SPLIT HAIRPIN???
SPLIT HAIRPIN???
(OP)
PEMB – (Pre-Engineered Metal Building)
12K Horizontal Thrust.
The concrete sub-contractor installed a SPLIT hairpin because they RAN out of rebar!!! I told the general contractor site supervisor that the split hairpin is useless.
Not only THAT – NOW the concrete slab is poured which means I have no access to either the front or sides of the concrete pier in order to post-install anchors for a possible fix for this problem.
THOUGHT #1
HOW do I fix this? “Rip it out and start over!” is my first thought.
Continuous tie-rod(s) from back wall to front wall? We’d have to remove a lot of concrete slab. Too bad!
THOUGHT #2
The foundation is 4’ frost wall.
My thought is: 12K horizontal thrust on top of a concrete pier with (4) #6 vertical rebar doweled to a concrete footing, with four feet vertical of unending horizontal soil behind a 4’ high continuous concrete foundation wall. I realize that I have much to understand regarding soil mechanics and engineering, but, is 12K REALLY going to move this foundation?
Akin to differing opinions from a past thread regarding uplift on PEMB foundations, particularly a small PEMB in Florida, reportedly, with no regard for uplift resistance, is 12K REALLY going to move this foundation?
However, we DO design for the worse case. Rip it out! Start over!
Thoughts? Thank you!
12K Horizontal Thrust.
The concrete sub-contractor installed a SPLIT hairpin because they RAN out of rebar!!! I told the general contractor site supervisor that the split hairpin is useless.
Not only THAT – NOW the concrete slab is poured which means I have no access to either the front or sides of the concrete pier in order to post-install anchors for a possible fix for this problem.
THOUGHT #1
HOW do I fix this? “Rip it out and start over!” is my first thought.
Continuous tie-rod(s) from back wall to front wall? We’d have to remove a lot of concrete slab. Too bad!
THOUGHT #2
The foundation is 4’ frost wall.
My thought is: 12K horizontal thrust on top of a concrete pier with (4) #6 vertical rebar doweled to a concrete footing, with four feet vertical of unending horizontal soil behind a 4’ high continuous concrete foundation wall. I realize that I have much to understand regarding soil mechanics and engineering, but, is 12K REALLY going to move this foundation?
Akin to differing opinions from a past thread regarding uplift on PEMB foundations, particularly a small PEMB in Florida, reportedly, with no regard for uplift resistance, is 12K REALLY going to move this foundation?
However, we DO design for the worse case. Rip it out! Start over!
Thoughts? Thank you!






RE: SPLIT HAIRPIN???
I would say that they need to install it as it should be, hairpins are a little black magic in my eyes but less creepy than nothing
Analyze your wall as a cantilever, can it handle 12k thrust? maybe... probably not
RE: SPLIT HAIRPIN???
RE: SPLIT HAIRPIN???
The pier is 15” perp x 30” parallel to adjacent wall. A cantilevered concrete beam with (6) #6 rebar works great! But, is the soil and adjacent concrete wall an acceptable support for the reaction?
With 2,000 PSF axial soil bearing capacity, this appears MORE than sufficient.
With 2,000 PSF axial capacity, how do I determine horizontal capacity? This is where I lack with soil engineering.
structSU10… I will check into that. Thank you!
RE: SPLIT HAIRPIN???