Rock Support and Reinforcement Practice in Mining

Rock Support and Reinforcement Practice in Mining
Author: A.G. Thompson
Publisher: Routledge
Total Pages: 800
Release: 2018-10-08
Genre: Technology & Engineering
ISBN: 1351418106

The text broadly covers recent developments in ground control techniques, and their at operating mines, worldwide. Specific topics include: design and analysis of support and re-inforcement in metalliferous mines, mesh, shotcrete and membrane support systems, and strata control in coal mines.

Ground Control in Mining

Ground Control in Mining
Author: S.K. Sarkar
Publisher: CRC Press
Total Pages: 189
Release: 2020-08-13
Genre: Technology & Engineering
ISBN: 1000099989

Covering the subject of ground control in mining, this volume looks at such topics as: rock-slab theory of ground pressure in work and practice, the role of in situ-stress in mine planning, and the status of the art of cable bolting.

Ground Engineering - Principles and Practices for Underground Coal Mining

Ground Engineering - Principles and Practices for Underground Coal Mining
Author: J.M. Galvin
Publisher: Springer
Total Pages: 693
Release: 2016-02-02
Genre: Science
ISBN: 3319250051

This book teaches readers ground engineering principles and related mining and risk management practices associated with underground coal mining. It establishes the basic elements of risk management and the fundamental principles of ground behaviour and then applies these to the essential building blocks of any underground coal mining system, comprising excavations, pillars, and interactions between workings. Readers will also learn about types of ground support and reinforcement systems and their operating mechanisms. These elements provide the platform whereby the principles can be applied to mining practice and risk management, directed primarily to bord and pillar mining, pillar extraction, longwall mining, sub-surface and surface subsidence, and operational hazards. The text concludes by presenting the framework of risk-based ground control management systems for achieving safe workplaces and efficient mining operations. In addition, a comprehensive reference list provides additional sources of information on the subject. Throughout, a large variety of examples show good and bad mining situations in order to demonstrate the application, or absence, of the established principles in practice. Written by an expert in underground coal mining and risk management, this book will help students and practitioners gain a deep understanding of the basic principles behind designing and conducting mining operations that are safe, efficient, and economically viable. Provides a comprehensive coverage of ground engineering principles within a risk management framework Features a large variety of examples that show good and poor mining situations in order to demonstrate the application of the established principles in practice Ideal for students and practitioners About the author Emeritus Professor Jim Galvin has a relatively unique combination of industrial, research and academic experience in the mining industry that spans specialist research and applied knowledge in ground engineering, mine management and risk management. His career encompasses directing ground engineering research groups in South Africa and Australia; practical mining experience, including active participation in the mines rescue service and responsibility for the design, operation, and management of large underground coal mines and for the consequences of loss of ground control as a mine manager; appointments as Professor and Head of the School of Mining Engineering at the University of New South Wales; and safety advisor to a number of Boards of Directors of organisations associated with mining. Awards Winner of the ACARP Excellence Research Award 2016. The Australian Coal Industry's Research Program selects recipients to receive ACARP Research and Industry Excellence Awards every two years. The recipients are selected on the recommendation of technical committees. They are honored for achievement of a considerable advance in an area of importance to the Australian coal mining industry. An important criterion is the likelihood of the results from the project being applied in mines. Winner of the Merv Harris Award from the Mine Managers Association of Australia. The Merv Harris Award is named for Merv Harris who donated money to be invested for a continuing award in 1988. With the award, the Mine Managers Association of Australia honors members of the Association who demonstrate technical achievement in the Australian Coal Mining Industry. The first award was granted in 1990, since then, only two people have received this honor. The book has received the following awards.... AGS (Australian Geomechanics Society) congratulates Dr Galvin for these awards

Rockbolting

Rockbolting
Author: Charlie Chunlin Li
Publisher: Butterworth-Heinemann
Total Pages: 286
Release: 2017-05-22
Genre: Technology & Engineering
ISBN: 0128499001

Rockbolting: Principles and Applications brings current theoretical and practical developments in the most widely used support device for underground rock excavations. Today, one cannot find any rock excavation project that does not use rockbolts for rock support. The worldwide annual assumption of rockbolts is in the billions, with pieces applied to mines, tunnels and other types of geotechnical projects for rock and soil reinforcement. The text is based on over 25 years of experience of the author both as academic and practitioner. The book introduces the principles and background concepts of rock support, and then offers a comprehensive overview of the mechanics of rockbolting, as well as current rock bolt types such as mechanical, grouted, self-drilling, grouted cables, frictional and yield rockbolts. Installation and performance assessment are covered next including load-displacement curves and energy-absorption capacities. Two chapters on design and quality control, respectively, cover failure mechanics, the selection process and the connections with other supporting devices. On quality control, the author explains the usual tests and displacement measurements. The final chapter brings current case studies that combine the concepts presented in the whole book. The book is a professional reference for engineers in the mining and geotechnical industries and can be used as research material for academics in rock mechanics and stability studies. Offers theoretical knowledge on rock bolts and rockbolting Covers the standard and most recent types of rockbolts Includes information on rockbolting in high stress rock Presents case studies that introduce practical applications in several conditions

Analyses for Design and Support of Coal Mine Intersections

Analyses for Design and Support of Coal Mine Intersections
Author: Sankhaneel Sinha
Publisher:
Total Pages: 366
Release: 2016
Genre: Coal mines and mining
ISBN:

Rock bolts have been extensively used as a support element in coal mines in the US for about 40 years. Longwall development and partial extraction room-and-pillar mining systems now rely heavily on fully-grouted roof bolts as the primary support with as needed inclined bolts, trusses, and cable bolts as secondary support. These two coal mining systems develop 3- and 4-way intersections during extraction processes. A study of Illinois (2004--2008) and US coal mines found that over 70% of roof falls occurred at intersections. It is therefore necessary to perform additional research in stress and displacement distributions around intersections and then design support systems to improve stability of intersections. This thesis research, in cooperation with a bolt supplier and NIOSH, analyses the stress and strain redistribution in and around intersections in typical lithologies in the Illinois Basin coal mines with the goal to develop a better understanding of failure initiation and propagation mechanisms with and without roof supports. Analyses were corroborated with field observations wherever possible. Non-linear continuum analyses using the Generalized Hoek-Brown failure criterion with rock mass properties is the foundation for these analyses. The first task (Task 1) toward these goals was to develop rock mass properties from available laboratory data using estimates of Geological Strength Index (GSI) for different lithologies. An important subtask was to perform an error analysis in estimates of rock mass properties assuming an amount of error in GSI estimates. Analyses and field observations were done for typical 4-way intersections at two mines in southern Illinois operating at depths of 150 m and 80 m, respectively in the No. 6 coal seam, which averages 1.8 m in thickness. Pre-mining horizontal stresses of 7.58 MPa and 4.13 MPa were applied in the E-W and N-S directions. These coal companies provided geologic logs and rock mechanics data for roof and floor strata. Rock mass engineering properties for different roof and floor lithologies were developed using estimated values of Geological Strength Index (GSI), and Hoek-Brown (H-B) rock mass failure parameters. A recent laboratory study provided normal and shear stiffness properties of the immediate roof interfaces within the bolting range of 1.8 m. MSHA-approved roof support plans were used for initial modeling. Short Encapsulation Pull Test (SEPT) data provided by bolt suppliers in the region were used to assign bolting system stiffness and strength parameters. Task 2 analyzed normal and shearing stresses and strains in and around mine intersections for typical pre-mining stress fields and then identified critical areas of failure initiation and progressive failure propagation. Failure initiation was hypothesized to occur for critical values of compressive (1 mm/m), tensile (0.5 mm/m), and shearing (0.5 mm/m) strains based on a review of laboratory stress-strain properties. This approach allows quantifying areas in and around an intersection where failures are likely to initiate with and without artificial supports. It computes three reinforcement factors with and without supports: reinforcement against tensile (RFT), compressive (RFC) and shearing (RFSS) strains. Task 3 assessed the performance of currently practiced roof support plans and identified where inadequacies exist and how they could be improved through spatial distribution of supports and their characteristics. Analyses were completed for two mines with one orientation of pre-mining horizontal stress field. The next logical step (Task 4) was to extend analyses in Task 3 to assess the effect of maximum compressive stress orientation in relation to entry direction (0° 30°, 60° & 90°) and different cut sequences and their effect on changes in failure initiation and failure propagation mechanisms. Numerical analyses have shown that stress and strain distributions are significantly different when the cut sequence is included in models. For a horizontal stress ratio of two (2), the 60° orientation provided maximum stability. Separate models with all cuts excavated simultaneously corresponded well with the well-established NIOSH software AHSM and previous research. The effect of cut sequence combined with the directional effect of pre-mining stresses becomes evident from the dissimilar results. A separate statistical study was conducted on 211 SEPT test data provided by a roof support manufacturer and marketing company in the region. Goals were to analyze the database for grip factor (GF) and anchorage stiffness (AS) characteristics using histograms and frequency distributions and, perform regression analyses to relate GF and AS values on the basis of height above coal seam and bolt diameter. Results were used for one stochastic run with variable GF and AS values assigned to different bolts in a roof control plan. Results indicated Gamma distribution best fitted AS and GF data. It was thought that the reinforcement factor for such a bolting layout would be more realistic than assigning a single value of GF and AS to bolts in the model.