed to calculate the 3D safety factors. Several practical examples, of obtained minimum safety factor and its critical slip surface by a 2D optimization or random technique, are extended to 3D slope problems to locate the 3D critical slip surface and to compare with the 2D results. The results shows that, comparing with the 2D results, the resulting 3D critical slip surface has no apparent difference only from a cross section, but the associated 3D safety factor is definitely higher.

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Search of the Most Dangerous in Slide Slope Stability Analysis Based on Genetic Algorithm

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.2535 ◽

2012 ◽

Vol 166-169 ◽

pp. 2535-2538

Author(s):

Ke Wang ◽

Chang Ming Wang ◽

Fang Qi ◽

Cen Cen Niu

Keyword(s):

Genetic Algorithm ◽

Stability Analysis ◽

Slope Stability ◽

Slip Surface ◽

Limit Equilibrium ◽

Evolutionary Process ◽

Limit Equilibrium Method ◽

Slope Stability Analysis ◽

Equilibrium Method ◽

The Stability

The traditional limit equilibrium method in the analysis of slope stability not only exists some subjective empirical hypothesis that can not meet the equilibrium of force and moment, but also ignores the effects of internal stress and strain on the slope stability. Furthermore, in the stability of the slope evaluation, limit equilibrium method relies too much on experience when hypothesizing the slope slip surface. So that it makes deviation on slope analysis and stability evaluation. This paper is based on simplified Bishop method used to establish the model of slope stability analysis. And it used genetic algorithms to solve the minimum safety factor and the most dangerous slip surface of slope. It was the arithmetic which simulates organisms genetic evolutionary process and it avoided the traditional methods falling into the local extreme value point easily and error propagation leading to convergence. The algorithm had advantages of higher accuracy, quick convergence and applicability. It showed that the genetic algorithm is accurate and reliable in the analysis of slope stability.

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ANALISIS STABILITAS LERENG MENGGUNAKAN SOFTWARE PLAXIS 8.6 DENGAN DINDING PENAHAN TANAH (RETAINING WALL) (STUDI KASUS RUAS JALAN NASIONAL BANDA ACEH-MEDAN STA 83+135 GUNUNG SEULAWAH)

Jurnal Arsip Rekayasa Sipil dan Perencanaan ◽

10.24815/jarsp.v1i3.11768 ◽

2018 ◽

Vol 1 (3) ◽

pp. 76-82

Author(s):

Wihardi Wihardi ◽

Munirwansyah Munirwansyah ◽

Sofyan M. Saleh

Keyword(s):

Slope Stability ◽

Safety Factor ◽

Retaining Wall ◽

Road Construction ◽

Local Area ◽

Traffic Load ◽

Road Infrastructure ◽

The Road ◽

The Stability ◽

Banda Aceh

Road infrastructure is very important and is a key enabler for the economy. If the road infrastructure was damaged or had various problems such as sliding, the movement of goods and passengers will be hampered and delayed to the acceleration of development in the local area. The landslide and movement of groundwater is a problem that often occurs repeatedly on some streets. Therefore, it is necessary to study the strengthening of the slopes at the bottom of the road construction with retaining wall. This study aims to analyze slope stability by getting numbers Safety Factor (FK). The analysis is used to analyze the stability of slopesusing the finite element method with the help of software Plaids, The scope of this review includes the calculation of slope stability at the national road from Banda Aceh - Medan Sta. 83 + 185 Mount Selawah. The results of slope stability analysis on the existing condition by using Plaxis software at the point of a review is not safe (FK 1.25). Thus, it is done handling the retaining wall, installation of anchors. Based on the analysis of slope stability after being given the strengthening of the slopes with a retaining wall and the installation of anchors using Plaxis software under the influence of traffic load in an unsafe condition (FK 1.25). Then additional handling is done by changing the angle of the slope so that the value of the safety factor (FK) 1.25.

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Pengaruh Biopolimer Pada Stabilitas Lereng Swelling soil

Borneo Engineering : Jurnal Teknik Sipil ◽

10.35334/be.v5i3.2099 ◽

2021 ◽

Vol 5 (3) ◽

pp. 307-316

Author(s):

Dewi Amalia ◽

Bagus Guritno ◽

Geni Firuliadhim

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Safety Factor ◽

Soil Type ◽

Analysis Program ◽

Swelling Soil ◽

The Difference ◽

The Stability ◽

Cracked Soil

Many studies have begun to develop the concept of cracked soil. The results of research related to cracked soil are able to answer the irregularities that occur, such as the difference in the results of the stability analysis which is considered safe with the conventional bishop method, while the conditions in the field are landslides. Swelling soil is soil that is susceptible to changes in water content. This type of soil is very prone to cracking. To build infrastructure on the swelling soil type, an improvement must be made, one of which is by mixing the swelling soil with biopolymer. The results of this biopolymer mixing are then modeled in the New Slope Stability Analysis Program (NSSAP) 1.0 which refers to the concept of cracked soil. From the analysis, it was found that the slope safety factor before improvement with biopolymer was 0.305 and the safety factor after improvement with biopolymer was 2.006. From the results of this study, it can be seen that the role of biopolymers in stabilizing swelling soil is quite large, which is around 558%.

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Numerical Simulation Analysis of Slope Instability and Failure of Limestone Mine in Weibei

Advances in Civil Engineering ◽

10.1155/2021/5991348 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Kuiming Liu ◽

Hui Li ◽

Shihui Pang ◽

Meng Mi ◽

Jianping Chen ◽

...

Keyword(s):

Slope Stability ◽

Safety Factor ◽

Simulation Analysis ◽

Slip Surface ◽

Three Dimensional ◽

Stable State ◽

Vertical Displacement ◽

Slope Instability ◽

Shaanxi Province ◽

Geological Disaster

Weibei area is the largest limestone resource area in Shaanxi Province, which is an important boundary to distinguish the climate difference between the south and the north of China, and also a significant ecological safety protection barrier in the northwest of China. The complex geological environment and harsh environment make the mining area have serious geological disaster hidden danger. Based on the site engineering geological data of typical limestone quarry slope in Weibei, this paper constructs a three-dimensional geological model, uses FLAC3D software to simulate excavation, and analyzes the stress and strain law of the quarry slope. SlopeLE software was used to analyze the safety factor of slope stability and the potential slip surface before and after taking reinforcement measures. The results show the following: (1) Limestone is the main rock component of the mine, followed by mudstone. The joint and fissure are developed, the rock mass is broken, and the hidden danger of engineering geological disaster is high. (2) There is a sliding trend in both sides during excavation, and the maximum vertical displacement is 2.1 cm. (3) If the slope is reinforced according to the design scheme, the slope stability safety factor will be increased from 1.062 to 1.203 in a stable state, which greatly improves the stability of the slope and provides a guarantee for human and financial resources.

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