Virtual Short Course
Deformation‐Based Support Design and Rockburst Hazard Assessment
By Peter K. Kaiser, Ming Cai and Dmitriy Malovichko
As mines go deeper and get larger, underground excavations become more vulnerable to damage, and mine designs become more fragile. Therefore, ground control and rock support increasingly dominate construction schedules and production performance. Efficient and effective support becomes a strategic element of asset management because mine infrastructure and extraction developments are the most significant investments in a modern mine, particularly in caving operations. This investment must be protected and maintained to reduce the risk of ground failure related production disruptions (Moss and Kaiser, 2021). Furthermore, many mining companies working at great depth have identified seismic hazard as a corporate risk and consider ground control with cost-effective support systems a tactical tool for risk management. For this reason, it is of critical importance to forecast future mine performance, anticipate potential operational disruptions and additional costs as well as the anticipated effectiveness of support to ensure workplace safety.
Deformation-based support design (DBSD), as outlined by Kaiser and Moss (2021), offers a rational support design approach that overcomes deficiencies of standard ground motion-centric and energy-based support design approaches. It also provides a means to anticipate the effectiveness of a chosen support system during the life of a mine.
This course focuses on support design for excavations in brittle rock when displacements induced by sudden stress‐fracturing may consume much of the support’s capacity. It deals with the functionality of the support in deforming ground and with the consequences of mining‐induced support damage. It offers quantitative means to estimate the capacity of integrated support systems and a systematic approach to compare it with the static and dynamic demands imposed on the rock support.
Who should attend
This course aims at corporate clients with practical and operational experience and will not cover fundamental principles of geo‐engineering. Due to the technical content, the course is suitable for ground control engineers and technicians as well as mine seismologists, geologist and planners operating in seismically active mines. Furthermore, the course is designed for geotechnical consultants serving seismically active mining operators.
This short course is presented in a virtual format in four modules covering both DBSD and RBHA. After an overview of design and evaluation procedures step‐by step instructions on how to adopt this innovative and integrated design approach are provided. Practical examples and case studies are used throughout the course to demonstrate the utility of DBSD and RBHA. Simplified analysis tools will be provided to the course participants to demonstrate the computation process and to facilitate sensitivity analyses.
Participants in this short course will be eligible for professional development (PD) hours (up to 16 hours). MIRARCO/Goodman School of Mines of Laurentian University can provide a certificate of attendance.
MIRARCO—Mining, Innovation, Rehabilitation and Applied Research Corporation, founded in 1998, is a not-for-profit applied research and technical service company formed through collaboration between Laurentian University and the private and public sectors. MIRARCO serves as an innovation bridge between researchers and industry.
The Goodman School of Mines serves as the gateway to Canada’s Mining University – Laurentian University. It is your one-stop access point to the most comprehensive mining education available in Canada, with an extensive array of undergraduate- and graduate- level programs, training and research geared to the full mining cycle.
How to register
For individual registration please click Register Course to register.
Discount is offered to corporations registering more than 3 individuals. Please send the names and email addresses of all participants from your organization to email@example.com to register for the course. MIRARCO will send one invoice for the group registration to your company.
Because gradual and sudden stress‐fracturing not only loads the support, but also deforms it, part of its load and energy dissipation capacity is gradually consumed leaving less and less remnant capacity at the time when the support is needed, i.e., during a rockburst. If the support capacity can be consumed by deformation, it can also be restored by preventive support maintenance (PSM). This concept for cost‐effective ground control is introduced and supported with operational evidence. Accounting for capacity consumption and integrating PSM into the mine development and operation schedule provide means for prudent asset management and opportunities for cost optimization.
Sudden stress‐fracturing of excavation walls emits seismic waves that can be used to identify the depth of strainbursting and the duration of the related rock mass bulking process. This provides essential input for support design in strainburst‐ prone ground, which is a new focus of this course.
The rockburst hazard in strainbursting ground depends on the stress level (stress at mining stages and strength in geological domains), the amount and rate of sudden stress fracturing, intensity of ground motion, and consumed support capacity (co‐seismic and mining‐induced strain). These and other factors are used to establish the current and to forecast the anticipated rockburst hazards. This is another new focus of this course.
This course presents an integrated approach of deformation‐ based support design (DBSD) using support demand and capacity assessment tools for areal support and bolting systems, and an innovative approach developed in collaboration with Newcrest Mining for rockburst hazard assessment (RBHA) using geological, stress, mining sequence, ground support, and seismic data.
Preliminary course outline
Each module involves three to four hours of presentations with active interactions presented in a virtual delivery format. As much as possible, the course material will be tailored to the needs of the participant or hosting company or to the common support technologies adopted at the operations of the attendees.
Detailed description of course modules (Time will be set aside for Q&A periods (20 to 30 min per module)
Module 1 - Introduction to DBSD and RBHA
- Rockbursts and excavation failure processes
- Deficiencies of common support design approaches
- Overview of DBSD principles
- DBSD steps to overcome limitations of common ground motion centric design approach
- Integrated RBHA approach
- Motivation and justification of change in design method and need for change management
- Estimation of support demand
- Bolting system; areal support for shakedown and strainbursts
- Sensitivity to input and design parameters
- Case examples: general design rules for demand estimation
- Sensitivity and probabilistic approach using simplified computational engines
Module 2 - Support selection and capacity estimation
- Selecting the “right bolt” and areal support
- How bolts work?
- Support component properties (test procedures and selecting proper design parameters)
- Estimation of remnant capacity of integrated support systems
- Areal support and sensitivity to bolt spacing
- Estimation of bolting system capacity and capacity consumption
- Integrated support systems with areal support
- Preventive support maintenance (PSM)
- Gabion concept and capacity estimation
- Simplified computational engine to assess sensitivity to variability to design inputs
Module 3 - Step‐by‐step procedures for support design analysis
- Bolt length determination
- Shakedown analyses
- Intersection design (Canadian Rockburst Support Handbook (CRBSHB’96) approach)
- New shakedown design approach
- Self‐initiated and dynamically loaded strainburst support evaluation
- Assessment of support effectiveness
- Forecasting support damage and effectiveness of PSM
- Deterministic and probabilistic approach for support damage hazard assessment
- Proof of concept of DBSD approach
- Verification using displacement measurements
Module 4 – Support performance and seismic hazard
- Step‐by‐step analyses using computational engines
- Safety margin assessment for case examples
- Introduction of Rockburst Hazard Assessment (RBHA) model
- Hazard forecasting for different design stages, scenario assessment, determination of probability of exceedance and annual rate of exceedance
- Demonstration on case examples
- Spatial variation considering domain dependent inputs (mine geometry, geology, stress and support
Prof. Peter Kaiser, Professor Emeritus, joined Laurentian University in 1987 as Professor of Mining Engineering and Chair for Rock Engineering and Ground Control at the Bharti School of Engineering. He was the founding President of MIRARCO and later was seconded to the Centre for Excellence in Mining Innovation (CEMI) as Founding Director and then as Director of the Rio Tinto Centre for Underground Mine Construction. He is a specialist in applied research for underground mining and construction and brings extensive experience from both the industrial and academic sectors and has served as a consultant to numerous consulting engineers, mines, and public agencies. He is a Fellow of the Engineering Institute of Canada (EIC) and the Canadian Academy of Engineers and in 2013 was awarded the Julian C. Smith Medal of the EIC for “Achievement in the Development of Canada”. He is the author of more than 400 geomechanics publications. In 2016, he has delivered the Muir Wood lecturer at the WTC and the MTS lecture at the 50th US Rock Mechanics Symposium, and in 2019 he presented the Mueller lecture at the ISRM congress in Brazil on a topic related to this course, i.e., on moving “From common to best practices in underground rock engineering”.
Prof. Ming Cai is the Geomechanics Research Chair in Laurentian University’s School of Engineering. Prior to joining Laurentian, he was a member of the Mansour Group Inc., MIRARCO, GRC, Tokyo Electric Power Services Ltd., and Tsinghua University and brings over 20 years’ research, education, and industry experience. He has a wide variety of interests in rock mechanics and rock engineering, and has made technical and scientific contributions to the advancement of rock engineering, including constitutive modeling of rock masses, rock mass characterization, rock support, interpretation of AE and microseismic monitoring data, and rock failure process simulation, etc. Dr. Cai is the author/co-author of over 200 publications. He is a recipient of the John Franklin Award in Rock Mechanics from the Canadian Geotechnical Society. Currently, he serves as an editorial board member for six international journals in the fields of rock mechanics and rock engineering.
Dr. Dmitriy Malovichko is the Director and Head of Applied Seismology of IMS. He has a PhD in Physics and Mathematical Science from the Institute of Physics of the Earth (Moscow, Russia). From 2000 until 2009 he worked at the Mining Institute (Perm, Russia) and was involved in regional seismic monitoring, local seismic observations in potash mines and karst caves, and engineering seismology projects. In 2009 he joined ISSI (South Africa), which later became the Institute of Mine Seismology (South Africa, Australia and Canada). He is responsible for seismological services for mines (processing and interpretation of seismicity, investigation of large or damaging seismic events) and is involved in research projects in mine seismology.
Dmitriy is interested in inferring information about seismic sources from seismic signals, the integration of seismic monitoring data with stress modelling, and the assessment of seismic and ground motion hazards associated with planned mining.