Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: GLB v. Open Webbed Steel Joists

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I have encountered two problems with permitting plans using open web steel
joists in California.  The first problem is with the submittal of the
joists during the permitting process.  Plan checkers will frequently
require the joist manufacturer to sign and seal their erection drawings. 
Vulcraft does not object to signing and sealing their calculations, but
refuse to sign and seal their erection drawings.  The plan checker then
expects me to sign and seal the manufacturer's erection drawings, which I
refuse to do since the joists are not designed by me.  Also, some plan
reviewers have also required that the joist manufacturer submit elevations
of each of their joists, identifying member sizes on each elevation as if
it were a manufactured wood truss.  This is unusual to me since the steel
joists were preapproved and published in the 1994 UBC as acceptable (as
long as SJI monitored the joist manufacturer).  I have used steel joists
elswhere in the country for years without this kind of resistance.  Most
of the plan reviewers act as if open web steel joists are some kind of new
invention that they must regard with suspicion - a very unusual attitude
since steel joists have been around for a very long time.  I also get the
same attitude with regard to the use of steel deck diaphragms.
The second problem I have with steel joists and steel deck diaphragms is
the issue of wall anchorage to concrete or masonry walls.  LA requires
wall anchorage details very similar to that required for wood roofs (i.e.
sidewall subdiaphragms created with the use of steel angle struts
perpendicular to the wall at 4' o.c.).  Others believe that this is
unnecessary.  No testing has been done and I am not aware of any
anectdotal evidence from past performance in earthqakes.  It would be
helpful if their was some consistent policy regarding wall anchorage when
using steel joists and metal deck.

Christopher M. Harris, P.E.