connecting retrofit PSL col into underside of existing steel lintel 1

[SLTA]

ok smart people. Help me out here.

Clients want to relocate the support between their garage doors to widen one door. I'm proposing the fix as shown in the attached picture. I feel confident on the inside (right side) connections... The trouble is, I cannot for the life of me figure out how to attach the blasted PSL column (3.5x5.25) to the underside of the existing steel angle.

Ron wisely suggested tek screws, and I have looked into that, but to get through the 5/16" thick angle I would be looking at a 3/4" minimum length screw and then I'm about 1/2" into the very fancy Tennessee limestone facade above. I'm pretty sure that would crack the stone, but on the other hand, they did install a light fixture using screws into the stone and they're ok with the result. I've thought about thickening the connection angle instead of using a Simpson angle and welding to the steel, but there's a lot of old, dry wood very nearby and I smell trouble.

So, other screw ideas? Not worry about the tek screws messing up the stone? Weld? Epoxy?

Please remember: we're not all guys!

 

[jayrod12]

I've seen the use of concrete screws (tapcon, Titen HD etc) used successfully in stone provided the contractor takes his time with the drilling.

I would likely be going that route, drill a hole clean through the angle, then install a concrete screw as specified in their installation instructions.

I assume this connection is just for nominal top of column lateral bracing.

 

[mike20793]

Weld clip angles to the bottom of the relief angle and then throughbolt them to the PSL column. Be careful if the PSL is exposed to weather/water. The preservative treated PSL is substantially more expensive and can be difficult to get in certain regions. I usually use a treated glulam if I need preservative treatment.

 

[msquared48]

It looks like you are implying using an angle welded to the bottom of the existing angle?

If so, why not use a kerf plate at the centerline of the new column that is thru bolted to the column and welded to the bottom of the existing angle?

Mike McCann, PE, SE (WA)

 

[KootK]

As long as you get the 3.5 x 5.25 in there snug, do you need to attache it to the angle? It's already tied back to the inner column.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[SLTA]

jayrod, are you saying use the stone to provide the lateral support?

mike20793, I am concerned about the welding. And thanks for the reminder about the PSL - I've confirmed the treated is readily available here, and I'm using a standoff base and wrapping the top.

m^2, I like that idea... but welding.

KootK, I considered that, but there will be old people driving near this and I'd hate to create an issue.

******************

Just got off the phone with the Simpson folks again, and yep, we're going to weld. I'll just make sure the welder is properly certified!

Please remember: we're not all guys!

 

[msquared48]

The welder should be able to protect the 5.25X5.25 column during the welding process.

If the thought bothers you though, use Weldwood!

Mike McCann, PE, SE (WA)

 

[mike20793]

I think the issue of welding near wood is bogus in most cases (I've used it on my wood buildings with zero problems), but fair enough. I agree with Koot, I don't see how attaching to a relief angle gives any more stability than a solid mechanical connection to the inside member.

 

[jayrod12]

I was in essence saying that. I would expect the holes in the angle to be fairly tight therefore both the stone and the steel lintel would provide the lateral support. I can't imagine the demand being that large.

Welding is likely the fastest and easiest option, as long as a certified welder is available.

 

[SLTA]

Part of me totally agrees with you about the outer column extra support. Part of me likes my license way too much. But, the top lateral resistance from the inside ties is significant and the bottom even more so, on both sides, and the two columns are lagged together.

It would also be WAY easier to install without the welding/screwing/etc on the outside beam.

cheers, friends.

Please remember: we're not all guys!

 

[XR250]

I like KootK's idea of doing nothing. No matter what you do, a car will easily knock out these columns if they are so inclined. Actually, you might be better letting the column get knocked out an pray for some unintended composite action rather than the column taking everything along with car ride.

 

[SLTA]

XR250, excellent point. Thanks.

Please remember: we're not all guys!

 

[Ron]

Don't worry about designing a garage door jamb for vehicle impact. Not required nor practical.

Use a Simpson Post Anchor turned upside down on the top of the PSL and secured to the angle with Teks screws. Secure to the PSL with lag screws.

 

[jayrod12]

Ron, you overlooked the issue that in order to use a teks screw that will go through the angle it would be so long that you've got to deal with the limestone stopping it from seating properly.

 

[XR250]

I guess you could pre-drill the hole for the tek screw and then cut off most of the tip and just use it as a self-tapping screw.

 

[Ron]

jayrod....only 3/4" length would be required, maybe 1". Shouldn't be a problem with the limestone. Could also shoot into angle with short studs.