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Skip to Search Results- 7Dynamic fragmentation
- 6Planetary materials
- 6Sand
- 4Brittle fracture
- 3Brittle materials
- 3Ejecta measurements
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2015
Stickle, Angela, Hogan, James, Kimberley, Jamie, Ramesh, K.T.
Modeling of catastrophic disruption requires understanding the processes of dynamic failure and fragmentation. This paper summarizes current mechanisms and models for dynamic failure, strength, and fragmentation, reviewing these from a mechanics perspective and with an emphasis on making links to...
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Debris Field Kinetics during the Dynamic Fragmentation of Polyphase Natural Ceramic Blocks: Ejecta Measurements and Damage Modes
Download2013
Hogan, James, Schneider, Markus, Rogers, Robert, Spray, John, Vincent, Gregory
The dynamic fragmentation of coarse and fine grained granitoid blocks during impact has been examined for energies of 1.9 kJ to 3.0 kJ and 2.7 kJ to 6.8 kJ, respectively. A particle tracking algorithm was developed to measure ejecta size and velocity at the rear of the target for a horizontal...
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2015
Ramesh, K. , Plescia, J.B., Hogan, J.D., Mir, C.E.
Improvements in computational and analytical modelling of large-scale impact and catastrophic disruption events will come from a better understanding of the failure processes that are active during high strain-rate events. In this study we investigate the dynamic compressive failure and...
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Dynamic Fragmentation of Planetary Materials: Length Scale Quantification and Semi-Analytical Modelling
Download2013
Rogers, Robert, Spray, John, Hogan, James
The dynamic fragmentation of planetary materials during impact into finite targets has been examined. A particle tracking algorithm was implemented to estimate the size and velocity of fragments ejected from the rear of the target. A total of 76 experiments were performed for four material,...
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Dynamic Fragmentation of Planetary Materials: Sub-Hypervelocity Ejecta Measurements and Velocity Scaling during Impact Testing
Download2013-01-01
Hogan, James, Vincent, Gregory, Spray, John, Rogers, Robert, Schneider, Markus
Ejecta velocity measurements were made during impacts into solid planetary materials. Ejecta velocity fields overlie each other when normalized by vmax, v50%mass, and v50%KE; these correspond to the maximum velocity and median values of mass and kinetic energy among ejecta velocities....
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2002
Zhang, G., Brachman, R. W. I., Robertson, P. K.
Abstract: An integrated approach to estimate liquefaction-induced ground settlements using CPT data for sites with level ground is presented. The approach combines an existing CPT-based method to estimate liquefaction resistance with laboratory test results on clean sand to evaluate the...
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1995
Abstract: A framework for estimating the ultimate undrained steady state shear strength of sand (S-u) from in situ tests, which combines the theory of critical state soil mechanics with shear wave velocity measurements, is presented. For a particular direction of undrained loading, samples of a...
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1984
Ring shear tests on sand materials have been carried out to show whether there is a change in the behaviour of these materials at high shearing rates and normal stresses. This question is relevant to the problem of the mobility of large rock avalanches (stürzstroms), but is also of more general...
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Impact Failure of Planetary Materials: Lateral Field Ejecta Measurements using Particle Image Velocimetry
Download2014
Schneider, Markus, Spray, John, Rogers, Robert, Hogan, James, Vincent, Gregory
The dynamic fragmentation of a fine grained granitoid material has been examined. Target thicknesses ranged from 7 to 40 mm and impact energies from 12 to 2,500 J. Combined particle image velocimetry and image enhancement techniques are introduced and have been used to measure the size and...
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2000
Czajewski, K., Konrad, J. M., Monahan, P. A., Robertson, P. K., Zavodni, Z., Plewes, H. D., Sokowicz, J., Hofmann, B. A., Cathro, D. C., Law, T., Hughes, J., Howie, J. A., Chan, D. H., Phillips, R., Youd, T. L., Watts, B. D., Morgenstern, N. R., Biggar, K. W., Imrie, A. S., Stewart, R. A., Atukorala, U., Woeller, D. J., Wride, C. E., Scott, D., Piche, R., Kupper, A., Sego, D. C., Gu, W. H., Byrne, P. M., List, B. R., Hammamji, Y., Lord, E. R. F., Campanella, R. G., Finn, W. D. L., Tan, S., Vaid, Y. P.
Abstract: The Canadian geotechnical engineering community has completed a major collaborative 5 year research project entitled the Canadian Liquefaction Experiment (CANLEX). The main objective of the project was to study the phenomenon of soil liquefaction, which can occur in saturated sandy...