Question

The grain size curve of the filter should be parallel to that of ____________

(a) Base materials

(b) Filter

(c) Seepage discharge

(d) All of the mentioned

I had been asked this question in an interview.

Query is from Protective Filters in chapter Drainage and Dewatering of Geotechnical Engineering I

Answer 1

Correct choice is (a) Base materials

The explanation is: As per the criteria given by Terzaghi, the grain size curve of the material should be roughly parallel to that of the base materials.