6: Slopes Intro Flashcards
What is the equation for risk?
Risk = Hazard x Population (or value) x Vulnerability
We can quantify landslide hazard by the equation landslide hazard = what?
(susceptibility) * (trigger conditions)
What are the three main elements to susceptibility of landslide hazards?
Slope, Geology, Soil Moisture
What are the three main elements to trigger conditions of landslide hazards?
Seismic, Rainfall, Human
Landslide prediction models only have __ to __% success?
15-30%
What is the primary driving force of landslides?
Gravity
What does rotational slide look like, and what is another word for it?
Slump
What does lateral spreading slide look like?
What does block slide look like?
What does cambering look like?
What does a sand run look like?
What does an earth flow look like?
What does debris avalanche look like?
What does rock and debris creep look like?
What five material factors directly relate to landslide risk?
(1) Rock and soil strength (2) Existing fissures (3) Clay mineral composition (4) Particle size (5) Prior history of material
- What four environmental factors directly relate to landslide risk?
Slope angle, water, time, vegetation
Name an additional trigger mechanism other than rainfall, earthquakes or human slope modifications
Changing conditions (such as dry to wet, frozen to warm)
Give an example of human slope modification
Construction or excavation
When and where did the world’s worst dam-related disaster occur?
1963, three years after completion: Vaiont Dam, Northern Italy
What was the trigger of the world’s worst dam-related disaster?
Raised water level in the reservoir and 11 days of heavy rain
What did the preliminary seismic study of the area in which the worlds worst dam-related disaster occurred show?
Rock strength was good
What was the final slide velocity of the 1963 world’s worst dam-related disaster?
~30 m/s
What was the material behavior of the rock surrounding the dam which was home to the world’s worst dam-related disaster?
Clay layers, which had weak points
What was important about the geological history surrounding the dam which was home to the world’s worst dam-related disaster?
Previous slides lowered the strength of the material in the surrounding valley
The ___ ___ in the valley slopes were inadequately measured at the location were the world’s worst dam-related disaster occurred
Pore pressure
