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Drilled pier cracks

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I was sent some pictures of a concrete drilled pier for a cell phone tower.  The top of one of 3 piers is cracked.  The cracks radiate from the anchor bolt group.  There is a somewhat circular crack that surrounds the bolts and then about 8-12 cracks radiate out to the edge.  It appears the anchor bolts have been pulled up slightly.  I am told the top surface is out of level on this particular pier, with the crown in the middle.


I have a copy of some of the original calculations of the pier.  There are 10-1” dia. Bolts per leg, 78” long.  The note says it is to have a 180 degree bend.  I have never seen an anchor bolt with a 180 degree bend.  Is this common for this type of application?


In order to repair this I think I need to establish the extent of cracking and integrity of the pier.  Is there a reasonable way to establish this?  Is there an ultrasonic type test that can be run?  What kind of results would it tell me?  The pier is 6 ft. in diameter and 41 ft. deep.


Anyone ever run into a repair like this before?  Any suggestions on a fix?  If I could establish that the pier was sound down a certain depth form the top I could request demolishing the bad section and repouring concrete if it wasn’t too deep.  Another solution would be to drill 2 piers adjacent to this one and tie the existing leg into the new piers.  I would assume that taking the tower down is not an option right now.


Thanks for any suggestions.