Accession Number:

ADA066103

Title:

Ground Shock Interactions with Nuclear-Explosion Produced Chimneys.

Descriptive Note:

Topical rept. 15 Nov 76-14 Nov 77,

Corporate Author:

PACIFICA TECHNOLOGY DEL MAR CA

Personal Author(s):

Report Date:

1978-05-20

Pagination or Media Count:

96.0

Abstract:

Results from a series of two-dimensional ground motion calculations are reported. The calculations represent a first cut at understanding both the dynamic and late-time interactions between an underground nuclear test and an existing nuclear explosion-produced chimney. Two general configurations were examined detonations adjacent to a nearby chimney and detonations at the working point of a prior explosion which has produced a chimney. In the adjacent chimney study, two chimney separation distances were investigated for two bounding cases of chimney material strength. The effects of different material strength and chimney shape were studied in the in-chimney computations. Taken together, the computations show the importance of accurately knowing the material response of the chimney material. Material response models used in the computations and the data on which they are based are discussed in detail. All computations for the nearby chimney predict a competent late-time residual hoop stress about the new cavity for the range of properties and separation distances considered. Decreasing the chimney material strength, and to a lesser extent, reducing the separation distance enhanced the influence of the chimney on the magnitude of the dynamic stress field in the region around the new shot point. Reducing the competence of the chimney material in the in-chimney computations dramatically altered both the ground motion and the residual stress field. This sensitivity of the results to the chimney properties suggests that extensive material properties data will be required if a new test is to be conduced, either very near or inside the chimney of an old event. Author

Subject Categories:

  • Soil Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE