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GATE 2026 CE (CE2) – Question 33

Geotechnical Engineering · Effective stress principle and quicksand condition · 1 mark · Numerical answer

A fully saturated sandy soil deposit has water content 20 % and specific gravity 2.65.

The critical hydraulic gradient for seepage through the soil to create the quicksand condition is _____________ (*rounded off to two decimal places*).

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Correct answer: 1.07 to 1.09

Explanation

For a saturated soil $e = wG = 0.20 \times 2.65 = 0.53$. The critical hydraulic gradient is $i_c = \frac{G - 1}{1 + e} = \frac{1.65}{1.53} = 1.08$.