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Hi, I am looking for a kind of glass
2

Hi, I am looking for a kind of glass

Hi, I am looking for a kind of glass

(OP)
Hi, I am looking for a kind of glass that has a high transparency (as high as possible to transfer heat) and at the same time I need it to be capable of affording a vehicle load. I have no experience in this field. I just think that as the thickness of the sheet goes bigger, its transparency will go down. Thus, I need something that could be as transparent as possible and could afford vehicle loads at the same time. The dimensions of the glass sheet could be 0.5 * 0.5 m but if it could be wider, that's better.

RE: Hi, I am looking for a kind of glass

Mabrouk92,

Glass loses most energy at its surfaces. If the glass is anti-reflection coated and it is kept clean, your transmissability should be good.

When you say it must afford a vehicle load, do you mean the glass is structural?

--
JHG

RE: Hi, I am looking for a kind of glass

(OP)
drawoh,

Could you clarify what you mean by that the glass is structural? I need the for the glass to be capable of carrying a vehicle load without getting damaged because it will be subjected to traffic and I need a transparent material (as transparent as possible) even if it is not glass but I think that the glass is the most transparent material that I can use.

RE: Hi, I am looking for a kind of glass

Another solar road failure in the making? There's a reason roads aren't made of glass.

RE: Hi, I am looking for a kind of glass

(OP)
No, it is not a solar road. Don't worry :)

RE: Hi, I am looking for a kind of glass

Sorry, but conventional window glass is an insulator, and does not transmit beyond about 2 um, so it does not "transfer heat"

You've used the term "vehicle load" twice, but you've not explained what this means, because it appears you are saying it needs to support the weight of a vehicle. A glass roadway surface would need to be extremely thick and laminated to prevent breakage, which reduces transmission.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Hi, I am looking for a kind of glass

Mabrouk92,
Are you trying to transfer heat through the glass or are you trying to transfer light through the glass to heat something on the underside? If you are trying to transfer heat through the surface, glass is a poor choice for the reasons stated above and likely more, but your insistence on its transparency makes me think you are actually trying to allow light through for solar heating. Is that the case?

Andrew H.
www.mototribology.com

RE: Hi, I am looking for a kind of glass

if the glass or other material will support the traffic load I don't think it will be transparent even for the first day !

RE: Hi, I am looking for a kind of glass

If by "vehicle load" you mean "traffic", glass which is smooth enough to be "transparent" (to light) will be extremely slippery and dangerous.

RE: Hi, I am looking for a kind of glass

Quote (BrianPetersen)

If by "vehicle load" you mean "traffic", glass which is smooth enough to be "transparent" (to light) will be extremely slippery and dangerous.

Easy fix... we have already transitioned to the realm of magical materials that don't exist. Just add "good traction" to the specification requirements:

-Transparent to light
-Transparent to heat
-Supports several tons across a 0.5m span
-Good traction

RE: Hi, I am looking for a kind of glass

(OP)
I am sorry if my post was not clear enough. Yes, I need it to be transparent to light and I will use this light to heat something, and yes it will be subjected to traffic but there is no big fear of the skid resistance so don't count for this.

RE: Hi, I am looking for a kind of glass

More information = better answers.

You need to define your loading conditions, for one thing. "Vehicle" could be anything between a shopping cart and an armored personnel carrier. Perhaps you know where you are going to be on that spectrum, but the rest of us don't.

RE: Hi, I am looking for a kind of glass

(OP)
It will be subjected to regular traffic including Passenger cars, Single unit vehicles, school buses, and small trucks.

RE: Hi, I am looking for a kind of glass

Gooood luck.

If there is regular traffic going across it then you SHOULD be concerned with the friction coefficient. Vehicles lose control and crash into each other when there isn't enough grip, even if there is no hill, even if they are not turning a corner. Happens in winter on icy roads often enough; there's no need to make it happen in summer as well!

What happens when a vehicle drives across it which has a piece of stone embedded in its tire treads? Add to the above selection criteria for this magical material:
- Impact resistant
- Abrasion resistant

RE: Hi, I am looking for a kind of glass

New York used to have glass blocks in some sidewalks, so something similar would be required; but, city traffic is pretty brutal on pavement; so small blocks with multilayer laminations would seem to be the starting point. I don't hold out much hope that you'll get any sort of decent heating; you're looking, at best, getting a couple hundred watt-hours, which seems hardly worth the expense and maintenance of a glass pavement.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Hi, I am looking for a kind of glass

(OP)
Again, the glass will be limited only to a 0.5*0.5m area. Thus it is not a glass pavement. Can we then get a material name??

RE: Hi, I am looking for a kind of glass

Perhaps a safety laminated glass for the stated dimensions. Saflex as a lamination material developed by Monsanto comes to mind. Obviously a lot of tests will be required to determined types of glass such as the tempered type perhaps, thicknesses for the intended loads and light transmission. I have no idea if laminated tempered glass has ever been made.

RE: Hi, I am looking for a kind of glass

A nice coating of dirt will knock back transmissibility and any transferred road tar will finish the job. At 100% in the middle of the day that size is worth about 250W. Factor in losses from dirt and passing vehicles and off-peak values; maybe 50 watts for 40% of daylight hours, trailing off if it's away from tall buildings. After a year or so of surface damage from grit scratched by vehicle tires if it peaks above 10 watts it would be amazing.

Setting up a solar panel in a safe location and running some wires is a better bet.

(There are panels where the outer layers are tempered. The reason for tempering the glass is to prevent surface cracks from penetrating to the core. In lamination this is a natural outcome - surface cracks cannot propagate directly to the inner layers so there's no reason to use tempered glass in center layers. However, for safety, tempered glass prevents shards from injuring people who might have contact with it.)

As far as I know most glasses are terrible for letting IR through. Sapphire is fairly good and is harder than most glasses. I'm not sure if anyone would make it in a piece large enough and thick enough for this case.

RE: Hi, I am looking for a kind of glass

"I will use this light to heat something."

Asphalt gets pretty hot in the sun. Maybe a few heat pipes like the inverse of radiant heating, run thru a larger area area between (or as others mentioned, well above) traffic lanes, could circulate enough coolant to meet your needs.

RE: Hi, I am looking for a kind of glass

handleman,
I suspect that unobtanium is the material Mabrouk92 is proposing to place below this "glass" to act as a heat sink.

Andrew H.
www.mototribology.com

RE: Hi, I am looking for a kind of glass

Make sure to use Unobtanium 42. Accept no substitute.

Proud Member of the Reality-Based Community..

To the Modelmaker, your nice little cartoon drawing looks cool, but your solid model sucks. Do you want me to fix it, or are you going to take all week to get it back to me so I can get some work done?

RE: Hi, I am looking for a kind of glass

Maybe this will work.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Hi, I am looking for a kind of glass

Hey, don't forget cost... Regular ol' aluminum has already been dismissed as "too expensive". α-Al2O3 is out of this world... Unless you can get a piece so transparent that nobody sees you carry it out of the place that is.

RE: Hi, I am looking for a kind of glass

Abrasion alone will kill the clarity in a few hours. Then you can crush the glass into aggregate and put it in the asphalt patch you'll need.

A Great Place For Engineers to Help Engineers

RE: Hi, I am looking for a kind of glass

Just regular tempered and laminated soda lime float glass can take huge structural loads. Its as strong as aluminum. If you use a structural interlayer its basically composite with the other plies. We used it in times square to carry fire truck loads for lighted pavers.

RE: Hi, I am looking for a kind of glass

Macgyver:
Actually i'm remembering these got value engineered out of our project at the last minute (whoops!), but they were designed to be approx 18"*72" and 2.5" thick. They span across the short dimension. From memory the axle load of a fire truck was like 50,000lb. We have done a ton of glass floors though, and even a glass slide 70 stories up. One of the biggest challenges as alluded to above is the scratch resistance, though there are solutions.

RE: Hi, I am looking for a kind of glass



This is a test we did for a project a few years ago. At the base of this image is a piece of glass 3ft * 6ft * 1.25" thick, and each of these bags hanging from the forklift is filled with sandbags, approx 2500lb each. The sandbags used less than 20% of the structural capacity of the glass.

The little hydraulic jack at the bottom applies lateral loads of approx 5000lb.

RE: Hi, I am looking for a kind of glass

I imagine that the picture showing a load test by using a forklift made me think that there are banks and various tellers of small businesses that stay late at nights that uses glass which are bullet resistant for protection. That is a path that may help you.

RE: Hi, I am looking for a kind of glass

Brave guy, no safety glasses on.

Proud Member of the Reality-Based Community..

To the Modelmaker, your nice little cartoon drawing looks cool, but your solid model sucks. Do you want me to fix it, or are you going to take all week to get it back to me so I can get some work done?

RE: Hi, I am looking for a kind of glass

Last month I was standing on the glass floor of the Seattle Space Needle. That glass floor is really really thick.
There are various "skywalks" in Canada, China, probably a bunch more in the USA which would serve as examples of glass structures that must support a considerable load.

www.sparweb.ca

RE: Hi, I am looking for a kind of glass

From OP's profile - "My last login was on Tuesday, September 17, 2019."

RE: Hi, I am looking for a kind of glass

The ASTM for glass floors is actually the best written code I have ever come across, primarily on account of its brevity. ASTM E2751

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