A questions for any structural engineers

[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]

how wide are the stands? if they are 2' then you are only supporting 250lbs/ft
with the added support you will be fine

[Fishward]

Originally Posted by 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.

The beam at the bottom helps a bunch. I was under the impression this would be point loaded at the feet of the stand. If you can truss the bottom beam into the uprights, that will help keep the load spread out. I would also still suggest putting braces in between the joists immediately below the tanks, to prevent them from buckling sideways.. especially near the retaining wall.

would love to see some pics of the setup when its all together.. sounds like quite the operation.

[howdy20012002]

the stands will be 2 foot wide.
I will also be putting cross members from one truss to the other along the 2 8 foot spans(probably at 2 foot intervals) and along the sides.
that way it can't go anywhere.
unfortunately, I no longer have access to the crawl space.
but I think we did put braces anyways.
I will definitely be posting pics of it when it is up and running and probably as it gets to that point as well.
this will be one of 5 systems I am going to have in my house.

[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.

[new but handy]

sorry for the arguing. I could have just said that I have 3000# sitting on the second floor of my house (6'x2' stand = 250#/ft)I doubled up 1 12' 2x10 in my floor, because the gf was a little scared. to help the 3 joists it sits on. There is 0 movement when I jump next to my tank. (I'm not that small). Stick to your plan you will be fine.
I wouldn't be surprised if a bus was only sitting on 12 sq/ft

[howdy20012002]

thanks again for the input guys..
now for the next one....lol
i have a 230 gallon 7 foot tank that I want to put in another part of my house.
it will be running perpendicular to the 2 x 8 floor joists and pretty much right above the support beam downstairs in the basement (the wall behind the tank is right above the support wall below it)the support beam is 3 - 2 x 8 together.
as well, the support beam has a 2 x 6 wall beneath it from the floor up to the support beam.
i have already had a 180 there with no real problems..and I don't think the extra 50 lbs will make much of a difference
what do u think?
Neal

[Fishward]

Originally Posted by new but handy

sorry for the arguing. I could have just said that I have 3000# sitting on the second floor of my house (6'x2' stand = 250#/ft)I doubled up 1 12' 2x10 in my floor, because the gf was a little scared. to help the 3 joists it sits on. There is 0 movement when I jump next to my tank. (I'm not that small). Stick to your plan you will be fine.
I wouldn't be surprised if a bus was only sitting on 12 sq/ft

not arguing, its a good discussion to have.. i guess this is the difference between what an engineer will tell you (they always tend to be conservative because if you're EVER wrong its your career) and what a handyman will tell you (which will work for most situations). im not at all worried that his tank is gonna collapse through the floor or anything, its deflection and creep over time that will cause the floor to fail.