H. Inanloo Arabi Shad; F. Sereshki; M. Ataei; M.d Karamoozian
Abstract
Investigation of effective parameters on mechanical and physical properties of ore deposits is very important in determination of their rock mechanic and failure properties. This investigation can be suitable in different mining operations such as drilling, blasting, comminution and mine planning. In ...
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Investigation of effective parameters on mechanical and physical properties of ore deposits is very important in determination of their rock mechanic and failure properties. This investigation can be suitable in different mining operations such as drilling, blasting, comminution and mine planning. In this paper, at first, microscopic sections were studied under different lights in Chadormalu iron ore mine. Then geomechanical and seismic properties as well as failure behaviour of the oxide ores (magnetite and hematite) were studied. The results demonstrated that the percentage of magnetite has a direct relationship with uniaxial compressive strength, tensile strength, Young modulus and P and S wave velocities; and the magnetite percentage has an inverse relationship with Poisson's ratio, porosity and saturation. Finally, the relation between magnetite percent and blast-induced preconditioning was investigated. The results showed that increasing the percentage of magnetite will increase the blast-induced preconditioning and increasing preconditioning decreased comminution processes in the Chadormalu iron ore mine. Also increasing the percentage of magnetite in feed of process factory from 25 to 50% decreases the power consumption from 70 (KWh/t) to 40 (KWh/t).
M. Ataei; S. H. Hoseinie
Abstract
Abrasivity, as one of the most important parameters has great influence on drilling rate. Up to now, four known methods such as "Rock Abrasiveness Index (RAI)", "Cerchar Abrasiveness Index (CAI)", "Schimazek's wear factor (F-abrasivity)" and "Bit Wear Index (BWI)" have been developed for evaluating of ...
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Abrasivity, as one of the most important parameters has great influence on drilling rate. Up to now, four known methods such as "Rock Abrasiveness Index (RAI)", "Cerchar Abrasiveness Index (CAI)", "Schimazek's wear factor (F-abrasivity)" and "Bit Wear Index (BWI)" have been developed for evaluating of rock abrasivity. In this paper, abrasivity of six rock types has been studied using Schimazek's wear factor and Rock Abrasiveness Index. For this purpose, equivalent quartz content and the mean size of rock grains have been calculated using thin section of rocks. All types of rocks have been tested view pointed of compressive and tensile strength (Brazilian test) in laboratory. For evaluating of drillability of rocks, the samples have been drilled using actual percussive-rotary drilling machine. Results reveal that by increasing Schmazek's wear factor, drilling rate decreases logarithmically and by increasing Rock Abrasiveness Index, drilling rate decreases exponentially.
A. Afsharian; Y. Naeimi; M. Ataei
Abstract
Slope stability studies is one of the most considerable parameter of safety and economical factors of open pits.
Because the pit walls usually consist of different characteristics of lithology and structure, using only one slope for all walls is not enough and reasonable.
So ...
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Slope stability studies is one of the most considerable parameter of safety and economical factors of open pits.
Because the pit walls usually consist of different characteristics of lithology and structure, using only one slope for all walls is not enough and reasonable.
So they need carefull geological and geotechnical studies to determine the geotechnical limits of the pit.
By using MRMR methods, SlopeW 2004 and FLAC 4.0 softwares and comparing the results,optimum slopes for North western wall of Chadormalu Iron mine have been calculated.
On the basis of all available data,the following geotechnical domains have been distinguished for North western wall of Chadormalu Iron mine:
• Lithology and Structure
• Pit Wall Orientation
• Rock Mass Rating and conditions
North western open pit wall is bounded by metasomatite, albite metasomatite, and ore. The structure of this domain is distinguished by steep normal faults with great displacement and brecciate limestone.The results of geotechnical boreholes, modeling and studies indicate that the overall slope of this domain could be increased from 52, to 60 degrees.
