Fire Proofing Material Research and Application

This is not my field but to think a bit outside the box...

Most fire rating materials perform by binding water and releasing it when heated. The heat of vaporization cools the product until the water is gone, hopefully two hours.

I wonder if materials designed to adsorb water (silica packs packed with electronic and other packaging) would also release water when heated. I also think that some of the new polymers that absorb 200X their weight in water (Polyacrylimides for example) and used in applications like super adsorbent diapers and environmental clean up booms, are a rout to a new generation of fireproofing.

Thats the answer!! Pack the walls with saturated diapers. It could kill two birds with one stone.

Good luck

Paddler

Hi Paddler,

Well that is thinking, outside of the diaper too! Perhaps housing contractors and engineers may be interested in such breakthrough technology.

I am checking with a company that specializes in calcium silicates, so you're on the right track, hopefully I am.

Thanks for your time!

PS Where in AL are ya'll from? I used to live on an old Army base in Ft. MacClelland, AL back in the late 60's. I heard it's ghandi now though.

Mach1GTX (my favorite cars)

Please visit the following websites for more information on the type of board material or pour material you seek. I encourage you to contact George Swanson who can address any questions you may have and help you to obtain the products.

www.geoswan.com

http://substanceproducts.com/products/catalog/21/sheathing

www.dragonboard.com

Please let him know that I am referring you (Loraine Green) so that he is sure to respond to your inquiry more quickly.

Thanks Loraine, I'll give him a call.

Scott

The purpose of fireproof material used to obtain a fire rating is to slow down the rate at which heat can flow to the steel, thereby keeping the steel temperature below the specified softening point. I used to know what that temperature is, but I've forgotten it long ago.

A fire rating test goes to (I think) 1360C. The protective cover can disintegrate, provided it keeps the steel below the softening point for the specified time, allowing evacuation of the building.

This is why gypsum plaster is good. It's actual temperature resistance isn't great, but the water it evolves cools down the steel and keeps the temperature of the steel at about 100C until the water has gone. At that point the plaster is a crumbled mess, but it has done it's job.

Steel girders in multi story buildings are given a fire rating by spraying on a vermiculite filled concrete which, depending on the thickness can give as much as a 4 hour rating.

Plaster is the cheapest for general household type ratings and use.

Vermiculite faced with fibre cement or plaster sheet is also cheap and can give a good rating. Pearlite can be used in place of vermiculite.

What you use depends on the geometry of your building components and system, as well as the length of fire rating you require.

Hope these ramblings are some help.

Good luck in your search.

Sceptic,

Thanks for your information! We did find the gypsum board very useful for the first fire test. I think in most cases that material or other plaster products would be the best. But due to the way this steel load-bearing wall is designed, we need a material that will withstand higher temperatures. When watching the actual testing in the large furnace, it was impressive to see the reaction in the wall assembly, when the gypsum board side of the assembly was facing the heat vs.the other side without it! It really gave me a feel of what building materials endure in a fire and then how important it is for the structure to remain intact for the time needed (i.e. evacuation as you stated and for firemen to work the fire). I haven't ruled out those materials yet. I wonder if a poured vermiculite plaster product within the wall panel assembly would far better?

Thanks again!

Hi mach1gtx

I wonder if a poured vermiculite plaster product within the wall panel assembly would far better?

Probably, provided you don't mind having the entire sheet collapse when most of the water has been expelled.

If you need it to retain some integrity even if not actually serviceable, then sprayed vermiculite concrete is good. While some water evolution helps with cooling, it's main modus operandi is as an insulator. I think it is good up to about 600C, although the concrete gets crumbly above about 300-400C. (Mainly due to phase change of silica which is accompanied by a significant volume change. I forget the actual transition temperature range, but the structure is damaged both going up and coming down).

Cellulose fibre reinforcement of concrete is surprisingly good. The cellulose retains strength at quite high temperatures (I forget how high) and enables you to get a high volume of fibre into the mix. It can also be used with foamed or vermiculite concrete.

With a little experiment, this approach may give a more damage resistant protection.

If that isn't good enough, then alumino- silicate fibres can be used but they are far more expensive than cellulose. (Glass fibre tends to develop notch sensitivity due to chemical attach from the free lime liberated when cement sets and hardens, so I am dubious of it as a reinforcement in this case)

Finally, it could be worth experimenting with fibre reinforced vermiculite/plaster mix with some cement to help bind it and improve mechanical strength.

Have fun!

Again, I encourage you to investigate the board and pour product that I previously recommended. It is a magnesium oxide based board made of material that has extraordinary performance qualities in terms of strength, durability, the ability to become wet and dry out with no compromise or deterioration to the board, it is mold-proof and exceeds all fire rating tests in the US and internationally. It is the material of choice in all of the tallest sky scrapers being erected in Asia over the past few years. It may be used for virtually all of a building's exterior envelope as well as interior surfaces. It is recyclable and non-toxic and made of sustainably harvested mineral resources. George is currently working with other steel panel manufacturers to optimize their products with success.

Thank you, I will contact him.