Which one of the following types of soils will usually shrink if drained or if subjected to repeated loading ?
- ANon-cohesive soils
- BCohesive soils
- CPeatCorrect
- DSilts
Solution
Concept
Volume change of peat
Step-by-step solution
1. Peat is highly organic and holds much water. 2. When drained or loaded repeatedly it consolidates and shrinks considerably.
Explanation
Peat and other highly organic soils lose large volumes when water is removed or when they are loaded.
Why the other options are wrong
Non-cohesive soils and silts show small volume change on draining. Cohesive soils shrink on drying but this is not specific to repeated loading.
Shortcut
Peat: very compressible, shrinks on drainage.
Correct answer: C) Peat