Accession Number : ADP000003

Title :   Shocks in Saturated Sand,


Personal Author(s) : Lempriere,Brian M.

Report Date : SEP 1982

Pagination or Media Count : 14

Abstract : The response of saturated sand to strong shock waves was determined from plate impact experiments and used to predict the environment experienced by a missile capsule buried in a sand-filled shaft under surface blast. Sand samples contained in aluminum or acrylic cups were impacted by aluminum or acrylic discs in a gas gun. Data were obtained for impact and transmitted stress, shock velocity, and relief wave velocity by manganin gauges buried in the sand and on the aluminum or acrylic, and for impact velocity by contact pins. The data were interpreted through numerical models as representing a fluid mixture of quartz and water. They exhibited a small degree of porous crush in the relationship between the pressure dependent loading and unloading velocities, and a small degree of viscosity in shock attenuation at short distances. The numerical models were used in the WONDY computer program to verify their efficacy in representing the experimental data, and in TOODY to analyze waves propagating down a sand shaft in a tuff or a granite host. These calculations showed that oblique shocks were driven into the sand by the plane wave in the host, and under some conditions, led to large pressure excursions on the axis of the shaft. The reflection of oblique shocks was analyzed using an extension of gas dynamics theory to examine these excursions. (Author)

Descriptors :   *Sand, *Shock waves, *Wave propagation, *Impact shock, Guided missiles, Impact tests, Saturation, Numerical methods and procedures, Attenuation, Dynamic response, Stress relaxation, Viscoelasticity, Water, Aluminum, Acrylic resins, Steel

Subject Categories : Geology, Geochemistry and Mineralogy
      Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE