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By R. Romano, E. Montalar, J. B. Serón

The SMR geomechanics classification system (adaptation of RMR for slopes) is reviewed with data from 87 actual slopes in Valencia. In a research project, SMR has been applied by a GIS system, as a method to forecast stability problems in future road construction. As a result of this work a methodology for GIS application has been developed. On revient sur la classification geomechanique SMR ( une adaptation du RMR pour talus et pentes) avec les dates de 87 talus existant autour de Valencia. Dans le cadre d’un projet de recherche SMR a été appliquée, avec un système GIS, comme méthode de prévision de stabilité problèmes dans la construction de futures routes. Une méthodologie pour l’application du GIS a été développe. Das Geomechanische Einteilungssystem SMR (eine Anpassung des RMR an Böschungen) wird an Hand der Daten von 87 Böschungen im Gebiet von Valencia überdacht. In einem Forschungsprojekt wurde das SMR in einem Geographischen Informationssystem (GIS) als Methode zur Vorhersage von Stabilitätsproblemen bei zukünftigen Straßenbauprojekten eingesetzt. Das Ergebnis dieser Arbeit ist die Entwicklung einer Methodologie für die GIS-Anwendung

Jan 1, 2003

By C. Sarkar

Increased competition in today’s global economy has put mineral industry under excessive pressure to effectively manage production assets to generate business wealth. Capital intensive industry (CII) organizations are seeking ways to manage skill resources, internal processes, and organizational networks with a view to reduce the cost of ownership of assets and increase efficiency of operations and service. The emerging concept of Enterprise Asset Management(EAM) is a collection of business processes that allow CII with right focus on return on investment on assets, to make right decisions on planning, acquisition, maintenance, operation, rehabilitation, and disposal of assets. Information technology (IT) can drive significant returns if the infrastructure covers seamlessly all business processes and all systems, like geographic information system, maintenance management, investment management, laboratory information management, and supervisory control and data acquisition system. The simple approach to IT in the past with disconnected silos of technology, information, and business processes cannot deliver the expected benefits under the modern business environment. Identification of business and application component is a prerequisite for the development of an asset management system that links effectively disciplined processes having characteristics of agility, speed, and integration. This paper discusses various issues and outlines the steps for developing an asset management roadmap in an organizsation. It also presents major business and application components of the system. Keywords: Enterprise asset management, Business architecture, Business component, Application component, Asset ownership, Asset operations, Information technology, Capital Intensive industry

Jan 1, 2003

By A. F. S. Schoukens

The Mintek Thermal Magnesium Process (MTMP) was successfully demonstrated in November 2004. The pilot plant was operated continuously for 8 days, during which about 30 tons of magnesium producing recipe was smelted in a DC (direct-current) arc furnace at a feed rate of 525 kg/h. The furnace was operated at power levels of 700 to 850 kW, resulting in slag tapping temperatures of 1600 to 1700°C. Magnesium extraction averaged 77 per cent and was as high as 85 per cent during good extraction periods. The furnace generated 70 to 85 kg/h magnesium vapour that was delivered to the condenser where the temperature was controlled at 680 to 720°C. The novel condenser captured the magnesium in a liquid state, which was tapped periodically as required. In total, 15 magnesium-tapping operations were carried out, proving that online magnesium tapping can be consistently performed without any major difficulty. About 3500 kg of crude magnesium was produced with a quality that was similar to, if not better than, that of the Magnetherm?s crude metal. The condensation efficiency averaged 85 per cent, and peaked at 87 per cent, which exceeded the target of 80 per cent set for the pilot scale. A brief magnesium market study was also carried out. Magnesium demand is expected to keep on growing by 6 to 8 percent over the next 10 years and could reach 2 million tons by the year 2020. The growth will be mainly in the die-casting sector for light-weight automotive applications. China is likely to remain the dominant supplier of primary magnesium but competitively priced non-Chinese magnesium producers will be needed to sustain the anticipated growth of 6 to 8 per cent over the next 10 years. In addition, a prefeasibility study was undertaken for a commercial plant. The study confirmed the relatively low capitalcosts of the MTMP process, as well as the competitiveness of theoperating costs, as compared to the industrial electrolytic process.

Jan 1, 2006

By L. Robles-Stefoni

"Multiple-point simulation (MPS) methods have been developed over the last decade as a means of reproducing complex geological patterns while generating stochastic simulations. Some geological spatial configurations are complex, such as the spatial geometries and patterns of diamondbearing kimberlite pipes and their internal facies controlling diamond quality and distribution.Two MPS methods were tested for modelling the geology of a diamond pipe located at the Ekati mine, NT, Canada. These are the single normal equation simulation algorithm SNESIM, which captures different patterns from a training image (TI), and the filter simulation algorithm FILTERSIM, which classifies the patterns founded on the TI. Both methods were tested in the stochastic simulation of a four-category geology model: crater, diatreme, xenoliths, and host rock. Soft information about the location of host rock was also used. The validation of the simulation results shows a reasonable reproduction of the geometry and data proportions for all geological units considered; the validation of spatial statistics, however, shows that although simulated realizations from both methods reasonably reproduce the fourth-order spatial statistics of the TI, they do not reproduce well the same spatial statistics of the available data (when this differs from the TI). An interesting observation is that SNESIM better imitated the shape of the pipe, while FILTERSIM yielded a better reproduction of the xenolith bodies. IntroductionThe simulation of geological units poses several technical problems that challenge the capabilities of available geostatistical simulation approaches and their ability to deal with spatial complexity of categorical variables. The spatial geometry of diamondbearing pipes and their internal facies controlling diamond distributions are a specific and well-known difficult modelling problem. The geometry of a kimberlite pipe is typically like an inverted cone (Figure 1); the wider part is known as the crater and is located near the surface, and the narrower, deeper part is known as the diatreme. Xenolith bodies can also be found inside the pipe. A very important contribution to the geological modelling of the contours of the pipe is the measure of uncertainty about the location of the contact between the kimberlite pipe and the host rock."

Jan 1, 2016

By L. Mabiza

Keywords: Pyrometallurgy, circular furnace, PGM, platinum, Peirce-Smith converter, Zimbabwe The Zimplats Smelter, located on the northern part of the Great Dyke, at the Selous Metallurgical Complex, is the only PGM smelter in Zimbabwe. Zimplats? operations currently consist of the Ngezi Platinum Mine, which is a 1.5 Mt/a open-cast and 0.7 Mt/a underground mine, and a Concentrator and Smelter to which ore is transported 80 km by road. The final converter matte product is transported to Impala Refining Services in South Africa for refining and marketing. The Zimplats Smelter operations consist of a concentrate filtration plant, a Drytech flash dryer, a modified Elkem / Hatch 13.5 MVA circular furnace, two 10? x 15? Peirce-Smith converters, and a matte granulation plant. The Zimplats smelter uses a three-field electrostatic precipitator, supplied by ELB-Brandt, for removal of particulates in the gas streams from both the converter and furnace. Construction of the smelter commenced in 1995, under the BHP / Delta Gold of Australia joint venture. The furnace was lined mid-1996, and smelting operations commenced in 1997. Due to design challenges, the Elkem furnace was modified by Hatch in 1998, and the smelter had not reached full capacity when operations were suspended in 1999. Re-commissioning took place in January 2002.

Jan 1, 2006

By G. Apsey

Eutectic freeze crystallization (EFC) is a novel technique for the recovery of pure salt and pure water from hypersaline waste brines. It is therefore a promising technology for the treatment of industrial waste waters. The impurities caused by crystallizing salt out of multi-component brines by EFC have not yet been investigated, however. To these ends, the selenium impurity found in sodium sulphate, produced from the waste brine of a platinum operation, was investigated. It was believed that the similarity between sulphate and selenate ions allowed isomorphous substitution of selenate ions into the sodium sulphate crystals, which was the likely cause of impurity uptake. It was found that the presence of sodium chloride in the industrial brine promotes the uptake of selenium, while ionic strength of the brine and mass deposition rate of sodium sulphate did not have a significant effect on the selenium uptake. Isomorphous substitution is predicted to be the most significant mechanism by which all impurities will be taken up when applying EFC to other industrial waste brines.

Jan 1, 2013

By M. Castelli, C. Scavia, S. Marello, A. Allodi

ABSTRACT – This paper investigates the possibility of interpreting the shear band evolution in hard soils and soft rocks as the result of shear propagation from pre-existing natural defects. Thesis done through the application of the principles of Fracture Mechanics, a Slip-Weakening Model(SWM) being used to simulate the non-linear zone at the tips of the discontinuity. Experimental observations have been carried out on prismatic samples of Beaucaire marl through biaxial compression tests in plane strain conditions. A numerical simulation confirms the validity of the proposed approach. RÉSUMÉ – Cet article présente la possibilité d’interpréter l’évolution des bandes de cisaillement dans les roches tendres et les sols raides comme le résultat de la propagation pour cisaillement à partir d’un défaut préexistant. Le Slip-Weakening Model (SWM) a été employé pour modéliser la zone non linéaire a l’extrémité d’une discontinuité. Nous présentons des observations expérimentaux obtenues à travers des essais de compression en déformation plane sur des échantillons prismatiques de marne. La simulation numérique d’un essai confirme la validité de la méthode proposée. KURZFASSUNG – Die vorliegende Arbeit versucht die Ausbreitung von Scherzonen in(bindigen) Böden und im Lockergestein anhand der Entwicklung von Scherrissen ausgehend vonexistierenden Schwachstellen zu erklären. Die Umsetzung erfolgte mit Hilfe der Bruchmechanik,für die Modellierung der nichtlinearen Zone an den Rissenden wurde ein Slip-Weakening-Modell(SWM) eingesetzt. Es wurden zweiaxiale Druckversuche an prismatischen Probekörpern vonBeaucaire Mergel unter der Bedingung eines ebenen Verzerrungszustandes durchgeführt. Dienumerische Untersuchungen bestätigten die Annahmen der untersuchten Theorie.

Jan 1, 2003

By Arun Vathavooran, Adrian Singh, Michael Fletcher, Rainer Imhof

The Imhoflot G-Cell, a new development in the pneumatic flotation technology (which incorporates centrifugal forces in the separating vessel) is a recent innovation in the mineral processing world. The G-Cell was invented by Dr Rainer Imhof and commercialised by Maelgwyn Mineral Services Ltd. In a short time span a number of plants and units have been successfully commissioned in the mineral processing industry. In addition, a number of industrial G-Cell flotation plants are in the process of construction for the purpose of coal preparation and environmental remediation. In this paper two industrial installations have been highlighted together with a pilot plant test programme investigating ultra fine flotation recovery for a base metal operation.

Jan 1, 2007

By K. Coleman, C. Visser, N. Selby, X. W. Pan, T. Letwaba

A prototype weightometer soft sensor is under development at DebTech, De Beers in partnership with Venetia Mine. Its main function consists of an online data source; data validation; dynamic weightometer models; online detection of weightometer failure; alarming and replacing a weightometer when it fails. 31 dynamic models have been developed. All models with R2>= 85%are accepted as good models and they generally have satisfactory results with a daily error of less than 8% within 90% confidence level. By using those models, a set of soft sensors can be set up to cover all weightometers in the entire processes starting from primary crushing to the stock piles of dense medium separation (DMS). Some practical issues and concerns on model development are discussed, including data collection, data analysis, data pre-processing, variable selection, time delay, model training and model validation. When deploying the weightometer soft sensor system, the potential benefits could include: reduction in plant downtime; reduction in unplanned maintenance and even replacement of non-critical weightometers, particularly where nuclear weightometers are used. Keywords: soft sensor, weightometer, dynamic modelling, neural network modelling

Jan 1, 2003

By G. L. Smith

This paper consolidates the key elements of seven contributions, on strategic long-term planning, to two of the three international conferences on Strategic versus Tactical approaches in Mining held over the period 2005?2008. The holistic concept of strategic long-term planning as developed and implemented at Anglo Platinum is described. Consideration is given to the planning cycle, principles supporting the construction of the long-term plan, and aspects of unique best practice as developed in Anglo Platinum. Further description of Anglo Platinum?s approach to corporate governance, including the processes, methodology, systems, unique tools and techniques that are applied to value and select capital investment options is also given.

Jan 1, 2009

By N. Barton, E. Quadros

This paper addresses the prediction of groutable joint apertures, grout penetration limitations, and possible grout take volumes per cubic metre of rock, as a result of 5 to 10 MPa pre-injection pressures ahead of tunnels. Joints are obviously opened more than in the preceding Lugeon tests, and many rock mass properties can apparently be improved if stable micro-cement based materials are used. Cet article concerne la prédiction des ouvertures des fractures injectables, les limites de pénétration du coulis et les volumes injectés par mètre cube, d’après les résultats des injections à l’avant tête des tunnels sous pressions de 5 à 10 MPa. Evidemment les joints s’ouvrent plus que dans les essais Lugeon précédents. Maintes propriétés du massif peuvent apparemment être améliorés si l’on emploi des coulis a base de micro-ciment stable. Die Publikation widmet sich der Prognose injizierbarer Kluftöffnungen, Grenzwerte für Injektionsreichweiten und erreichbarer Injektionsvolumen pro Kubikmeter injizierter Fels, durch die Anwendung von 5 bis 10 MPa Vorinjektionsdrücken vor der Tunnelfront.Die Klüfte werden offensichtlich weiter geöffnet als in den vorhergegangenen Lugeon Versuchen und mehrere Felsparameter können durch die Verwendung von stabilisierten Micro-Zement basierten Injektionsmaterialien verbessert werden.

Jan 1, 2003

By S. D. Dladla, S. Ramsamy

The majority of the tailings dam operations in South Africa will be required to comply with the new Global Industry Standard on Tailings Management (GISTM) within the next one to three years, depending on the dam classification and the requirements of the respective investors and insurers. With up to 72 auditable requirements, the implementation of the Standard needs careful planning and prioritization. This paper focuses on the practical steps to GISTM compliance for tailings facilities in operation in South Africa. The discussions are based on current practices, South African regulations, and industry standards requirements. The possible changes in dam classifications and the associated requirements are presented.

Jun 2, 2022

By T. A. Muhlare

"Large quantities of slag are produced every year and dumped on slag heaps around the world, posing a potential environmental threat due to contained heavy metals content. Slags are waste minerals produced during furnace smelting of minerals. The contained values of base metals may be released into the environment under natural weathering conditions polluting ground and underground water. Copper losses into slag are a continuous problem in pyrometallurgical smelting operations. Due to shortage of ore concentrate, various mining operations have initiated the recovery of copper from dumped slag. The typical process uses crushing, milling and flotation. These operations create excessive liner wear rates during crushing and milling because the bond work index of copper slag is 22 kWh/t and this is considered a very hard slag. The process also has reduced flotation recoveries and requires high flotation reagent consumption. The present work shows that digestion of the milled copper slag slurry with concentrated sulphuric acid at a temperature of 250oC forms a solid cake and leaching of the solid cake with water is a possible option. However, the consumption of sulphuric acid can have a considerable cost on the recovery process. This can be limited by producing a leach residue containing gypsum and silicate materials as amorphous silica which are suitable for use as an additive for Portland cement. Laboratory results show that 90% copper recoveries can be achieved. The leaching is conducted to prevent silica gel formation and iron co-extraction. Leaching is optimum if silica gel-free solutions and good filterable residue are obtained. INTRODUCTION Slag is a waste by-product of smelting and converting operations in metallurgical plants. Both smelting and converting operations are aimed at iron separation from base metal sulphides in non-ferrous metallurgy. The iron sulphide component of the ore or concentrate is oxidized to iron oxide at higher temperatures in the molten form, and then fluxed with silica and other oxide rock minerals to produce fayalite (2FeO•SiO2) slag (Schlesinger et al., 2011). Slags are generally deposited on dumps and considered to be unreactive materials. Smelter copper slag contains significant concentrations of several potentially toxic elements, including arsenic, lead, cadmium, barium, zinc and copper. These elements can be released into the environment under natural weathering conditions and cause pollution of soils, surface waters and groundwater (David, 1998)."

Jan 1, 2015

By J. van der Merwe, D. Tharandt

The corrosion behaviour of 304L stainless steel laser-cladded with various amounts of ruthenium (Ru) was evaluated in solutions of sulphuric acid and sulphuric acid plus sodium chloride at 25°C and 45°C by open-circuit potential and cyclic potentiodynamic polarization tests. In general, the addition of Ru to the stainless steel increased its corrosion resistance in 1 M H2SO4, as well as in 1 M H2SO4 plus 1 wt% NaCl. This was observed for a number of parameters such as corrosion rate, corrosion potential, open-circuit potential, and current density. However, increasing the amount of Ru added beyond a certain level did not result in further improvement in corrosion protection. For each environment there is an optimal Ru concentration for the best corrosion protection. For example, in 1 M H2SO4 at 25°C, 2.44 wt% Ru shows the least active surface in terms of corrosion. Further research into ruthenium coatings on stainless steels is recommended.

Jan 1, 2015

By M. Paricheh, M. Rahmanpour

"The cost efficiency and high reliability of semi-mobile or combined in-pit crushing-conveying (IPCC) and truck systems, compared to conventional truck-shovel systems alone, make them more attractive for use in modern mining operations. Semi-mobile systems, which are the most common systems in open-pit mining, combine the advantages of both systems such that fewer trucks are required, operating costs are lowered, and the operation is environmentally sound. One major aspect of utilizing this system is determining the location of the in-pit crusher and the timing of relocations. Facility location models are rarely used in the mining sector, but these models may be used for solving the in-pit crusher location problem. To this end, the main parameters affecting the IPCC location in open pit mines are reviewed and examples given of how they are applied to a dynamic location-relocation problem. Subsequently, the model is implemented for Sungun copper mine in Iran and the number and the exact time of relocations of the IPCC units determined. IntroductionNowadays, compared to the last century, metal prices are more volatile, average and cut-off grades have decreased, and stripping ratios increased. From a mining engineering point of view, many ore deposits with simple access and low capital and operating costs have been exhausted. The remaining deposits are located at depth, with no easy access, which requires high initial capital costs (Osanloo, 2012). Mining at great depths and high tonnages is possible only through open pit mining. Today, more than 80% of open pit mines in the world use a shovel-truck system for loading-hauling operations (Osanloo, 2010).With increasing depth, haulage distances increase and the number of loads per truck decreases. As a result, fuel, tyre, and depreciation costs per ton increase. Owing to these factors, open pit mining at great depth (300 to 1000 m) using shovel-truck systems faces some technical and economic problems. In-pit crushing-conveying (IPCC) systems have been known in the mining industry for many decades. The idea was introduced in 1956 in Germany. Today, the cost efficiency and high reliability of IPCC make it more appealing than conventional shovel-truck operation, especially in longer life projects with lengthy transportation distances and high production rates (Koehler, 2003). Since 1956, different aspects of this system have been reviewed by many researchers. Barua and Lanergan (1985) developed a computer program that compares the tonnage aspects of various conveyor layouts. They believed that to maximize the economic benefit of lower haulage costs associated with in-pit conveying, one must first minimize the cost of the flatter slope, which is expressed in terms of additional stripping or tied-up ore. Dos Santos and Stanisic (1987) evaluated the design of a high-angle conveyor at the Majdanpek copper mine. Then, Sturgul (1987) applied GPSS (general purpose simulation system) to find the best location of an in-pit crusher."

Jan 1, 2017

By K. Richardson

Although the De Beers group has a long history of placer mining on land, the group only became actively involved in deep water marine diamond exploration and mining in 1983 with the formation of DeBeers Marine. Full-scale commercial mining commenced around1991. Since then, the group marine mining capability has grown into a formidable fleet of 8 large deep water (>70 m) mining vessels, as well as other special purpose geosurvey platforms. Marine diamond production by the group is expected to be just short of 1 million carats in 2006. De Beers operates across the entire value-chain spectrum from geology and geosurvey, through sampling to mining, and finally ore processing into high value concentrate. Supporting these operations involves significant service activities such as maintenance, security, logistics and environmental management. Specific challenges exist in terms of developing or acquiring appropriate technology for marine mining. These challenges have resulted in De Beers operating extensive in-house R&D and projects departments, as well as drawing extensively from technology partners. An array of computational and test facilities is also available to support R&D and projects activities. Hydrotransport in various guises is key to the current approaches to marine mining and ore processing. Use is made of airlift and centrifugal pumping for hydraulic hoisting of very coarse gravel, while splitters, launders, dewatering, elutriators, jet pumps, centrifugal pumps, dense medium circuits, pipeline systems, and instrumentation for coarse abrasive particles are used extensively in the ore processing plant.

Jan 1, 2007

By N. Hanief

This research involves the investigation of phase transformations in the platinum-chromium coated system. Single-layer 0.1 µm platinum coatings were deposited via electron beam deposition on 99.98 percent pure chromium substrates. Specimens were subjected to systematic heat treatment in a vacuum furnace at 900°C for up to 20 hours. Phase formation and the changes in surface morphology were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM).Both CrPt and Cr3Pt phases are formed during heat treatment for different times at 900°C. Significant changes in the morphology of this coated system were detected after heat treatment at 900°C for 20 hours.

Jan 1, 2012

By J. G. van der Watt

Due to increasing concerns of global rare earth element shortfalls in the near future, possible alternative sources of rare earth elements have recently become of economic interest. One such alternative is decanting acid mine water originating primarily from abandoned old mines in the Witwatersrand region of the Republic of South Africa. In this study, a novel way of rare earth element removal from the acid mine drainage was employed, making use of bentonite clay, which has very good adsorbent properties, as a rare earth element carrier material. The process can be economically viable only, if the elements can be selectively removed from the bentonite clay carrier material so as to yield reusable clay. Acid leaching was proposed to liberate the adsorbed rare earth elements from the bentonite clay. Accordingly, acid leaching experiments were performed to study the desorption of three commonly-found rare earth elements, namely neodymium, samarium, and dysprosium, from bentonite clay in the presence of sulphuric and hydrochloric acid. It was established that the three rare earth element species could be selectively removed as a group from iron, magnesium, and manganese metals through the careful manipulation of the pH. An investigation into the kinetic aspects of the rare earth element desorption process from the bentonite clay was also undertaken. The applicability of various kinetic models such as zero-order, pseudo first-order, pseudo second-order, elovich, parabolic diffusion, and power function were tested to describe the time-dependent desorption of rare earth elements from bentonite clay. It was determined that the pseudo second-order kinetic model represented the dissolution processes for neodymium, samarium, and dysprosium from bentonite clay the most accurately.

Jan 1, 2012

By L. Arnberg, E. Ott

The microstructure of ferrosilicon is important since it controls the disintegration of the material during crushing and thus the generation of fines. Therefore a study of the microstructure formation during solidification of pure FeSi(75wt%Si) and FeSi(75wt%Si) containing 1.2wt%Al and 0.2wt%Ca has been initiated. The material has been cast into rods of 8mm diameter, which have been remolten by induction heating and directionally solidified in a Bridgman apparatus. This allows the temperature gradient and the growth rate to be controlled independently. The temperature history during solidification has been recorded by a thermocouple in the melt. Growth rates have been varied between 5 and 400µms-1 and temperature gradients between 3 and 14°Kmm-1. The microstructures show a large dependence on the solidification conditions. The crack formation in the alloys has been studied and found to be strongly related to the microstructure.

Jan 1, 2004

By K. Sugawara, Y. Hirakawa, A. Sato

The rock mass properties such as deformability and permeability are highly dependent on the existence of cracks. The Ratio of Crack Opening Dependency (RCOD) was proposed as a new index to evaluate the deformability of infinite jointed rock mass. The RCOD is defined as the ratio of total amount of crack opening and the total deformation of jointed rock mass. The theoretical relation between the RCOD and the effective compliance of jointed rock mass is discussed and confirmed through two-dimensional numerical analysis by the SC-DDM, together with the applicability to the rock engineering. Les propriétés de masse rocheuse telles que la déformabilité et la perméabilité sont très dépendantes de l'existence de fissures. Le rapport de dépendance d'ouverture des fissures a été proposé comme un nouvel index d'évaluation de la déformabilité de masse rocheuse à assemblage infini. Le rapport de dépendance d'ouverture des fissures est défini comme étant le pourcentage de quantité totale d'ouverture des fissures et de déformation totale de la masse rocheuse assemblée. Le rapport théorique entre le rapport de dépendance d'ouverture des fissures et la compliance efficace de masse rocheuse assemblée sont traités et confirmés au travers d'une analyse numérique à deux dimensions par SC-DDM en même temps que l'applicabilité à l'ingénierie des roches. Die Felsmasseneigenschaften wie Verformbarkeit und Durchlässigkeit sind hochgradig abhängig von dem Vorhandensein von Rissen. Das Verhältnis der Riss-Öffnungsabhängigkeit (RCOD) wurde als neuer Index der Verformbargkeit von infinit zerklüfteter Felsmasse vorgeschlagen. Der RCOD wird als Verhältnis der Gesamtmenge der Rissöffnungen und der Gesamtverformung der zerklüfteten Felsmasse definiert. Die theoretische Beziehung zwischen RCOD und der effektiven Verformbarkeit von zerklüfteter Felsmasse wird diskutiert und durch zweidimensionale numerische Analyse mit SC-DDM bestätigt, zusammen mit der Anwendbarkeit auf Bergbautechnik.

Jan 1, 2003