scholarly journals Stability of Slopes Reinforced with Truncated Piles

2016 ◽  
Vol 2016 ◽  
pp. 1-16
Author(s):  
Shu-Wei Sun ◽  
Fu Zhao ◽  
Kui Zhang
Keyword(s):  
Slip Surface ◽  
Influential Factors ◽  
Point Of View ◽  
Optimum Ratio ◽  
Weak Layer ◽  
Stability Of Slopes ◽  
Engineering Technique ◽  
Shear Strength Reduction Method ◽  
Practical Engineering ◽  
The Stability

Piles are extensively used as a means of slope stabilization. A novel engineering technique of truncated piles that are unlike traditional piles is introduced in this paper. A simplified numerical method is proposed to analyze the stability of slopes stabilized with truncated piles based on the shear strength reduction method. The influential factors, which include pile diameter, pile spacing, depth of truncation, and existence of a weak layer, are systematically investigated from a practical point of view. The results show that an optimum ratio exists between the depth of truncation and the pile length above a slip surface, below which truncating behavior has no influence on the piled slope stability. This optimum ratio is bigger for slopes stabilized with more flexible piles and piles with larger spacing. Besides, truncated piles are more suitable for slopes with a thin weak layer than homogenous slopes. In practical engineering, the piles could be truncated reasonably while ensuring the reinforcement effect. The truncated part of piles can be filled with the surrounding soil and compacted to reduce costs by using fewer materials.

A method for calculating the stability of slopes in ledge and semiledge rocks with a complex slip surface

1979 ◽  
Vol 15 (3) ◽  
pp. 255-259
Author(s):  
Yu. S. Kozlov ◽  
V. I. Lopintsev ◽  
A. B. Fadeev
Keyword(s):  
Slip Surface ◽  
Stability Of Slopes ◽  
The Stability

scholarly journals Theoretical Investigation of the Sliding Instability and Caving Depth of Coal Wall Workface Based on the Bishop Strip Method

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Chao Li ◽  
Tianhe Kang ◽  
Xiaopo Li ◽  
Ligong Li ◽  
Xiaoyu Zhang ◽  
...  
Keyword(s):  
Safety Factor ◽  
Slip Surface ◽  
Critical Slip Surface ◽  
Strip Method ◽  
Coal Wall ◽  
Practical Engineering ◽  
Safety Production ◽  
The Stability ◽  
Mining Height ◽  
Sliding Instability

As mining height increases, the influence of coal wall caving on safety production becomes stronger. There is no systematic and effective method to analyse the risk of coal wall caving and its slip caving depth. First, this paper established the Bishop mechanical model of sliding instability of coal wall, and then it deduced the general equation of a safety factor for every slip surface, which can be used to judge the stability of the coal body on the slip surface. Moreover, taking the 8102 workface in the Wulonghu Mine, China, as an example, this paper evaluated the calculation method of slip surface safety factor in detail and obtained the critical slip surface position and the maximum slip depth of a coal wall. Overall, the results showed that the maximum slip depth based on the Bishop strip method is more consistent with the measured data compared with other methods and thus has strong significance and practical engineering value for selecting the most suitable method and its parameters of regulating coal wall caving.

Numerical Analysis of a Slope Stabilized with Anchors

2012 ◽  
Vol 479-481 ◽  
pp. 841-844 ◽  
Author(s):  
Shu Wei Sun ◽  
Jia Chen Wang ◽  
Zhong Ping Zhang
Keyword(s):  
Reduction Method ◽  
Slip Surface ◽  
Three Dimensional ◽  
Strength Reduction ◽  
Strength Reduction Method ◽  
Interface Elements ◽  
Shearing Resistance ◽  
Shear Strength Reduction Method ◽  
The Stability ◽  
Shear Strength Reduction

The three-dimensional shear strength reduction method is used to evaluate the stability of an idealized slope stabilized with anchors, where the soil-anchor interaction is simulated by zero-thickness three-dimensional interface elements, and the effects of the direction angle, position, spacing on the slope stability are numerical studied. The results show that the reinforcing mechanisms of anchors in slopes are to increase the shearing resistance on the slip surface，and the failure mechanism, predicted by SSR, agrees well with the critical slip circle given by Bishop’s simplified method. The better stabilizing effects can be obtained when the anchors are installed with a small angle between the anchor and the horizontal direction, and slightly closer to the slope toe.

scholarly journals A limit equilibrium analysis of progressive failure in the stability of slopes

1978 ◽  
Vol 15 (1) ◽  
pp. 113-122 ◽  
Author(s):  
K. Tim Law ◽  
Peter Lumb
Keyword(s):  
Slip Surface ◽  
Progressive Failure ◽  
Limit Equilibrium ◽  
Friction Angle ◽  
Soil Mass ◽  
Local Failure ◽  
Equilibrium Analysis ◽  
Stability Of Slopes ◽  
The Stability ◽  
Definition Of

A limit equilibrium method of analysis is proposed for the study of progressive failure in slope stability under a long-term condition. Based on effective stresses, the formulation of the method is derived from consideration of force and moment equilibrium within the soil mass above a prospective slip surface. By dividing the soil mass into a number of vertical slices, recognition of local failure can be made. Once local failure takes place, post-peak strength is assumed to be operative. This then initiates a redistribution of interslice forces and leads to some further local failure. Thus realistic available strengths along the slip surface can be evaluated. This permits the definition of a final safety factor, which is expressed in terms of the actual available reserve of strength. The proposed method has been applied to three well documented case records and encouraging results have been obtained. Based on the assumption that post-peak strengths are given by a friction angle equal to the peak value and a zero cohesion, stability charts have been prepared for design purposes.

A 3D slope stability analysis method assuming parallel lines of intersection and differential straining of block contacts

2002 ◽  
Vol 39 (4) ◽  
pp. 799-811 ◽  
Author(s):  
Muhsiung Chang
Keyword(s):  
Slope Stability ◽  
Factor Of Safety ◽  
Slip Surface ◽  
Limit Equilibrium ◽  
Three Dimensional ◽  
Shear Stresses ◽  
Block System ◽  
Stability Of Slopes ◽  
Sliding Mechanism ◽  
The Stability

A three-dimensional (3D) method of analysis of the stability of slopes was developed based on the sliding mechanism observed in the 1988 failure of the Kettleman Hills landfill slope (Kettleman City, California) and the associated model studies. By adopting a limit equilibrium concept, the method assumes the sliding mass as a block system in which the contacts between blocks are inclined. The lines of intersection of the block contacts are assumed to be parallel, which enables the sliding kinematics. In consideration of the differential straining between blocks, the shear stresses on the slip surface and the block contacts are evaluated based on the degree of shear strength mobilization on these contacts. The overall factor of safety is calculated based on the force equilibrium of the individual blocks and the entire block system as well. Based on comparisons with a series of hypothetical 3D and 2D problems with known solutions, the method was generally found to be accurate in predicting the stability of slopes involving a translational type of sliding failure. For rotational sliding failures in clays, however, the method appears to slightly overestimate the calculated factor of safety; up to as much as 10% in a typical problem examined in this study.Key words: slope stability, 3D method, limit equilibrium, block kinematics, strain incompatibility.

scholarly journals Suboptimal Disturbance Observer Design Using All Stabilizing Q Filter for Precise Tracking Control

Mathematics ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1434 ◽  
Author(s):  
Wonhee Kim ◽  
Sangmin Suh
Keyword(s):  
Design Method ◽  
Industrial Applications ◽  
Point Of View ◽  
Observer Design ◽  
Linear Matrix ◽  
External Disturbances ◽  
Closed Loop Systems ◽  
Control Target ◽  
The Stability ◽  
Unified Index

For several decades, disturbance observers (DOs) have been widely utilized to enhance tracking performance by reducing external disturbances in different industrial applications. However, although a DO is a verified control structure, a conventional DO does not guarantee stability. This paper proposes a stability-guaranteed design method, while maintaining the DO structure. The proposed design method uses a linear matrix inequality (LMI)-based H∞ control because the LMI-based control guarantees the stability of closed loop systems. However, applying the DO design to the LMI framework is not trivial because there are two control targets, whereas the standard LMI stabilizes a single control target. In this study, the problem is first resolved by building a single fictitious model because the two models are serial and can be considered as a single model from the Q-filter point of view. Using the proposed design framework, all-stabilizing Q filters are calculated. In addition, for the stability and robustness of the DO, two metrics are proposed to quantify the stability and robustness and combined into a single unified index to satisfy both metrics. Based on an application example, it is verified that the proposed method is effective, with a performance improvement of 10.8%.

scholarly journals No-z Model for Magnetic Fields of Different Astrophysical Objects and Stability of the Solutions

Data ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Evgeny Mikhailov ◽  
Daniela Boneva ◽  
Maria Pashentseva
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Point Of View ◽  
Accretion Discs ◽  
Wide Range ◽  
Astrophysical Objects ◽  
Alpha Effect ◽  
The Stability ◽  
The Magnetic Field

A wide range of astrophysical objects, such as the Sun, galaxies, stars, planets, accretion discs etc., have large-scale magnetic fields. Their generation is often based on the dynamo mechanism, which is connected with joint action of the alpha-effect and differential rotation. They compete with the turbulent diffusion. If the dynamo is intensive enough, the magnetic field grows, else it decays. The magnetic field evolution is described by Steenbeck—Krause—Raedler equations, which are quite difficult to be solved. So, for different objects, specific two-dimensional models are used. As for thin discs (this shape corresponds to galaxies and accretion discs), usually, no-z approximation is used. Some of the partial derivatives are changed by the algebraic expressions, and the solenoidality condition is taken into account as well. The field generation is restricted by the equipartition value and saturates if the field becomes comparable with it. From the point of view of mathematical physics, they can be characterized as stable points of the equations. The field can come to these values monotonously or have oscillations. It depends on the type of the stability of these points, whether it is a node or focus. Here, we study the stability of such points and give examples for astrophysical applications.

scholarly journals Photoluminescent Coordination Polymers Based on Group 12 Metals and 1H-Indazole-6-Carboxylic Acid

Inorganics ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 20
Author(s):  
Antonio A. García-Valdivia ◽  
Estitxu Echenique-Errandonea ◽  
Gloria B. Ramírez-Rodríguez ◽  
José M. Delgado-López ◽  
Belén Fernández ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Coordination Polymers ◽  
Density Functional ◽  
Free Ligand ◽  
Emission Spectra ◽  
Point Of View ◽  
Theoretical Point ◽  
Fourier Transformed Infrared Spectroscopy ◽  
3D Network ◽  
The Stability

Two new coordination polymers (CPs) based on Zn(II) and Cd(II) and 1H-indazole-6-carboxylic acid (H2L) of general formulae [Zn(L)(H2O)]n (1) and [Cd2(HL)4]n (2) have been synthesized and fully characterized by elemental analyses, Fourier transformed infrared spectroscopy and single crystal X-ray diffraction. The results indicate that compound 1 possesses double chains in its structure whereas 2 exhibits a 3D network. The intermolecular interactions, including hydrogen bonds, C–H···π and π···π stacking interactions, stabilize both crystal structures. Photoluminescence (PL) properties have shown that compounds 1 and 2 present similar emission spectra compared to the free-ligand. The emission spectra are also studied from the theoretical point of view by means of time-dependent density-functional theory (TD-DFT) calculations to confirm that ligand-centred π-π* electronic transitions govern emission of compound 1 and 2. Finally, the PL properties are also studied in aqueous solution to explore the stability and emission capacity of the compounds.

Sign in / Sign up

Export Citation Format

Share Document