I agree you can't have too many sheds. We are going to have 2 built this year, an 18 x 18 ft for 2 years of firewood storage and another for implements and a trailer.
the challenge....
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I can put up a pole building and repair sunken posts, but I don't know that I have the requisite skills to pour the needed pad for weight distribution even in small sections-given the need for rebar and our frost line depth-at least 3'. It needs to be able to withstand at least 10K lbs weight (likely more). My 2.5 ft^3 cement mixer would stress out. I think this is likely a job I need to keep saving for if I want it done correctly. The pad will be for 30 x 50' area in the middle of the barn. The side bays of the barn will be gravel.
I appreciate the input and advice.
Ok, but some one should decide the answers to your questions on reinforcing, etc. The usual situation for a barn or garage is to assume the ground will freeze some and there will be some heaving. Then you build taking care of that with joints that can move. To prevent a floor from heaving means you need to go to excessive lengths, usually not practical. Usually that means about 4 feet of non-frost susceptible soil, such as clean gravel, no silt content.
Getting real fancy on reinforcing means a design considering the loads, subgrade soil, etc. requiring hiring a consulting engineer (like me) at maybe $100 an hour. So instead, go with what commonly is done, with a thickness of 4 to 5 inches and with nominal reinforcing such as #4 bars (1/2") at 18 inches each way placed in the middle height of the slab. As my old prof said however, any steel is better than none, consider other steel.
For concrete type ask for 3,000 psi mix (a 5 bag mix) with air entrainment (needed to prevent spalling if you use salt for ice control). Space joints no more than 15 feet, to control where the cracks will form (and they will form). Don't let the driver add calcium chloride to speed up the setting.
Remember to keep the concrete mix stiff as possible, in spite of the truck driver wanting to dump at one end and let it flow to the other end. Back the truck in as far as possible and minimize that "flow". If you do soup it up maybe buy a 6 bag mix to make up for that weakening.
Hog fencing lapped some also could be considered. The rolled out stuff is almost useless, especially if laid on the ground only, but again better than none. If used, use hooks to pull the stuff up into the wet concrete.
Good curing (keeping it moist) will offset some lack of reinforcing.
At doors that need a more stable floor, use a footing down at frost depth and a wall on that. That depth is what ever loocal codes require, but with the clay you, as are likely to have, frost depth is not as deep if it is sandy ground. Check with grave diggers this year for a clue.
Getting real fancy on reinforcing means a design considering the loads, subgrade soil, etc. requiring hiring a consulting engineer (like me) at maybe $100 an hour. So instead, go with what commonly is done, with a thickness of 4 to 5 inches and with nominal reinforcing such as #4 bars (1/2") at 18 inches each way placed in the middle height of the slab. As my old prof said however, any steel is better than none, consider other steel.
For concrete type ask for 3,000 psi mix (a 5 bag mix) with air entrainment (needed to prevent spalling if you use salt for ice control). Space joints no more than 15 feet, to control where the cracks will form (and they will form). Don't let the driver add calcium chloride to speed up the setting.
Remember to keep the concrete mix stiff as possible, in spite of the truck driver wanting to dump at one end and let it flow to the other end. Back the truck in as far as possible and minimize that "flow". If you do soup it up maybe buy a 6 bag mix to make up for that weakening.
Hog fencing lapped some also could be considered. The rolled out stuff is almost useless, especially if laid on the ground only, but again better than none. If used, use hooks to pull the stuff up into the wet concrete.
Good curing (keeping it moist) will offset some lack of reinforcing.
At doors that need a more stable floor, use a footing down at frost depth and a wall on that. That depth is what ever loocal codes require, but with the clay you, as are likely to have, frost depth is not as deep if it is sandy ground. Check with grave diggers this year for a clue.
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cerlawson:
In your opinion, how effective is the reinforcing fibers that you can have added to concrete instead of or in addition to rebar?
The only thing I would add is to make sure that whatever material that is under the slab is well compacted.
In your opinion, how effective is the reinforcing fibers that you can have added to concrete instead of or in addition to rebar?
The only thing I would add is to make sure that whatever material that is under the slab is well compacted.
Fibers in the concrete does wonders. My son's driveway slab on crappy ground works great with fibers. That ios an alternative.
By the way, for the final surface there are some things to think about. Remembering high water content means weaker concrete, don't over work that surface or surface spalling is more likely later on. That means screed as little as possible to get the surface where you want it. Then, minimize any troweling. For a work area use a wood float to get what you want for surface with minimal working. Any troweling for a smoother surface should wait until the trowel rings as you swing it around. Even then, don't work up water to the surface. Power trowels use the same rule. Wait as long as possible. Remember that glassy final surface is like grease when wet. Looks nice but dangerous.
If you cut the joints instead of using wood or other dividers, should be cut as soon as you can get the saw on the surface. As concrete sets, it already starts to shrink. As you might guess, the less water in the mix, the less it shrinks later also.
A funny property of concrete: The less water you use in the mix the stronger it gets, yet if it dries out early on, that is weaker than if you kept it wet for a long period. Tests have been run showing wet cured concrete will continue to strengthen even years later under moist conditions, but more slowly with time. 7 days is the least for moist curing on most jobs.
By the way, for the final surface there are some things to think about. Remembering high water content means weaker concrete, don't over work that surface or surface spalling is more likely later on. That means screed as little as possible to get the surface where you want it. Then, minimize any troweling. For a work area use a wood float to get what you want for surface with minimal working. Any troweling for a smoother surface should wait until the trowel rings as you swing it around. Even then, don't work up water to the surface. Power trowels use the same rule. Wait as long as possible. Remember that glassy final surface is like grease when wet. Looks nice but dangerous.
If you cut the joints instead of using wood or other dividers, should be cut as soon as you can get the saw on the surface. As concrete sets, it already starts to shrink. As you might guess, the less water in the mix, the less it shrinks later also.
A funny property of concrete: The less water you use in the mix the stronger it gets, yet if it dries out early on, that is weaker than if you kept it wet for a long period. Tests have been run showing wet cured concrete will continue to strengthen even years later under moist conditions, but more slowly with time. 7 days is the least for moist curing on most jobs.
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As to fiber in concrete there are several types.
However, finishing can be affected, etc. But do some reading on a search for:
fiber reinforcement in concrete slabs
However, finishing can be affected, etc. But do some reading on a search for:
fiber reinforcement in concrete slabs
wolfman,,, my # is &^% go dawgs!!! My lab was out chaseing wild turkeys in the snow this am. She's 12 years old so they weren't in much danger of getting caught.