For calculation model of slope stability under the dsr technique, the general nonlinear mohrcoulomb mc criterion is used to describe the shear failure of slope. The infinite slope failure mode is an example of an internal stability problem. Slope stability analysis of peat landslides has been undertaken in relatively few cases. Free download slope stability analysis spreadsheet, method of slices slope stability analysis, slope stability analysis software free download, slope stability analysis examples, ordinary method of slices spreadsheet, slope stability analysis methods pdf, factor of safety calculation for slope stability, swedish method of slices example, slope analysis pdf, incoming search terms. A series of seven example slope stability problems for the computer program, utexas, is presented. Apr 28, 2018 swedish circle method, mumbai university solved example.
The term landslide refers to a situation of instability affecting natural slopes and involving large. Slopes in mountainous regions require cohesion 8 undrained short term slope failure in clay. Slope stability evaluations by limit equilibrium and finite. Slope stability analysis by the limit equilibrium method. Slope stability refers to the condition of inclined soil or rock slopes to withstand or undergo movement. This calculator determines the factor of safety for a soil slope. This engineer manual em provides guidance for analyzing the static stability of slopes of earth and rockfill dams, slopes of other types of embankments, excavated slopes, and natural slopes in soil and soft rock. This was applied in the model by selecting all the boundary lines between the mudstone and weathered mudstone unshow the water table, to facilitate. Swedish circle method, stability of slope, mumbai university. Step 3 analyze the stability of the slope if a groundwater phreatic surface is specified in the slope. Ru bbar and shansep soil strength pdf gsz page 2 of 8 3 case 1 ru only in this case, the porewater pressure condition is assumed to be described with an ru of 0. The basic approach is determining a factor of safety. In the lecture part of this course we will discuss a variety of methods of analysis of slope stability and instability.
Choice of slope stability calculation method another important choice, which depends on the means that can be used, is that between a method that models the entire soil mass and a method defined locally, along a fracture surface, for example. Slope stability verification manual deep excavation llc page 11 e. Third, finding the correct method of stability analysis solves only part of the design problem. Excavation slope instability may result from failure to control seepage forces in and at the toe of the slope, too steep slopes for the shear strength of the material being excavated, and insufficient shear strength of subgrade soils. In this video we introduce bishops simplified method and the expression of the factor of safety. Rock slope stability analysis utilization of advanced numerical techniques. The slope stability can be analyse nowadays by using a computer program. Where this has been done, the peat failure is usually treated as a translational planar slide and a simple infinite slope analysis is used to back calculate strength parameters of the slope at the time of failure hendrick, 1990. It also highlights some of the differences in approach to that adopted by the limit equilibrium method of slices.
Global stability with relict slip surface in this scenario, the presence of the relict slip surface was assumed. With the development of cheaper personal computer, finite element method has been increasingly used in slope stability analysis. Taylor 1937 conceived the idea of analyzing the stability of a large number of slopes through a wide range of slope angles and. Rules of thumb and easy method of estimating slope stability geology and soils information needed from site or soils database check appropriate loading conditions seeps, rapid drawdown, fluctuating water levels, flows select values to input for. The limit equilibrium method is the most common approach for analyzing slope stability in both two and three dimensions. The quantitative determination of the stability of slopes is necessary in a number of engineering activities, such as.
Fundamentals and methods presents basic principles for the safe design of constructed or natural earth slopes. Geoslope international ltd, calgary, alberta, canada. It is a slightly modified javascript clone of the slope stability software stabr ver. Trevor orr trinity college dublin convenor tc250sc7eg3.
Evaluation of minimum factor of safety in slope stability analysis. Most critical circle corresponding to critical vertical crack depth based on shortterm stability calculations for example problem b. Internal stability can be assured through project specifications by requiring granular materials. The method of stability analysis used see section 6. The aim of this study is to determine the factor of safety fos of. Slope stability analysis by the limit equilibrium method books. Methods for analysis of slope stability are described and are illustrated by examples in the appendixes. Rear property line setback 21m identified slope hazard area front lot line rear lot line top of bank stability component 16m erosion component 5m development setback component open. To overcome its shortcomings, this paper combined hoekbrown criterion and limit equilibrium method and proposed an equation for calculating the safety factor. Importance of slope stability problem is the reason why so many alternate methods have been developed for evaluating the safety of a slope. Manual em 111021902, department of the army, corps of engineers, washington, dc. It uses the bishop modified andor ordinary method of slices for a 2dimensional setting. Application note slope stability analysis worked example 1 introduction this note describes the typical steps followed in setting up and analysing a slope stability problem with limitstate. Slope stability analyses include static and dynamic, analytical or empirical methods to evaluate the stability of earth and rockfill dams, embankments.
Coe 1994 example allowable tractive forces sheetflow. The stability condition of slopes is a subject of study and research in soil mechanics, geotechnical engineering and engineering geology. Various methods are available for slope stability analysis. Chapter 10 slope stability analysis nysdot geotechnical page 106 january 21, 2014 design manual 10. Slope instability may occur suddenly, as the slope is being excavated, or after the.
Application note slope stability analysis worked example 4. Vertical crack for example problem b shortterm stability computations. Soils and foundations testing experience theory lesson 06 chapter 6 slope stability. The graphics and the pointandclick data input are also very good and makes the program very easy to use. Rock slope stability analysis ubc eoas university of british. Slope stability is the resistance of inclined surface to failure by sliding or collapsing. Example of stability, erosion and development setback components n. Slope failure is the movement of mass on slope falls, slides, flows landslide. For more free video tutorials covering slope stability and soil mechanics.
The example problems consist of 1 a simple slope, 2 an embankment on a very strong foundation, 3 an embankment on a relatively weak foundation, 4 an excavated slope. A slope stability calculation, the be used to calculate approximate factor of safety fos values slip planes whilst changing other the infinite slope method assumes the following. Fhwa nhi06088 6 slope stability soils and foundations volume i 6 3 december 2006 6. The calculator searches the circular slip surface for which the factor of safety is minimal. Designing a stable slope includes field investigation, laboratory investigation, and construction control. Ru bbar and shansep soil strength geoslope international. The calculation of slope stability safety factors is a routine practice. Step 4 analyze the stability of the slope if a groundwater flow calculation is specified first to establish the phreatic surface, and then the stability of the slope is calculated. Surcharge pressures on slope for example problem b shortterm stability computation series no. The purpose of this illustrative example is to show how anchors can be used to improve the stability of a system. Before the calculation of slope stability in these methods, some assumptions, for example, the side forces and their directions, have to be given out artificially in order to build the equations of equilibrium. A common problem encountered in engineering soil mechanics is the stability of soil slopes in frictional materials. Determination of slope safety factor with analytical solution and.
This paper aims an overview on various methods of slope stability on the basis of assumptions, factor of safety calculation, soil conditions, soil types, applicability of output of the method with its limitations. Analyzing slope stability by the limit equilibrium method, a. Chapter 10 slope stability analysis nysdot geotechnical page 1011 january 21, 2014 design manual 10. It is essential that the engineering geologist be intimately familiar with all of these methods because they provide ways of determining, relatively unambiguously, whether a.
Taylors stability number if the slope angle, height of embankment h, the effective unit weight of material, angle of internal friction, and unit cohesion c are known, the factor of safety may be determined. What are the factors that influence slope stability. Slope stability for a cohesive and frictional soil11. Learning outcomes gat the end of this session, the participant will be able to. Calculate the factor of safety f against sliding along the potential failure surface qs. The slopes of embankments and earth dams are examples of finite slopes. The setback gradient line measured from the toe of the slope, or channel assuming the location of the toe remains fixed with time. Nov 04, 2014 for more free video tutorials covering slope stability and soil mechanics. November 1984 with the computer program utexas stephen g. In this example, three slope conditions are analyzed.
Slope stability analysis spreadsheet laobing kaisuo. Comparison with hand calculations geoslope international. Pdf slope stability analysis using limit equilibrium method in. Pdf slope stability analysis using modified felleniuss and. Pdf estimation of slope stability using twoparameter. Application note slope stability analysis worked example. The slope length depends on the height of the dam or embankment. An overall stability situation is where there is loss of overall stability of the ground and associated structures, i. Slope stability for a cohesive and frictional soil 11 1 slope stability for a cohesive and frictional soil 1. The term slope means a portion of the natural slope whose original profile has been modified by artificial interventions relevant with respect to stability. Example application 1 slope stability for a cohesive and.
An overview on methods for slope stability analysis. Chapter 4 slope stability universiti teknologi malaysia. The long slope of the face of a mountain is an example of this type, whereas finite slopes are limited in extent. Swedish circle method, mumbai university solved example. Slope stability analysis is performed to assess the safe design of a humanmade or natural slopes e. It is essential that the engineering geologist be intimately familiar with all of these methods because they provide ways of. Finally, several case studies of slope stability analysis are summarized. Mar 21, 2016 taylors stability number if the slope angle, height of embankment h, the effective unit weight of material, angle of internal friction, and unit cohesion c are known, the factor of safety may be determined. The term landslide refers to a situation of instability affecting natural slopes and involving large volumes of soil.
In this video we introduce bishops simplified method and the. Slope, a limit equilibrium slope stability analysis program, was used. The software in general is very good and ties in well with the way we do things here. Example plot of allowable shear stress unit tractive force for cohesive materials. Application of the finite element method to slope stability. Intro to slope stability analysis r ced engineering. Slope stability is an extremely important consideration in the design and. Bishops simplified method slope stability soil mechanics. Spencer analysis method, homogenous material using the mohr coulomb soil model, a dry slope with no porewater pressure, two sloping anchors, and the entry and exit slip surface option.
Since, ec7 does not have a special provision for the problem of a footing on the crest of slope, the question whether it is a bearing capacity or a slope stability problem remains. How do friction and cohesion work together to stabilize slopes. Potential failure surface parallel to the ground surface assumes gravity is the primary factor. Recall modes of slope failureexplain effects of water on slope stability discuss slope stability circular and block.
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