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
a) silt
b) sand
c) clay
d) gravel
(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
a) Army method
b) Needle beam method
c) Austrian method
d) English method
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.
a) 2 m
b) 3 m
c) 4 m
d) 5 m
Ans: b
17. The most suitable soil for compressed air tunneling isa) silt
b) sand
c) clay
d) gravel
Ans: c
18. The needle beam method of tunnelling(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 tunnellinga) 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.
