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Re: Hardy Frame, between code changes

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I saw a similar narrow shear wall type light gauge steel braced frame with a
continuous wood header on top at a website but I forgot what brand it was and
what the website was. It's got truss like diagonals between end vertical
members. I don't know if it has ICBO or L.A. City approval.

There must be other similar products out there. My questions or doubts are:

1. What seismic factor do we use. (Rw=? for braced frame?, for lightgage
tension braced frame?, not specifically in the code so use Engineer's
judgement?) Do we use the seimic factor for this wall line only or for the
whole building or for this direction only?

2. OK, if it's got approval, it passed some kind of test. But how will they
perform in the long run, maybe 5, 10, 20 years from now. (Remember the
continouous threaded rod anchor from foundation to third floor holdown that
got loose?) How was the test conducted?, who conducted the test, what are the
things to consider in determining if the product will meets its purpose, what
is the passing criteria?

3. Do they need special inspection or structural observation to install. Even
if we think they are too simple to install with a clear instructions from the
manufacturer, we are not the ones to install them and you know what those guys
out there are capable of screwing up, especially on a new product.

4. We have to trust the  product's engineer's calculations, assumptions,
loading conditions, member sizes, specifications and connections, etc. Because
if something goes wrong, we cannot just blame the other engineer. we are the
EOR you know. We have to review the product's calcs and drawings very
carefully.

Only after these questions and concerns of mine are answered will I use these
products with total peace of mind. In the meantime, I'll stick with plywood
shear walls, steel columns with fixed base or steel rigid frames or braced
frames.

Ernie Natividad