pouring concrete in sections

I need to replace my driveway and I want to do it in 3 sections. It will be a yard of concrete in each section. I don't think my brother and I could pour 3 yards and finish it ourselves. I will be using a mixing trailer to get the concrete to my house to make it a little easier. My question is, how do I connect the sections so they do not settle or move? I live in Colorado and we do have a lot of moisture and freezing temps. Any help would be appreciated thanks in advance.

 

I don't know where you are, but if you have freezing conditions, make sure you have the right concrete or you could be going through a lot of work for nothing (or even worse, more work to correct problems). You should have 4000 psi minimum compressive strength and air entrained concrete.

To tie the slabs together to prevent uneven settlement use 16" to 24" long steel rods (3/8 to 1/4" diameter). Grease one end the prevent the concrete from bonding to it. Place the rods about 16" on center with greased end in in one section of concrete to be placed and the other section extending into the next concrete section. This will allow the concrete to shrink without cracking as it cures, but prevent sections settling differently.

If you can't find smooth rods, you can use normal reinforcing steel and wrap one end with heavy paper after greasing the rod.

Its good that you recognized the need to match the size of the crew to the size of the slab.

Dick

 

Thank you for your reply Concretemasonry.

 

When you excavate you may want to dig a 'foundation' at the perimeter of each section you pour. Say the slab is overall 4" in thickness you may want to
overdig 8 to 12" at the perimeter. The 'foundation' and slab get poured at the same time and the deeper foundation will help secure each section. The reinforceing rod will help tie the slabs to each other. Notch or drill form boards for rods. A little 'underspill' at this lead edge wont hurt for bonding either
good luck
ryk

 

You cannot rely on the contact bond to prevent differential settlement. The individual conrete slabs will shrink slightly breaking the bond. Also, temperature changes (especially in cold climates) will contribute to the shrinkage and slab separation.

Positive connection in the form of steel rods will insure elimination of vertical displacement. As ryk said, you will have to drill the forms for the rods to project through.

Dick