Blast and Fire Propagation in Underground Facilities.

This project investigates the behavior of blast waves from the detonation of explosives and premixed propylene oxideair mixtures in an underground facility. Shots of C4, TNT and propylene oxide predispersed in air were fired at the end of a 20-ft-wide by 6-ft-high tunnel and at the intersection of two tunnels. The effectiveness of detonation of predispersed propylene oxideair mixtures was evaluated in two ways through recording of the pressure of the blast wave and through the effect on targets desks and computers. This report documents the experimental procedures employed and results obtained for three tests in this program the detonation of a 28.8 lb sphere of C4 explosive and two shots involving the detonation of 20 lb of propylene oxide as premixed stoichiometric fuelair mixtures. The three tests were selected in the belief that they would be most useful to researchers attempting to understand and model the effectiveness of explosives detonated in underground facilities. No attempt is made to explain or evaluate the results in this report.