Question $1$

a$.$ What is a raise?

b$.$ What is the purpose of a raise?

$[5]$

c$.$ Briefly explain the methods of developing a raise

$[$S$]$

d$.$ What are the basic advantages of raise boring methods?

$[5]$

$[5]$

Question $2$

a$.$ Explain the common form of materials transport in open pit mining

$[5]$

b$.$ List the factors that influence the selection of load and haul equipment

$[5]$

c$.$ Given that the annual production of coal required in one mine is $60$ million $BCM.$ The mine is planning to operate two shovels of the same size to attain the required production. Select the bucket size for each shovel given the following information

Estimated Work Cycle $=122$ seconds

Operating days a year $=344$

Operating time$/$day $=22$ hrs

Swell factor $=1\mathrm{.}2$

Dipper$/$bucket Fill Factor $=0\mathrm{.}7$

availability and utilization $=0\mathrm{.}8$

Note: Average Bucket Payload $=$ Heaped Bucket Capacity $$ Bucket Fill Factor