To assess the stability of slopes under shortterm often during construction and longterm conditions. Slope stability analysis spreadsheet laobing kaisuo. Html 5capable browser required for graphical output. Types of rock slope failures as shown in figure 151, most rock slope failures can be classified into one of four categories depending on the type and degree of structural control. 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. The graphics and the pointandclick data input are also very good and makes the program very easy to use. Pdf advanced calculations of safety factors for slope.
The setback gradient line measured from the toe of the slope, or channel assuming the location of the toe remains fixed with time. Evaluation of minimum factor of safety in slope stability analysis. Slope stability verification manual deep excavation llc page 14. Determine the factor of safety fs for a soil slope.
An overview on methods for slope stability analysis. Determination of the critical slip surface in slope stability. The unit weight of the soil is 20 knm3, the effective cohesion c is 5 kpa and the effective angle of friction is 30. 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. Detailed pieziometric data at multiple locations and depths within and below the slope will likely be needed. The aims of slope stability analyses are to understand the development and form of natural slopes and the processes responsible for different natural features.
While computational tools have made most graphical methods and charts obsolete, stability charts for slopes are still routinely used in practice. Slope stability calculator last updated 12 dec 2014 requires firefox 3. Pdf slope stability analysis methods danial salajegheh. A guide to the program, including a detailed description of the procedures for input of data and an explanation of. Download spreadsheet to calculate slope stability calculation. The factor of safety equations are written in the same form, recognizing whether moment and or force equilibrium is explicitly satisfied. Salunkhe and others published an overview on methods for slope stability analysis find, read and cite all the research. Stability of finite slopes with plane failure surface o culmanns method. Since, the sample analytical method for bearing resistance calculation in the informative annex d of ec7 does not apply to the case of footing on the crest of the slope, meyerhofs 1957 method will be used.
Slopew can effectively analyze both simple and complex problems for a variety of slip surface shapes, porewater pressure conditions, soil properties, and loading conditions. Application note slope stability analysis worked example. Slope stability evaluation and acceptance standards. Slopew limit equilibrium software for slope stability analysis. Limit equilibrium methodresults of slope stability analysesstatic loading filename. The model domain used for this illustration is shown in figure 1. Application note slope stability analysis worked example 4. Run slope stability analyses and calculate required support force for given fs for the simple infinite slope case, hand calculation is sufficient but better use slope stability software use lpile or similar software that allows input of soil displacements instead of loads calculate soil reaction, deflection, bending moment. It is clear from the results that when the height of reservoir water level decreases from 175 m to 145 m, the difference in the safety factor is only approximately 6% at md and md. This free slope calculator solves for multiple parameters involving slope and the equation of a line. Slope failure is the movement of mass on slope falls, slides, flows landslide. The calculation of slope stability safety factors is a routine practice.
Slope stability is the resistance of inclined surface to failure by sliding or collapsing. Griffiths abstract a footing on the crest of a slope may be considered as either a slope stability or a bearing capacity problem. Comparison with hand calculations geoslope international. The effect of water on cut and fill slope stability is briefly discussed below. Slope stability analysis of the potential failures using appropriate methods for the type of failure identified from the kinematic analysis. The factor of safety with respect to strength f as expressed in equation 11. Verification hand calculations geoslope international. An analysis of stability was applied to a slope, of complex geometry, composed of alternating sandstone and marls using finite elements and limit equilibrium methods. Slope stability analysis by the limit equilibrium method books. An analysis of stability was applied to a slope, of complex geometry, composed of alternating sandstone and marls us ing finite elements and limit equilibrium methods. Comparison of slope stability methods of analysis canadian. What is the factor of safety and how does it apply to slope stability.
A larger slope permeability coefficient is associated with a greater probability of penetration with decreasing water level, which is favorable for slope stability. In what ways does water added to a slope affect its stability. A new computer program for performing slope stability calculations has been developed as part of research project 353 by the center for transportation research at the university of texas. Results of your manual calculation with the help of excell program. Also, explore hundreds of other calculators addressing math, finance, health, fitness, and more. Pdf an overview on methods for slope stability analysis. Calculate the factor of safety f against sliding along the potential failure surface qs. Slope stability analyses and settlement calculations xenaki, doulis and athanasopoulos accompanying files 51. Slope stability is controlled by relief material strength soil water content vegetation. Chapter 4 slope stability universiti teknologi malaysia.
Pdf in slope stability analysis, the limit equilibrium method is usually used to calculate the safety factor of slope based on mohrcoulomb criterion find. Slope stability analysis stability analyses stability analyses were performed on eight cross sections of the proposed midbarataria sediment diversion mbsd to assess the potential for stability concerns or problems along the channel alignment from the inlet system to the western end of the conveyance channel. Chapter 6 slope stability, embankments, and hydraulic failure trevor l. This book describes the stateoftheart methodology for evaluating and analyzing soil strength and the design and stabilization of slopes in soil. Traditional slope stability analysis delivers the safety factor with respect to. Calculation of slope stability by phic reduction ratio between available shear strength and the mobilized shear strength in the limit state of the system 2. Slope stability best slope stability analysis software. Pdf importance of slope stability problem is the reason why so many alternate methods have been developed for evaluating the safety of a slope. Next to gravity, water is the most important factor in slope stability. Advanced calculations of safety factors for slope stability article pdf available in international journal of geotechnical engineering 34. Evaluation of minimum factor of safety in slope stability.
Example application 1 slope stability for a cohesive and. Various methods are available for slope stability analysis. With the development of cheaper personal computer, finite element method has been increasingly used in slope stability analysis. Methods for analysis of slope stability are described and are illustrated by examples in the appendixes. The software in general is very good and ties in well with the way we do things here. Importance of water next to gravity, water is the most important factor in slope stability. European commission joint research centre institute for the protection and security of the citizen. What kinds of rock structures can reduce the stability of slopes. Various excavation condition factors affecting slope stability in open excavation types of soil time during which the excavation is required to be open allowable degree of risk of. Results of geotechnical calculations of the embankment internal slope stability analyses of the embankment under static and seismic loading conditions the internal slope stability analyses for the critical cross section of the examined. Slope stability is the best slope stability analysis software suite around providing complete supported slope analysis. The following table summarizes the methods typically included in slope stability software packages.
Ru bbar and shansep soil strength geoslope international. Stability of slopes for excavations in different soil types. A set of 5 basic slope stability problems, together with 5 variants, was distributed in the australian geomechanics profession and overseas as part of a survey sponsored by acads association for computer aided design, in 1988. Focus is on the principles of limit equilibrium analysis and the appropriate use of computer programs. The method of stability analysis used see section 6. 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. Application of the finite element method to slope stability. Analyzing slope stability by the limit equilibrium method, a. Pdf advanced calculations of safety factors for slope stability. The slope stability probability classification sspc system is a rock mass classification system for slope engineering and slope stability assessment. Global stability with relict slip surface in this scenario, the presence of the relict slip surface was assumed. The objective of this example is to demonstrate the verification calculations. Engineers completing slope stability calculations should be familiar with the assumptions and limitations of the methods selected.
Detailed pieziometric data at multiple locations and depths within and below the slope. Geoslope international ltd, calgary, alberta, canada. Please like and subscribe for an nguyens channel to watch the new videos. These analyses are often completed using slope stability charts and the dsara deterministic stability analysis for road access slope stability program. Moreover, the verification process can increase the analysts confidence and understanding of the software. Pdf soil strength and slope stability semantic scholar. Slope stability evaluations by limit equilibrium and. In some cases, the stability andor durability of the existing embankment fill may be questionable because the fill materials are suspect or because slope instability in the form of raveling, downslope lobes, or slope failures have been observed during the site reconnaissance phase. The stability analysis methods satisfying only moment equilibrium may be affected by manual. Extensive studies have been under taken in this area, and a variety of these methods are. Slope w is formulated based on limit equilibrium theory. The presented geotechnical data have resulted from the geotechnical study implemented by edafomichaniki s.
Among his papers ssmos slope stability analysis by three methods of slices with the hp41 programmable calculator in 1985 and ssis and sschkspreliminary slope stability analysis with the hp41 programmable calculator in. Chapter 10 slope stability analysis nysdot geotechnical page 104 january 21, 2014 design manual 10. The calculation of the safety factors did not note any significant dif. The ph creduction stability analysis is based on an. This type of analysis is also utilized to determine. The normal force equation is of the same form for all methods with the exception of the ordinary method. Firstly, the normal and shear stress relationship of the generalized hoekbrown criterion 2002. A simplified solution for calculating the phreatic line. Slope stability evaluations by limit equilibrium and finite. November 1984 with the computer program utexas stephen g.
Chapter 9 embankments washington state department of. This was applied in the model by selecting all the boundary lines between the mudstone and weathered mudstone unshow the water table, to facilitate. How do friction and cohesion work together to stabilize slopes. To assess the possibility of landslides involving natural or existing engineered.
They are certainly major factors in cut slope stability and in the stability of fill slopes involving both internal and external slope failures. Stability of slopes in open excavation in different soil condition along with the factors that control slope stability in open excavation are discussed. Stability computations with zero pore water pres sures for example problem b. Methods are also presented for checking the results of complex analyses and for presenting results of slope stability analyses. Further, for more complex analyses, the use of multiple methods for comparison is prudent. The paper compares six methods of slices commonly used for slope stability analysis. Determination of the critical slip surface in slope stability analysis muhammad alizadeh naderi submitted to the institute of graduate studies and research in partial fulfillment of the requirements for the degree of master of science in civil engineering eastern mediterranean university august 20 gazimagusa, north cyprus.
Pdf slope stability analysis using limit equilibrium method in. Geo slope international ltd, calgary, alberta, canada. The charts presented here are based on the kinematic approach of limit analysis that leads to a strict lower bound on. Pdf nonlinear shear strength reduction technique in. Define the following a angle of repose, b sensitive soils, c hydrocompacting clays, d groundwater, e quick clays. 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. In the lecture part of this course we will discuss a variety of methods of analysis of slope stability and instability. Most critical circular shear surface from longterm stability computations for example prob lem b when cohesion is neglected crosssection of slope and coordinate axes for example problem c. Civilax is the knowledge base covering all disciplines in civil engineering. Step 3 analyze the stability of the slope if a groundwater phreatic surface is specified in the slope. 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. To exactly implement the nonlinear hoekbrown shear strength reduction in slope stability calculations, three aspects of the problem are considered. Extensive studies have been under taken in this area, and a variety of these methods are available for generalized slip surfaces.
Chapter 10 slope stability analysis nysdot geotechnical page 1011 january 21, 2014 design manual 10. Mar 21, 2016 the aims of slope stability analyses are to understand the development and form of natural slopes and the processes responsible for different natural features. It accepts inputs of two known points, or one known point and the slope. The use of the finite elements in calculations of stability has to overcome the weakness of the traditional methods. First, calculate the factor of safety for a specified slip surface using the method of slices. It is essential that the engineering geologist be intimately familiar with all of these methods because they provide ways of. Theory of slope stability kenneth m cruikshank portland state. The probabalistic sara stability analysis for road access program is still under development. Slope stability analysis slopew is the leading slope stability software for soil and rock slopes. 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.