Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
(OP)
Hi
Does anyone have any recommendations as to how to prevent side-face blowout of an anchor bolt near a free edge? I cannot increase the pier size as I am stuck with arch requirements nor can I reduce the bolt length. Can I add stirrups @ 3'' spacing and call it good? Can the stirrups even help in preventing side face blowout? ACI code does not mention anything about reinforcement for side-face blowout. How do I prevent this?
Thanks
Does anyone have any recommendations as to how to prevent side-face blowout of an anchor bolt near a free edge? I cannot increase the pier size as I am stuck with arch requirements nor can I reduce the bolt length. Can I add stirrups @ 3'' spacing and call it good? Can the stirrups even help in preventing side face blowout? ACI code does not mention anything about reinforcement for side-face blowout. How do I prevent this?
Thanks






RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
A lot of engineers do ignore side face blowout when they detail the anchorage and rebar to develop Fy. As long as all other limit states are precluded, I don't have much concern over sideface blowout most of the time.
Also, what about switching to non-headed anchors?
"It is imperative Cunth doesn't get his hands on those codes."
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Are you looking at side face blowout due to anchors in tension? If so, KootK has a document that deals with edge distance, reinforcing, and blowout.
(Upon carefully reading your title, I see that anchors in tension is indeed the case)
Hopefully he will stumble across this thread.
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
BAGW - 1000 kips of tension?? I think that falls outside of typical conditions. Read the PDF in the thread link I provided. If you feel it is needed, you can use a strut and tie model to restrain the blow out spall.
Why not mechanical couple instead of using headed anchors?
"It is imperative Cunth doesn't get his hands on those codes."
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Thread with detail
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Mike McCann, PE, SE (WA)
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
"It is imperative Cunth doesn't get his hands on those codes."
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Side-face blowout is a localized fail of the concrete in crushing, projecting from the head towards the near face. I would say that we are likely never going to get design criteria allowing full tension transfer to reinforcement. It is possible with additional testing we may get an increase to the loads, I doubt it will be what people want it to be.
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
Is your tension the result of net uplift or moment at the base? If it is from moment at the base, you might consider treating the pedestal as if it were an exterior roof level beam-column joint and detail the transverse reinforcing to satisfy ACI 352R. Testing has shown that Appendix D is overly conservative when used to calculate the capacity of headed bars in this condition, likely for two reasons: (1) the joint is well-confined with transverse reinforcing, (2) the head is anchored within the diagonal compression strut.
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?
RE: Anchor side-face blowout in tension. Ways to prevent it without increasing the edge distance?