A questions for any structural engineers

new but handy · #1 12-02-2009, 04:12 AM

Quote:

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 · #2 12-02-2009, 04:25 AM

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 · #3 12-02-2009, 04:36 AM

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 · #4 12-02-2009, 04:46 AM

Quote:

Originally Posted by 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

first off ....50 gallons of water is alot more than 50 lbs. 50 gal = ~250L = ~275KG = ~600lbs :-)

the 2x6 wall below the beam is pretty much worthless. If you are interested in beefing up the beam, i would suggest getting an expandable steel column support form RONA or somewhere and putting it inside the wall thats under the beam.

howdy20012002 · #5 12-02-2009, 04:58 AM

sorry I mean 50 gallons.
the 2 x 6 wall is actually a built wall between the furnace room and the bedroom.
there is also one of the original support beams that would fall under where the tanks is as well.
i could look at putting one under the other side as well, if necessary

Fishward · #6 12-02-2009, 05:10 AM

Ya, you're in a much better situation on this one. lots of joists (tank perpendicular to them) a proper structural beam very close and a vertical support column to the foundation if im reading you right. not too much to worry about.

howdy20012002 · #7 12-02-2009, 05:17 AM

glad to hear.
I thought it would be ok.
now for the 3 other systems, those I am going to need to put more support under those..lol
thanks again for taking the time to help me out
Neal

Fishward · #8 12-02-2009, 04:37 AM

Quote:

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.