Marks distributions of Assignment 1: Q1-4, 3 marks each; Q5, 8 marks.

Briefly describe the technique of tunneling by drilling and blasting, including its applications, advantages and disadvantages (1A4 page word length 4 A4 pages).

Briefly describe the technique of mechanized tunneling, and use RBM or TBM as an example to describe its applications, advantages and disadvantages (1A4 page word length 4 A4 pages).

If the excavation diameter of the shaft is 6.0m, allowable time for mucking is 4.0hr per shift and the advance rate of shaft sinking is one round of 3.0m per shift, calculate the bucket size required for the mucking unit. (Hint: Swell factor)

A 6 m diameter TBM has been selected to undertake a tunneling operation. It is to operate at 4 rpm with a cutter head power of 750 kW in medium strength rock. Determine the predicted machine excavation rate using the monograph presented in the notes.

Calculate the direct unit cost of a 4.5 x 4.5 m drill and blast development in sandstone given the following:

Rock S.G 2.6

Labour cost $400/shift including on costs

Productivity 1.4m/shift

Rock bolts and mesh $25 per m2 supported

Depth drilled per round 3.6 m

Depth pulled per round 3.6 m

Overbreak 10%

Overall explosives cost average $2.40/kg

Materials cost excluding explosives and ground support $150/m

Jumbo drilling at $3.50/m drilled

Mucking and trimming $3.40/tonneDetail any other required assumptions.