Engineering Geology Multiple Choice Questions on “Causes of Mass Movements –
01”.
1. The factors that cause the failure are generally grouped into how many?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: All the factors that facilitate mass failure in one way or another are generally grouped in two headings: Internal factors and External factors.
2. The causes which tend to reduce the shearing strength of the soil are __________
a) Internal factors
b) External factors
c) Extensive factors
d) Weather factors
Answer: a
Clarification: Internal factors include such cases, which tend to reduce the shearing strength of the soil or rock mass by virtue of which it had remained stable at a given position on the ground.
3. Nature of slope includes __________
a) Type of material and angle of mass
b) Mass of material and type of material
c) Type of material and shape of mass
d) Mass of material and angle of mass
Answer: a
Clarification: The nature of slope includes two important characters of the slope. By nature of slope is meant here the type of material of which the land mass is made up and the angle at which this particular mass is inclined with the horizontal.
4. The force which helps to retain the position of mass in space is __________
a) Compressive resistance
b) Tensile resistance
c) Shearing resistance
d) Bending resistance
Answer: c
Clarification: The most important force among the forces by virtue of which it can retain its position in space is undoubtedly the shearing resistance of the mass.
5. The force which tends to induce failure is __________
a) Shearing resistance
b) Force due to gravity
c) Force due to compression
d) Force due to loading
Answer: b
Clarification: Among the forces that tend to induce failure in a mass, the most important is the pull due to gravity which acts through the weight of the material.
6. When the forces tending to induce failure dominate over those tending to resist failure, the mass becomes stable.
a) True
b) False
Answer: b
Clarification: As, when and where the forces tending to induce failure dominate over those tending to resist failure, the mass becomes unstable.
7. The angle of slope up to which the materials are stable in a slope is called __________
a) Shear angle
b) Angle of failure
c) Critical angle
d) Sub-angle
Answer: c
Clarification: It has been observed that most materials are stable up to a certain angle of slope. This is called the critical angle of slope or also called as angle of repose and varies from 35° for unconsolidated sediments to 90° for perfectly crystalline unjointed rocks.
8. In the recent times what other aspect of the slope is considered for its stability?
a) The type of rocks in the slope
b) The type of land mass below the slope
c) Height of the slope
d) Length of the slope
Answer: c
Clarification: In fact much importance has been attached in recent times to the height of the slope in addition to the angle of slope for determining the factor of safety.
9. Solvent action can been seen in rocks which are made of _______ minerals.
a) Active
b) Inactive
c) Soluble
d) Insoluble
Answer: c
Clarification: The solvent action of water should also not be underestimated. In rocks like gypsum and limestone, or in those rocks which have soluble minerals as their constituents, water may gradually remove the soluble components reducing the shearing strength of the mass.