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- To: seaoc(--nospam--at)seaoc.org
- From: jlord(--nospam--at)ruthchek.com
- Date: Tue, 27 Feb 1996 8:05:55 -0800
- >from: jlord(--nospam--at)ruthchek.com
> I have found recently that DSA/SSS and OSHPD do not allow this type >of epoxy attachment system due to a lack of "long-term durability testing".. >We were forced to go to sleeve and/or expansion anchors on recent hospital >jobs because of that "lack" of testing. > I'd be curious if anyone else ran into similar design challenges. > - Terry Weatherby The long term durability issue arises from the use of polyester systems (HILTI, Molly Parabond, Ramset Chemset). Polyester resins react when exposed to alkalies, lime concentrates, & moisture. All three of these may be present in cured concrete. Over time, a process called "saponification" can take place where the matrix breaks down and the integrity of the anchor can be harmed. If you use a true epoxy system, however, this process does not take place. I have never had a problem getting OSHPD to accept products such as Covert and Anchor-It. Bear in mind, however, that these products cost more and are more difficult to use. We require (for large projects) that the company come out and show the workman how to install it. Also, OSHPD does not allow epoxy to be used in permanent tension applications because epoxy softens when heated (& therefore might drop your whatever in a fire.) ...
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