BeginnerTopic 39 of 112Civil & Structural
Slope stability
Analyses factor of safety against sliding of embankments and cuts.
In depth
Factor of safety is ratio of resisting to driving forces along a failure surface. Methods: infinite slope, Fellenius/Bishop (method of slices), finite elements. Remedies: flatten slope, drain, buttress, reinforce. Rainfall raising pore pressure is a common trigger.
Key points
- Circular vs planar failure
- Short-term vs long-term stability
- Monitoring with inclinometers
ExampleA road cutting is stabilised with soil nails and drainage.
Slope stability analysis finds whether cuts and embankments will fail, which protects roads, buildings and people below.
What is Slope stability?
Analyses factor of safety against sliding of embankments and cuts.
Why is it important to understand slope stability?
Slope stability analysis finds whether cuts and embankments will fail, which protects roads, buildings and people below.
What is the factor of safety for a slope?
The ratio of the resisting strength to the driving forces along a potential failure surface, and values above one indicate stability.
What triggers slope failure?
Heavy rain, excavation at the toe, loss of strength with time, and earthquakes are common triggers.
How is Slope stability used in practice?
Typical applications include checking the factor of safety of an embankment after a rapid drawdown, designing a cut slope in soft rock with a stable angle and assessing a natural hillside before building a house on it.
What should I learn before Slope stability?
Study "Earth pressure theories" first (topic 38 of 112 in Civil & Structural). It covers the groundwork this topic builds on.
What are the key points of Slope stability?
Circular vs planar failure. Short-term vs long-term stability. Monitoring with inclinometers.
Can you give an example of Slope stability?
A road cutting is stabilised with soil nails and drainage.
What comes after Slope stability?
The next topic is "Ground improvement", which builds directly on this one.
How difficult is Slope stability?
It is classed as Beginner in Civil & Structural (topic 39 of 112). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.