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The problem studied in this paper is that of designing the optimal open pit haulage ramp that, for a given ramp width and a maximum ramp gradient, connects two …
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Ramps (or declines) are often used in underground mines to transport ore, waste, materials, and person- nel. This paper studies mine ramp productivity and presents results from a set of computer ...
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they can be classified into straight ramp, spiral ramp, and zigzag ramp. Main Ramp The ramp is mainly used for delivering ore. Advantages of main ramp in underground mine: (1) It is less affected by terrain, surface industrial site, and rock stratum conditions, there is no hoisting equipment on ground surface, and the
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4 times the width of the hauling equipment. The ramp gradient is constrained by a maximum gradient determined by diverse factors such as the type of hauling trucks, the mining operation conditions and the road surface quality. Mining trucks work best when the maximum ramp gradient is between 8% and 10% (Thompson, 2011).
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The proposed model assumes that ramp links are straight lines, so the proposed theory and algorithm can only be applied directly to underground mines in which terminal points are in a near-horizontal plane to satisfy the gradient constraint, i.e., they cannot be used in mines with several production levels.
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Slope. The slope of ramp in the longitudinal direction. To determine the ramp slope, various factors must be taken into accounts, such as technical performance of trackless equipment, purpose and type of ramp, transport volume, and service life. The slope of a ramp is usually 7–20%. The slope of a curved segment can be decreased as …
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Mine design is an interative and continual process. In the early stages of development, mine design may change frequently due to exploration drilling of the ore body. ... Inter-ramp Angle: the angle between the toe of a slope where a ramp segment passes and the toe of a bench located immediately upwards. Overall Slope Angle: ...
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Appropriate working, inter-ramp and final slope angles. Based on these considerations, the mine planner proceeds to design phases ensuring that ramp access to each active …
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3.1 Visits to mines 3.1.1 Questioner A questioner was circulated to mines to determine the type, size and number of vehicles used in industry. This questioner was circulated through the technical committee of SIMRAC. No feedback was however received. 3.1.2 Visits Different mines were visited to determine the different trackless mobile mining
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A Schematic Example for an Indoor Ramp. Likewise, the percentages for the slopes of interior ramps allow for a 10% slope only to overcome very small heights, such as a step of up to 30 centimeters ...
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in the mine. The absolute value of the gradient of each ramp is constrained to be within a safe climbing limit for trucks, typically in the range 1:9 to 1:6.5. Hence the decline network is gradient constrained with a given max-imum absolute value for the slope. In addition, there is a minimum turning radius for curved ramps which is typi-
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In this paper, we present a methodology to assist the ramp design in underground mining, minimizing both development and operational costs. The methodology considers an …
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the maximum tolerable slope in the construction of the ramp that the equipment can operate. development costs of ramps and crosscuts. operational costs of ramps and crosscuts ... The haulage cost of all the mine production for 1 meter of ramp that must pass on level k (C_{H2e}^{{}}) The haulage cost of the production of the …
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Specifically issues like: • Should my ramp be clock-wise or anti-clockwise? • What gradient ramp should I be using? • What radius …
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By assimilating a ramp as a curve consisting of segment and circumference sections, they can optimize the ramp's shape to a fixed curvature and gradient, end …
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gradient of spiral ramps for mines - rachunkowosc-promed.pl. Optimum ramp design in open pit mines Mining trucks work best when the maximum ramp gradient is between 8% and 10% (Thompson, 2011) Once the design parameters have been defined, engineers must decide whether to use spiral ramps, switchbacks (180 ∘ turns) or a combination of …
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an underground mine is a decline (a system of ramps and drives with path topology) connecting the access and draw points with the surface portal (exit) or breakout ... ity requirement is that the absolute value of the gradient of each ramp is constrained to be within a safe climb-ing limit for trucks, typically in the range 1:9 to 1:6.5. ...
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Figure 2: Slope design terminology Access to an excavation can be by a road or ramp that may spiral around, or be located on one side of the excavation with switchbacks at each end. A succession of batters between two access ramp sections (or between a ramp section and the floor or crest) is defined as the inter-ramp slope. The inter-ramp slope
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ramp decline system for a shallow deposit. Initial considerations Many factor influence the decision of selecting a shaft or decline/ramp to access an underground mine. Some of these factors include the depth of the deposit, geotechnical aspects, production rate, dimensions, availability of capital, and operating costs.
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Determination of Slope of a Ramp. The slope of a ramp is calculated as the ratio of the height to overcome (h) to the length of the horizontal plane (d), as shown in Figure-1 below. The slope of the ramp is also called as gradient or steepness of the ramp and can be expressed either in ratio or in percentage.
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Optimum ramp design in open pit mines. Mar 01, 2020 · Mining trucks work best when the maximum ramp gradient is between 8% and 10% (Thompson, 2011). Once the design parameters have been defined, engineers must decide whether to use spiral ramps, switchbacks (180 ∘ turns) or a combination of both.
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Ramps (or declines) are often used in underground mines to transport ore, waste, materials, and personnel. This paper studies mine ramp productivity and presents results from a set of computer ...
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The succession of benches between two access ramps is defined as inter-ramp slope. In this image from Kennecott Utah copper mine in Salt Lake Valley, we can clearly identify benches and ramps. The mine is the largest man-made excavation on earth. In this case, ramp spiral around the pit.
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They recommend that the steepest ramp gradient should be 1:8, and above that the walking pace of a pedestrian is slowed down. Independent living. This is a UK website and asks what is the steepest gradient acceptable for a wheelchair ramp. They recognise that the ideal ramps gradient is 1:12, but this cannot always be accommodated.
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ADA specifications cover various aspects, starting with the slope and length of the ramp. A. Ramp Slope. The slope of a wheelchair ramp is a critical factor in ensuring safe and convenient access. ADA code specifies that a wheelchair ramp should have a maximum slope of 1:12. This means that for every inch of vertical rise, there should be …
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Keywords: open pit mine, slope stability, mine reclamation, stripping ratio, production cycle. 1. Introduction. Open pit mining is defined as the method of extracting any near surface ore.
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The problem studied in this paper is that of designing the optimal open pit haulage ramp that, for a given ramp width and a …
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optimising the design of an underground mine decline, so as to minimise the costs associated with infras-tructure development and haulage over the life of the mine. A key …
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This paper focuses on the problem of optimising the design of an underground mine decline, so as to minimise the costs associated with infrastructure development and haulage over the lifetime of the mine. A key design consideration is that the decline must be navigable by trucks and mining equipment, hence must satisfy both gradient and …
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