Concrete Questions?

[tommu56]

There might be a volume restriction as to the amount of material you have in a single bunker and if you have a "problem" multiple bunkers might save you some product.

At the old Hagley powder works every thing was solid 3 sided with a blow off roof and 1 wall. its an awesome tour if your in the area.

Hagley Museum and Library: Welcome!

tom

 

[jk96]

Just curious but isn't there a limit to the size of magazine? I'd think that a bunch of smaller magazines would be safer than one big one. Maybe not more convenient, but safer.

10,000 lbs of pyrotechnic material per location - shells are figured by 50% of gross weight and multi-shot cake items by 25% of gross weight to get the estimated pyro comp weight. So basically 20,000 lbs total weight for shells or 40,000 lbs total weight for multi-shot cakes per location. Seperation distance is 200 feet between magazines.

 

[crashz]

There is no quick and dirty way to assume this. I'm a civil engineer by education and trade and there is no way that I or any of my collegues would respond with a "rule of thumb" answer to this. I'm not trying to be a jerk here, its just that there are to many unkowns given the information in your posts.

As a building structure, don't you need a building permit? And to obtain the building permit, won't you need sealed plans by an architect or engineer? A single story structure that you describe can easily be designed reasonably by a local engineering firm. Modern structural and concrete design software makes it fairly quick. Probably gonna cost around 5-10% of your total construction cost to do it, and may even save you on overall costs. Would definately remove some laibility off of your shoulders.

 

[dfkrug]

What I'm not sure about is how far I can safely clear span the concrete roof at 8" thick and the amount of rebar required to do it.

I designed this concrete roof last year. It is 8" thick with dual #5s at the
bottom of each "beam", both ways. The foam blocks are there to reduce
weight. I simplified the design to be a bunch of parallel T-shaped beams,
8" wide at the top and 4" wide at the bottom. The span is 20' both ways.
For max strength the bottom bars are 1" from the bottom form. Shoring
was done with 2x4s on end 18" OC both ways.

 

[jk96]

I think I found what I was looking for.

Slab Designer

 

[hitekcountry]

I designed this concrete roof last year. It is 8" thick with dual #5s at the
bottom of each "beam", both ways. The foam blocks are there to reduce
weight. I simplified the design to be a bunch of parallel T-shaped beams,
8" wide at the top and 4" wide at the bottom. The span is 20' both ways.
For max strength the bottom bars are 1" from the bottom form. Shoring
was done with 2x4s on end 18" OC both ways.

Very nice!!!

 

[Egon]

For max strength the bottom bars are 1" from the bottom form.

What coverage does the rebar require to meet your codes?

 

[dfkrug]

What coverage does the rebar require to meet your codes?

As I recall from the ACI 318, you can have as little as 3/4" of cover over
the bars, if the concrete is not exposed to soil, as in the outside wall of
a basement. This is an inside ceiling, so the 3/4" would apply, though
I specced 1", knowing the installers would not be very careful.