[Radix] Triangle of Life

[David Alexander]

Every time there is a major earthquake leading to mass entrapment  
Douglas Copp's 'triangle of life' is discussed.

It is true that multiple-storey reinforced concrete buildings that  
totally collapse may have up to 15 per cent void space and that is  
likely to be found next to substantial solid elements that arrest the  
fall of columns, beams and floors. The first problem is that much  
depends on the production of dust and small debris, which can fill the  
voids. That was the case more or less universally in the 6 April 2009  
L'Aquila (Italy) earthquake (308 dead, 1500 injured), in which there  
was no indication that the triangle of life had any relevance at all.  
Secondly, the size of the void space depends on the whether the  
falling elements fragment as they collapse or not. They may. The  
result may be crushing of the hapless victim.

But what should a person in a building do during a major earthquake?  
There is no hard and fast answer, because it depends on the local  
circumstances. Statistically it is better to remain indoors than rush  
outside, as facade collapse, and other forms of partial collapse, are  
more likely than total collapse, and stairwells may be particularly  
susceptible. Anyway, it may be physically impossible to exit the  
building.

I think it is more or less impossible to protect oneself against total  
collapse, but it would be possible to evolve a simple, robust  
methodology to identify the safest part of a building that suffers  
partial damage, which occupants could retreat to. That is my strategy  
for my own home (I live in a seismic area) and I am trying to codify  
it as a simple, useable methodology.

David
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David Alexander
CESPRO - Università di Firenze
protezione-civile-italia.blogspot.com
emergency-planning.blogspot.com
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