Specific impulse, blast waves

The overpressure-consequence relationship in Table 5.3 is given for typical buildings of ordinary construction (i.e., not blast-resistant design). This qualitative characterization of consequences does not explicitly account for the specific structural characteristics of a particular plant building nor does it account for the impulse or duration of the blast wave. As a result, the... 

Because of the importance of the dynamic pressure q in drag or wind effects and target tumbling, it is often reported as a blast wave property. In some instances drag specific impulse i, defined as... 

All flow behind the wave is stopped, and pressures are considerably greater than side-on. The pressure in normally reflected waves is usually designated pr(t), and the peak reflected overpressure, Pr. The integral of overpressure over the positive phase, defined in Equation (13), is the reflected specific impulse ir. Durations of the positive phase of normally reflected waves are almost the same as for side-on waves, thigh explosive blast sources than have most blast parameters. 

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