glass wall

[par060]

sorry if this is a repeat from the structural forum...but it was getting no love...

I am looking for some advise on how to check the capacity of some glass walls. This is laminated insulating glass. the panels consist of 3 panes the outer layers are 1/2" and an inner 1/4" layer with 3/4" spaces between the panes. The panels are 7' wide and 15' tall only supported at the bottom and top edges.

I have looked at ASTM E1300 design charts for 2 edges of support but the lengths they stop at are less than the ones I am looking at. Can I...and if I can how do I extrapolate these tables to meet my criteria. Also any help or explanation on how the 3 lites work together to resist wind forces would be helpful ( do I just add the 3 lite thickness together to check the load resistance)?

 

[Lion06]

I actually just did something EXTREMELY SIMILAR recently. I needed a different chart out of E1300, but my spans were way off the chart.
You can make your own in EXCEL. That's what I did and it worked out very well. You will need to make sure that you use a log scale for both axes. Pick a couple data points that you know for certain off the chart in E1300 and make sure you get the right allowable stress, then..... away you go. Start inputting lengths, calc the moment (this will be the same for all lengths), then back calc the load that gets you to that moment for that span. Use up to whatever lengths you need and include 7 or 8 glass thicknesses on the same chart.

 

[ludvik]

1) Do you have a regular double IGU, or do you have a triple IGU? Regular IGU's are covered by ASTM E1300, though I suppose you could use the spirit of the code and split the load between lites according to their thickness cubed.

2) You can just treat the glass like a simply supported beam, and calculate deflection like you would for steel.

3) You should also keep an eye on deflections with IGU's. Different manufacturers have different deflection limits to hold their warranty on the edge seal. Some fabricators limit you to 1", though you need to check.

4) A 7ft*15ft IGU is huge. Do you have a fabricator that can actually build that?