Constraints on Modeling of Underground Explosions in Granite.
Abstract
This report summarizes our current understanding of the constraints on modeling of underground explosions in granite. Numerical simulations of explosions in granite are compared with near field waveforms from PILEDRIVER, HARDHAT, and SHOAL, and with peak velocity and peak displacement data from the Hoggar explosions. Numerical simulations agree well with the data at close range. At larger ranges the calculations reproduce the shape of the observed waveforms, but overestimate the observed amplitudes. Dilatancy introduced through the use of an associated flow rule in numerical calculations can make a significant difference in the predicted size of the explosion cavity. The effect is potentially large enough to explain the difference in cavity sizes between the Hoggar explosions and United States granite explosions, however dilatancy also leads to very large near field ground motion, and eliminates overshoot in the explosion source function. Keywords: Rock mechanics; Granite; Underground nuclear explosion; Numerical simulation; Explosion seismology; Dilatancy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1986
- Accession Number
- ADA178288
Entities
People
- J. L. Stevens
- N. Rimer
- S. M. Day