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Using non appoved anchors to resist base shear

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jmaddox

Civil/Environmental
Mar 20, 2013
8
I have situation where a contractor used ITW Trubolts to anchor some equipment onto an existing slab. The problem is that Trubolts are not rated to resist seismic loads only "Trubolt +" are. (Which he did not use) No the county wants pull testing done on the anchors.
I have done the calcs and I have ~= 1500# per bolt group and no net tension.

My question is: Can wedge anchors that are not approved (per their ESR report) for seismic loads be used if they are tested? If so, is there a code reference that can be followed? (IBC, or CBC) i.e. percentage of load that the bolt needs to be tested for.
Thanks in advance for any thoughts
 
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I don't think you will find a code reference since the ESR states "Anchors used to resist seismic loads are limited to locations designated Seismic Design Category A and B," and I am assuming that you are in California and have a higher SDC since you are asking for a CBC code reference. However, ASCE 7-05 section 13.4.2 says that the Rp used to calculate the seismic forces shall be less than or equal to 1.5 when the anchors are not prequalified for seismic applications. Be careful, the California Building Code has amended several sections of ASCE 7-05 and ACI 318 Appendix D. California also requires periodic special inspection for post installed anchors (if there was a special inspector, he or she should have noticed that the anchors were not correct). You will probably need to exercise some engineering judgment. The anchor manufacture can probably provide some useful background, but I doubt they will provide a letter stating the anchors are good for your seismic loads.

Expansion anchors are typically torque tested rather than pull tested. It is easier and less costly. OSHPD has a Code Application Notice (CAN) for the 2007 CBC with details on "Field Tests for Post Installed Anchors" ( This provides information on torque testing and loads for tension tests. I think some of this information is included in chapter 19A of the 2010 CBC.
 
Maybe someone can explain this to me...

From what I've seen, seismic rated post-installed anchors are generally rated to maintain tension capacity in cracked concrete. If you're looking at a design case with no uplift, what is your pull test going to tell you? What pull capacity do you test to?

I can see wanting a tension capable anchor in a seismic event, because there are still vertical earthquake forces that we generally don't directly account for, I'm just curious what the criteria for this kind of test would actually be.
 
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