Draw a plan of a typical strip mine showing all operational features and equipment.
Answer the following:
a. Provide a sketch to show the difference between the final and the working slopes.
b. Why do operators try to steepen the final slope to an allowable safe maximum angle?
Define the following a. Swell factor
b. Struck Capacity
c. Heaped Capacity
d. Fill Factor
e. Bank cubic metre
f. Loose Cubic metre
g. Working slope
h. Final pit wall
i. Ramp
j. Windrow
Discuss the following:
a. Summarise the steps in the development of an open pit mine.
b. What are the purposes of safety benches?
c. What is the width of a safety bench?
d. Discuss some of the aspects that enter into bench height selection?
e. What is meant by the term push-back?
Answer the following
a. Define materials handling in surface mining
b. Name the different types of operations in materials handling
c. Name the different types of machine used in these operations
d. Name and discuss the major factors that determine the selection of excavation equipment. e. Define the idealised output of a power shovel
Answer the following:
a. Discuss the factors that are considered in the selection of a truck as a haulage unit.
b. In determining the cycle time of a haulage unit name the factors in relation to the haulage road that need to be considered
c. Define the following
i. Grade resistance
ii. Rolling resistance
iii. Total resistance
Define the following terms:
a. Availability
b. Operational availability
c. Mechanical availability
d. Physical availability
e. Utilization
f. Working efficiency
g. Job efficiency
Differentiate between the following:
a. Scheduled hours
b. Annual hours
c. Total hours
d. Working hours
e. Shift hours
f. Operating hours
What are the advantages of trolley assist for a truck haulage system?
Why is the mechanical availability always less than the operational availability? How does mechanical availability vary with the life of the machine?
Why is knowing the coefficient of traction important?
Answer the following:
i. In general, a road consists of several layers. Draw and label different layers and discuss their functionality.
ii. How is the load from the tyres distributed in the different layers of a road foundation? Discuss.
iii. Draw a typical stress envelope for dual rear wheel tyres for a truck.
Point out, on the drawing, the most affected area on the sub-grade.
Which of these would be considered an excessively steep a grade for a normal rear dump truck? a. 4% b. 6% c. 10% d. 12%
Draw and label in detail an excavator
What is the difference between a shovel and an excavator?
Sketch and label the four most common slope failure types?
Describe the various methods of truck loading using either a shovel or excavator fitted as a backhoe
What are the advantages and disadvantages of in-pit crushing
Continuous surface miners such as the Wirtgen surface miners are used at a number of operations worldwide. Describe such a machine and detail the type of operation where such a machine has advantages over traditional surface mining techniques.