Highway Engineering Multiple Choice Questions on “Stresses in Flexible Pavements”.
1. Boussinesq assumed soil as _____________
a) Homogeneous
b) Heterogeneous
c) Rigid
d) Flexible
Answer: a
Clarification: The assumption by Boussinesq was the soil is homogeneous, elastic and isotropic under a circular load.
2. Two elastic theory was developed by _____________
a) Boussinesq
b) Westergard
c) Burnister
d) McAdam
Answer: c
Clarification: The two elastic theory was developed by Burnister after Boussinesq developed the equation for evaluation of stress.
3. Boussinesq assumed the load as a _____________
a) Point load
b) UDL
c) UVL
d) Triangular load
Answer: a
Clarification: Boussinesq assumed the load as a single point load acting at a depth z and radius r.
4. The ratio of z/a=0 represent the stress at _____________
a) Top surface
b) Bottom surface
c) Middle
d) Maximum stress point
Answer: a
Clarification: The depth is zero, so the stress represented is at the surface of the pavement.
5. The z is a function of _____________
a) P, a
b) P, z
c) P, a, z
d) P only
Answer: c
Clarification: The depth is a function of the stress, depth and radius of the load acting on the point.
6. The ratio of the radius r/a=0 represents _____________
a) Center of chart
b) Center of load
c) Center of stress
d) Center of the pavement
Answer: a
Clarification: The radius is zero so it is possible only in a chart, which represents a point in the center of the chart.
7. The Poisson’s ratio of soil is assumed as _____________
a) 0.5
b) 0.6
c) 0.7
d) 0.8
Answer: a
Clarification: The Poisson’s ratio for a homogeneous soil is assumed as 0.5.
8. At surface the value of constant F is _____________
a) 1
b) 1.18
c) 1.5
d) 2
Answer: c
Clarification: The value of the constant F in finding out the deflection is 1.5.
9. The unit of deflection is measured in _____________
a) mm
b) N mm
c) joule
d) watt
Answer: a
Clarification: The deflection is measured in mm, cm or m depending on the requirement of the pavement.
10. The constant in rigid pavement design is _____________
a) 1.5
b) 1.18
c) 2
d) 3
Answer: b
Clarification: The constant value of the pavement in rigid pavement design is assumed as 1.18.
11. The diameter of the plate in plate load test is _____________
a) 30 cm
b) 30 mm
c) 3 m
d) 0.3 m
Answer: a
Clarification: The diameter of the plate used in the plate bearing test is 30 cm, it is a rigid plate.
12. What is the minimum deflection assumed in plate bearing test?
a) 0.25 mm
b) 0.25 cm
c) 2.5 cm
d) 2.5 m
Answer: b
Clarification: The deflection is usually fixed in plate bearing test and it varies between 0.25 cm and 0.5 cm.
13. The layer which should have high modulus of elasticity is?
a) Soil
b) Sub grade
c) Sub base
d) Pavement
Answer: d
Clarification: The modulus of elasticity should increase as the pavement layer increase from bottom to top.
14. What is the most superior material used in the pavement?
a) DBM
b) WBM
c) Tar
d) Bitumen
Answer: d
Clarification: The most superior material used in the pavement is bitumen which is mostly used for the surface layer.
15. In which layer system the modulus of elasticity will be equal for all layers?
a) Single
b) Double
c) Triple
d) Four layer
Answer: a
Clarification: In the single layer of system all the layers have same modulus of elasticity which means it is covered with only one material.