Handbook on Quarrying

Compiled by A.H. Dutton

HANDBOOK No. 1 (Revised edition 1993)

DEPARTMENT OF MINES AND ENERGY SOUTH AUSTRALIA

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Stripping overburden at Wheal Hughes copper mine opencut, Moonta. (Photo 039485)

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Contents

CHAPTER l INTRODUCTION................................................................................................................11 Production of construction materials in South Australia .........................................12 Crushed rock aggregates ............................................................................12 Construction sand .......................................................................................15 Brick clay ...................................................................................................15 Dimension stone .........................................................................................16 Production of minerals in South Australia ...............................................................17 Middleback Ranges iron ore deposits ........................................................17 LeighCreekcoalfield .................................................................................20

CHAPTER 2 PRODUCT TESTING AND SPECIFICATIONS .............................................................21 Sampling ..................................................................................................................21 Testing ....................................................................................................................21 Specifications ...........................................................................................................25 Fine concrete aggregate .............................................................................26 Coarse concrete aggregate .........................................................................26 Road sealing aggregate ..............................................................................27 Crushed rock and quarry rubble .................................................................28

CHAPTER 3 ENVIRONMENTAL MANAGEMENT ............................................................................29 What is the environment? ........................................................................................30 Why protect the environment? ................................................................................30 Range of environmental impacts .............................................................................31 Impactidentification ................................................................................................32 Visual impact .............................................................................................32 Noise ..........................................................................................................36 Dust ............................................................................................................36 Dereliction of land .....................................................................................36 Associated activities ...................................................................................37 Pollution .....................................................................................................37 Rehabilitation ..........................................................................................................38 When to start ..............................................................................................39 Where to start .............................................................................................39 What to plant ..............................................................................................39 After-uses ...................................................................................................39 CHAPTER 4 GEOLOGY ....................................................................................................................44 Rocks and minerals..................................................................................................44 Classificationofrocks .............................................................................................44 Lithologicalclassification ..........................................................................44 Classificationbyage ..................................................................................46 Rock structures Folds .......................................................................................................... 48 Faults ..........................................................................................................53

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Bedding ......................................................................................................54 Cleavage and schistosity ............................................................................54 Joints ..........................................................................................................55 Strike and dip ............................................................................................57 Weathering and Erosion ..........................................................................................58 Application of geology ............................................................................................58

CHAPTERS 5 DRILLS AND DRILLING ..................................................................................................60 Hammer drilling ......................................................................................................60 Surface hammers ........................................................................................60 Down-hole hammers ..................................................................................63 Machine mounting .....................................................................................69 Surface versus down-hole hammers ..........................................................71 Rotary drilling .........................................................................................................72 Auger drills ................................................................................................72 Reverse circulation drills ...........................................................................72 Rotary drills ...............................................................................................75 Circulatoryfluids .......................................................................................75 Operational features ...................................................................................76 Diamond drilling .....................................................................................................78 Choice of drill ..........................................................................................................79 Compressors ............................................................................................................80 Types of compressor ..................................................................................80 General requirements for air reticulation ...................................................82

CHAPTER 6 EXPLORATION ..................................................................................................................83 Stage1Officestudies ..............................................................................................83 Stage 2 Field reconnaissance and site selection ......................................................84 Stage 3 Preliminary site investigation .....................................................................85 Stage 4 Detailed site investigation ..........................................................................86 Stage 5 Preparing a development plan ....................................................................90

CHAPTER 7 EXPLOSIVES ....................................................................................................................91 Velocity of detonation (VOD) .................................................................................91 Types of explosives used in quarrying ....................................................................92 ‘Low’ explosives ........................................................................................92 ‘High’ explosives .......................................................................................92 Detonating (initiating) explosives ..............................................................93 Primers and boosters ..................................................................................93 Ammonium nitrate (AN) mixtures .............................................................93 Properties of explosives ...........................................................................................98 Sensitivity ..................................................................................................98 Relative weight strength ............................................................................98 Relative bulk strength ................................................................................99 Water resistance .........................................................................................99 Fumes .........................................................................................................99

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Detonating explosives ...........................................................................................100 Plain detonators (used with safety fuse) ..................................................100 Instantaneous electric detonators .............................................................100 Delay electric detonators ..........................................................................100 Signal tube detonators ..............................................................................103 Detonating cord ........................................................................................103 Initiation of explosive charges ...............................................................................105 NON-ELECTRIC INITIATION ..........................................................105 Safety fuse initiation ................................................................................105 Signal tube initiation ................................................................................106 Detonating cord initiation ........................................................................107 ELECTRICAL INITIATION ...............................................................109 Blasting circuit tester ...............................................................................111 Exploders .................................................................................................111 Firing from power mains .........................................................................113 Firing from batteries ................................................................................113 Electric circuits ........................................................................................113 Testing circuits .........................................................................................115 Hazardswithelectricfiring ......................................................................116 Explosives Regulations .........................................................................................118 Magazines ................................................................................................119 Transport ..................................................................................................121 Destruction of defective explosives.......................................................................119 Nitroglycerine compounds .......................................................................119 Watergel and emulsion explosives ...........................................................120 ANFO mixture .........................................................................................121 Detonating cord ........................................................................................121 Detonators ................................................................................................121

CHAPTERS 8 GROUND VIBRATION AND AIR OVERPRESSURE .................................................122 Ground vibration ...................................................................................................123 Vibration terminology ...........................................................................................123 Measuring ground vibration .....................................................................123 Damage ....................................................................................................125 Human response .......................................................................................126 Australian Standard ..................................................................................127 Controlling ground vibration ...................................................................129 Predicting ground vibration .....................................................................130 Air overpressure ....................................................................................................130 Measuring air overpressure ...................................................................................131 Damage ....................................................................................................131 Human response .......................................................................................133 Standards ..................................................................................................133 Proposed Australian Standard ..................................................................133 Controlling air overpressure ....................................................................133 Predicting air overpressure ......................................................................135 Service to industry .................................................................................................135

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CHAPTER 9 QUARRY BLASTING .......................................................................................................138 General considerations ..........................................................................................138 Purpose of blasting ...................................................................................138 Physical characteristics of rocks ..............................................................139 Amenity considerations ...........................................................................139 Primary blasting ....................................................................................................139 Blasting theory .........................................................................................139 Burden ......................................................................................................139 Spacing .....................................................................................................143 Fragmentation ..........................................................................................144 Selection of burden, spacing and hole diameter ......................................145 Trial blasts ................................................................................................146 Profilingblastholes..................................................................................148 Blasting in single holes ............................................................................149 Blasting in rows .......................................................................................149 Choice of explosive ..................................................................................150 Quantity ....................................................................................................150 Angle drilling ...........................................................................................153 Smooth blasting and pre-splitting ............................................................154 Tunnel (‘Coyote’) blasting .......................................................................155 ‘Bulling’ or ‘chambering’ holes ...............................................................156 Quarrying using small diameter holes .....................................................156 Quarrying using large diameter holes ......................................................156 Secondary breaking ...............................................................................................157 Popping ....................................................................................................157 Plastering (‘Mud-capping’ or ‘blistering’) ...............................................157 Drop ball ..................................................................................................158 Rock breakers ...........................................................................................158 Other methods ..........................................................................................160 Summary ...............................................................................................................160

CHAPTER l0 LOADING AND TRANSPORT........................................................................................168 Integrated loading and hauling systems ................................................................168 Dozers ......................................................................................................168 Scrapers (‘Bowl scrapers’ or ‘Wheeled scrapers’) ...................................169 Draglines ..................................................................................................170 Loading systems ....................................................................................................172 Rope shovels (‘Power shovels’ and ‘Face shovels’) .............................................172 Hydraulic excavator .................................................................................174 Front-end loaders .....................................................................................176 Bucketwheel excavators ...........................................................................177 Bucket chain excavators ..........................................................................178 Cranes ......................................................................................................180 Transport systems ..................................................................................................180 Trucks .......................................................................................................181 Belt conveyors .........................................................................................185 Ancillary equipment ..............................................................................................181 Graders .....................................................................................................181

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Water carts................................................................................................182 Lighting plants .........................................................................................182

CHAPTER 11 QUARRYING METHODS ...............................................................................................183 Stripping ................................................................................................................183 Ripping .....................................................................................................184 Moderate scale stripping ..........................................................................185 Large scale stripping ...............................................................................187 Quarries or open pits .............................................................................................188 Hillside .....................................................................................................188 Single bench .............................................................................................190 Multibench ...............................................................................................190 Strip mining .............................................................................................193 Dimension stone .......................................................................................198 Soft rock ...................................................................................................198 Sand and gravel ........................................................................................200 Salt ...........................................................................................................200

CHAPTER 12 QUARRY UNIT OPERATIONS ......................................................................................201 Sequence of quarrying operations .........................................................................201 Drilling .....................................................................................................201 Blasting ....................................................................................................203 Loading ....................................................................................................203 Transport ..................................................................................................205 Roads........................................................................................................205 Reclamation .............................................................................................206 Dumps and slime dams ..........................................................................................206 Dumps ......................................................................................................210 Slime dams ...............................................................................................208 Pumping and drainage ...........................................................................................211 Surface runoff ........................................................................................................211 Groundwater ............................................................................................211 Removal of inpit water .............................................................................212

CHAPTER 13 OPERATIONAL PLANNING ..........................................................................................213 General ..................................................................................................................213 Quarry layout and amenity ....................................................................................214 Rate of production .................................................................................................215 Stripping overburden .............................................................................................216 Quarry benches ......................................................................................................216 Pit slope .................................................................................................................217

CHAPTER 14 HANDLING PLANT ........................................................................................................ 222 Belt conveyors .......................................................................................................222 Width and speed of belts ..........................................................................225

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Lump size .................................................................................................225 Belt speed ................................................................................................226 Determining belt capacity ........................................................................226 Power ......................................................................................................227 Loading and unloading ............................................................................229 Cleaning conveyor belts ...........................................................................231 Specialbeltconfigurations .......................................................................232 Safety .......................................................................................................232 Bucket elevators ....................................................................................................233 Stockpiles and bins ................................................................................................233 Stockpiles ..............................................................................................................233 Bins ..........................................................................................................237 Pumps ..................................................................................................................237

CHAPTER 15 CRUSHING AND SCREENING ......................................................................................238 Definitionsincrushingpractice .............................................................................238 Crushing ................................................................................................................239 Classificationofcrushers .........................................................................239 Jaw crushers .............................................................................................240 Gyratory crushers .....................................................................................242 Cone crushers ...........................................................................................243 Single roll crushers ..................................................................................243 Twin and triple roll crushers ....................................................................244 Hammer mills ...........................................................................................244 Impactors ..................................................................................................247 Vertical shaft impactors ............................................................................247 Other crushers ..........................................................................................248 Selection of crushers..............................................................................................248 Planning factors .......................................................................................248 Reduction ratio .........................................................................................249 Primary crushers ......................................................................................250 Comparison of gyratory and jaw crushers ...............................................251 Secondary and reduction crushers ...........................................................252 Feeders ..................................................................................................................252 Screening ..................................................................................................253 Grizzlies ...................................................................................................254 Screens .....................................................................................................254 Selection of vibrating screens ..................................................................254 Installation and operation ......................................................................................261 Installation ................................................................................................261 Operating instructions ..............................................................................261 Operation and servicing ...........................................................................261 Matching the crusher to the quarry plant .................................................262 Dust control ..............................................................................................263 Washing ....................................................................................................263 Organisation of crushing and screening ................................................................263 Supply of quarry rock ..............................................................................263 Flow through the plant .............................................................................263 Removal of product ..................................................................................264 Examples of practice .............................................................................................264

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CHAPTER16 WORKSHOPS AND STORES .........................................................................................271 General considerations ..........................................................................................271 Preventive maintenance .........................................................................................272 Facilities ................................................................................................................273 Storage of dangerous substances ...........................................................................273

CHAPTER 17 OCCUPATIONAL HEALTH AND SAFETY .................................................................274 Safety ..................................................................................................................274 Accident recording ...................................................................................274 Legislative requirements ..........................................................................275 Induction of new employees ....................................................................275 Maintaining safety awareness ..................................................................276 Machinery ................................................................................................276 Fire extinguishers .....................................................................................277 Electrical ..................................................................................................278 General .....................................................................................................278 First aid ....................................................................................................279 Injuries not related to accidents ...............................................................279 Noise ..................................................................................................................281 Effects of noise.........................................................................................281 How to deal with noise ............................................................................282 Types of noise ..........................................................................................283 Reducing noise exposure .........................................................................283 Nuisance aspect of noise ..........................................................................284 Remedies ..................................................................................................285 Dust ..................................................................................................................285 Health hazards ..........................................................................................285 Dust measurement ....................................................................................288 Remedial measures ..................................................................................289

CHAPTER 18 ADMINISTRATION, MANAGEMENT AND FINANCE .............................................291 Company structure and procedures .......................................................................291 Quarry accountancy ...............................................................................................294 Quarry costs ...........................................................................................................294 Administration .......................................................................................................295 Labour ......................................................................................................295 Stores........................................................................................................296 Plant and equipment .................................................................................296 Management ..........................................................................................................296 Training .................................................................................................................297 Innovations ............................................................................................................297 Project evaluation ..................................................................................................298

CHAPTER 19 DEPARTMENT OF MINES AND ENERGY..................................................................299 Services available to the public .............................................................................299

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ACKNOWLEDGEMENTS ..............................................................................................302

SELECTED BIBLIOGRAPHY ........................................................................................302

GLOSSARY ..................................................................................................................304