Concrete Break Out
Concrete Break Out
(OP)
I'm wondering how to address the following setup:
I have multiple anchors installed in concrete. The anchors are close enough that the break-out cones overlap. However, the anchors will not be loaded at the same time.
I don't have any set dimensions I'm applying this to, I just need to know how to deal with the general concept.
3 scenarios to consider. First, the unloaded anchor falls completely within the cone of the loaded anchor. Second, the cone of the loaded anchor pass through the unloaded anchor. Third, the unloaded anchor falls outside of the cone of the loaded anchor.
Conservatively I could just apply all spacing reductions to my anchors. But I'm thinking for the first and third scenarios I could just ignore the effect of the unloaded anchor and in the second scenario the unloaded anchor would reinforce the concrete if anything (not that I would count on that). I'm leaning towards just ignoring the effect of the unloaded anchor.
Since only 1 of the 2 anchors are loaded at a time, this is a cylic load. So maybe I should consider the history of the loading and apply all spacing reductions.
Any opinions are appreciated.
I have multiple anchors installed in concrete. The anchors are close enough that the break-out cones overlap. However, the anchors will not be loaded at the same time.
I don't have any set dimensions I'm applying this to, I just need to know how to deal with the general concept.
3 scenarios to consider. First, the unloaded anchor falls completely within the cone of the loaded anchor. Second, the cone of the loaded anchor pass through the unloaded anchor. Third, the unloaded anchor falls outside of the cone of the loaded anchor.
Conservatively I could just apply all spacing reductions to my anchors. But I'm thinking for the first and third scenarios I could just ignore the effect of the unloaded anchor and in the second scenario the unloaded anchor would reinforce the concrete if anything (not that I would count on that). I'm leaning towards just ignoring the effect of the unloaded anchor.
Since only 1 of the 2 anchors are loaded at a time, this is a cylic load. So maybe I should consider the history of the loading and apply all spacing reductions.
Any opinions are appreciated.






RE: Concrete Break Out
Sounds entirely reasonable to exclude the unloaded anchors entirely from the design, those anchors would be loaded under separate load cases with no interacting stresses.
RE: Concrete Break Out
RE: Concrete Break Out
RE: Concrete Break Out
Set up a test section and test your load condition and sequencing...then you'll know.
RE: Concrete Break Out
I would love to set up a test section and see for myself, but I don't think its going to happen this time around. Thanks for the input.
RE: Concrete Break Out
RE: Concrete Break Out
Just make sure that whatever you do is done conservatively.
John Southard, M.S., P.E.
http://www.pdhlibrary.com/
RE: Concrete Break Out
I would say if the anchors have overlaped failure cone they are close enough to work as group. All the anchors in the group shall have the tensile load at the same time.
anchor bolt design crane beam design
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