Near Field and Regional Modeling of Explosions at the Degelen Test Site
Abstract
We develop improved dynamic failure models constrained by a large data set of near field waveforms and parametric data from Soviet explosions at the Degelen test site. The Institute for the Dynamics of the Geospheres (IDG) provided digitized data from 23 nuclear tests with yields from 0.3 to 125 KT. The complete data set consists of 77 near field waveforms recorded underground at shot depth and 115 near regional waveforms recorded at 9 stations between 10 and 100 km distance. This data set provides a rare opportunity to observe and model the seismic wavefield as it evolves from the near field to regional distances. We find two distinctly different types of near field waveforms: "narrow-pulse" waveforms suggest that there is little if any strength reduction after failure from this subset of explosions; "wide-pulse" waveforms are more consistent with U.S. experience that material strength is reduced substantially by shock. We implement and test a numerical model of acoustic fluidization in nonlinear explosion simulations. Acoustic fluidization is a possible physical mechanism for strength reduction, and we compare it with other strength reduction mechanisms. Differences in data fit between strength reduction mechanisms are insufficient to uniquely identify which mechanisms are operating.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2006
- Accession Number
- ADA444362
Entities
People
- G. E. Baker
- Haowei Xu
- J. L. Stevens
- N. Rimer
- S. M. Day
Organizations
- Leidos