The Engineer hour (or anyone with sufficient physics knowledge)

[Zylka]

In investigating a new building material - I'm trying to convince through scenario that the lightweight alternative would cut down on material needed for the structural support.

It's regarding a glass canopy that is supported by large steel beams. The comparitive material would weigh roughly 1% of the glass when applied.

Can it therefore be argued that only %1 of the current structural steel (if spaced proportionately) would be required to support the alternative?

[KrazyHorse]

No. Not even close.

[Combat Ingrid]

You need to factor in the amount of steel needed to support the large steel beams

[Zylka]

how much might be sufficient, then? 10%? 15%? 40%?

[Japher]

It's not just a weight issue, but a geometric issue as well.

It's like saying to just take the material off the bottom

[Last Conformist]

1% the weight of glass? You better watch before that stuff flies away.

And no, you won't be able to reduce the amount of steel with anything like 99%.

[Japher]

Who put Zylka in charge of building a building? Which one is it?

Just so I never go in it...q

[KrazyHorse]

Originally posted by Combat Ingrid
You need to factor in the amount of steel needed to support the large steel beams

Not quite. That scales appropriately. The problem is one of rigidity, and of external forces (other than simple gravity)

A large canopy catches the wind. People might walk into the supports. If the material doesn't have enough rigidity to support itself then you need additional columns.

Zylka, what sort of sizes are we talking about here? How tall is this? How big is the canopy? Is this indoors or outdoors?

I'm not an engineer, but these are all factors which will have a huge impact on the relative savings.

[Zylka]

what I'm saying is, the load it supports is a fairly illongated canopy that would not change in dimension, only decrease to %1 weight. Regardless of how the engineer wanted to proportion or re-number a new series of support beams - with what (approximate) amount of material might he/she be able to bare the new load?

[KrazyHorse]

Answer my questions and I'll give you a number which won't be completely ridiculous (but which also won't be anything other than a guess)

[Zylka]

It's outdoors.. like a city block long, maybe 15-20 feet high, running parallel about the block. A train platform

and yeah, thus far a lot of pertinent points have been brought up that I hadn't thought of, ie.) wind

[Zylka]

for an aproximate size of canopy - I'd say just over 1600 square feet.

The alternative material itself is very rigid and self supporting.

[KrazyHorse]

Holy ****. That bad boy is going to get ripped to shreds. No way you can get away with any significant savings whatsoever. 95% of the steel that would need to be in place to support the glass isn't there to support the weight, but to just keep it anchored.

There will be virtually no savings whatsoever on the support structure. I'm also pretty sure that the saran wrap you're planning to put up will get destroyed with the first real breeze.

[Zylka]

%95 of the support is anchoring??? HAHAHAHA well down the toilet goes this scenario design. Ah well

You're sure, though? The glass panes are *ing huge. Like up to 250lbs per pane. The structural support is also figured to suffice for a winter load of "3 feet of wet snow"

Regarding wind, I guess I should mention that the 1600ft canopy is broken up into two sections, roughly a third and two thirds respectively. So one 1000ft canopy, one 600ft

[Combat Ingrid]

Originally posted by KrazyHorse
Holy ****. That bad boy is going to get ripped to shreds. No way you can get away with any significant savings whatsoever. 95% of the steel that would need to be in place to support the glass isn't there to support the weight, but to just keep it anchored.

There will be virtually no savings whatsoever on the support structure. I'm also pretty sure that the saran wrap you're planning to put up will get destroyed with the first real breeze.

So I guess we can agree now that he will need to keep the steel to support the steel support?