Is there a structural engineer in the house?

[pdxmonkeyboy]

Hey gang,
I am wondering if there is a structural engineer on the forum that could look over my plans for reinforcing my floor for my impending 600 gallon build. This tank is going over a crawl space that has pier and beam supports perpendicular to the tank length. I have calculated pier footing sizes based on my soils but I have not dealt with pier and beam flooring before so would appreciate some input from someone that can run the numbers.

Thank you!!

 

[Curtis Rose]

Not a structural engineer...but I’m a commercial journeyman carpenter. I’d suggest that u add more than enough. Your whole build will probably weigh close to 6000 pounds. Extra bracing of your joists will be needed. I would go with 4x6 beams opposite direction of joists that carry the joists supported with pier blocks that span a larger space than the tank. Wider footprint will help spread the weight. I deal with pressures from concrete in form work and I would almost always tell u that over building is always better.

 

[jim_fitz]

im a civil engineer from the UK

the thing to consider is not the total gallons but the depth of water
a tall tank excerts more pressure than a shallow one

i have a 3000 litre tank and when people look it they assume ive had lots of structural work done

but their tanks are nearly always as deep as mine mine is 750mm deep BTW

so i ask them what they did to reinforce their floors

more often than not the response is they did nothing


hope that helps

and stay safe over there

 

[pdxmonkeyboy]

Not a structural engineer...but I’m a commercial journeyman carpenter. I’d suggest that u add more than enough. Your whole build will probably weigh close to 6000 pounds. Extra bracing of your joists will be needed. I would go with 4x6 beams opposite direction of joists that carry the joists supported with pier blocks that span a larger space than the tank. Wider footprint will help spread the weight. I deal with pressures from concrete in form work and I would almost always tell u that over building is always better.

I will be adding 4x6 beams opposite to the existing joists. With piers every 4 foot or 8 foot. I understand spreading the load out. What I am trying to determine at this point is whether or not to add additional joists parallel to my existing joists. they are quite a bit apart at this point. This is my first post and beam supported house, but I think they are at least 3' apart.

The beams have 1/2" tongue and groove sub floor and then 3/4 particle board on top of them.

Jim.. in regards to the height, I understand what you are saying but floors are not rated by PSI, they are rated by PSF, and more specifically dynamic loads measured in PSF. My 6,000lb tank will exert 187 pounds per square foot of pressure. Residential floors on this side of the pond are built for live loads of 40-50psf. So I will be 400% over the rated capacity. So in not engineering terms... total failure of my flooring system.

 

[pdxmonkeyboy]

Thought I would follow up. So gave a sketch to the structure engineer in my office.. with a case of beer.. and he said "sooo easy"

So I basically installed pier blocks under each of the 4x6 floor joists and used threaded simpson post bases to tension them.

 

[Kayalvarez]

I will be adding 4x6 beams opposite to the existing joists. With piers every 4 foot or 8 foot. I understand spreading the load out. What I am trying to determine at this point is whether or not to add additional joists parallel to my existing joists. they are quite a bit apart at this point. This is my first post and beam supported house, but I think they are at least 3' apart.

The beams have 1/2" tongue and groove sub floor and then 3/4 particle board on top of them.

Jim.. in regards to the height, I understand what you are saying but floors are not rated by PSI, they are rated by PSF, and more specifically dynamic loads measured in PSF. My 6,000lb tank will exert 187 pounds per square foot of pressure. Residential floors on this side of the pond are built for live loads of 40-50psf. So I will be 400% over the rated capacity. So in not engineering terms... total failure of my flooring system.

Whats the dimensions of the tank