Consolidated undrained vs unconsolidated undrained test

[fonseh]

Homework Statement

In the consolidated undrained , why there's only increase in pore water pressure due to deviator stress application ? Why in unconsolidated undrained test , why there is both increase in pore water pressure due to deviator stress application (ud) and also uc ?

Homework Equations

The Attempt at a Solution

IMO , in the consolidated undrained , the total pore pressure should be sum of ud and uc ...

 

[CWatters]

Not my field but...

Initially I shared your confusion. The only thing I can see is that in 12:10 there are two phases described. Drainage is allowed in the first phase which is when external chamber pressure is applied. If the chamber is open to allow drainage then pressure inside doesn't/can't build up.

In 2:11 the chamber is sealed when external pressure is applied so the pressure inside can increase.

I might be wrong but that's the only way I could make sense of it.