Explosive Stress - h3010v10098

DOE-HDBK-3010-94

4.0 Solids; Summary

Blast effects. Two cases are noted for both detonations and deflagrations.

For detonations in confined areas where immediate dissipation of blast

effects is not anticipated, blast effects may produce larger releases than

shock effects. The largest of the blast and shock numbers is used. A

large blast release is expected for deflagrations of large volumes

(>25% of free confinement volume) of flammable mixtures above

powder with high confinement failure pressure ( > 0.17 MPag [25

psig]). For these cases, an ARF of 1.0 with an RF equal to the

fraction of the original source powder < 10 m is selected.

Accelerated airflow parallel to surface. This condition is representative

of powders shielded from the effects of a detonation or strong

deflagration by standard containers such as a glovebox or can that are

damaged or open. It is noted that small sources of confinement such as

a can should not be in the immediate proximity of a detonation when

using this value.

Bounding

ARF 5E-3/RF 0.3

Venting of Pressurized Powders. This phenomena applies to deflagrations

(i.e., subsonic release of pressure from confinement) as well as pressurization

by other means. Deflagrations involving flammable gases occupying less than

25% of the confinement volume use venting data to estimate ARF and RF

values. Larger volume deflagrations (i.e., >25% of available free volume)

can use these values depending on estimated confinement failure pressure.

For the venting of powders or confinement failure at pressures to

0.17 MPag (~ 25 psig) or less. Large volume deflagrations (> 25%

of confinement volume) where confinement, such as a glovebox, fails at

or less than 0.17 MPag can also use this value for evaluating explosive

phenomena.

Bounding

ARF 5E-3/RF 0.4

For the venting of powders or confinement failure at pressures in the

range of 0.18 to 3.5 MPag (~ 500 psig) or the venting of pressurized

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