Need a book? Engineering books recommendations...

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

RE: Transfer force of large tie beam

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Tie beams are very common and the most cost effective choice once you have exceeded the limit of a hair pin in PEMB's.  It is fairly common to use 4 bars in the tie beam.  Provide a space between the slab on grade and the tie beam itself.  The tie beam is best not to be bonded to the slab on grade.  I would suggest that you use mechanical couplers in lieu of lap splices.  You can place ties at about 18" o.c. just to hold the tie beam bars in place.

I would not worry too much about the stretch of the bar.  Getting 40 grade bars would be more problematic than just using 60 grade bars.  Keep in mind that this is an industry that commonly uses H/40 for a lateral drift limit of the frame. 

Harold Sprague

From: seaint04(--nospam--at)
To: seaint(--nospam--at)
Subject: Transfer force of large tie beam
Date: Sun, 11 Nov 2007 22:00:04 -0600

I have a pre-engineered metal building with some large tie beam forces.  They are around 60 kips.  The reason they are so high is a 40 psf roof snow load with a 13 feet eave height.  The clear span of the rigid frame is 80 feet.  For smaller loads I typically wrap the anchor bolts with a ‘U’ shaped rebar and use mechanical ties for the rebar of the tie beam.  With loads this high I was wondering if I should be using a better mechanism for transferring the forces.  What other options might I consider to transfer the thrust force from the rigid frame to the tie beam?  I’m also wondering about stretching the tie bar itself.  This is a metal frame with metal siding.  What kind of limit should I use as a maximum stretch of the bars?  Should I consider using lower strength steel and a larger area in order to reduce the delta from the PL/AE stretch?






Climb to the top of the charts!  Play Star Shuffle:  the word scramble challenge with star power. Play Now!