Coupling of an overdriven cavity

Conference · Mon Nov 01 04:00:00 EST 1993

OSTI ID:91017

Garbin, H D ^[1]

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1. Sandia National Labs., Albuquerque, NM (United States)

It is well known that when a nuclear test is conducted in a sufficiently large cavity, the resulting seismic signal is sharply reduced when compared to a normal tamped event. Cavity explosions are of interest in the seismic verification community because of this possibility of reducing the seismic energy generated which can lower signal amplitudes and make detection difficult. Reduced amplitudes would also lower seismic yield estimates which has implications in a Threshold Test Ban Treaty (TTBT). In the past several years, there have been a number of nuclear tests at NTS (Nevada Test Site) inside hemispherical cavities. Two such tests were MILL YARD and MISTY ECHO which had instrumentation at the surface and in the free-field. These two tests differ in one important aspect. MILL YARD was completely decoupled i.e., the cavity wall behaved in an elastic manner. It was estimated that MILL YARD`s ground motion was reduced by a factor of at least 70. In contrast, MISTY ECHO was detonated in a hemispherical cavity with the same dimensions as MILL YARD, but with a much larger device yield. This caused an inelastic behavior on the wall and the explosion was not fully decoupled.

• Research Organization: Los Alamos National Lab., NM (United States)
• OSTI ID: 91017
• Report Number(s): LA-UR--93-3839; CONF-930397--; ON: DE95003509
• Country of Publication: United States
• Language: English

Related Subjects

35 ARMS CONTROL
36 MATERIALS SCIENCE
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
CAVITIES
ELASTICITY
NEVADA TEST SITE
NUCLEAR EXPLOSIONS
SEISMIC DETECTION
UNDERGROUND EXPLOSIONS
VERIFICATION