O-166 - Barricade blockage angle distribution

An accidental explosion in an ammunition magazine may result in break-up of the structure and a significant debris hazard. Knowledge about this effect is essential to define safety distances and in order to asses the risk. A well known mitigation method is the application of appropriate barricades.

Various modeling approaches have been developed in order to quantify the debris hazard, such as reported in [AASTP-4, 2008]. An approach that is often taken is to represent each wall of a magazine by a debris point source at the center of the wall. Debris pieces with various masses, launch velocities and launch angles are thrown from the point source, which results in a debris distribution (debris density) in the field.

The effect of a barricade can be taken into account by blocking all debris launch angles below a certain “blockage angle”. This leads to a stepwise transition between distances without debris impact and distances with an undisturbed debris density. In reality the transition will be smoother.

In this short report we present a model for a barricade blockage angle distribution instead of a fixed blockage angle. This will lead to a much more realistic representation of the mitigating effects of a barricade when combined with trajectory calculations. The model can be implemented in all explosion effects software that makes use of point sources.

This report was written as part of MSIAC work element “National Exchange of Information Databases” (DEL-SHR-1) in relation to “Explosion Effects Software”.