Spatial positioning of sidewall stations in a narrow tunnel environment: a safe alternative to traditional mine survey practice

Appendix 13.

A solver equation of the observed angles and distances to determine a provisional co-ordinate

Appendix 14.

A least squares adjustment of a freestation point.

Index

“working at heights, 54

Alignment, 3, 375

Benchmark, 45

braced quadrilaterals, 130

centering, 73, 120

check survey, 5, 29, 78, 110, 111, 131, 143, 144, 146, 152, 153, 163, 227, 234, 240, 241, 251, 262, 263, 264, 266, 272, 278, 281, 284, 310, 328, 330, 333, 334, 335, 380, 384, 390, 391, 398, XLII, XLIII, LII, LV

Class, 30, 31, 36, 38, 39, 44, 45

closed traverse, 93, 153, 164, 165, 170

double zig-zag, 130

Electronic Distance Measuring, 84

error propagation, 101, 109

factors, 7, 60, 74, 75, 124

freestation, 88, 100, 101

geometry, 12, 14, 18, 33, 91, 98, 104, 105, 122, 174, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 218, 219, 221, 222, 251, 254, 255, 257, 259, 260, 261, 266, 273, 274, 284, 289, 308, 311, 314, 316, 317, 319, 378, 392, 396, XLII, XLV

Geometry of observations, 91, 104

Gretley Coal Mine Disaster, 24

ground conditions, 74

gyroscope, 15, 94, 131, 146, 162, 163, 237, 251, 264, 265, 279, 282, 287, 309, 332, 333, 335, 385, 390, XLIII, LIV

hot-spark, 58

limits of error, 3, 4, 8, 11, 12, 14, 27, 28, 29, 30, 33, 34, 40, 41, 45, 46, 47, 48, 49, 60, 77, 84, 91, 92, 138, 163, 170, 174, 182, 187, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 378

MHSA, 12, 25, 29, 36, 40, 46, 47, 48, 49, 80, 110, 138, 143, 145, 153, 163, 164, 165, 170, 172, 174, 215, 222, 227, 235, 240, 245, 251, 258, 264, 267, 278, 280, 284, 290, 293, 328, 330, 333, 336, 374, 376, 377, 378, 379, 380, 383, 385, 389, 390, 392, 393, 396,LIII

Mine Health and Safety Act, 22, 33, 48, 50, 59, 79, 152, 189, 223, 236, 245, 280, 281, 374, 379, 385, 389

Mine surveying, , 2, 375

minimum standard of accuracy, 29, 152, 153, 220, 235, 236, 240, 263, 264, 265, 278, 281, 379, 383, 390

Positional Uncertainty, 38

Primary Survey, 30

primary survey network, 10, 12, 14, 15, 30, 122

redundant measurement, 106

refraction, 15, 19, 60, 62, 63, 66, 68, 81, 120, 121, 123, 127, 130, 184, 249

resection, 9, 33, 41, 87, 91, 95, 97, 98, 99, 100, 102, 103, 105, 108, 109, 116, 117, 118, 122, 129, 136, 172, 179, 181, 183, 186, 215, 233, 234, 242, 243, 273, 274, 276, 278, 281, 283, 289, 293, 303, 310, 312, 318, 319, 321, 324, 327, 330, 374, 379, 384, 391, 394,396, XXXV, XLI, XLII, XLIII, XLVIII, XLIX, LIII

Resection, 9, 97

Safety, , 3, 5, 7, 10, 11, 12, 15, 18, 27, 28, 29, 32, 42, 43, 52, 53, 54, 78, 91, 374

sidewall station, 11, 14, 15, 136, 174, 177, 179, 180, 181, 186, 193, 216, 221, 223, 229, 237, 238, 240, 244, 245, 247, 248, 249, 250, 253, 254, 255, 259, 266, 267, 269, 273, 294, 295, 296, 306, 332, 377, 379, 380, 381, 382, 383, 384, 385, 389, 393, XXIX, XL, XLI, XLIV, LIV

sidewall stations, 14, 128, 136, 172, 173, 175, 176, 177, 178, 180, 181, 183, 184, 187, 190, 191, 192, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 219, 222, 227, 229, 231, 232, 233, 234, 238, 247, 249, 252, 253, 254, 273, 283, 297, 304, 306, 307, 309, 313, 319, 321, 328, 330, 335, 382, 393, 398, 399, XL, XLI, XLII, XLIII, XLIV

Siloam tunnel, 2

Standards, 19, 50, 53, 56, 58

survey station, 262

traverse, 14, 29, 32, 34, 36, 40, 42, 45, 63, 89, 92, 93, 109, 110, 111, 119, 120, 126, 130, 138, 140, 143, 144, 145, 146, 152, 153, 163, 165, 166, 167, 170, 182, 220, 231, 235, 250, 282, 334, 393, 396

Closed, 12, 93

Open, 90, 93, 94

Traversing, 92

Triangulateration, 102

triangulation, 34, 36, 87, 91, 95, 96, 102, 105, 113, 129, 276, 290, 327

Triangulation, 34, 45, 87, 91, 95

Trilateration, 96

Tunnel of Eupalinos, 2

ventilation, 13, 61, 70, 72, 104, XLIV

Visibility., 70

Wall station s, 116

wall station surveying, 106, 286, 291

Wall Stations, 116

working at heights, 16, 19, 52, 53, 54, 56, 59, 73, 80, 81, 171, 232, 245, 249, 283, 386, 387, 388

Working at heights, 7, 9, 51

zig-zag method, 120, 121

1^ An event where an excavation breaks into another excavation, in some text this is referred to as a “breakthrough”.

2^ The required inclination of a development end.

3^ An event where a mining excavation breaks into another excavation or area where an accumulation of water or gas may occur.

4^ Refers to the Standards of Accuracy defined by a standard procedure or regulation such as that defined by the MHSA. Also referred to as the “minimum standards of accuracy”

5^ A tunnel being for the purpose of providing access to the orebody of a mine.

6^ A survey made to verify the accuracy of the original survey and the strengthening of the quality of a survey network.

7^ The roof of an underground excavation. In some texts this is referred to as the “back” of the excavation

8^ a survey station installed in the sidewall of an excavation in a similar manner as that of a grade-peg , but with the co-ordinates of the survey station accurately surveyed.

9^ A collapse of rock from the roof or sidewall of an excavation, normally gravity induced

10^ A continuous pillars left in situ on the inside of every mine boundary, the width of which, measured horizontally and at right angles to the boundary line, must not be less than 15(fifteen) metres for underground coal mines and for all other mines a pillar of 9 (nine) metres. [1]

11^ A base between two or more survey stations between which the distance and direction has been accurately determined and verified. The baseline is used as the point of origin for any survey.

12^ Electronic Distance Measuring device

13^ Directorate of Mineral Resources, previously known as the Department of Minerals and Energy

14^ Personal Protective Equipment

15^ The floor of an underground excavation

16^ Lifting equipment includes ladders, platforms, scaffolding and mobile lifting equipment

17^ FOG accidents refers to incidents where rocks fall from the roof or sidewall of an excavation.

18^ Freestation is an application that, similar to that of a resection, uses a combination of distances and angles observed to known points to determine the position of an instrument setup at an unknown position

19^ Application is a subroutine in the instrument software of the instrument designed to perform specific surveying procedures such as setting out or performing a traverse in a clearly defined structure

20^ Computer Aided Drawing software

21^ The hangingwall or roof of an excavation

22^ A weight normally constructed from brass suspended from a braided nylon string of approximately 1mmilimeter in diameter. The plum bob is generally referred to as a machine bob in the South African mining context and is equipped with a spring loaded pin to ensure the accuracy of alignment of the instrument.

23^ A known reference point used for orientation purposes.

24^A new survey station that is in the process of being surveyed.

25^ A spad is flat, tapered brass nail with a small hole in the flat portion of the head to facilitate the insertion of a thin string attached to a plumb bob or a hooked survey target in the spad.

26^ An instrument with no electronic measuring capability, making use of lenses to take readings directly to the horizontal and vertical circles, normally with the aid of a micrometer reading

27^ Development end is defined as a tunnel mined for the purpose of providing access to the orebody

28^ a group of four pegs installed in the sidewall of an excavation, normally installed perpendicular to the direction of development, used to provide visual control to the miner to maintain the footwall a pre-determined distance below the gradient indicated by the grade pegs

29^ A ribbed plastic plug used for the attachment of bolts to walls.

30^ This would normally be a plastic shirt button of approximately 7 to 10 millimeters in diameter

31^ A method using two targets or buttons to effectively double the amount of forward observations to a new point.

32^ A braided nylon string of approximately 1mm in diameter.

33^ In the case where the instrument vertical circle is orientated to read zero when pointing vertically up

34^ the gradient of a tunnel is defined by the height of the footwall of the excavation to a pre-determined gradient expressed as a ratio e.g. 1:200 or as a percentage e.g. 8%.

35^ A cross-cut is a tunnel that is broken away from the main haulage for the purpose of mining towards the reef horizon in order to gain access to the reef for stoping purposes.

36^ A development sheet is a survey plan that shows a portion of the tunnels developed on a specific level of a mine

37^ Face left and Face right readings are a method by which the surveyor will observe a reference point and book the horizontal and vertical readings before plunging the instrument’s telescope and re-orientating the instrument on the same point before repeating the observations. This method has its origins in older survey equipment where reading on different parts of the circle ensured greater accuracy in the observations.

38^ Gijima GMSI “minemarkup” software

39^ A shaft developed at a gradient of between 8 and 12 degrees for the purpose of accessing the lower workings of the mine.

40^ A point of which the co-ordinates are fixed in three dimensions (y,x and z). Also referred to as a survey station or survey peg.

41^ The term “face” in surveying describes the practice of taking observations in “Face 1” of the instrument, normally with the set screws of the instrument on the right hand side of the instrument. When the instrument telescope is rotated through 180 degrees the instrument must also be rotated through 180 degrees in order to take the next reading. In this face, “face 2” the set screws of the instrument will be on the right-hand side of the instrument. This practice is to reduce the possibility of instrument and observer error. With modern instruments it is normal that the instrument will have a screen on both sides of the instrument, making the definition of face 1 and face 2 more complicated.

42^ Pickup is a term describing the process of measuring the dimensions of an excavation in relation to the survey network in the area for the purpose of representing the excavation on a mine plan. In the south African context this process if often referred to as “offsetting”

43^ A number of points, more than two, preferably four, installed in pairs. These points are generally known as survey stations and are installed on the gradeline of the excavation, perpendicular to the direction of mining. A second pair of points are spaced a minimum of three (3) metres away from the first set of points, on the gradeline and perpendicular to the direction of mining.

44^ A form of concrete support sprayed on the sidewall of an excavation

45^ The gradient of an excavation is determined by the use of the excavation and the method of transportation used, such gradients can be as little as 1:500 for track-bound transportation and limited to 8 to 10 degrees inclination for the efficient use of trackless equipment. Errors in gradient can lead to drainage problems and excessive wear to equipment as well as being an underlying cause for tramming accidents such as derailments of track-bound equipment.

46^ A method of placing reference points and markers that will guide the construction of new structures such as roads or buildings

47^ The Required gradient of the tunnel is the Major dip D°

48^ The absolute value of the deflection angle x° between the direction of the Major dip and the grade pegs where x° = │α° - H_o°│

49^ A tie is a form of tape surveying where an arc is measured between a fixed point and a new point. By scribing two or more arcs the intersection of these arcs will indicate the position of the point to be fixed.

50^ The term “markup instruction” in South African terminology would be a “survey letter” or “layout” and will be a legal document indicating the current face position and relevant information around the end.

51^ a term used to describe the process of marking off the blasting pattern of a tunnel in relation to the mine design direction and gradient for a development end for the purpose of blasting. This is normally referred to as “taking lines” in the South African context.

52^ Brackets with targets with a hole are used to ensure that the beam passes through the exact point, failure of the beam to pass through would indicate a disturbance in the positioning of the laser or targets.

53^ Barring is the process of using a pinch-bar to dislodge any loose rock from the hangingwall and sidewall of an excavation.