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vertical clearance to drill post installed anchor

vertical clearance to drill post installed anchor

vertical clearance to drill post installed anchor

(OP)
I have an I beam skid on slab. The I beam already has holes on bottom flange.
Can they drill into concrete if the I beam is just 12" high?
The top flange could be interfering with the drilling tool.

Of course they can remove the I beam skid and drill after they marked the location but can contractor drill with the skid on there?

I don't know all drilling tools out there and the clearance they require.

RE: vertical clearance to drill post installed anchor

I doubt it. Probably best in the future to weld a plate to the bottom of the beam that overhangs the flanges. You could then bolt that down.

RE: vertical clearance to drill post installed anchor

If you don't remove the beam, drill a hle in the top flange, on line with one below for access. Use a sufficiently long masonry drill to drill the concrete.

RE: vertical clearance to drill post installed anchor

Depending on thickness of the flange and edge distances (as well as drill specs), you may be able to drill on a slight angle?

RE: vertical clearance to drill post installed anchor

A couple of other options:

There is a 90 degree elbow that can be installed at the end of hammer drills for angled drilling. Not sure if the length of the drill bit and elbow could fit in a 12" space.

Drill a hole in the top flange to allow for drilling through the bottom flange.

Similar to XR250's idea, weld hold downs to the W12's and install the anchor in the hold downs.

RE: vertical clearance to drill post installed anchor

(OP)
Ok thanks. The i beam is part of a skid that is by the equipment vendor. I'm only doing the foundation. Vendor drawing showed holes on the bottom flange of skid that's why I was asking if I can put post installed anchors there.

RE: vertical clearance to drill post installed anchor

You could cast in adjustable anchors like these:

http://www.decomfg.com/media/deco-heavy-duty-adjus...

They are not inexpensive, but probably cheaper than post-installing an epoxied bolt working through the skid hole or butchering the skid as noted above.

<tangent>
In 1972, I specified 72 such bolts, 4 feet long, embedded in a huge foundation/ inertia mass for two big flight simulators.
The anchors came with RED felt centering washers between the bolt and the sleeve.
The masonry contractor discarded the washers before placing the anchors in plywood templates at finished floor level, 4-1/2 feet above the dirt, to position the bolts.
After the first pour of concrete had hardened around the sleeves, the contractor figured out what the centering washers were for. I got to fly to Mobile and make a bunch of diagonal measurements to figure out if the bolt positions were acceptable, or if he had to demo many yards of concrete.
I figured they were close enough, given big clearance holes in our 'skid bases' and thick washers.
The simulators are still in operation, but I can't get clearance from USCG to look at them.
</tangent>

Mike Halloran
Pembroke Pines, FL, USA

RE: vertical clearance to drill post installed anchor

My sketch is crude, but hw about a clip that sits alongside the flange?

RE: vertical clearance to drill post installed anchor

OG is on the right track. You can use crane rail clips. They are installed just outside the flange, similar to what OG has sketched and they are made to do exactly what you need.

RE: vertical clearance to drill post installed anchor

The crane rail clips I have seen are made for tapered flanges.
There may be some that will work on WFs, but you should check.

Mike Halloran
Pembroke Pines, FL, USA

RE: vertical clearance to drill post installed anchor

A corner reamer will fit but you'll need several different drill bit lengths to do it. I vote for OG's solution if you can live with the clips.

RE: vertical clearance to drill post installed anchor

Why not just take a 5 gal. bucket full of extra drilled holes out to the job site with you, they’re light, and put them wherever you need one? Alternatively, have the vendor send a dozen drilled holes out with the skid, it’s his skid.

RE: vertical clearance to drill post installed anchor

You might investigate right angle attachments for rotary hammers. Here is one for Bosch (but it doesn't have good reviews on the web site) https://www.boschtools.com/ca/en/boschtools-ocs/ha...

I have used a detail similar to Oldestguy except used a flat plate with a shim/plate washer at the anchor. I have seen similar details many times to anchor large air handling units. For seismic anchorage, the plate is typically field welded to the equipment. I have never seen crane rail clips , but they look great if they are readily available in the right size.

RE: vertical clearance to drill post installed anchor

If you had precast bolts you would just fit it onto the precast bolts but still you would have to worry about bending in the weak axis on the web so stiffeners would need to be installed to transfer that force. I honestly don't think it's a good design (no offense to the original designer) but there is a lot of added work that needs to be done to make this work. I think all in all torsion will be introduced onto the bottom beams due to weak axis bending. You could also drill through the top flange with a steel drill bit, then use a concrete drill bit that's what... atleast 23 inches long. I think the drill bit will break over and over again.

So here's what I'd do.
Set Skid in place, paint holes for placement, remove skid, drill the holes, line skid up with holes, clean holes out, use epoxy, insert anchor, wrench it in.

RE: vertical clearance to drill post installed anchor

As to the clip I suggest, all it takes in the shop is a metal cutting saw, power drill, Oxyacetylene torch, bench vise and a hammer. Oh yes, start with bar stock same thickness as the flange if possible.

RE: vertical clearance to drill post installed anchor

Did i miss the option of a pencil and then sliding the skid over 3 inches? :)

The original post mentioned it, i just feel it is way easier than welding clips or casting in AB or trying to over engineer the process. and probably cheaper

RE: vertical clearance to drill post installed anchor

Eric: No welding needed. You heat the bar and bend it. Each one might take all of 10 minutes to make.

RE: vertical clearance to drill post installed anchor

If this in a high seismic area, any connections that rely only on friction won't work

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