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- 5Dynamic fragmentation
- 4Ejecta measurements
- 4Particle tracking velocimetry
- 3Brittle materials
- 3In situ testing
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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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Detection of shear zones in a natural clay slope using the cone penetration test and continuous dynamic sampling
Download2000
Mahmoud, M., Woeller, D., Robertson, P. K.
Abstract: The detection of shear zones along which a mass of soil is moving is essential for understanding the state of stability of natural slopes. Weaker zones in clay soils can be identified from low values of cone penetration test (CPT) tip resistance measured during penetration. This paper...
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Dynamic Fragmentation of Natural Ceramic Tiles: Ejecta Measurements and Kinetic Consequences
Download2013
Vincent, Gregory, Rogers, Robert, Spray, John, Schneider, Markus, Hogan, James
Velocity and size measurements of ejecta derived from impacts of railgun-launched projectiles into 10 mm thick gabbro tiles are examined. Fragmentation of the target and the ejecta velocity field are found to be governed by Hertzian fracture and the transfer of kinetic energy to the target. Over...
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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...
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The Effects of Microstructure and Confinement on the Compressive Fragmentation of an Advanced Ceramic
Download2014
Farbaniec, Lukasz, Shaeffer, Matt, Ramesh, K.T., Hogan, James
We investigate the rate-dependent compressive failure and fragmentation of a hot-pressed boron carbide, under both uniaxial and confined biaxial compression, using quantitative fragment analysis coupled with quantitative microstructural analysis. Two distinct fragmentation regimes are observed,...