This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or... more
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or ...
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Abstract Given that an asteroid (or comet) has been determined to contain sufficient material of value to be potentially economic to exploit, a mining method must be selected and implemented. This paper discusses the engineering necessary... more
Abstract Given that an asteroid (or comet) has been determined to contain sufficient material of value to be potentially economic to exploit, a mining method must be selected and implemented. This paper discusses the engineering necessary to bring a mine online, and the opportunities and challenges inherent in asteroid mineral prospects. The very important step of orebody characterization is discussed elsewhere. The mining methods discussed here are based on enclosing the asteroid within a bag in some fashion, whether ...
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Surface Mine Design and Planning for Lunar Regolith Production. [AIP Conference Proceedings 654, 1108 (2003)]. Leslie Sour Gertsch, Richard E. Gertsch. Abstract. Terrestrial surface mine design and planning techniques are ...
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To investigate the differences in the radial drag pick cutting performance in dry and saturated sandstone, a suite of linear rock cutting test was performed using linear rock cutting machine (LRCM). Experimental results of 50 data passes,... more
To investigate the differences in the radial drag pick cutting performance in dry and saturated sandstone, a suite of linear rock cutting test was performed using linear rock cutting machine (LRCM). Experimental results of 50 data passes, incorporating 350 data cuts were used to compute cutting, normal and side forces required for determination of other performance related parameters. Although the forces required to cut the dry and saturated rock were in congruence for most of the spacing and depths of cut combinations; but the overall averaged cutting and normal forces for saturated rock cutting were found to be 9.9% and 9.4% respectively higher than the dry rock cutting. The increase in the overall averaged forces was attributed to strength variability of one of the saturated block affecting the overall forces. The side forces experienced a negligible drop in saturated rock cutting. An increase of 28% and 9% in the actual and nominal specific energy values respectively was also re...
A series of full scale laboratory linear rock cutting tests was carried out with a long bladed single disc cutter (292 mm diameter, 11 mm wide constant cross-section blade) on dry and water saturated sandstone blocks using a linear rock... more
A series of full scale laboratory linear rock cutting tests was carried out with a long bladed single disc cutter (292 mm diameter, 11 mm wide constant cross-section blade) on dry and water saturated sandstone blocks using a linear rock cutting machine (LRCM). The muck collected from the cutting tests has been analyzed to establish a link with the specific energy (SE) of the operation. Coarseness index (CI), a non dimensional parameter, has been found to be a useful indicator of the relative efficiency of the cutting operation. An inverse relationship of the form SE = k CI-n is observed between SE and CI with very high CI usually corresponding with the lowest values of SE. The power n of the relationship for both dry and saturated rock tests is much less than the values found in the previous studies using constant cross section disc cutters and is believed to be dependent on the strength of the rock and the cutter type used. Although the average CI is found to be lower for saturated...
Lunar regolith is known to be surprisingly stiff compared to terrestrial soils because of its angular grain shape, very small grain size, and high relative density. One of the ways to reduce the excavation force and energy is to loosen... more
Lunar regolith is known to be surprisingly stiff compared to terrestrial soils because of its angular grain shape, very small grain size, and high relative density. One of the ways to reduce the excavation force and energy is to loosen the soil prior to excavation. In experiments using JSC-1A ...
Lunar and Martian regolith contain volatile elements within, and on the surfaces of, individual regolith particles. This appears to create potential resources for the manufacture of fuels for spacecraft, including satellites and vehicles... more
Lunar and Martian regolith contain volatile elements within, and on the surfaces of, individual regolith particles. This appears to create potential resources for the manufacture of fuels for spacecraft, including satellites and vehicles on an orbit, transiting between orbits, or even ...
This paper describes a method to deduce in situ soil density from ripping and raking force measurements. A clear understanding of the properties of the substrate including density is required for effective preparation of any site,... more
This paper describes a method to deduce in situ soil density from ripping and raking force measurements. A clear understanding of the properties of the substrate including density is required for effective preparation of any site, whether on Earth, the Moon, or Mars. ...
... Nonetheless, these rigs do not have the wide speed range of dieselelectric rigs and are ... The fluid flows down the drill string and exits the drill bit, typically through specifically sized ... Thesenozzles are often sized to allow... more
... Nonetheless, these rigs do not have the wide speed range of dieselelectric rigs and are ... The fluid flows down the drill string and exits the drill bit, typically through specifically sized ... Thesenozzles are often sized to allow an optimum amount of pressure drop through them to ...
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A permeable quartzose sandstone was subjected to full-scale cutting tests under a chisel-type drag pick, in both dry and fully saturated conditions. Contrary to the results observed from disc cutting tests in the same setup with the same... more
A permeable quartzose sandstone was subjected to full-scale cutting tests under a chisel-type drag pick, in both dry and fully saturated conditions. Contrary to the results observed from disc cutting tests in the same setup with the same rock (Abu Bakar and Gertsch, 2011), saturation actually increased the cutting (drag) and normal (vertical) forces by 9.9% and 9.4%, respectively. The specific energy of cutting also was greater in the saturated samples, by 28%. More expectedly, the relation of fracture surface area to specific energy was ...
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Tunnel boring machines (TBMís) are widely used in tunnel construction in rock. The rock chips (muck) produced are rarely used for construction applications, however, because the suitability of the material is not well understood. Yet the... more
Tunnel boring machines (TBMís) are widely used in tunnel construction in rock. The rock chips (muck) produced are rarely used for construction applications, however, because the suitability of the material is not well understood. Yet the cuttings appear to be of approximately the correct average size for some applications. If they are suitable in other respects, cost savings can be realized in tunnel construction, where aggregate is a common requirement. A review of standard construction aggregate specifications indicates that ...
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Abstract As human activities expand to the Moon, Mars, and other extraterrestrial bodies, it will be necessary to use local resources rather than bringing everything from Earth. In situ resource utilization (ISRU), or planetary surface... more
Abstract As human activities expand to the Moon, Mars, and other extraterrestrial bodies, it will be necessary to use local resources rather than bringing everything from Earth. In situ resource utilization (ISRU), or planetary surface engineering, starts with excavation and dirt-moving. The current study focuses on excavation of lunar regolith simulant by blading with and without preripping (mechanical raking) and points out the need for considering the relative proportion of coarse grains in regolith when dealing with excavation force and ...
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A series of full-scale laboratory disc cutting tests was conducted with a single disc cutter (432mm diameter and a constant cross-section profile) and a single rock type (a coarse-grained red granite). Normal, rolling, and side forces... more
A series of full-scale laboratory disc cutting tests was conducted with a single disc cutter (432mm diameter and a constant cross-section profile) and a single rock type (a coarse-grained red granite). Normal, rolling, and side forces were measured for a series of spacings and penetrations, from which other cutting parameters also were calculated. Although the increases of normal and rolling forces with increased spacing and penetration are as expected, the results illuminate additional aspects of performance prediction. Specific ...
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This is a summary of research work accomplished to date for the Jet Propulsion Laboratory by the Colorado School of Mines and the Michigan Technological University for the Martian Subsurface Explorer (SSX). The task involved a thorough... more
This is a summary of research work accomplished to date for the Jet Propulsion Laboratory by the Colorado School of Mines and the Michigan Technological University for the Martian Subsurface Explorer (SSX). The task involved a thorough review of the state of the art in drilling in the petroleum and mining industries in the following areas: 1) Drilling mechanics and energy requirements. 2) Sidewall friction in boreholes. 3) Rock property characteristics of basalt, permafrost, and ice. 4) Cuttings transport and recompaction of ...
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Abstract: The exploration of space will be easier when local (in situ) resources are used to pro-duce items and consumables that otherwise would have to be shipped up from the deep gravity well of Earth. But nothing has ever been produced... more
Abstract: The exploration of space will be easier when local (in situ) resources are used to pro-duce items and consumables that otherwise would have to be shipped up from the deep gravity well of Earth. But nothing has ever been produced from raw materials collected anywhere other than Earth. Can it be done reliably? How must terrestrial processes be changed to be viable on the Moon, or on Mars? And how much can utilization of in situ resources (ISRU) contribute to the Vision for Space Exploration (VSE) and its potential ...
Introduction: Humans have mined rock and soil for more than 300,000 years [1]. The first mining technology was digging tools shaped from antler, bone, wood, and rock [2],[3]. Today's mines rely on global positioning satellites,... more
Introduction: Humans have mined rock and soil for more than 300,000 years [1]. The first mining technology was digging tools shaped from antler, bone, wood, and rock [2],[3]. Today's mines rely on global positioning satellites, semi-automated machines, and explosives. Lunar and planetary mines will use technology derived from this background and adapted for new environments. All, however, use their technologies for the same purpose: to access the desired material, and separate it from the unwanted material with ...
Given that an asteroid (or comet) has been determined to contain sufficient material of value to be potentially economic to exploit, a mining method must be selected and implemented. This paper discusses the engineering necessary to bring... more
Given that an asteroid (or comet) has been determined to contain sufficient material of value to be potentially economic to exploit, a mining method must be selected and implemented. This paper discusses the engineering necessary to bring a mine online, and the opportunities and challenges inherent in asteroid mineral prospects. The very important step of orebody characterization is discussed elsewhere. The mining methods discussed here are based on enclosing the asteroid within a bag in some fashion, whether ...
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Successful return to the Moon and continuance to Mars requires the sustained ability to use locally available resources at both locations. The hydrogen signal detected by the Lunar Prospector orbiter near both lunar poles [1] could be due... more
Successful return to the Moon and continuance to Mars requires the sustained ability to use locally available resources at both locations. The hydrogen signal detected by the Lunar Prospector orbiter near both lunar poles [1] could be due either to water ice from cometary impacts, ...
Abstract Many" minor" solar-system bodies contain substantial resources that are necessary for developing and maintaining robust human activity in space. Whether asteroids and comets in near-Earth space contain mineable... more
Abstract Many" minor" solar-system bodies contain substantial resources that are necessary for developing and maintaining robust human activity in space. Whether asteroids and comets in near-Earth space contain mineable reserves instead of just mineral resources depends on two factors--economics and technology--that will determine the success or failure of long-term space activity, just as they determine the success or failure of industries on Earth.
... CE Database Search | Descriptions | Search Tips | Subject Heading List. TBM Performance Prediction in Yucca Mountain Welded Tuff From Linear Cutter Tests. by Richard Gertsch , Levent Ozdemir , and Leslie Gertsch pp. 1516-1520 Purchase... more
... CE Database Search | Descriptions | Search Tips | Subject Heading List. TBM Performance Prediction in Yucca Mountain Welded Tuff From Linear Cutter Tests. by Richard Gertsch , Levent Ozdemir , and Leslie Gertsch pp. 1516-1520 Purchase Information Permissions for Reuse ...
Page 1. PTMSS 2006 Abstract Slope stability analysis for application on the Moon Masafumi Iai, Leslie Gertsch, University of Missouri-Rolla ... Slope stability analysis for application on the Moon Masafumi Iai, Leslie Gertsch University... more
Page 1. PTMSS 2006 Abstract Slope stability analysis for application on the Moon Masafumi Iai, Leslie Gertsch, University of Missouri-Rolla ... Slope stability analysis for application on the Moon Masafumi Iai, Leslie Gertsch University of Missouri Rolla PTMSS 2006 Page 3. ...
The key to large-scale blasting in any venue is the efficient distribution of explosive energy in space and time. This requires placing the charges at appropriate depths in a three-dimensional pattern that reflects the properties of the... more
The key to large-scale blasting in any venue is the efficient distribution of explosive energy in space and time. This requires placing the charges at appropriate depths in a three-dimensional pattern that reflects the properties of the material and the degree of fragmentation ...
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Earth has been struck and will be struck again by asteroids and comets whose orbits bring them into close proximity with Earth's orbit, collectively termed Near-Earth Objects (NEOs), and such collisions can be catastrophic. One... more
Earth has been struck and will be struck again by asteroids and comets whose orbits bring them into close proximity with Earth's orbit, collectively termed Near-Earth Objects (NEOs), and such collisions can be catastrophic. One possible means of eliminating the threat posed by a NEO on a collision course with Earth is to deliver and emplace explosive charges into blast holes drilled into the NEO by a human and/or robotic crew.
Asteroid/Comet Classification for Mining Purposes. [ASCE Conference Proceedings 188, 50 (2006)]. Leslie Sour Gertsch, John L. Remo, Richard Gertsch. Abstract. New information about the internal structures of asteroids and comets continues... more
Asteroid/Comet Classification for Mining Purposes. [ASCE Conference Proceedings 188, 50 (2006)]. Leslie Sour Gertsch, John L. Remo, Richard Gertsch. Abstract. New information about the internal structures of asteroids and comets continues to be obtained. ...