scholarly journals Comparative analysis of large scale scenario-based landslides hazard zonation maps. A case study in Iasi City, Romania

2017 ◽  
Vol 19 (1) ◽  
pp. 145-154
Author(s):  
COMAN Cristina Magdalena ◽  
MANEA Sanda ◽  
OLINIC Ernest ◽  
BOȚI Ioan
Keyword(s):  
Comparative Analysis ◽  
Safety Factor ◽  
Large Scale ◽  
Deterministic Model ◽  
Hazard Analysis ◽  
Limit Equilibrium ◽  
Stability Factor ◽  
Northwestern Part ◽  
Engineering Software ◽  
Limit Equilibrium Methods

Large-scale landslides hazard analysis is based, among other methods, on the numerical evaluation of the safety factor using physical and mechanical parameters measured in the field. The safety factor is determined as the ratio between the forces acting in the favor of sliding phenomenon and the resistance of the earthen massive. The main purpose of the paper is to create two bi-dimensional models of landslides hazard assessment based on the estimation of the stability factor, under different degrees of soil saturation and considering different scenarios of seismic acceleration. Slope stability analysis allows the simultaneity of two exceptional loads such as saturation and earthquake. The first model follows the methodology provided by the national law. In this case, the safety factor is determined by applying limit equilibrium methods using specific geotechnical engineering software. The second model aims to create a deterministic model for safety factor assessment implemented in a GIS system. This one is based on the infinite slope model. The secondary objectives of the paper are: providing theoretical principles, attaining the comparative analysis between the methodologies mentioned above, identifying the critical points of the created models and the reciprocal validation of the results. The study area is a hilly area located in the NorthWestern part of the Iasi City, Romania. The geotechnical parameters were obtained from the laboratory tests carried out on samples taken from 22 boreholes. The geomorphological parameters resulted from the high quality digital elevation model with 1m resolution. The final maps representing the spatial distribution of the safety factor values are reclassified using a common scale. Similarity analysis of the results indicates a good mutual validation.

Numerical Simulation Method Ascertaining Slope Stabilization Anti-Slippery Pile's Basic Parameters

2012 ◽  
Vol 594-597 ◽  
pp. 222-225
Author(s):  
Wen Juan Feng ◽  
Xiao Dong Ju ◽  
Zheng Sheng Zou
Keyword(s):  
Numerical Simulation ◽  
Safety Factor ◽  
Limit Equilibrium ◽  
Simulation Method ◽  
Simulation Software ◽  
Strength Reduction ◽  
Slope Stabilization ◽  
Limit Equilibrium Methods ◽  
Basic Parameters ◽  
Shear Strength Reduction

Although anti-slide pile take a key position in slope-treating measures, the method of designing is far from perfect. The methods used in actual projects are based on the rigid body limit equilibrium methods. There is a tendency to using numerical methods in the progress of pile-designing. The safety factor of landslide is calculated according to shear strength reduction theory in the numerical simulation software. Using the shearing forces on pile and the safety factor can ascertain the position of anti-slide piles, the area and distance of piles. For numerical simulation can well perform the simulation slope moving and the load on piles and can give a more reasonable designing.

scholarly journals Experimental and Numerical Investigation on the Stability of Loess Embankment Treated by Chemical Solution under Freezing-Thawing Conditions

2021 ◽  
Author(s):  
Hua Liu ◽  
Zelin Niu ◽  
Yuanhong Dong ◽  
Naifei Liu ◽  
Shuocheng Zhang
Keyword(s):  
Shear Strength ◽  
Safety Factor ◽  
Limit Equilibrium ◽  
Solution Concentration ◽  
Chemical Solution ◽  
Compression Index ◽  
Limit Equilibrium Methods ◽  
Novel Method ◽  
The Stability ◽  
Embankment Stability

Abstract In order to study the influence of chemical solution on the stability of loess embankment in seasonally frozen regions, the compression index, shear strength index and embankment safety factor of compacted loess fillings that were treated by different concentrations of chemical solution were analyzed through laboratory test and slope stability analysis program. The experimental results showed that the collapsible coefficients of remolded loess treated by different chemical solution will all increase which comparing the distilled water, and then will change again after freezing-thawing cycles (FTCs). The compression index of undisturbed loess will show regularity with the increase of chemical solution concentration. The shear strength of remolded loess also changed under the chemical solution and FTCs. Besides, simulation of the strength parameters by limit equilibrium methods showed that the safety factor of loess embankment with treatment of solution was significantly higher than that of untreated one, and the FTC would cause a further deterioration. The embankment stability improved after treated by chemical solution without considering seepage of rainwater. These results would provide a novel method to the problem of embankment stability related to environmental condition changes.

The 2001 R.M. Hardy Lecture: The limits of limit equilibrium analyses

2003 ◽  
Vol 40 (3) ◽  
pp. 643-660 ◽  
Author(s):  
John Krahn
Keyword(s):  
Finite Element ◽  
Factor Of Safety ◽  
Slip Surface ◽  
Limit Equilibrium ◽  
Geotechnical Engineering ◽  
Software Tools ◽  
Great Promise ◽  
Engineering Practice ◽  
Stability Factor ◽  
Limit Equilibrium Methods

Limit equilibrium types of analysis have been in use in geotechnical engineering for a long time and are now used routinely in geotechnical engineering practice. Modern graphical software tools have made it possible to gain a much better understanding of the inner numerical details of the method. A closer look at the details reveals that the limit equilibrium method of slices has some serious limitations. The fundamental shortcoming of limit equilibrium methods, which only satisfy equations of statics, is that they do not consider strain and displacement compatibility. This limitation can be overcome by using finite element computed stresses inside a conventional limit equilibrium framework. From the finite element stresses both the total shear resistance and the total mobilized shear stress on a slip surface can be computed and used to determine the factor of safety. Software tools that make this feasible and practical are now available, and they hold great promise for advancing the technology of analyzing the stability of earth structures.Key words: limit equilibrium, stability, factor of safety, finite element, ground stresses, slip surface.

Revisiting the three-dimensional slope stability problem in clay

2012 ◽  
Vol 49 (4) ◽  
pp. 494-498 ◽  
Author(s):  
Fei Cai ◽  
Atsushi Nakamura ◽  
Keizo Ugai
Keyword(s):  
Safety Factor ◽  
Stability Problem ◽  
Limit Equilibrium ◽  
Three Dimensional ◽  
Failure Surface ◽  
Benchmark Problem ◽  
Integral Expression ◽  
Equilibrium Conditions ◽  
Limit Equilibrium Methods ◽  
Force Equilibrium

This note revisits the benchmark problem involving a spherical failure surface in clay, gives an integral expression for the safety factor defined in terms of moments, and points out the mistakes in the solution of Silvestri. An integral expression for the safety factor of three-dimensional simplified Janbu’s method is also presented to facilitate the validation of three-dimensional limit equilibrium methods that satisfy force equilibrium conditions.

Prediction of Safety Factor for Slope Designed with Various Limit Equilibrium Methods

2011 ◽  
Vol 462-463 ◽  
pp. 611-615 ◽  
Author(s):  
Tariq Mohamed ◽  
Anuar Kasa ◽  
Taha Mohd Raihan
Keyword(s):  
Safety Factor ◽  
Fuzzy Inference System ◽  
Fuzzy Inference ◽  
Limit Equilibrium ◽  
Calculated Data ◽  
Unit Weight ◽  
Inference System ◽  
Limit Equilibrium Methods ◽  
Neuro Fuzzy ◽  
The Stability

The purpose of this study is to predict the stability of slope using adaptive neuro fuzzy inference system (ANFIS). Based on limit equilibrium theory, four different methods of analyses, i.e. Morgenstern-Price, Janbu, Bishop and Ordinary were used to calculate the overall safety factor of various slope designs. Neuro-fuzzy inference system was used to map from a given input to an output. Important parameters such as height of slope (H), unit weight of soil (γ), angle of slope (θ), coefficient of cohesion (c) and internal angle of friction (ф) were used as the input parameters while overall safety factor was the output. ANFIS model to predict the stability of the slopes was generated from the calculated data. Results showed that factors of safety predicted using ANFIS agreed well with factors of safety calculated using Limit Equilibrium Methods (LEM).

Progressive Failure of Offshore Slopes due to Construction in Upslope Areas

2015 ◽  
Author(s):  
Rajib Dey ◽  
Bipul Hawlader ◽  
Chen Wang
Keyword(s):  
Large Scale ◽  
Strain Softening ◽  
Progressive Failure ◽  
Limit Equilibrium ◽  
Shear Bands ◽  
Submarine Landslides ◽  
Limit Equilibrium Methods ◽  
Triggering Factor ◽  
Potential Failure ◽  
Clay Layers

Human activities such as construction loading in upslope areas could be a potential triggering factor for many offshore landslides such as the 1979 Nice landslide. Post-slide investigations show that the existence of marine sensitive clay layers might be one of the potential causes of many large-scale submarine landslides. In this paper, a finite element (FE) modeling technique is developed to analyze the failure of a slope in undrained condition. Nonlinear strain softening behaviour of undrained shear strength of marine sensitive clays is incorporated in the FE analysis. Strain localization in narrow zones (i.e. shear bands) could be successfully simulated. The formation of shear bands and their propagation could explain some potential failure mechanisms. The FE results show that large-scale catastrophic failure of submarine slopes might have occurred due to shear band propagation through strain softening clay layers, which cannot be explained using the traditional limit equilibrium methods for slope stability analysis. Effects of different factors, such as thickness of the marine clay layer and its sensitivity, on stability of submarine slope are also examined.

The mid-Paleozoic deformation in the Hazen fold belt, Ellesmere Island, Arctic Canada

1990 ◽  
Vol 27 (10) ◽  
pp. 1359-1370 ◽  
Author(s):  
Eva M. Klaper
Keyword(s):  
Large Scale ◽  
Ellesmere Island ◽  
Small Scale ◽  
Northwestern Part ◽  
Fold Belt ◽  
Southeastern Part ◽  
Lower Paleozoic ◽  
Slip Mechanism ◽  
Fold Belts ◽  
Surface Geology

The mid-Paleozoic deformation of lower Paleozoic subgreenschist-facies sediments of the Hazen fold belt in northern Ellesmere Island is represented predominantly by chevron-style folding. Folded multilayers display cleavage fans suggesting synchronous fold and cleavage formation. Bedding-parallel slip indicates a flexural slip mechanism of folding. The geometry of several large-scale anticlinoria has been interpreted as being due to formation of these structures over detachments and thrust ramps.The constant fold geometry, the parallel orientation of faults and large- and small-scale folds, and the axial-plane foliation are related to a single phase of folding with a migrating deformation front in the Hazen fold belt during the mid-Paleozoic orogeny. The minimum amount of shortening in the Hazen and Central Ellesmere fold belts has been estimated from surface geology to increase from 40–50% of the original bed length in the external southeastern part to 50–60% in the more internal northwestern part of the belts.The convergent, thin-skinned nature of the Hazen and Central Ellesmere fold belts indicates that the postulated transpressive plate motions during the accretion of Pearya did not affect the study area.

Multi-modal natural interaction in game design: a comparative analysis of player experience in a large scale role-playing game

2015 ◽  
Vol 9 (2) ◽  
pp. 105-119 ◽  
Author(s):  
Pedro Alves Nogueira ◽  
Luís Filipe Teófilo ◽  
Pedro Brandão Silva
Keyword(s):  
Comparative Analysis ◽  
Game Design ◽  
Large Scale ◽  
Role Playing ◽  
Natural Interaction ◽  
Player Experience ◽  
Role Playing Game
Sign in / Sign up

Export Citation Format

Share Document