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Re: Super Typhoon Paka

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Well here is my two cents;

This was my first major typhoon and it was an experience.  After going
through any number of earthquakes in California including Loma Prieta, this
was an amazing event to watch, the most amazing part being that you get to
spend eight hours watching the damage occur.

My office has looked at a number of damaged structures ranging from homes to
power poles, and the damage is quite extensive.  

>From the residential side, as Eric stated, the majority of the damage was to
wood and tin houses.  These homes look as bad as any trailer parks I have
seen on CNN following a tornado.  The extent of the damage and the quality
of the structures really makes one long for the conventional framing
standards in the UBC.  Most of these structures are (were) constructed by
the owners and I'm sure almost none were permitted.  (And you thought you
were fighting battles in California!)

I would also add that there were some wood and tin structures that did fine.
Two wood and tin canopy's near my house had no damage.  These appear to have
been  constructed properly, with sufficient nailing of the tin and wood
members.  Another example was a wood lattice I saw recently constructed
using hurricane clips.  This also came through with no apparent damage.

As far as concrete buildings, the only real damage we have seen was to an
older concrete home with a thin (5") roof slab.  This house is located at
the top of a ridge with direct exposure to the ocean.  A portion of the roof
overhang was flipped up onto the main roof.  The overhang is approximately 3
1/2' long.  There was no bottom steel in the cantilever and the concrete
failed along the line of the supporting wall.

We have also inspected some power poles.  The failures of the wood poles is
quite obvious (with the aid of termites in some cases) but the failure of
the spun concrete poles may have taken some by surprise.  The poles are
prestressed with smooth wire and the wall are fairly thin, around 3".  The
majority of the failures appear to be from crushing of the concrete at the
base of the poles.

The most dramatic and impressive failures we have seen has been at a port
project.   The port was designed as a concrete deck supported by concrete
piles.  The piles are 2 foot square prestressed piles.  The project is in
the main harbor of Guam, fairly isolated from the main ocean swells.
However the force of the water at this location sheared six of these piles
off at the mudline!!

As I stated this was quite a storm to experience.  After designing concrete
buildings in California for seven years, the eight hours I sat in my house
and watched the winds blow, certainly reminded me of the force winds can
impose on a structure.

If anyone is interested, we should have some photos on our web site in the
next week or so,

John F. Jones
Winzler & Kelly Consulting Engineers
Agana, Guam