Question

A soil has voids ratio of 0.78 and critical gradient at which quick sand condition occurs is 0.94. Calculate the specific gravity.

(a) 2

(b) 2.5

(c) 2.67

(d) 2.71

This question was addressed to me in an online interview.

My doubt is from Seepage Pressure and Upward Flow in division Seepage Analysis of Geotechnical Engineering I

Answer 1

Correct choice is (c) 2.67

Easy explanation: Given,

Voids ratio e=0.78

critical gradient ic=0.94

\(i_c=\frac{G-1}{1+e}\)

\(0.94=\frac{G-1}{1+0.78}\)

∴ G=2.67.