1. The diameter of coarse-grained soils having single grained structure is ____________
a) <0.002 mm
b) >0.002 mm
c) =0.002 mm
d) ≥0.002 mm
Explanation: Coarse-grained soil of diameter >0.002 mm settle out of suspension in water as individual grains independently of the grain.
2. The Coarse-grained soil settle in suspension due to ____________
a) Gravitational force
b) Surface force
c) Weight of the grain
d) All of the mentioned
Explanation: The weight of the grains in coarse-grained soil causes them to settle and get to particle-to-particle contact on deposition.
3. Which of the following force play an important role in honey comb structure?
a) Adhesion force
b) Gravitational force
c) Surface force
d) All of the mentioned
Explanation: The surface forces at the contact areas of the honey comb structure, prevent the grains from rolling down immediately in to positions of equilibrium among the grains already deposited.
4. The single grained structure is characteristic of fine-grained soils.
a) True
b) False
Explanation: The single grained structure is characteristic of coarse-grained soils. The honeycomb, flocculent and dispersed structures are found in fine-grained soils.
5. The behaviour of coarse-grained soils is not governed by ________
a) gravitational forces
b) mass energy
c) colloidal forces
d) interaction with pore fluid
Explanation: The particles of coarse-grained soils are sometimes called as bulky particles and these do not possess plasticity and cohesion. Their behaviour is primarily governed by gravitational forces and mass energy rather than colloidal forces.
6. The dispersed occurs in_______
a) sand
b) remoulded clay
c) gravel
d) silts
Explanation: Coarse-grained soils like gravel and sand form single grained structure. Fine sand and silts occur in honeycomb structure.
7. ________ structure is highly compressible and less permeable.
a) Flocculent
b) Dispersed
c) Honeycomb
d) Singe grained
Explanation: The dispersed structure has face-to-face contact in an approximately parallel manner having a lesser void ratio. Thus they have highly compressibility and less permeability. Whereas, the flocculent structures have low compressibility and high permeability.
8. Coarse grained skeleton is a structure of soil which is present in _________
a) fine grained
b) composite soil with large amount of coarse grained particles
c) composite soil with large amount of fine grained particle
d) coursed grained
Explanation: Coarse grained skeleton is a composite structure. Composite soil with a large amount of coarse grained particles form ‘coarse grained skeleton’. While composite soil with a large amount of fine grained particle form ‘clay matrix’.
9. Flocculated structure contains charged particles.
a) True
b) False
Explanation: The flocculated structure is present in clay particles with larger surface area. These are charged particles with positive charge on edges and negative charge on face.
10.Clay present in the marine area has ________
a) Flocculent structure
b) Dispersed structure
c) Honeycomb structure
d) Singe grained structure
Explanation: The salt present in the marine water acts as an electrolyte and thus reduces the repulsive forces between the particles which leads to the formation of the flocculated structure. The have high shear strength.