] [Thread] [Date] [Author]

[smthengr(--nospam--at)sirius.com (Jeff Smith)]

>     Dennis , You may already know this but did Simpson tell you that if you
>check for the eccentric bending plus the tension ( minus holes ) of the post
>, that the values in their manuals are way off  reality? When i asked them
>about this they said it is the industry standard to list values as they do. I
>calc about 2600# max for any hd in a 4 x 4  and about 6 kips for any hd in a
>6 x 6  . In plan checking , i have seen engineers use the Simpson tables and
>assume they can get 7460 #  with a hd8a in a 4 x 4 because the table says so
>. Foot note 11 ( and discussion with Bob Greg at SST ) says testing is in
>steel jigs with no wood involved. Many people may not see footnote 4 or know
>to check  UBC sec 2308.1. 

With this approach single HD applications are very rare. For typical three
story buildings with stacked shear walls, it is not unusual to have HD
loads of 10 kips and up. If Simpson is aware of this, then it seems to me
that their catalogue is misleading, even though they have the fine print.
It would be inaccurate to assume that the plywood does not resist some of
the eccentrity. Their HD's values should represent what the intended use of
the hardware is. Full scale shearwall tests would be the best way to
establish values. ( I know..that would cost more money! ) I would
personally like to see Simpson or someone else develop a concentric HD that
would be something like a column base.

Jeff Smith, SE