Soil Mechanics and Foundation Engineering

141. In a deposit of normally consolidated clay

  1. Effective stress increases with depth but water content of soil and undrained strength decrease with depth
  2. Effective stress and water content increase with depth but undrained strength decreases with depth
  3. Effective stress and undrained strength increase with depth but water content decreases with depth
  4. Effective stress, water content and undrained strength decrease with depth

Correct answer: (C)
Effective stress and undrained strength increase with depth but water content decreases with depth

142. In a flow net

  1. Flow lines and equipotential lines cross each other at right angles
  2. Fields are rectangles whose length is twice the breadth
  3. Smaller the dimensions of the field, smaller will be the hydraulic gradient and velocity of flow through it
  4. For homogeneous soil, the curves are smooth and circular

Correct answer: (A)
Flow lines and equipotential lines cross each other at right angles

143. In a liquid limit test, the moisture content at 10 blows was 70% and that at 100 blows was 20%. The liquid limit of the soil, is

  1. 0.35
  2. 0.5
  3. 0.65
  4. None of these

Correct answer: (C)
0.65

144. In a purely cohesive soil, the critical centre lies at the intersection of

  1. Perpendicular bisector of slope and the locus of the centre
  2. Perpendicular drawn at 1/3rd slope from toe and the locus of the centre
  3. Perpendicular drawn at 2/3rd slope from toe and the locus of the centre
  4. Directional angles

Correct answer: (D)
Directional angles

145. In a triaxial compression test when drainage is allowed during the first stage (i. e. application of cell pressure) only and not during the second stage (i.e. application of deviator stress at constant cell pressure), the test is known as

  1. Consolidated drained test
  2. Consolidated undrained test
  3. Unconsolidated drained test
  4. Unconsolidated undrained test

Correct answer: (B)
Consolidated undrained test

146. In active state of plastic equilibrium in a non cohesive soil with horizontal ground surface

  1. Major principal stress is horizontal
  2. Minor principal stress is vertical
  3. Major principal stress is vertical
  4. Minor and major principal stresses are equally inclined to horizontal

Correct answer: (C)
Major principal stress is vertical

147. In hydrometer analysis for a soil mass

  1. Both meniscus correction and dispersing agent correction are additive
  2. Both meniscus correction and dispersing agent correction are subtractive
  3. Meniscus correction is additive and dispersing agent correction is subtractive
  4. Meniscus correction is subtractive and dispersing agent correction is additive

Correct answer: (C)
Meniscus correction is additive and dispersing agent correction is subtractive

148. In non-cohesive soil in passive state of plastic equilibrium

  1. Major principal stress is horizontal
  2. Minor principal stress is vertical
  3. Major principal stress is vertical
  4. Minor and major principal stresses are equally inclined to the horizontal

Correct answer: (B)
Minor principal stress is vertical

149. In the plate loading test for determining the bearing capacity of soil, the size of square bearing plate should be

  1. Less than 300 mm
  2. Between 300 mm and 750 mm
  3. Between 750 mm and 1 m
  4. Greater than 1 m

Correct answer: (B)
Between 300 mm and 750 mm

150. In the triaxial compression test, the application of additional axial stress (i.e. deviator stress) on the soil specimen produces shear stress on

  1. Horizontal plane only
  2. Vertical plane only
  3. Both horizontal and vertical planes
  4. All planes except horizontal and vertical planes

Correct answer: (D)
All planes except horizontal and vertical planes

Page 15 of 35