Compaction & CBR

Question 1

What does “CBR” stand for in soil testing?

Answer 1

California Bearing Ratio

Question 2

What’s the primary purpose of a compaction test?

Answer 2

Improve soil density

Question 3

What does a compaction test measure in soil?

Answer 3

Density and moisture content

Question 4

The Proctor test is used to determine the maximum density of soil.

Answer 4

True

Question 5

Which method is NOT typically used for field compaction testing?

Answer 5

Proctor Compaction Test

Question 6

What does the term “optimum moisture content” mean in compaction testing?

Answer 6

The moisture content at which soil reaches its maximum dry density.

Question 7

What could happen if a soil layer is compacted at a moisture content far above the optimum?

Answer 7

The soil may be weaker and more prone to deformation under load.

Question 8

How does soil type affect compaction results?

Answer 8

Different soil types (e.g., clay, sand, gravel) have different compaction characteristics and optimal moisture contents.

Question 9

What is the primary purpose of the modified Proctor test compared to the standard Proctor test?

Answer 9

It uses a higher compaction effort, suitable for materials used in heavy construction.

Question 10

What type of soil is likely to have a low CBR value?

Answer 10

Clayey soil (due to its lower bearing capacity and higher moisture sensitivity).