 Home
 News Center

Publications
 Publications Home
 GeoLiFi
 Online Library
 ISSMGE's Case Histories Journal

Top 10 papers
 Top 10 papers on the Flat Dilatometer
 Top 10 papers on the properties of Municipal SolidWaste
 Top 10 papers on the Cone Penetration Test
 Top 10 Introductory Papers on Macroscopic Soil Plasticity Constitutive Modelling
 Top 10 papers on the Pressuremeter
 Top 10 papers on Embankment Dams
 Top 10 papers on Active Faulting
 Top 10 papers on Surface Wave Analysis for Geotechnical Site Characterization
 Journals
 Magazines
 Featured Books
 Geoeducational Guide 2014
 GEOTECHNICAL TESTING CATALOGUES

Education
 Education Home
 Educational Websites
 History

Webbased Class Projects
 Geoenvironmental Remediation Technologies
 Selected Topics in Ground Improvement
 Rock Mechanics

Geoenvironmental Engineering
 Uranium Mill Tailings Remediation in the United States
 Biodegradation in Municipal Solid Waste landfills
 Sediment Quality Guidelines (SQGs): A Review and Their Use in Practice
 Investigating Soil Remediation Techniques for Military Explosive and Weapons Contaminated Sites
 Soil Remediation Techniques: Examination of In Situ Chemical Oxidation
 Monitoring of waste degradation processes for sustainable MSW landfills
 Landfill Gas Monitoring Systems

Geoenvironmental Engineering Fall 2017
 Seismic Response and Stability Analysis of Landfills
 Brownfield Remediation
 Sampling Techniques for Characterization of Contaminated Sites
 Comparing the Advantages and Limitations of Different Techniques Used to Quantify Methane...
 Electrical Resistivity Tomography for Characterizing Contaminated Sites
 Landfill Leachate Treatment
 End Uses of Landfills
 Deep Well Injections
 Ralph Peck Legacy Website
 James K. Mitchell Legacy Website
 Multimedia
 Networking
 JOBS
 Software
 GeoMap
Seismic Response and Stability Analysis of Landfills
 Seismic Response and Stability Analysis of Landfills
 Landfill Performance
 Case Study of OII
 Seismic Analysis of Landfill
 (1) Site Specific Geological Evaluation
 (2) Dynamic Properties Landfill Waste
 (6) Slope Stability Analysis
 Computer Program Application
 Seismic Design Conclusion
 Seismic Analysis of a Geosynthetic Liner System
 Seismic Response of a Composite Cover (Case study)
 Authors
 References
 All Pages
(6) Slope Stability Analysis
The two conventional approaches to evaluate the stability of landfill structural systems consist of the pseudostatic method of analysis and the Newmark SlidingBlock analysis.
Pseudostatic analysis –
The pseudostatic method gives the limit state equilibrium which produces factor of safety values of slopes during seismic loading. A minimum FS of 1 is desired and essentially means that the driving force is equal to the resisting force since,
FS = 1 = resisting force / driving force
thus, resisting force = driving force if FS = 1
FS = ( ( W * cos(α) – k * W * sin(α) * tan(φ) ) / ( W * sin(α) + k * W * cos(α) )
where k = a_{h} / g
Where,
a_{h} = pseudostatic accelerations in horizontal directions
k = coefficients for horizontal and vertical directions
W = weight of failure mass
g = Earth’s gravitational constant
φ = Friction angle soil property
α = See Figure 1.8
With this said, literature indicates choosing the k coefficients is based on very subjective criteria and descriptions. This can significantly affect the accuracy of this method.
Also, the seismic accelerations exist in the horizontal and vertical directions, however, the horizontal component is the only one considered in design since the vertical forces average out to 0 anyway, thus, becoming insignificant (Kramer,1996).
Figure 1.8: Force diagram depicting a sliding mass on an inclined plan. Force diagram of a landslide mass sitting on an inclined planar slip surface (Terzaghi, 1950).
As per the diagram,
W = weight / unit length of landslide mass
k = seismic coefficient
s = shear resistance along slip surface
α = angle of slip surface inclination
Note in this scenario, the whole landslide mass is considered as a whole, from the toe of the slope to the surface above. This limits our selection and generalizes the failure planes.
Newmark analysis –
The slidingblock analysis was introduced by Nathan Newmark in 1965. The Newmark analysis gives the cumulative, permanent displacement of the slopes during seismic loading. The method utilizes the basic physics scenario of the rigid block on an inclined plane, as shown in Figure 1.9 (Kramer, 1996). Just as there is a certain amount of friction that a wooden block on an inclined surface will need to overcome to be in motion, likewise, the yield acceleration is the acceleration required for the landslide mass to initiate motion, or sliding in this case. The yield acceleration is a_{y} = k_{y}g. When the a_{y} is exceeded, permanent deformation occurs. This method is used to compare between the displacement of the slopes and allowable displacement of the landfill components in the event of a major earthquake. This method is more refined than the pseudostatic method and the end result of this analysis is more applicable to design since it produces a direct physical displacement.
Figure 1.9: Forces acting on a block on an inclined plane in dynamic conditions. (Kramer, 1996)
Figure 1.10: Illustrated the integration of the accelertion above the yield acceleration to render the velocity which is integrated again to obtain the displacement (Krishna, 2009).