# Geotechnical Engineering I Mcqs

Q:

The equation for the unconsolidated un drainage strength of clay is __________

 A) τ = c + σ tan φ B) τf = ccu + σ tan φcu C) τ = c + σ D) τ = σ tan φ

Answer & Explanation Answer: B) τf = ccu + σ tan φcu

Explanation: The equation for consolidated undrained strength of the preconsolidated clay in terms of total stress can be approximately expressed as τf = ccu + σ tan φcu where, σ is the normal pressure.

70
Q:

If the pore pressure is measured during un-drained stage of the test, the result can be expressed in terms of __________

 A) C’ and φ B) cu C) None of the mentioned D) All of the mentioned

Explanation: Both effective parameters C’ and φ’ can be expressed when pore pressure is measured during un-drained stage of the test.

60
Q:

Negative pore pressure in clay or sand is developed due to __________

Explanation: A negative pore pressure is developed when we apply load on a sample of clay or sand because both sand and clay tends to expand on loading.

58
Q:

The value of pore pressure parameter, at failure for saturated clay is __________

 A) 1.2 to 2.5 B) 2 to 3 C) 0.3 to 0.7 D) 0.7 to 1.3

Explanation: The approximate value of pore pressure parameter at failure for very loose, fine saturated sand, saturated clays is 2 to 3.

51
Q:

Factor affecting pore pressure parameters is ___________

 A) Type of shear B) Temperature C) Nature of the fluid D) All of the mentioned

Explanation: Type of shear, sample disturbance, and environment during shear such as temperature and nature of the fluid are the factors that affect pore pressure parameter.

87
Q:

The change in the pore pressure during an un-drained shear can be explained by ___________

 A) Lateral pressure B) Effective stress C) Pore pressure parameter D) Mohr’s circle

Explanation: The change in the pore pressure due to change in the applied stress, during an un-drained, any be explained in terms of empirical coefficients called pore pressure parameters.

94
Q:

Which of the following cannot be obtained by using un-drained test?

 A) Effective stress failure envelope B) Shear strength C) sensitivity D) All of the mentioned

Explanation: Since only one Mohr circle in terms of effective stresses, is obtained from all un-drained tests, effective stress failure envelope cannot be obtained from this test.

49
Q:

The consolidated-un drained test can be performed in ___________ methods.

 A) 3 B) 2 C) 4 D) 1