1.3. Unconfined Compression Strength

Try these first

1. 1.

   What is the unconfined compression strength?

   Hint

   Think about how strong the soil can be when there’s no pressure around it.

2. 2.

   Why is it important to measure unconfined compression strength?

   Hint

   Remember when we talked about foundations!

3. 3.

   What is the value of the minor principal total stress in an unconfined compression test?

   • 100 kPa
   • 0
   • 200 kPa

   Hint

   Recall that ‘unconfined’ means no pressure surrounding the specimen.

4. 4.

   True or False: Unconfined compression strength is an indicator of a soil's ability to support structures.

   • True
   • False

   Hint

   Think back to the importance of unconfined compression tests in construction.

5. 5.

   You have a clay soil sample with an unconfined compression strength of 150 kPa. After testing, you find a moisture increase. Predict how its strength may change, providing reasoning.

   Hint

   Consider the inverse relationship learned in class.

6. 6.

   Explain how performing an unconfined compression test could create differing outcomes in saturated versus unsaturated soils, using specific examples.

   Hint

   Recall our discussions about moisture effects on load-bearing capacity.