"Killing" of a nut on an anchor bolt
"Killing" of a nut on an anchor bolt
(OP)
I have 20 or so (out of 7,000) anchor bolts (1" X 13" allthread) set in epoxy grout (17,000 psi avg strength) whose nuts are not fully engaged (about 1 to 2 threads below flush) Rather than bring in the core drillers to pull these out I would like to be able to have a welder come in and "kill" the nut - fill the opening of the nut with a puddle weld The nuts are 2H and they are in a horizontal plane splice connection They are spaced intermittently throughout a run of approximately 1600 feet AWS D1.1 allows the welding repair of anchor studs, but doesn't address this RCSC talks about load and welding with respect to rivets, but not this My PE has provided numbers indicating that there is little load involved (in fact, a jam nut could have been used instead of a full nut) Suggestions? Comments?





RE: "Killing" of a nut on an anchor bolt
Mike Halloran
Pembroke Pines, FL, USA
RE: "Killing" of a nut on an anchor bolt
RE: "Killing" of a nut on an anchor bolt
Second, retighten those connections. Anchor bolts are notorious for loosening up after the first tightening.
Then 'puddle' weld the nuts using E-7018. Have the welder run the rod around the ID of the nut, until a puddle of weld metal [not weldmetal plus slag] fills the nut. Slag will be dripping out of the nut when he finishes.
This is a standard 'fix' for short anchor bolts, but is usually applied to 'soft' Grade 2 nuts. 2H's are readily weldable, but will be 'soft' when done.
RE: "Killing" of a nut on an anchor bolt
RE: "Killing" of a nut on an anchor bolt
RE: "Killing" of a nut on an anchor bolt
AISC specifically states that quenched and tempered anchors should not be welded or heated.
If the EOR will state that there is no shear or tension on the anchors, the argument for plug welding the nuts is purely academic. But, plug welding generally creates a lot of heat. Which would not be recommended within the area of the engaged threads.
Am I missing something?
http://www.FerrellEngineering.com
RE: "Killing" of a nut on an anchor bolt
http://www.FerrellEngineering.com
RE: "Killing" of a nut on an anchor bolt
Here...
http://www.FerrellEngineering.com
RE: "Killing" of a nut on an anchor bolt
RE: "Killing" of a nut on an anchor bolt
Mike Halloran
Pembroke Pines, FL, USA
RE: "Killing" of a nut on an anchor bolt
RE: "Killing" of a nut on an anchor bolt