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From: John De Armond
Subject: Re: explosives question
Organization: Dixie Communications Public Access.  The Mouth of the South. (John Stephens Cronin) writes:

[not really guns but since it is already started....]

##2) Same question, but for a large building complex (about 4 or 5 city blocks
##of large buildings).
#Definitely going to take a small nuke to do this, no question about it.
#A back pack or tactical artillery nuke ought to be able to do it (ie even
#one kiloton might be enough).

Unfortunately this kind of gross overestimation of the capabilities of
nukes has resulted in the kind of irrational fear commonly seen
in years past.

Structural damage outside the radius of the actual fireball
(which might extend a few dozens of yards for a 1 kt device) is done
primarily by blast overpressure.  Radiant heat does, of course,
cause fires and kills humans but any structural damage is delayed and
best classified as collateral to the main blast.  Some figures for
the destruction of various types of construction:

Frame house							0.5-1 psi
Typical commercial construction		3 psi
Reenforced concrete construction	>5 psi.

From my handy-dandy gen-u-wine government issued atomic bomb blast
computer, a 1 kt device will produce the following overpressure
contours for a surface burst:

	Maximum Dynamic Pressure           radius
	1 psi                              0.24 mile
	3 psi                              0.17 mile
	5 psi                              0.14 mile

This is for flat, unobstructed terrain.  For typical urban terrain,
large structural damage (buildings down) would likely be limited to a block
or two.

A one kt device would make a large bang but it would NOT destroy even a
significant part of a large city.


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