TUNNEL ENGINEERING Multiple Choice Questions :-
1. Circular section of tunnels is not suitable for
a) carrying water
b) non-cohesive soils
c) tunnels driven by shield method
d) placement of concrete lining
Ans: d
2. What is the correct sequence of the following events of construction of a shaft in rock ?
1. drilling and blasting
2. timbering
3. pumping
4. mucking
Select the correct answer using the codes given below Codes :
a) 1,2,3,4
b) 1,4,2,3
c) 2,1,4,3
d) 2,4,1,3
Ans: b
3. A good blast with a good yield is obtained if the cut hole is
a) normal to face
b) inclined at 45° to the face
c) inclined at 15° to the face
d) inclined at 30° to the face
Ans: b
4. As compared to a single free face, if a charge of explosive is placed equidistant from two faces, then the yield
a) remains same
b) decreases
c) increases by 2.25 times
d) increases by 3.5 times
Ans: c
5. Which of the following are percussion drills ?
(i) shot drill
(ii) diamond drill
(iii) wagon drill
(iv) churn drill Of these statements
a) (i) and (ii) are correct
b) (iii) and (iv) are coiTect
c) (i) and (iv) are correct
d) (ii) and (iii) are correct
Ans: b
6. Drifters can be used to drill
a) only up holes
b) only down holes
c) horizontal or up holes
d) horizor„al, down or up holes
Ans: d
7. If ‘N’ is the number of shafts used, then the total number of feces available for attacking the excavation and construction in tunnels are
a) 2N
b) N + 2
c) 2 N + 1
d) 2 N + 2
Ans: d
8. The correct sequence of drilling equipment for increasing size of holes in tunnels is
a) wagon drill, churn drill, shot drill
b) wagon drill, shot drill, churn drill
c) shot drill, churn drill, wagon drill
d) churn drill, wagon drill, shot drill
Ans: a
9. Which of the following is not a component of the shield ?
a) propelling jacks
b) liner plate
c) hood
d) tail
Ans: b
10. In compressed air tunneling, the volume of free air provided is
a) 6 mJ per second per m2 of face area
b) 6 m3 per minute per m2 of face area
c) 20 m3 per minute per m2 of face area
d) 6 m3 per hour per m2 of face area
Ans: b
11. Assertion A : English method of tunneling requires more time as compared to other methods of tunneling.
Reason R : In English method of tunneling, the masons and excavators have to work alternately.
Select your answer based on the coding system given below :
a) Both A and R are true and R is the correct explanation of A.
b) Both A and R are true and R is not the correct explanation of A.
c) A is true but R is false.
d) A is false but R is true.
Ans: a
12. American method of tunneling
i) is suitable for large sized tunnels
ii) is no,’ suitable for railway or highway tunnel’s
iii) requires heavy timbers Of these statements
a) only (i) is correct
b) (i) and (iii) are correct
c) (ii) and (iii) are correct
d) (i) and (ii) are correct
Ans: a
13. Which of the following lining material is useful for shield driven tunnels in sub aqueous regions ?
a) stone masonry
b) timber
c) cast iron
d) cement concrete
Ans: c
14. If ‘D’ is the diameter of tunnel in metres, then the thickness of lining in mm, as per the empirical formula is given by
a) 42 D
b) 82 D
c) 104 D
d) 124 D
Ans: b
15. Which one of the following tunnelling methods is used for laying under ground sewers ?
a) Needle beam method
b) Army method
c) German method
d) Italian method
Ans: b
Tunnel Engineering Interview Questions
16. Ribs are used for strengthening and stiffening the liner plate for tunnels of diameter greater than
a) 2 m
b) 3 m
c) 4 m
d) 5 m
Ans: b
17. The most suitable soil for compressed air tunneling is
a) silt
b) sand
c) clay
d) gravel
Ans: c
18. The needle beam method of tunneling
(i) is suitable for soils in which roof can stand for few minutes without support
(ii) is suitable for brick lining
(iii) is suitable for concrete lining
(iv) requires large number of trench jacks Of these statements
a) only (i) is correct
b) (i), (ii) and (iv) are correct
c) (i), (iii) and (iv) are correct
d) (i) and (ii) are correct
Ans: b
19. Which of the following methods of tunneling is used for long tunnels at great depths ?
a) Army method
b) Needle beam method
c) Austrian method
d) English method
Ans: c
20. In Belgium method of tunnelling
a) construction of side walls is completed before invert and roof arch are built.
b) construction of roof arch is completed before side walls and invert are built.
c) construction of invert is completed before side walls and roof arch are built.
d) construction of invert and side walls is completed before roof arch is built.
Ans: b
21. What is the correct sequence of the following events in rock tunnelling?
1. marking tunnel profile
2. loading explosives and blasting
3. checking misfire
4. mucking
5. removing foul gas
6. setting up and drilling
7. guniting
Select the correct answer using the codes given below.
Codes:
a) 1,6,5,3,4,2,7
b) 1,2,6,3,5,4,7
c) 1, 6,2, 5,4, 3, 7
d) 1,6,2,5,3,4,7
Ans: d
22. Drift method of tunnelling is used to construct tunnels in
a) soft grounds
b) rock
c) self supporting grounds
d) broken grounds
Ans: b
23. Consider the following situations.
1. Soil is soft.
2. Volume of existing surface traffic on the alignment is heavy.
3. Track is at a deeper level.
4. Water table is high.
In the construction of Metro Railways, “Cut and Cover” method of construction is suitable in situations listed at
a) 1 and 2
b) 1 and 3
c) 1 and 4
d) 2 and 3
Ans: c
24. Which one of the following is considered to be an advantage of the heading and benching method of tunnel construction?
a) It is suitable for construction in unstable rocks.
b) In this method, it is easy to install timber support.
c) Tunnelling can be continuous and the work can be expedited.
d) In case of excessive water, it is easy to take correct steps.
Ans: c
25. In “full face” method of constructing tunnels, the first operation relates to
a) removal of bottom portion
b) excavation of one drift in the centre
c) removal of top portion
d) excavation being done along the periphery
Ans: d
26. Which one of the following is a component of a shield for tunnelling ?
a) liner plate
b) trench jack
c) stiffener
d) cutting edge
Ans: d
27. Assertion A : When rock conditions are favorable, it will not be necessary to take up concrete lining concurrently with the driving operations till the full length of the tunnel has been driven through rock.
Reason R : A tunnel through rock, hard or soft, does not need any concrete lining.
Select your answer based on the coding system given below:
a) Both A and R are true and R is the correct explanation of A.
b) Both A and R are true but R is not the correct explanation of A.
c) A is true but R is false.
d) A is false but R is true.
Ans: c