Q1: Consider the following statements with respect to tunnelling methods:
1. Full face excavation is suitable for small size tunnel of short length in compact rock. It is not suitable in urban areas.
2. Heading and Benching method is suitable for soft rock tunnelling of medium size.
3. Drift method is suitable for large tunnels in difficult or incompetent rock.
Which of the statements given above are correct ?

ANS:A - 1 and 3

1. The Full face method is suitable up to 3m and for the whole section, but not suitable for soft rock.

2. Heading and benching method suitable for hard rocks, drilling and mucking at the same time.

3. Suitable for large-size tunnels on hard rock, If the quality of the rock is bad or if it contains excessive water, this is detected in advance and corrective measures can then be taken in time. Small tunnel measuring 3 m x 3 m.