Question

Consider the following statements:
1. Buried service lines should be avoided in an expansive soil region.
2. A swelling pressure less than $20kN/m^2$ is not of much consequence.
3. If soil is not black in colour, it is unlikely to be an expansive soil.
Which of these statements are correct?

• A. 1, 2 and 3
• B. 1 and 2 only
• C. 2 and 3 only
• D. 1 and 3 only

Answer 1

The correct option is B 1 and 2 only

There are a lot of swelling soils which are brown or light coloured, even though most expansive soils are dark in colour.
Swelling pressure of a soil depends on lots of factors such as initial dry density, method of compaction, moisture content, height of specimen, surcharge pressure and nature of pore fluid.
A swelling pressure of less than $20kN/m^2$ is not of much consequence.