mod1 Flashcards
1
Q
Pure Uniform Compressions
A
volume change with no distortion (change in shape)
2
Q
Pure Shear
A
distortion without any volume change
3
Q
Plane strain conditions
A
when no shearing or deformation occurs in one of our three dimensions
4
Q
Mohr-Coulomb Failure Criterion
A
- drained analysis
- coarse grained soils
5
Q
strength
A
- the ability of the soil to resist shear stress
6
Q
interparticle friction
A
the source of soil’s ability to resist shear stress
7
Q
c’
A
cohesion
- found as a result of fitting experimental peak strength data
- implies soil has some shear strength at zero effective stress
- this apparent strength c’ at zero effective stress does not exist
8
Q
initially dense soils
A
- peak strength higher than their ultimate (critical state)
- sample dilates (decreases in density) during shearing
9
Q
initially loose soils
A
- no peak in strength observed as it takes a good deal of straining to fully mobilise
- sample contracts (increases in density) as it shears
10
Q
the lower the initial void ratio
A
the larger its peak strength
11
Q
the larger the normal stress
A
the lower its peak strength
12
Q
Tresca failure criterion
A
- total stress analysis (undrained loading)
13
Q
Sands and Gravels
A
- relatively permeable
- pore water can be quickly expelled or drawn in
- minimal excess pore pressure is developed and effective stress doesn’t change
- typically DRAINED
14
Q
Clays
A
- small pore sizes restrict drainage
- water can only be expelled or drawn in very slowly
- short term = UNDRAINED
- long term = DRAINED (however this may take decades)
