ROCK FRAGMENTATION BY BLASTING

Transcription

1 First International Symposium on ROCK FRAGMENTATION BY BLASTING Lulea, Sweden, August 23-26,1983 UB/TIB Hannover Volume No. 3.

2 M ' i VOLUME No. 1-3 TABLE OF CONTENTS Page Volume Welcome to Lulea University of Technology. Vice Chancellor Dr Torbjb'rn Hedberg Opening of the Symposium and Introduction. Dr Per-Anders Persson, Chairman of the organizing committe KEY-NOTE SESSION Key-note. Fragmentation - a Review. Disintegration of solids Ulf Langefors, Sweden Gaps in the Field of Fragmentation by Blasting and some Thoughts about Future Research and Development. Agne Rustan, Sweden Blasting Experiments in the Luossavaara Research Mine Torbjorn Naartijarvi, Sweden Discussion Session 1. IMPORTANT PARAMETERS FOR ROCK FRAGMENTATION Chairman: CM. Lownds, vice chairman: Agne Rustan * A Study of Bench Blasting in Rhyoporphyry at a Reduced Scale and the Statistical Analysis of the Regularity for Fragmentation Distribution. Ma Bailing et al, China Production Drilling with high Accuracy. Lars Hermansson, Sweden Energy in Fragmentation. Per-Anders Persson, Sweden Discussion 1 Measurements and Predictions of Borehole Pressure Variations in Model Blasting Systems. F.O. Otuonye et al, USA The Effect of Charge Cavity Ratio on Rock Breaking. Zhu Rui-Geng et al, China The Influence of Controllable Blast Parameters on Fragmentation and Mining Costs. T.N. Hagan, Australia Discussion

3 Page Volume The Role of Stress Waves in Explosively Induced Bulk 53 1 Rock Motion. J.N. Edl, USA. Effect of Explosive Properties, Rock Type and Delays 71 1 on Fragmentation in Large Model Blasts. O.R. Bergmann, USA. On the Applicability of the Tensile Strength as an 79 Index to Rock Fragmentation. Kenneth Maki, Sweden Dynamic Photoelastic Studies on Delayed Pre-split Blasting. 97 K.R.Y. Simha et al, USA The Influence from Specific Charge, Geometric Scale 115 and Physical Properties of Homogenous Rock on Fragmentation. Agne Rustan et al, Sweden Regulations of the Process of Hard Rocks Fragmentation 143 by Blasting. K.A. Dolgov, USSR. Discussion Session 2. THEORY OF FRACTURING AND CRACK PROPAGATION Chairman: W.L. Fourney, vice chairman: Agne JRustan Spallation, Break-Up and Separation of Layers by Oblique Stress-Wave Interaction. H.P. Rossmanith et al, Austria Theoretical Research and Modelling of Directed Crack Propagation in Borehole Blasting. A.L. Isakov et al, USSR. Model Studies on Explosively Driven Cracks under Confining In-situ Stresses. K.R.Y. Simha et al, USA New Methods of Measuring Fracture Toughness on 199 -\ Rock Cores. F. Ouchterlony et al, Sweden Discussion Session 3. INSTRUMENTAL SYSTEMS FOR EVALUATION OF FRAGMENTATION Chairman: Dinis da Gama, vice chairman: Gunnar Almgren Rock Fragmentation by Explosives Stephen R. Winzer et al, USA

4 Page Volume The Development Concept of the Integrated Electronic Detonator. Paul N. Worsey et al, USA The Measuring Equipment and the Technique of Particle Velocity - at Investigation of Dynamic Rock Constitutive Equation In-situ. Wang Wu-Ling et al, China Interaction between Blast Design Variables; Experimental and Modelling Studies. J.J. Dawes et al, Australia Electromagnetic Velocity Gauge Measurement of Rock Mass-Motion during Blasting. Chapman Young et al, USA. Discussion Increasing Productivity through Field Control 301 and High-Speed Photography. R. Frank Chiappetta et al, USA A Method for Estimation of Fragment Size Distribution 333 with Automatic Image Processing. Olle Carlsson et al, Sweden Instrumented Model Scale Blasting in Concrete. 799 Gert Bjarnholt et al, Sweden Discussion 6 * 889 Session 4. FEM AND FINITE DIFFERENCE-CODES Chairman: Gwynn Harries, vice chairman: Per-Anders Persson Numerical Simulation of Fracture and Fragmentation. 347 L.G. Margolin et al, USA Simulation of Rock Blasting with the Shale Code. 361 T.F. Adams et al, USA Numerical Modelling of Rock Fragmentation. 375 S. Valliappan et al, Australia Computer Simulation of Blast Induced Vibration, Fracture 393 and Fragmentation processes in Brittle Rocks. Peter Digby et al, Sweden Computational Simulations of Dynamically induced 407 Fracture and Fragmentation. Stuart McHugh, USA Discussion 7 893

5 Session 5. MATHEMATICAL MODELS FOR BiAST AND FRAGMENTATION PREDICTIONS Chairman: L.G. Margolin, vice chairman: Roger Holmberg Page Volume Rock Displacement Velocity during a Bench Blast R.F. Favreau, Canada The modelling of Long Cylindrical Charges of Explosive Gwynn Harries, Australia The Kuz-Ram Model for Prediction of Fragmentation from Blasting. C.V.B. Cunningham, South Africa Discussion Computer Modelling of Fragmentation from an Array of Shotholes. CM. Lownds, South Africa Some Ideas on how to Improve Calculations of the Fragment Size Distribution in Bench Blasting. Hans Hjelmberg, Sweden. Session 6. INFLUENCE OF JOINT AND ROCK STRUCTURE ON FRAGMENTATION Chairman: Calvin J. Konya, vice chairman: Lennart Ottosson Differentiated Blasting Technique for Optimum Fragmentation at Aitik Copper Mine. A case study. Gustaf Tham, Sweden, Fragmentation in Jointed Rock Material W.L. Fourney et al, USA Influence of Joints on Rock Blasting. A Model Scale study. D.P. Singh et al, India Influence of Structural Geology on Controlled Blasting in Sedimentary Rocks - Case History. Goran Lande, USA Discussions Use of Comminution Theory to Predict Fragmentation of Jointed Rock Masses Subjected to Blasting. Dinis da Gama, Brazil The influence from Primary Structure on Fragmentation Yang Zu Guang et al, Sweden Experimental Investigation of Dynamic Surface Response to Explosive Loading. David C Holloway et al, USA Discussions

6 Session 7. COST ANALYSES OF THE SYSTEM OF DRILLING, BLASTING, MUCKING, CRUSHING AND TRANSPORTATION Chairman: Stephen R. Winzer, vice chairman: Ingemar Marklund Page Volume Electric Shovel Performance as a Measure of Blasting Efficiency. S.R. Williamson et al, Australia Development of a Fragmentation Monitoring System for Evaluating Open Stope Blast Performance at Mount Isa Mines. J.R.T. Grant et al, Australia Optimization of Open Pit Bench Blasting. Kai Nielsen, Norway The Precision of Long Hole Drilling with Modern Machines in Mining Operations. Angelo Medda et al, Italy Discussions Sublevel Stoping in Strassa Mine Kurt Gustafsson, Sweden Energy Requirements of Rock Breaking in Mining Operations; Considerations and Proposals. Pier Paolo Manca et al, Italy Accurate Bench Drilling Aids - for Better Overall Economy. Bjb'rn Karlsson, Sweden. Sources of Error in Long Hole Drilling their Consequences and how to avoid them. Per-Erik Lindvall, Sweden The Effect of Blasting on the Grade of Ore Crushing S.D. Victorov, USSR Discussions PANEL DISCUSSION Opening of the panel discussion. Roger Holmberg Part 1. The Organization of International Blasting Research and Standardization. Moderator: Agne Rustan Part 2. New Developments in Technique to Control Fragmentation and Their Impact on Modern Mining and Construction Engineering. Moderator: Roger Holmberg

7 Page Volume A New Technique for Controlled Small-Scale Hydraulic Fracturing. J.J. Kolle, USA Errata Sheet List of Participants 939 3