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

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

Hendrik Christoffel Ignatius Grobler

A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2015

Declaration page

I declare that this thesis is my own unaided work. It is being submitted to the Degree of Doctor of Philosophy to the University of the Witwatersrand, Johannesburg. It has not been submitted before for any degree or examination to any other University.

Signature of H.C.I. Grobler
24th^th day of April 2015

Abstract

This thesis proposes an alternative method of mine surveying in order to improve the safety and accuracy of primary survey network control in a narrow tunnel environment. It is argued that the traditional South African practice of establishing survey networks in the roof of a tunnel, although accurate, is time consuming and increases the risk exposure of survey crews. In the South African mining context Health and Safety legislation requires managers to take every precaution to ensure the health and safety of their employees. It is argued that current developments in survey technology can provide a safe and accurate alternative of establishing primary survey networks.

A method of establishing a primary network in the sidewall of a tunnel was tested under controlled conditions and evaluated under real working conditions. It was found that the accuracy of such a sidewall survey network can meet the defined accuracy requirements of the Mine Health and Safety Act, provided that specific geometric configurations are met and certain observation protocols are followed. A detailed risk analysis of the effect of external factors on the accuracy the network and the health and safety of workers was made. A standard practice was developed to mitigate the identified risks in the installation and maintenance of such a sidewall survey network. This thesis recommends that under specific conditions, a sidewall survey station network can provide first, a safe and accurate alternative to traditional mine survey networks and second, provide the required control for accurate setting-out surveys in a three-dimensional environment .

Acknowledgements

For Suretha and Alannah.

The author wishes to express his sincere appreciation to Professor Cawood for his support and assistance in the preparation of this manuscript. In addition, the author would like to extend his sincere gratitude to Ben van Staden, Angus Miller, Calvin Tijane, Wilson Kobe, Carel Roos, John McCaffery, Johan Bezuidenhout, Chanren Leung, David Wilson, Peter Knottenbelt, Donovan Anderson and Professor Antoine Bafabundi-Mulaba.

Table of Contents

Abstract 3

Table of Contents 5

List of figures 6

List of tables 7

Chapter 1Introduction 8

1.1.Mine surveying – an overview 8

1.2.The formulation of the fundamental question 13

1.3.The research outline 14

1.4.Overall objectives 14

1.5. Methodology 15

1.6. An overview of the literature search and further chapters 17

Chapter 2 Regulations, Standards and Codes of Practice 20

2.1.The South African Legislative Environment 20

2.1.1. Major contributors to injuries and Fatalities in the South African mining industry 22

2.2. Recent Mine safety incidents related to mine surveying 23

2.2.1. The Gretley Coal Mine Disaster 23

2.2.2.Beaconsfield Mine 25 April to 9 May 2006 24

2.2.3.The Chilean Mine Rescue 24

2.3.An Overview of relevant standards of accuracy. 25

2.3.1.The Mine Health and Safety Act; 1996 (Act 29 of 1996) 25

2.3.2 The Land Survey Act, 1997 (Act No 8. of 1997) 29

2.3.3 Federal Geodetic Control subcommittee (FGCS), Part 4, USA 31

2.3.4. Positional accuracies for primary control systems (ISO4463) 31

2.3.5. Intergovernmental Committee on Surveying and Mapping (ICSM SP1.7) 32

2.3.6.Canadian Survey Standards, General Instructions for Surveys, e-Edition, Appendix E4 – Accuracy standard for legal surveys 33

2.3.7.The Institute of Mine Surveyors of South Africa: Guidelines for standard Mine Surveying practice 34

2.3.8. Department of Industry and Resources, 2005, Mines survey - Code of practice: Safety and Health Division, Department of Industry and Resources, Western Australia 35

2.3.9.Survey and Drafting Directions for Mine Surveyors 2007 (New South Wales Coal) 36

2.3.10.Limits of error defined in the Tunnelling industry 37

2.4.A Comparison of Minimum standards of accuracy 38

2.5. Mining house corporate standards of accuracy 40

2.6. Other Corporate Safety Standards and Procedures 40

2.6.1.The Occupational Health and Safety Act of New South Wales 43

2.6.2. The BHP Divisional Standard Procedure 44

2.6.3. The Anglo American Fatal Risk Standards: Working-at-heights 45

2.7. Working at heights and the associated risks 45

2.8. The effect of external factors on the accuracy of a survey network 48

2.8.1. Illumination 49

2.8.2The effect of refraction 50

2.8.3. Visibility in the underground environment. 54

2.8.4. The interference of ventilation 56

2.8.5. The height of workings 56

2.8.6. Poor ground conditions 57

2.8.7. Moving Machinery 58

2.8.8. Production pressure 59

2.9. Summary of the findings in this chapter 61

Chapter 3Surveying Technology Review 63

3.1.Technological advances in Instrumentation 63

3.2.Electronic Distance Measuring technology 66

3.2.1 Electronic recording and data collection 67

3.2.2On-board and post-processing software 68

3.3.A review of traditional mine surveying methods 68

3.4.Conventional Surveying methods 70

3.4.1.Traversing 70

3.4.2.Intersection 72

3.4.3.Triangulation 72

3.4.4.Trilateration 73

3.4.5.Resection 74

3.4.6.“Vertical” Resections 75

3.4.7.Freestations 76

3.4.8.Three-dimensional two-point resection 77

3.4.9.Triangulateration 78

3.5. The geometry of observations 78

3.5.1. The effect of redundant measurements 79

3.5.2. The minimum number of observations 80

3.6.Error propagation 81

3.6.1.Sources in error in running a traverse 82

3.7.Alternative surveying techniques 83

3.7.1.The “Three Spad” Method 83

3.7.2.The “Random Transit” Method 84

3.7.3.Grade pegs in concrete Piers 85

3.7.4.Central European Survey methods 85

3.7.5.Wall Markers 86

3.7.6.Australian Wall Stations 86

3.7.7.The “Grade-peg” method 87

3.7.8.The JCI method of co-ordinated sidewall pegs 88

3.8. Tunnel surveying 88

3.8.1.The “Zigzag” method 89

3.9. Typical Tunnelling Network layouts 91

3.9.1. Diamond Light Source tunnel, Rutherford Appleton Laboratory, Oxfordshire 91

3.9.2.Euro “Channel” Tunnel 92

3.9.3.Fermilab Main Injector ring 92

3.9.4.Hong Kong tunnel Construction 93

3.9.5.Lane Cove Tunnel, Sydney, Australia 93

3.9.6.Japanese tunnel construction 94

3.9.7.Project Hallandsas, Sweden 94

3.9.9.Synchotron Radiation Source 95

3.9.10.Uetliberg tunnel, Zurich Western Bypass 95

3.10. Summary of the findings in this chapter 96

3.10.A comparison of survey methods using AHP 98

3.11.Proposed survey network to be established for the test phase 102

Chapter 4. Set up of the hangingwall control network 103

4.1.Introduction 103

4.2.Establishment of the control network 107

4.2.1.Check Survey 108

4.2.2.Bearing Check 109

4.2.3.Elevation check 110

4.2.4.Instrument used 110

4.2.5.Instrument Settings 110

4.2.6.Barometric pressure 111

4.2.7.Temperature 114

4.2.8.Final Settings 114

4.3.Required Standard of Accuracy 115

4.3.1.Interpretation of the MHSA Regulation 17(14) 115

4.4.The traditional hangingwall survey method 116

4.5.The closed traverse 118

4.5.1.Gyroscope Bearing Check 121

4.5.2.Calculation of the standard of accuracy for the closure at the breakthrough point 122

4.5.3. Possible sources of error in closure 125

4.5.4. Final co-ordinates for the hangingwall control network 126

4.6. Summary of the findings in this chapter 128

4.7.Introduction to Chapter 5 129

Chapter 5Establishment of the Sidewall station Network 130

5.1. Introduction 130

5.2. The establishment of the Sidewall survey station network 131

5.3. The co-ordinates of the Sidewall station network 133

5.4. Sidewall Survey station survey method accuracy evaluation 134

5.4.1.Description of the observation methodology 135

5.4.2.Description of the sidewall station Freestation calculation methodology 139

5.5. Sidewall station observations 142

5.6.Sidewall station data analysis 178

5.7. Closure obtained at the breakthrough point 181

5.8.Observations on the sidewall station survey method 181

5.9.Introduction to Chapter 6 182

Chapter 6. Three case studies involving sidewall station networks in the mining environment 183

6.1. Introduction 183

6.2. Rustenburg Platinum mines, Siphumelele 2 shaft 183

6.2.1.The establishment of the Sidewall survey station network 184

6.2.2.Description of the observation methodology 186

6.2.3.Method of evaluating the accuracy of the Sidewall Survey stations 190

6.2.4.Sidewall station network results 190

6.2.5.Closure obtained at the breakthrough point 191

6.2.6.The two-point freestation method 193

6.2.7.A Comparison between the two methods 197

6.2.8.Conclusion 199

6.2.9.Does the sidewall station method meet MHSA standards? 199

6.2.10.Is the sidewall station method a safer method of surveying? 200

6.2.11.Does the sidewall station method provide a faster method of surveying? 200

6.2.12.Issues encountered during the survey study: 201

6.2.13.Perceived advantages of the sidewall station method: 202

6.2.14.Perceived disadvantages of the sidewall station method: 203

6.2.15.Suggestions and recommendations for using the sidewall station method would include: 204

6.3. South Deep Mine, 50 Level study 206

6.3.1.The use of the Sidewall survey station network 207

6.3.2.Methods and Standard procedures employed 208

6.3.3.Closures obtained 209

6.3.4.Does this method meet the minimum standards of accuracy? 210

6.3.5.Is this method a safer method of surveying? 211

6.4. Palaborwa Mining Company, Copper mine 211

6.4.1.Methods and Standard procedures employed 212

6.4.2.Closures obtained 213

6.4.3.Does this method meet the minimum standards of accuracy? 221

6.4.4.Is this method a safer method of surveying? 222

6.4.5.Further advantages or disadvantages of the method? 222

6.5. Conclusion 222

Chapter 7. A critical analysis of current international practice: lessons towards developing South African standard mine survey procedures 223

7.1. An overview of international wall survey standard procedures 223

7.2. Phase 1. Preparation 224

7.2.1 Safety considerations 224

7.2.2. Equipment used 224

7.3. Phase 2. Installation 224

7.3.1Survey Station installation 225

7.3.2 Positioning of survey stations (wall stations) 225

7.3.3 Marking the point 225

7.3.4 Protecting the point 226

7.4. Phase 3. Observation protocol 226

7.4.1. Geometry of observations 226

7.4.2. Maximum and minimum angles and distances 226

7.4.3. Number of observations 227

7.4.Phase 4. Calculation methodology 228

7.5. Phase 5. Storage and presentation 228

7.5.1. Record keeping 228

7.5.2. Pickup instructions 229

7.6. Check surveys 229

7.6.1.Accuracy 230

7.6.2. Methods of check surveying 231

7.7.SWOT analysis of current international survey practice using wall station type surveying methods 232

7.7.1. Strengths 232

7.7.2.Weaknesses 233

7.7.3. Opportunities 235

7.7.4. Threats 236

7.8.Considerations for the development of a standard practice unique to South African mine surveying 237

7.9.Conclusion 238

Chapter 8. A proposed guideline for the establishment of a Sidewall Station Survey network 240

8.1. Introduction 240

8.1.1. Scope of this guideline 241

8.2. Change management 242

8.3. Proposed guidelines for the establishment and propagation of a sidewall station survey network 242

8.4. Phase 1. Preparation 243

8.4.1Safety considerations 243

8.4.2Planning of the network 245

8.4.3Equipment used 248

8.4.4Personnel requirements 249

8.5. Phase 2. Installation 251

8.5.1Survey Station installation 254

8.5.2Changing to a sidewall survey station network from a hangingwall network 255

8.5.3Changing to hangingwall network from a sidewall survey station network 255

8.5.4Positioning of sidewall survey stations 255

8.5.5Marking survey stations 256

8.5.6Protecting survey stations 256

8.6. Phase 3. Observation protocol 256

8.6.1Risk factors in observation 257

8.6.2Geometry of observations 260

8.6.3Maximum and Minimum angles and distances 261

8.6.4 Number of observations 263

8.6.5Field notes 267

8.7Phase 4. Calculation methodology 267

8.8. Phase 5. Storage and presentation 269

8.9. Phase 6. Check survey 271

8.9.1.Check survey baseline 271

8.9.2.Accuracy 272

8.9.3.Process of check survey adjustment 272

8.10.Conclusion 274

Chapter 9. Three dimensional mining control using sidewall stations, a solution. 275

9.1.The requirements for direction and gradient mark-up. 275

1.1.Direction lines and gradient control by conventional means. 275

1.2. Setting-out gradient using the minor dip method. 276

1.3. An application of the theorem for the intersection of two lines. 276

9.2.Site application of the intersecting lines method. 284

9.3.Evaluation of setting-out technologies and techniques 290

1.4.The gradient control method. 291

1.5.Direction control using marks made on the grade strings. 292

9.4. A review of current laser technology. 293

1.6. String suspended lasers. 293

1.7.In-line Suspended tunnel lasers. 295

1.8.Dual-beam laser devices. 296

1.9. Sleeve laser devices. 298

1.10.Long range mounted laser systems. 300

1.11.Applications for totalstation technology. 301

1.12.A perspective on developing technologies. 303

9.5. Interpretation based on the SWOT analysis. 303

1.13.How can the strengths of the method or technology be used to overcome the identified threats? 303

1.14. How can the strengths of the method/technology be used to take advantage of the opportunities? 304

1.15.How can the weaknesses be addressed to take advantage of the opportunities? 305

1.16.How can the weaknesses be minimized to take overcome the threats identified? 306

9.6.Conclusions and recommendations. 307

1.17.An estimation of the cost of technology as a percentage of development cost. 309

Chapter 10. Conclusion and Recommendations 311

10.1 Introduction. 312

10.2Evaluation of the precision of the sidewall survey station network 314

10.3Evaluation of the accuracy of the sidewall survey station network 316

10.4 Conclusion 317

10.5 Recommendations 320

10.5.1National Standard Operating Procedures for Mine Surveying 322

10.5.2Change management to introduce the sidewall station method of surveying 323

10.5.3The effect of the misalignment of the optical centre and the nodal point of a prism 324

10.5.4The calculation of quality control parameters in the establishment and maintenance of underground survey networks 324

10.5.5Confidence limit of minimum standards of accuracy and error ellipses 324

10.5.6Shaft surveying technique and monitoring of the position of shaft wires using the freestation method of surveying 325

10.5.7Measuring and profiling of underground excavations 325

10.5.8The effect of elastic rebound and tunnel deformation on the movement of sidewall reference points 326

10.5.9Underground location with transponders in sidewall stations 326

10.6Conclusion 327

Bibliography 328

Appendix 1. 344

Appendix 2. 345

Appendix 3. 346

Appendix 4. 348

Appendix 5. 350

Appendix 6. 352

Appendix 7. 353

Appendix 8. 354

Phase 1. Preparation 357

Phase 2. Installation 361

Phase 3. Observation protocol 367

Phase 4. Calculation methodology 371

Phase 5. Storage and presentation 371

Phase 6. Check survey 372

Appendix 9. 375

Appendix 10. 376

Appendix 11. 377

Appendix 12. 396

Appendix 13. 424

Appendix 14. 426

Index 429