Related Papers
Cave mining design methodology for use in challenging geomechanics environments
2017 •
Marko Didyk
Underground cave mining design tends to rely upon empirical and numerical models, neither of which are able to close the engineering design loop. Such circumstances, mean that it is very difficult to analyse with certainty, the causes of significant problems that can arise from time to time. Widespread collapses and damaging mining-induced seismicity, have occurred, for example, within the El Teniente mine, and are examples of cave mining problems that appear to have been without resolution. Further, fundamental and relevant engineering design issues tend to be lost in a swathe of other issues, which have only minor importance, in comparison to the major concern in cave mining – that of long-term stability and productivity of the production complex. Cave mining design methodology put forward in this paper is based upon the fundamental precepts that: a detailed and in-depth knowledge and understanding of the geomechanics mechanisms involved in the response of the rock mass to the cre...
Geomechanical Challenges: Practices and Innovations
2018 •
MANOHAR VILADKAR
After briefly reviewing the past and the current status in geotechnical engineering, an attempt has been made here to discuss three case studies related to extreme loading conditions like impact and blast loading, extreme wind loading and severe squeezing ground condition in lower Himalaya. These were really very challenging problems and some innovative solutions were provided which were implemented in the field. Subsequently, attempt has also been made to identify some of the more challenging problems which are basically coupled, multi-physics–multi-mechanics problems. To undertake such problems, however, there is a need to widen the scope of geotechnical engineering into a wider area of geo-engineering.
Empirical methods in mining geomechanics – Reflections on current state-of-the-art
Fidelis Suorineni
Geomechanics rely greatly on empirical methods for excavation design as a means of overcoming the complex nature of the rockmass and the associated difficulties in defining its constitutive behaviour. These empirical methods include the Rockmass Rating (RMR) systems (Bieniawski, 1973), the Tunnelling Quality Index (TQI) or Q-system Barton et al. (1974), Mining Rockmass Rating (MRMR) system (Laubscher & Taylor 1976), The Geological Strength Index (GSI) (Hoek 1994), Hard rock pillar desigm chart (Lunder and Pakalnis, 1997), The Equivalent Linear Overbreak Sloughage (ELOS) stabil-ity graph (Clark & Pakalnis 1997), the cavability prediction chart (Laubscher, 1994) and the Hoek and Brown failure criterion (Hoek & Brown, 1980). This paper gives credit to the developers of these methods who through their diligence and observation brought some sanity to somehow various chaotic periods in the history of mining geomechanics. Current state-of-the-art shows some of these methods, while valid at...
Dealing with Uncertainty and Risk in Rock Engineering Design
2018 •
William Joughin
A method for risk-based design is described in this paper. Probabilistic methods of analysis are applied to stress modelling to determine the probability of exceeding a given depth of failure. Suggestions are provided for dealing with geotechnical uncertainty. The understanding of aleatory variability can be improved by collecting more data and improving the quality of data through training and quality control. Stress and model uncertainty remains a challenge in geotechnical engineering. Some degree of subjective engineering judgment will therefore always be required in geotechnical design. Acceptance criteria then need to be defined in terms of safety and economic risk. Corporate risk matrices can be used for assessing the risk in terms of the probability and consequence. International safety benchmarking and safety milestones should be considered. The cost of rehabilitation of tunnels and the financial losses due to lost production are assessed using the model. A typical risk matr...
Int. J. Rock Mech. & Geomech.
Technical Notes: Geomechanics versus Rock Mechanics
2016 •
Petru CIOBANU
The idea that one of these areas of study, either Geomechanics, or Rock Mechanics, is included entirely into the other, or that it is a division of the other is mistaken. Both share common units of study (chapters, sections and topics), but they also have distinct sections, found in only one of them. This technical note presents the author's views about what should be included into the two areas (disciplines and sciences), both in their shared area of study, and in the specific sections, distinct to each of them. From a mechanical point of view - in general, the rocks are subject to various natural phenomena and /or technological processes taking place on an industrial scale or as an experiment, which may cause mechanical or mechanical effects. Therefore, phenomena and processes of this kind can be classified into two categories: - mechanical, the displacements, deflections and / or modification of the properties of rocks caused by the action of forces and / or pressures (eg, compaction under the weight of the rock layers above); - non-mechanical (physical, chemical), but with mechanical consequences that have as a result either the emergence of new tension states or the modification of the existing mechanical properties and parameters. An example of this is the phenomenon of swelling that increases the volume of shale layers and, under in situ conditions, generates additional pressure on surrounding rock layers.
Tomorrow’s geotechnical toolbox: design of geotechnical structures according to EN 1997:202x
2019 •
Jose Estaire
Rock Mechanics and Rock Engineering
Putting Geological Focus Back into Rock Engineering Design
2020 •
Trevor Carter
Geosynthetics risk-based design in mining
2014 •
Franco Oboni
Geosynthetics used in mining applications are subjected to harsh environments, yet in some cases are supposed to last forever. It is likely that geosynthetics will, sooner or later, fail due to harsh conditions, chemical/UV degradation, or re-polymerization under stress. In the short term, the probability of failure is dictated, as for any geostructure, by the variability of geo-materials parameters, variability of loading, duration of required performance, and site-specific conditions. The short-term design problem can be thought of as a “standard” geotechnical exercise, where standard risk-based decision-making (RBDM) approaches may be beneficial. On the basis of available knowledge, it is difficult to determine the longterm probability of failure of the geosynthetics and the structures incorporating them. The only thing we know is that it is likely they will, sooner or later fail; similarly to any other material, the longer the life span of the proposed structure, the higher the ...
Geotechnics in the 21st Century, uncertainties and other challenges, with particular references to landslide hazard and risk assessment
2012 •
Robin Chowdhury
Rock Mechanics
franco pomacosi
