Reference no: EM133135048

SVY2302 Mine Surveying - University of Southern Queensland

Underground Surveying Problems

Question 1: As Mine Surveyor of an underground mine you have been instructed to design a tunnel to join a crosscut to a haulage drive. The details of the crosscut and drive are shown below.

The face of the crosscut is 80m ahead of the last station. Both the crosscut and haulage drive are 5m wide and 4m high.

The tunnel is to have a circular horizontal alignment turning right from the crosscut with a radius of not more than 50m and not less that 30m with a maximum grade of 1 in 10.

a) Calculate the co-ordinates of the two tangent points for the most cost effective solution.
b) Plot the crosscut and drives at suitable scale showing all relevant information. Show the proposed walls as dashed lines on the plan.
c) Calculate the co-ordinates of a point (STN 45) that is 5m along the centreline of the tunnel from the TP in the crosscut (TP1). Check your calculations using the plan.
d) From this point (STN 45) a chord line bearing 82°43' is to be set out. At 2m intervals calculate the centreline offsets from this line and reduced levels of the floor.
e) At what chainage from STN 45 should mining cease and why?

Question 2:

To establish horizontal control on a new level the surveyor has traversed between two single wires hung in separate shafts.

The surveyor has set up the instrument at IS100 sighted to Wire X and has installed and made observations to wall stations WS150 and WS151. The observations at IS1000 are as follows.

The surveyor then sets up at IS101 observed to the wall stations as well as Wire
Y. The observations at IS101 are as follows.

a) Calculate the final adjusted co-ordinates for the two wall stations WS150 and WS151. Outline your steps clearly.

Question 3

The Falk underground coal mine has been mining the Hero seam which is a 4m high steaming coal, and the 3m high Devil seam, which is high grade soft coking coal, to allow blending and to produce coal for extra marketing potential.

It is proposed to join the present workings in the Hero seam with the workings in the Devil seam with a curved drive through the rock to allow vehicular access between the workings. The interburden is competent sandstone.

All survey stations are in the roof. The grades of both existing drives can be regarded as consistent.

Survey data is as follows:

The proposed drive will be 3m high and 5m wide, drivage to start at the floor at FH337. Mined material will be loaded out and dumped in back headings in the Hero workings.

The proposed drive will be a circular curve with a tangent at FH337 and tangential to centreline FD112 - FD113. Grade is to be consistent from FH337 to FD113.

a) Design the proposed drive. Calculate the radius and length of drivage.

b) Calculate where the drive meets the centreline FD112 - FD113 (the coordinate of TP).

c) Calculate the grade of the drive to meet the floor of the Devil seam at FD113.

d) Plot the drive plan showing all relevant information (show the proposed walls as dashed lines on the plan).

e) Calculate the total volume of material to be mined.