Bending A307 Anchor Bolts
Bending A307 Anchor Bolts
(OP)
Can A307 anchor bolts be bent, without a significant loss of strength? If there is a loss of strength, is it safe to use a portion of the full strength? The contractor installed several anchor bolts crooked (10-15 degrees from vertical). The anchors are 1.25" dia x 12" long cast-in anchors loaded in both tension and shear. If we can't use the anchors, I'm thinking about having the anchors cut off, drill new holes through the base plate, and install epoxy anchors instead (luckily the base plate is large enough to do this).






RE: Bending A307 Anchor Bolts
RE: Bending A307 Anchor Bolts
Are you be worried about failing the concrete while bending? If I'm not able to use the strength of the anchors, I was hoping to still allow them to bend some of them straight, just for erection purposes, so they could set the base plate down on leveling nuts, then grout, then drill and epoxy the new anchors.
RE: Bending A307 Anchor Bolts
I could just be too conservative on this, but it sounds like a bad idea to me. If they drill some new holes or slot the existing holes, they will be able to make a template to located the epoxy anchors and just install them in the right place. Perhaps the holes can be slotted enough to get the column in place and allow new holes and anchors to be drilled. That would require you to size a welded washer to transfer the loads to the base plate since the holes would now be too big.
At some point it comes down to "you're just going to have to pay attention and do it right this time". I don't know why everytime a contractor screws up, it's up to us to fix it. If we screw up, they're on us like flies on...
RE: Bending A307 Anchor Bolts
RE: Bending A307 Anchor Bolts
Make sure you can use multiple washers under the nut. Very recently in my area construction on a large structure came to a halt as it was taking two beveled washers to get the nut bearing area flat. Without the doubling of the washers the nut face was at an angle to base plate and trying to straighten the anchor bolt. The angled anchor bolts were all made and additional anchor bolts were epoxied in. The angle bolts were 1 1/2" dia and 2" dia. Some credit was given for the angled bolts so the additional bolts were smaller due to problems with getting holes in the base plate and concrete.
RE: Bending A307 Anchor Bolts
RE: Bending A307 Anchor Bolts
RE: Bending A307 Anchor Bolts