6 replies to this topic

[ski89]

So what is the typical procedure for anchoring towers to ledge?

[towertop]

Rock anchors. Drill holes, add epoxy, place anchors. Build form around entire thing. Easy

[ski89]

towertop, on Oct 11 2006, 09:06 AM, said:

Rock anchors. Drill holes, add epoxy, place anchors. Build form around entire thing. Easy

thanks towertop, but...I am looking for more specifics.
I lined up a rock drill and compressor. assuming #8 rod, what size holes? #5 rod, what size holes? type of epoxy? can I mix with a angle drill and paddle mixer? etc.

[ccslider]

Sounds like a question for a certified engineer.

ski89, on Oct 11 2006, 08:53 AM, said:

thanks towertop, but...I am looking for more specifics.
I lined up a rock drill and compressor. assuming #8 rod, what size holes? #5 rod, what size holes? type of epoxy? can I mix with a angle drill and paddle mixer? etc.

[ski89]

Just trying to get prepared. Jumping the gun I guess. The engineer is going with the williams sledge drive rock anchor system. I have been told that they require testing with a porta-power and special attachment. Does anyone know what type of attachment?

[Lift Dinosaur]

ski89, on Oct 17 2006, 04:43 PM, said:

Just trying to get prepared. Jumping the gun I guess. The engineer is going with the williams sledge drive rock anchor system. I have been told that they require testing with a porta-power and special attachment. Does anyone know what type of attachment?

If you are using the Williams Anchor System, they should give you the size of the hole for the size of rod you are using. I believe the standard rod for chairlifts is #8 with a reverse thread "spin lock" nut and a plate. Hole size should be 1 3/4" with 6 feet into the ledge and 2 feet of projection to attach to the foundation rebar/bolt cage. They will also "rent" you an injection system for the resin cartridges and the porta-power/special attachment for pull testing (cost prohibitive to buy one!)
All of this information should be specified by your engineer.

[shoemanII]

check the williams site for general info, but your engineer will (or should) provide you with anchor spec's (type/dia/length), procedure for locking/proof testing the anchor, etc. spin-lock anchors are commonly used. no epoxy is used, spin-locks are a mechanical fastener. lastly, waterproof grout is used to seal the deal.

a critical step in this process is determining if the rock is adequate for anchoring. in vt, the inspector must witness the drilling of these holes, along with the actual anchor install/proof test. if you've ever run a rock drill by hand, seams/voids, etc can be felt.