Accession Number:

ADA063934

Title:

The Nuclear Air-Shock Precursor: A Study of the Contribution of Airblast-Generated Seismic Waves.

Descriptive Note:

Master's thesis,

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING

Personal Author(s):

Report Date:

1978-12-01

Pagination or Media Count:

112.0

Abstract:

The coupling into the ground of airblast energy from an atmospheric nuclear burst is postulated as a mechanism which may contribute to if not independently cause the observed airshock precursor. A computer model to test the hypothesis is constructed by assuming an elastic ground medium, applying finite difference techniques to the equations of motion, and using the space- and time-varying overpressure from the nuclear burst to induce the seismic motions within the ground. The surface velocities resulting from simulation of a 28 kiloton atmospheric burst at 500 feet height of burst yielded a dust layer ballistically reaching only 0.64 cm at its highest point for the stiff one-layer ground medium, 0.096 cm for the softer one-layer medium, and a negligible height for the more realisitic four-layer Frenchman Flats medium. Thus, the airblast-induced precursor as postulated ballistic rise only fails to re-create the 2 - 3 meter high dust layers observed in experimental atmospheric nuclear testing. However, the motions are felt to be significant enough to be included in any attempt to model from first principles the precursor and the up-sweep of dust behind the shock front. Author

Subject Categories:

  • Seismology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE