Bolt Replacement 2

[palk7 EIT]

When an anchor bolt is removed and replaced with new one, how do they take off the existing bolts that are stuck in there (the projection is approx. 1.25 ). There is a location where the bolt is sheared off leaving to 3/4 inch projection. Is that enough for removing and replacing Attached a pic

Thank you

 

[ClearCalcs]

Couple options that come to mind:

-Drill new holes down on your "intact" baseplate flanges and avoid dealing with the existing bolts
-If you can move the base plate, easiest is probably to grind the bolts flush and just move/rotate your plate off 1-2"
-If your baseplate hole clearance allows it (big if), you might be able to core around the bolt and refill with an epoxy anchor.

Hope that helps!

-Laurent

 

[BridgeSmith]

Couple options that come to mind:

-Drill new holes down on your "intact" baseplate flanges and avoid dealing with the existing bolts
-If you can move the base plate, easiest is probably to grind the bolts flush and just move/rotate your plate off 1-2"
-If your baseplate hole clearance allows it (big if), you might be able to core around the bolt and refill with an epoxy anchor.

The first option is unlikely to restore the capacity of the base plate unless all 4 anchor bolts are replaced, so that the base plate is anchored by bolts in perpendicular directions. If the position and orientation of the pole cannot be changed, this may be the only good option using the existing foundation.

The second option is the one we would use on our (DOT) sign structure foundations, if there was a reason we couldn't just replace the foundation.

With the third option, if it can be done, which as you say, is unlikely, it may require larger anchor bolts to meet the max allowed bolt to hole clearance required by the epoxy adhesive manufacturer. Those clearances are typically fairly small.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[HTURKAK]

I would go with new footing..

I am not sure how the bolt is sheared but, probably remaining bolts will also be sheared during dismantling of the pole..

If the footing ( below grade is intact) , remove the pole and severe the anchors and plant new anchors with epoxy .

 

[BridgeSmith]

A word of caution (actually 2): for epoxy anchors the holes must be cleaned thoroughly and the epoxy must be mixed well. After several debacles, we don't use epoxy anchorage for anything in tension, anymore.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[dik]

Reminds me of the 'Big Dig'...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[BridgeSmith]

Reminds me of the 'Big Dig'...

Slightly different situation - there it was the use of the wrong type of epoxy, which didn't have adequate creep resistance.

What I'm talking about is simply a lack of bond between the epoxy and the concrete due to the concrete dust not being cleaned out of the hole, and improper mixing, leading to epoxy that never cures.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[dik]

Yup...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik