Need to pour a small slab

[cowsrus]

I bought a used grain bin last week and I need to pour about a 6x6 slab to stand it on. I,m figuring about 1/2 yd of concrete. Would using redi-mix in a mixer work, or should I mix it myself with sand, gravel & cement. I,m leaning on the redi mix idea, but i'm not sure if it would get as hard as regular cement. any suggestions would be appreaciated.

 

[skyline]

Redimix should work fine. If you have a choice, use a bagged mix with larger rock (not pea gravel). Concrete mixed from sand, gravel, and rock would be more or less strong depending on the proportions that you use. Ordering it from a batch plant (if there is one nearby) would be a lot less work, but I doubt they would deliver in that small quantity.

 

[Mahoney Pursley Ranch]

If your local concrete plant has a u haul type carrier you can rent and get the concrete from them that's the way I would go.

 

[cowsrus]

The nearest batch plant is 30 mi from here, but if I could find something around here that would hold a 1/2 yd or so, I wouldn't mind going after it. I am sure that would be the strongest mix and maybe easier in the long run. I would have to drive that far to get the redi mix anyway.

 

[novatech]

The nearest batch plant is 30 mi from here, but if I could find something around here that would hold a 1/2 yd or so, I wouldn't mind going after it. I am sure that would be the strongest mix and maybe easier in the long run. I would have to drive that far to get the redi mix anyway.

Concrete has tremendous strength under compression and relatively no strength under tension. Given this a stronger mix of concrete will only give you harder concrete. This is OK if the soil you are putting it on is very stable. If the soil moves or is not of load bearing strength the only thing that will hold it together is steel reinforcement, re-bar.
1/2 yard of concrete would be about 40 bags of ready mix.

 

[Hippie Rancher]

the husband is a masonry contractor he said if you don't get it from the plant then mix it yourself

 

[Hippie Rancher]

oh and now he is mumbling to himself about thickness, weight of your bin, height, what kind of steel in the pad, bolting things down etc etc :roll: :lol2:

 

[Scotty]

Just use soem #4 bar on 18" centers and you will be OK. When i use sack crete and the like i alway add 1lb more raw portland to it and some larger aggregate.

 

[Angus In Texas]

It is going to be a little more than 1/2 a yard of concrete if it is 6'x6'x6". You will also have beams I'm assuming? If the bin has legs I would put a pier about 2 feet deep under each leg which will also increase the amount of concrete needed.

As for how to mix it I would go with sacrete and do like scotty says and add some larger rock and a little more cement to the mix. If you know of a mason or someone that has a small mixer, that would be the easiest way. You might try a rental center as well. Sure wouldnt want to mix that much crete by hand.

 

[cowsrus]

It is going to be a little more than 1/2 a yard of concrete if it is 6'x6'x6". You will also have beams I'm assuming? If the bin has legs I would put a pier about 2 feet deep under each leg which will also increase the amount of concrete needed.

As for how to mix it I would go with sacrete and do like scotty says and add some larger rock and a little more cement to the mix. If you know of a mason or someone that has a small mixer, that would be the easiest way. You might try a rental center as well. Sure wouldnt want to mix that much crete by hand.

It is a 8 ton bin with legs. I'm not worried about it sinking in the ground, my concern is to keep it from blowing over.
I have mixer and I think thats a good idea about the piers for the legs. I was going to make it 4" thick x 6' x6' wide. I calculated a little over 1/2 yd. of cement.

 

[Angus In Texas]

Yea if you are doing the piers then 4" slab is plenty thick since there will be very little weight on it. 1/2 yard is probably right then. 6" slab adds 50% when compared to a 4"

 

[alabama]

A 6X6 by 4" will never keep that thing from blowing over. Concrete weight is about 145 pounds per foot cubed. Half a yard is about 1400 pounds. That ain't much compaired to the weight of the bin.
I think you can order 2 or 3 yards for about $150 a yard for 2500 psi concrete and it sure a lot easer to pour. If you have never mixed a yard of concrete you will be suprised just how much work it is.
I would recomend expanding that thing to about a foot out side the post and thicken the edges to a foot and a half and then 6 inch in the middle. Use number 4 rebar with 3 in the bottom of the thickned edges and three on the top of the thickned edges and then a 6 inch spaced mat in the center. Bend rebar in a 90 deg bend to splice the #4 bars on the corners of the thickned edge, they will need to lap 14 inches.
It still would not hurt to set your post deeper to prevent overturning moment however expanding the sides of the pad for a biger area will also rsest overturning but it will need to have the beam such as I I described above around the edge.
Concrete will turn out to be the cheapest part of the project if you want to to last for ever.

If you mix a yard of concrete with 3 shevels of graval to 2 shevels of sand and one shevel of portland cement ,even in a mixer, you will be my hero.

Good luck

 

[Angus In Texas]

wow alabama..... crete is running anywhere from $75 to $85 per yard for 2500 psi. I can't imagine paying $150 a yard

 

[alabama]

wow alabama..... crete is running anywhere from $75 to $85 per yard for 2500 psi. I can't imagine paying $150 a yard

My norm is to buy 4000 psi in the work I do and I also use many add mixtures for setting time and other things. After I typed my first responce I was thinking that 2500 psi should run about 1/2 what i listed. So see consrete is cheep. Never skimp on a foundation. It is the hardest to repair and often cheep to build. Go ahead and buy you 3 yards and make a nice big pad.

 

[backhoeboogie]

If you mix a yard of concrete with 3 shevels of graval to 2 shevels of sand and one shevel of portland cement ,even in a mixer, you will be my hero.

Good luck

It is easier to cheat. Buy remix from the gravel yards that already has the 3 to 2 ratio. 3 tons will cost you about $10.

Get yourself about 30 5 gallon buckets and fill them with remix. Set them on a 4 pallet stack right next to your mixer. Easiest way to get them there is to put them in the front bucket of a tractor and set them out on the pallets. When you get to be an old man this is important. So are 4 pallet stacks to hold the buckets up to the right level (less lifting).

Get yourself 15 buckets with 2 gallons of portland.

Get yourself a coffee can of water. Actually you need about 1 inch less than a can full. Leave the hose trickling to refill the can.

Two 5 gallon buckets of remix, one can of water, two gallons of portland and you have the Hoover Dam recipe. Once you put those components in the mixer, throw the buckets as far behind you as you can to get them the heck out of the way. Dump the mixer in the forms and reload it. Have someone working the concrete in.

 

[backhoeboogie]

By the way, there are about 200 gallons in a yard. The actual number is almost 202 gallons if I remember correctly. That is 40 heaping 5 gallon buckets of concrete FYI.

 

[cowsrus]

BHB, by remix, are you referring to what we call screenings (crusher fine rock & dust)? That stuff sets up almost like cement itself.

 

[Angus In Texas]

No. Remix is referring to river rock plants. We will "Remix" 1 1/4" rock, pea gravel and sand after it has been processed into seperate aggregates. Sometimes the mix is just rock and sand or just pea gravel and sand depending on the application. However if you are in an area that uses limestone for concrete production you might not be able to get remix. If you do find it the definition might be different.

Crusher screenings are from Limestone plants and are best suited to use as pad fill material or gravel road material. They are the fine material that is produced when the limestone is crushed to size for concrete use or other grade specific uses.

 

[cowsrus]

I don't think we can get the remix around here. Could I use the crusher screenings in combination with portland or with sand and portland. The stuff sets up almost like cement by itself. Might be worth experimenting with.

 

[backhoeboogie]

Angus in Texas described it. My choices are pea gravel remix, that has been screened for size. Or else the standard remix that has the prescribed size rock for concrete (I think it is 3/4 to 1 1/2 inch thick without looking it up but I could be wrong). I can buy the standard remix at the concrete plant but it is about 3 times the cost as what it is at the gravel yard. The pea gravel remix is not available at the concrete plant.

Accent Rock in Granbury used to have remix available but they quit carrying it. Sometimes I just buy a little at higher prices if I don't need much and don't want to drive out to the gravel quarry.

If you don't have a gravel quarry close by, call the concrete plant. Generally they will sell it to you. It is more expensive there because they have paid to have it hauled there.