1.2. Mohr’s Circle Representation

Try these first

1. 1.

   What does qu stand for in soil mechanics?

   Hint

   Think about the test name.

2. 2.

   What is the confining pressure during the unconfined compression test?

   Hint

   Consider the definition of 'unconfined'.

3. 3.

   What is the main purpose of the unconfined compression test?

   • To measure permeability
   • To determine unconfined compressive strength
   • To evaluate soil density

   Hint

   Think about what we measure in soil mechanics.

4. 4.

   True or False: The minor principal stress in an unconfined compression test is always negative.

   • True
   • False

   Hint

   Consider the definition of minor principal stress in this context.

5. 5.

   Given a soil sample with an unconfined compressive strength of 200 kPa, how would the failure point shift if the degree of saturation decreases from 100% to 80%?

   Hint

   Reflect on how saturation affects soil mechanics and strength.

6. 6.

   Construct Mohr's Circle for a soil undergoing unconfined compression where the applied axial stress at failure is 150 kPa. Label all important points and explain their significance.

   Hint

   Make sure to include stress states that indicate shear and failure conditions.