Explosives Engineering Commons^™

A Review Of Current Safe Distance Calculations And The Risk Of Mild Traumatic Brain Injury, A. R. Loflin, C. E. Johnson

Mining Engineering Faculty Research & Creative Works

Explosive breaching is a tactic operational professionals use to gain rapid entry and tactical advantage. This tactic exposes individuals to repeated low-level blasts (LLB), overpressure exposure generally occurring from user-directed munitions. The experimentation described in this paper highlights the need for further research into implementing explosives in tactical situations, specifically in confined areas, and the effects on individuals exposed. While current safety calculations predict peak pressures from an open-air detonation, this study incorporates the impulse of the total explosive event in a confined space. Sixteen explosive events were conducted to measure peak overpressures of the total duration of the event …

Evaluating Blast Wave Overpressure From Non-Spherical Charges Using Time Of Arrival From High-Speed Video, Kelly Williams, Catherine E. Johnson

Mining Engineering Faculty Research & Creative Works

Scaled distance is used to predict blast wave overpressure surrounding the detonation of a known mass of explosive under the assumption that the charge geometry is spherical. Altering charge geometry from spherical overdrives regions of the blast wave resulting in areas of higher overpressures than predicted by scaled distance calculations. Empirical data can be used to scale the blast wave overpressure to cylindrical charges, but available overpressure data for more complex geometries is not available in published literature. In the present study the time of arrival of the blast wave was measured from high-speed video and the Rankine-Hugoniot relationship used …

Prediction Of Blast-Induced Ground Vibrations: A Comparison Between Empirical And Artificial-Neural-Network Approaches, Luis F. Velasquez

Theses and Dissertations--Mining Engineering

Ground vibrations are a critical factor in the rock blasting process. The instantaneous load application exerted by the gas pressure during the detonation process acts on the blasthole walls creating dynamic stresses in the adjacent rock. This triggers different sorts of stress waves, mainly divided into two categories: body and surface waves. The first comprises the P and the S waves, while the second comprises Rayleigh waves. These waves spread concentrically starting at the blast location and move along the ground surface and its interior, being attenuated as they reach further distances.

In most cases, and accepting the hypothesis that …