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UMB Wall Anchors & Fires

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Last night there was a 6 alarm fire in a vacant one story
brick warehouse in San Jose, CA (1st & Julian Sts.)  The
wood roof collapsed and one exterior wall fell outward
injuring two fire fighters.  Luckily they were able to dive
behind a fire truck and the injuries were minor.  The truck
did no fair as well.

The failure was unusual from the news photos I saw in that
the wall failed some what below mid height and the middle
section of the wall ended up in the street.  The building
appeared to have been retrofitted as the were closely spaced
wall anchor plates showing on the portion of the wall left
standing.  Some of the plates ended up pushed outward but
still hanging from the anchor rods.

My concern is that the type of retrofit wall anchor that are
currently being used are capable of inducing some level of
fixity in the wall to framing connection.  When interior
support is lost, as in a fire, this can crank a moment in to
the wall, causing tensile force in the outer wythe of
brick.  Compare this detail with old government or "dog"
anchors: a single pin in the joist loosely held in place
with clinched nails.

In our desire to achieve seismic safety have we missed
something?   Should we be assuring that wall anchors create
a "pinned" condition so as not to induce this type of
failure?  Any comments would be welcomed.

Bob Bossi