250+ TOP MCQs on Design of Flexible Pavements – 1 and Answers

3. The flexible pavements consists of _____________
a) thin wearing surface
b) thick wearing surface
c) no wearing surface
d) wearing surface present at only specific places
Answer: a
Clarification: The flexible pavements consists of thin wearing surface which is built over a base and sub-base course, and they rest on compacted surface. The wearing surface is smooth in order for the vehicles to ride on it.

4. __________ can take appreciable tensile stress.
a) Flexible pavement
b) Semi-flexible pavement
c) Rigid pavement
d) Tar pavement
Answer: c
Clarification: A rigid pavement can take appreciable tensile stress and is capable of bridging small weakness and depression in the sub-grade. The flexible pavements are able to resist only small tensile stresses.

5. The flexible pavements resist ___________ tensile stresses.
a) only very small
b) large
c) negligible
d) very large
Answer: a
Clarification: The flexible pavements consists of thin wearing surface which is built over a base and sub-base course and are able to resist only small tensile stresses. The semi flexible pavement can possess appreciable flexural strength.

6. A semi-flexible pavement is made of ___________
a) tar only
b) bitumen only
c) dry-lean concrete
d) aggregates only
Answer: c
Clarification: A semi-flexible pavement is made of dry-lean concrete or soil cement. The semi-flexible pavement possesses qualities intermediate between the flexible and the rigid pavements.

7. The modulus of electricity of a semi-flexible pavement is ___________
a) lower than concrete
b) greater than concrete
c) equal to concrete
d) is always zero
Answer: a
Clarification: The semi flexible pavement possess appreciable flexural strength but its modulus of electricity is lower than concrete. This is due to the fact that the semi flexible pavement is made of dry-lean concrete or soil cement.

8. The design of flexible pavement is based on ________
a) slab mechanism
b) grain to grain transfer
c) column mechanism
d) footing mechanism
Answer: b
Clarification: The design of flexible pavement is based on the principle that the surface load is dissipated by carrying it deep into the ground through the successive layers of granular material. Thus it uses grain to grain transfer mechanism.

9. The flexible pavement do not distribute the load by ______
a) distributing through thick layers
b) grain to grain transfer
c) bending action
d) layered system
Answer: c
Clarification: The wheel load acting on the pavement will be distributed to a wider area such that stress decreases with the depth. The flexible pavement uses grain to grain transfer mechanism. Hence, it uses the concept of layered system.

10. The thickness design of flexible pavement is dependent on _________
a) uniformity of subgrade
b) thickness of subgrade
c) length of subgrade
d) strength of subgrade
Answer: d
Clarification: The thickness design of flexible pavement is influenced by the strength of subgrade as the load transfer is based on grain-to-grain mechanism. It also depends upon the quality and the compactness of the subgrade.

11. In the lower layers of the flexible pavement, lower quality materials are used.
a) True
b) False
Answer: a
Clarification: The flexible pavement distributes the load by grain-to-grain mechanism that involves many layers. As the load is distributed, it decreases in magnitude with the depth. Therefore, in the lower layers of the flexible pavement, lower quality materials are used.