Need a book? Engineering books recommendations...

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

RE: Simpson's SET Epoxy Anchor vs. Titen HD Anchor

[Subject Prev][Subject Next][Thread Prev][Thread Next]

Hilti (and I assume Simpson) indicates a minimum edge distance from the face of a concrete slab or stem wall to the centerline of the anchor. Generally this is 2.75” for 2x6 plate which would give a 5-1/2” diameter cone assumed at the surface of the concrete. In most cases a wedge or expansion anchor can take the chance and blow out the side of the concrete. I am not aware of Titen anchors, but here are the guidelines I would use:

  1. Use an epoxy anchor for shear bolts and argue the need for deputy inspection when uplift is not a consideration, the purpose of a shear bolt is to keep the bolt working parallel to the surface of the concrete until the weakest material fails which will most likely be the wood plate.
  2. If you need tension, the latest Simpson SET catalog allows for greater tension capacity (limited by the strength of the A307 bolt and increase the capacity for pull-out based on the diameter and depth of the anchor into the existing foundation. A cone may be used to evaluate the capacity, but the chance of blow-out is greatly reduced. Deputy inspection will be required, but in my opinion, its worth the few hundred dollars.
  3. If you need greater capacity then you may want to resort to undermining the existing foundation when dealing with a slab on grade and design a dead man foundation below that you can embed a threaded rod with plate washer and two nuts on each end. One thing to keep in mind is that you don’t have to over drill the hole if you are installing a dead man foundation, but you do oversize the hole by 1/8” to allow for epoxy embedded into the existing slab edge or foundation wall. In this case, you should use the Simpson BP plate with the four SDS screws to compensate for a larger whole. The Epoxy fills the hole, but there is no assurance that he epoxy will fill the enlarged hole in the wood which can cause a dynamic force against the inside face of the wood hole parallel to grain. The screwed plate washer will help distribute the anchor force into the screwed connection through the top of the plate. This is not as critical if you are using the epoxy anchor for tension only.
  4. I am also not a fan of HPAHD strap Holddowns – especially in my area where the installation generally spalls the concrete on most of them as the builder saves a few bucks by not using forms to tie the straps in place. The problem in areas such as mine is that the soil is highly mineralized and the strap will corrode through within two years losing all resistance to uplift. I’ve come back in to epoxy coat the exposed metals but I will not use strap Holddowns in my area (the reason that I lose a lot of work to those who will give the builder what he wants. (Sorry, I’m being egotistical).

Rather than discuss this with the Simpson Rep, call Simpson’s Technical support or ask for their R&D department in Oakland and ask for Karen Colonies (sorry about the spelling). She has been tracking these problems back a few years (if she is even still with Simpson which she probably is). You can also contact Steve Pryor at the Dublin Office who is an SE and who is also very well informed on the testing and problems they face with some of their epoxy and strap connections.  In my experience, not to speak badly of the Rep’s, but I consider them more as sales people to help with customer care in the field and while some may be professional engineers, I find that they are limited to the amount knowledge hey have when it comes time to testing in research and development of products.

 

Best Regards,

Dennis


From: Robert Kazanjy [mailto:rkazanjy(--nospam--at)gmail.com]
Sent: Saturday, July 29, 2006 11:31 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: Simpsons SET Epoxy Anchor vs Titen HD Anchor

 

 

On 7/29/06, Brian <bsh117(--nospam--at)yahoo.com> wrote:

Thanks Jim,

I will contact my Simpson's rep again and ask him that
question.  When I contacted them the first time, they
really weren't that much help.  All the rep could do
is reiterate the exact same information that was shown
in their load catalog.

I could be mistaken, but I was under the impression
that expansion anchors were not recommended in seismic
conditions.  Is that correct?  If so, where could I
find that information?  I was wondering if this same
condition might hold true for the Titen HD anchors.

Thanks!
Brian

--- Jim Getaz <jgetaz(--nospam--at)shockeyprecast.com> wrote:

>             Brian,
>
>                         The last time I looked at
> Simpson's Titen bolts,
> Simpson said they were not to be used for more than
> about 30 days
> outdoors. I have called for Powers Wedge-Bolts
> outdoors.
>
>             Jim Getaz
>
>


Brian-



The Simpson website has tons of tech info but you have to drill down a little bit to get to it.

http://www.simpsonanchors.com/catalog/mechanical/titen-hd/index.html#perform

http://www.simpsonanchors.com/pdf/fliers/F-SAS-THD06.pdf

here's the link to the ICC ES Report
http://www.simpsonanchors.com/pdf/codes/esr1056.pdf

the COLA Report is a letter & the ICC ES Report with some mods to it.

Based a  cursory read of the ICC report the only restrictions for the Titen HD are:  corrosive or outdoor enviroment use & fire resistive conditions.....IMO looks seismic is OK even tension (allowable loads are low)

The Simpson wedge anchor is ok for seismic (shear & tension) even though I prefer chemical anchors for seismic tension loads

http://www.simpsonanchors.com/catalog/mechanical/wedge-all/loads_carbonsteeltension.html
(Table Note 2)


cheers
Boib