Dynamic compaction

Prior studies of dynamic compaction of powders to achieve high density compacts have devoted effort to development of models of localization of mechanical energy on the surfaces of powders to explain observations of local melting. Unfortunately, the models that have been developed are too narrowly focused and do not realistically consider basic materials response aspects of shock-compression processes. The models fail to account for the substantial observations that show results demonstrating that melting is not the universal, dominant process. 

It is particularly significant that no evidence is found for localized melting at particle interfaces in the inorganic materials studied. Apparently, effects commonly observed in dynamic compaction of low shock viscosity metals are not obtained in the less viscous materials of the present study. To successfully predict the occurrence of localized melting, it appears necessary to develop a more realistic physical model of energy localization in shock-compressed powders. 

Efficient Dynamic Compact Models By T. Bechtold, E.B. Rudnyi, and J.G. Korvink... 

Ferreira, A., Meyers, M. A., and Thadani, N. N., Dynamic compaction of titanium aluminides by explosively generated shock waves Microstructure and mechanical properties. Metall. Trans. A, 23A,3251 (1992). 

Wang, L., Wixom, M. R., and Tompson, L. T., Structural and mechanical properties of TiB2 andTiC prepared by self-propagating high-temperature synthesis/dynamic compaction. J. Mater. Sci., 29,534 (1994a). 

Field procedures to decrease the void volume include static and dynamic compaction, pile driving and the use of surface and deep vibratory equipment. Explosives have also been used for this purpose. 

Figure 3.9 Deep dynamic compaction. (Courtesy of Densification, Inc., 40650 Hurley Lane, Paconian Springs, VA, 201290.)...

The ground vibrations caused by dynamic compaction are far greater than those caused by vibroflotation, as shown in Figure 3.10. The proximity of structures subject to vibration damage is an important consideration when deciding on the possible use of this method. 

Lucas, R.G., Geotechnical Engineering Circular No. 1, Dynamic Compaction, 1995, Federal Flighway Administration FHWA-SA-95-037, Washington, DC. 

Leonards, G.A. et al, Dynamic Compaction of Granular Soils, Journal of the Geotechnical Engineering Division, Jan. 1980, pp 35-44, ASCE, Reston, VA. 

Specify equipment for dynamic compaction of a 30-foot-deep medium sand stratum. List all of the assumption you have made. What other... 

A large pocket of loose sand extends from the ground surface to a depth of 42 feet. The site is to be used as a warehouse for machinery parts. The project engineer (you) has ehosen dynamic compaction for soil treatment. Prospective bidders have requested guidelines for acceptable equipment for compaetion and for field testing. In response what do you write ... 

Yamazoe, N., and Miura, N. 1996. Dynamically compacted rechargeable ceramic lithium batteries. Solid State Ionics 86-88, 897-902. 

One of the objective of this research is to fabricate diamond- gradually dispersed cermets by the combination technique of SHS for short time processing and following dynamic compaction for densification. The other is to support for the fabrication by the calculation of residual stress based on graded structure of diamond in the matrix. 

S Kimakhe, S Bohic, C Larrose, A Reynaud, P Pilet, B Giumelli, D Heymann, G Daculsi. Biological activities of sustained polymyxin B release from calcium phosphate biomaterial prepared by dynamic compaction an in vitro study. J Bio-med Mater Res 47 18-27, 1999. 

D. A. Hoke, M. A. Meyers, L. W. Meyer, and G. T. Gray, Reaction synthesis/dynamic compaction of titanium diboride, Metall. Trans. 1992, 23A, 77-78. 

Nashed, R., Thevanayagam, S., Martin, G. R. (2009). Densification and Liquefaction Mitigation of Saturated Silty Soils by Dynamic Compaction - Design. Ground Improvement Journal, Institute of Civil Engineers, UK. 

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