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Re: Tilt-up wall Anchorage: 97 UBC

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>The following questions have come up. 
 
1.  Is Fp in equation 32-1 and 32-2 a strength load or service load?  When
we 
do the design of the individual elements do we divide by 1.4 or not? 
 
2. The value of Rp is in question for drilled and epoxied anchors.  We 
typically use 5/8" diameter threaded rods embedded at least 5" into the 
concrete.  We use Hilti HY 150, Simpson SET or Covert type epoxy adhesive. 
In 
UBC section 1632.2, paragraph 3, it indicates that shallow "chemical"
anchors 
are to be designed for an Rp of 1.5.  The last part of the same paragraph 
indicates that Rp for adhesive type connections are to be 1.0.  What is the 
difference between a chemical anchor and a adhesive anchor? < 
 
My understanding is that all seismic loads in the 1997 UBC are strength
level 
loads, so "yes", I would divide Fp by 1.4 for service level loads. 
Regarding 
anchors, the Rp of 1.0 refers to anchorage "by use of adhesive" - I believe 
this does not mean "adhesive anchor bolts" but rather connecting something 
directly using an adhesive applied to the surface.  I would interpret an 
adhesive anchor bolt similarly to a chemical anchor bolt.