Question

For sand mixed with boulder and gravel and for loam soil, the safe hydraulic gradient should be ___________

(a) 1/15

(b) 1/12

(c) 1/5 to 1/9

(d) 1/8

I have been asked this question during an online interview.

The query is from Seepage Theories in section Seepage Theories and Weirs and Barrages Design of Irrigation Engineering

Answer 1

The correct option is (c) 1/5 to 1/9

To explain: For Micaceous sand, the safe hydraulic gradient is less than 1/15 and for Coarse-grained soil is 1/12. For light sand and mud, the safe hydraulic gradient should be less than 1/8.