Shear strength

Question 1

what engineering applications can shear strength of soil inform?

Answer 1

slope stability, foundation design, liquefaction, bearing capacity, lateral earth pressure on retaining structures

Question 2

principle stress

Answer 2

1 - major
3 - minor
if the shear stress on a plane is zero, the normal stress on that plane is called a principle stress

Question 3

mohr circle

Answer 3

represents all the stress conditions acting at a point along any plane orientation. takes compressive stresses as positive.

Question 4

How does soil stress differ from other engineering materials?

Answer 4

1) shear strength is the main property of interest
2) shear strength is affected by the stresses from surrounding soil mass, pore pressure, and applied loads.

Question 5

What is shear strength affected by

Answer 5

• soil properties (composition, structure)
• loading characteristics (drainage, loading rate)

Question 6

shear strength is a result of

Answer 6

friction, interlocking of particles, possible cementation or bonding of particles

Question 7

Clay soils and dry granular soils features

Answer 7

dry: angle of repose
clay: flocculated (more resistance), dispersed (less resistance)

Question 8

Failure criterion

Answer 8

-models to represent soil shear strength
-based on assumption that soil is a continuum
-compare to asses wether failure will occur

Question 9

cohesion intercept c’

Answer 9

effective stress parameter - captures effects of interlocking, adhesion and bonding

Question 10

phi ‘

Answer 10

angle of shearing resistance or friction angle - captures frictional effects

Question 11

what is shear strength controlled by

Answer 11

soil type, stresses applied, and pore pressure