Odeometric Test

[soman703]

Dear all,
I have a question regarding Oedometric compression test.

When is failure expected to occur in an oedometric compression test.
Is it when vertical effective stress reaches pre consolidation stress?

What would be stress invariants for oedometric test and what is their physical meaning?
Are they p'=0 and q=0 ?

How are recompression, compression and swelling indeces related each other
in oedometric compression test

and what is their practical meaning and application considering geomechanical model.

For instance: what would happen if recompression index is higher than compression index.

what if its lower.

what if swelling index is equal to recompression index.
What do all these situation mean?

In oedometric stress lateral strains are equal to zero and lateral stresses increase proportionally to
applied vertical stress?

Why axial stress increases and lateral stress increments are zero?

Why axial and lateral stresses are increased for same value during each loading step of the test?
Whats the reason behind it?

 

[Ron]

There is no "failure" in the test itself. Its purpose is to develop a characteristic curve of primary, secondary and tertiary compression of the soil. Some soils do not exhibit all of these characteristics; however, this is where your engineering judgment comes in with deciding tolerable levels of compression for settlement analysis.