Highway Engineering Multiple Choice Questions on ” Sub Surface Drainage”.
1. In slab culverts RCC slab is placed over abudment of __________
a) Masonry
b) Pre stressed
c) Steel
d) Composite
Answer: a
Clarification: Generally the RCC slab is placed over abudment made of masonry only because other materials are costly.
2. The span of RCC slab is limited to __________
a) 1 m
b) 1.5 m
c) 2.0 m
d) 3.0 m
Answer: d
Clarification: The span of the RCC slab is usually limited to 3 m as it may have maintenance problems.
3. What is the minimum diameter used in pipe culverts?
a) 25 cm
b) 35 cm
c) 45 cm
d) 75 cm
Answer: d
Clarification: The minimum diameter of the pipe culverts used is 75 cm made of steel or RCC, usually RCC is only used as steel corrodes.
4. The GWT should be at a distance of _______ from ground level.
a) 0.5 m
b) 0.6 m
c) 1.2 m
d) 5.0 m
Answer: c
Clarification: The preferred distance from the ground level is 1.2m, however it is not a problem where ground water table is very low.
5. The total interruption to traffic in a year should not exceed __________
a) 45 days
b) 40 days
c) 30 days
d) 15 days
Answer: d
Clarification: The interruption should be kept as low as possible if unavoidable then we must provide it for 15 days.
6. The clay seal may be provided if the seepage zone is at a depth of less than __________
a) 1.2 m
b) 1.0 m
c) 0.9 m
d) 0.6m to 0.9 m
Answer: d
Clarification: The clay seal may be construed if the seepage zone is at a depth of less than 0.6 m to 0.9 m.
7. The capillary control can be controlled by how many methods?
a) One
b) Two
c) Three
d) Four
Answer: b
Clarification: The capillary control can be controlled by two methods called granular capillary cut off and impermeable capillary cut off.
8. To fulfill the adequate permeability the D15 of filter/D15 of foundation ratio should be greater than __________
a) 5
b) 10
c) 15
d) 20
Answer: a
Clarification: For adequate permeability, the ratio of the D15 of filter/D15 of foundation should be greater than 5.
9. The D85 point size is given by __________
a) Dp
b) 2Dp
c) 3Dp
d) 4Dp
Answer: b
Clarification: The D85 point size of the filter is given by the value 2Dp.
10. The loss of water from leaves present on embankment is called __________
a) Evaporation
b) Transpiration
c) Sublimation
d) Boiling
Answer: b
Clarification: The vegetation is provided on the embankment as they can absorb the water during heavy rain, and the loss is termed as transpiration.