A questions for any structural engineers

[sphelps]

I should note at this point that my advice is only relative to the steel structure holding the two tanks. I can't comment too much on the floor holding that much weight as there are way too many variables to consider. I assumed this was on a solid floor, you'll definitely need something above normal floor conditions to support the weight on a raised floor.

[Fishward]

Originally Posted by sphelps

I should note at this point that my advice is only relative to the steel structure holding the two tanks. I can't comment too much on the floor holding that much weight as there are way too many variables to consider. I assumed this was on a solid floor, you'll definitely need something above normal floor conditions to support the weight on a raised floor.

Im going to go ahead and qualify all this advice as well as i've not seen your actual flooring. I really dont need to get sued after the floor collapses and causes 20K in damage. My recommendation stands though that you seriously consider the strength of your floor before you put that kind of load on it.

Something to consider: general design parameter for living space is 40lbs/sqf. the are under this tank will be facing loading about 10 times that.

[howdy20012002]

Hello all
first of all - No one worry about getting sued..i don't think I would have much of a chance of sueing someone for some free advice I got from an online forum. and even if I could, I wouldn't. So no worries there.
i do appreciate your inputs.
just to clarify about the structure of the house.
the room is 12 feet across.
beneath this is a crawl space.
the 2 x 10's are actually resting on the perpendicular 2 foot retaining wall at the 6 foot mark or halfway mark, which has the 2 - 12 inch by 12 feet deep pilings.
I am not sure if this was clear.
I don't really see how, being that it is actually resting on the retaining wall in the middle of the room, that there could be any movement at all really.
or am I right out of it?
the concrete wall is 10 inch thick reinforced by lots of rebar.
let me know what u think

[new but handy]

You should be fine with the joists but I would worry about where the feet of the stand are. (ie. between the joists.)

[Norseman]

aluminium doesn't rust. come in aircraft grades and is light weight easy to weld and looks nice and takes powdercoat well. just a thought.

[Fishward]

[/quote]
I don't really see how, being that it is actually resting on the retaining wall in the middle of the room, that there could be any movement at all really.
[/quote]

I trust the retaining wall, what i dont trust is 2 2x10s at a 6 ft span holding up 3000lbs.

http://www.awc.org/calculators/span/...rcalcstyle.asp

at 100 psf (pounds per square foor) this calc says your max span is 10ft. you've got 4 times that....

[new but handy]

doesn't that chart say 100 at 11'6? so double that because of the 6' span. and consider that according to the BCBC (British Columbia Building Code) 12kPa or 250lbs/foot is the required strength for loaded bus or all truck parking over living spaces. You should be ok

[Fishward]

Originally Posted by new but handy

doesn't that chart say 100 at 11'6? so double that because of the 6' span. and consider that according to the BCBC (British Columbia Building Code) 12kPa or 250lbs/foot is the required strength for loaded bus or all truck parking over living spaces. You should be ok

You should switch the chart to only allow for deflection of L/720. rigidity is important for loaded glass boxes... that will give you a different span

"250lbs/foot is the required strength for loaded bus or all truck parking over living spaces" - my point exactly.. he's got loading of over 400lbs/ft. would you park a fully loaded bus or truck on 2 2x10s?

[howdy20012002]

but the 2 x 10 have no where to go....they are completely supported by the retaining wall below them...they would basically have to be crushed for them to go anywhere or the retaining wall would have to be pushed down.
as well the the retaining wall will be dead centre of where the tank is going to be above it. so the tank will be stradling the wall.
as for the stand ends, I woudl be running a 3 x 3 beam along the bottom of the stand along the floor. that way the weight will be dispersed along the entire length.

[new but handy]

Originally Posted by Fishward

You should switch the chart to only allow for deflection of L/720. rigidity is important for loaded glass boxes... that will give you a different span

"250lbs/foot is the required strength for loaded bus or all truck parking over living spaces" - my point exactly.. he's got loading of over 400lbs/ft. would you park a fully loaded bus or truck on 2 2x10s?

Not a bus but I would have no problems driving my 6000# truck across 2 6' 2x10's. I put 2 2500# lifts of lumber on 10' spans all the time.