Glass Window Wall with Glass Girts?

[XR250]

Saw this at an Aloft hotel I recently stayed in NYC.
Looks like they are using structural glass wind beams to brace the wall.
The beams appear to have moment connections at the steel attachment brackets as they are spliced at that location.
Never seen such a thing.

 

[JAE]

Probably something like a Pilkington system:

http://www.pilkington.com/en/us/products/product-categories/glass-systems

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[XR250]

Kinda looks that way. Thanks.

 

[KootK]

It's a curious thing. Per the latest Aluminum Design Manual, you can no longer use glass to LTB brace aluminum mullions. But then you can use glass to brace glass mullions? Facade engineering is cowboy country for sure.

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.

 

[klaus.]

Well looks like a standard glass wall construction....nothing special
When working with glass one have to leave the 'codes' sometimes..... especially in USA where there is no real code for glass constructions

 

[dik]

I didn't know that you couldn't use the glazing for lateral support... don't know why... it's done when glazing is used for lateral support of other glazing and is used in the automotive industry when the windscreen is polyurethaned in place to add to the body strength.

There was an office building in Toronto that used glazing vertical supports that I first saw about 20 or 30 years ago; I don't recall, but the glazing height could have been 15' or 20' and I recall being surprised at the use of glazing for this purpose.

Dik

Dik

 

[MotorCity]

There are a few of these systems around my neck of the woods. I suspect that glass glazing is bracing the glass fins, whether its allowed by code or not. Not sure what would brace the inside of the fin when it goes into compression under a wall suction load.

 

[jike]

I have seen something similar before, perhaps 10 years ago, at the glass atrium leading into a football stadium.

 

[NorthCivil]

This is why I love glass engineering.

The bulk of this design can be checked with codes. ASTM E1300, and Australian standard AS 1288.

There is ASTM C1048 which offers some guidance on how to specify the holes in the glass at the splices. Along with some first principles, and a generous self determined factor of safety, this part is too difficult.

a little bit of licking your thumb and holding it up to the wind as well of course.

Never seen that type of dedicated moment connection at the ends of the glass beams though. interesting work.

Glass engineering is a bit of the wild west at the moment. But without the cowboys, the west cannot be won

 

[XR250]

I would hope a significant amount of testing was done on these assemblies before production.
I can't imagine strict analysis would be enough

 

[klaus.]

well answer is easy...since there is NO Code that allows or forbids this
This is pure engineering at the state of art for glass constructions...
Interesting field to work in..

there are many of these glass wall types around the world
like this one in the center of NY
Link

 

[NorthCivil]

XR250

I doubt testing was done. Though the design of this thing is unguided, it's not totally unique. I've designed a fair few similar glazed walls, and never tested any. For sure had the first couple ones I designed concept reviewed by qualified individuals. I'm sure if I asked for testing I would have been let go.

There is actually quite a lot of redundancy in this system. More than you get with your typical conventional sealed units glazed in frame, which is all over the place and no longer picture worthy.

 

[XR250]

I doubt testing was done.

NC,
Seems to most difficult part of this design is the LTB of the glass fin.
How would you handle that?

 

[klaus.]

Well nowadays no problem using a general FE Program
I know there are several papers and Thesis done on that question...

 

[XR250]

I'm still not convinced building something this cutting edge (no pun intended) should go without testing.
Sheesh, even the slide clips used at the top of metal stud walls are tested even though they could easily be designed using FEA or maybe even hand calcs.

 

[klaus.]

usually testing need to be done for the post breakage behaviour which cannot be simulated in the computer

 

[MrHershey]

Hawaii Convention Center in Honolulu uses something similar.

 

[KootK]

I believe that the Aussie glass standard that NorthCivil mentioned contains some provisions for LTB. Whether or not they have been validated by testing, I couldn't say.

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.